Category: Batteries

Crown Battery Review: CR-430 Pros & Cons, Pricing and Specs

Crown Battery Review: CR-430 Pros & Cons, Pricing and Specs

Review: Crown CR-430 Flooded Lead-Acid Battery

The Crown CR-430 is our go-to battery pick for cost-effective solar energy storage. If you’re willing to perform routine maintenance on your battery bank, these flooded lead-acid batteries provide a low-cost entry point to solar storage.

Crown is our best-selling battery brand, accounting for more than 45% of all battery sales here at Wholesale Solar. In this Crown battery review, we’re going to look at what makes their flooded lead-acid line such an appealing option—especially for off-grid homes where the battery bank will see heavy daily usage.

Specifically, we’ll take a look at specs, pricing, and pros & cons of the Crown CR-430. This 6V / 430 amp-hour battery is the ideal voltage to pair with a wide range of ‘typical’ solar installations, like an off-grid family residence.

If you need a different size battery, take a look at Crown’s line of batteries in our shop. Most of the info in this article broadly applies to the entire line of Crown flooded lead-acid batteries. Your best choice will be the battery that is properly sized for your system.

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Crown CR-430: Price & Specs

  • Model: CR-430
  • Price: $325 (as of 6/10/19)
  • Dimensions: 12.38 × 7.19 × 15.29 inches
  • Weight: 122 lbs.
  • Nominal voltage: 6V
  • Cycling capacity @ 20 hour rate: 430 amp-hours
  • Projected cycle life at 50% depth of discharge: ~1200 cycles

Pros of the Crown CR-430 Battery

Lowest Up-Front Cost

For a lot of people, budget is the most important factor in the decision-making process. The main appeal of the CR-430 is its low price point. It’s the most cost-effective way to get into battery-based solar.

For $325 (at the time of publication), the CR-430 offers an estimated cycle life of 1200 cycles at 50% depth of discharge. A comparable sealed battery would be the Fullriver DC400-6, with a price tag of $583 and an estimated cycle life of 1250 cycles.

The upgrade to sealed batteries removes the need for regular maintenance (which we’ll cover later in this article), so they’re much more convenient to own. But in terms of cost-per-cycle, you’ll get way more mileage out of the Crown CR-430. See the chart below for a side-by-side comparison.

Tried and True Technology

Flooded lead-acid batteries have been around since 1859. It’s the oldest type of rechargeable battery on the market.

With 160 years of history, refinement and advancement of the technology, flooded batteries are very much a known quantity. The chemistry is stable and safe, and there’s no mystery to how long they should last or how to take care of them.

Other types of batteries have less history behind them. Lithium-ion rechargeable batteries were introduced in the 1970s and the industry is still testing specific chemistries and refining their product offerings.

There’s not as much of a track record with these technologies and we don’t necessarily know whether they will live up to their promises. The very well could, but we don’t have as much data about stability and failure rates on these batteries.

Flooded lead-acid batteries are a mainstay of the deep cycle battery market. If you go with the Crown CR-430, you won’t run into any surprises or kinks with untested technology.

Company Reputation

Crown Battery is one of the most established players in the flooded battery industry. They’ve been making batteries since 1926 and continue to be a prominent name in the market.

We’ve been working with them for quite a while and they have a good track record for consistency and responsiveness. They’re quick to respond to support calls, and they work with us on trainings and webinars to make sure the product is well-supported.

It’s reassuring to know they’re accessible in case any issues arise and proactive with their education efforts to reduce failure rates.

Lastly, Crown was founded in Fremont, Ohio, where their corporate and manufacturing facilities are located. It’s always nice to support American manufacturing and job creation efforts when the opportunity is there, and Crown is a company worthy of that support.

Cons of the Crown CR-430 Battery

Required Maintenance

The tradeoffs for flooded lead-acid batteries are pretty simple: they cost less, but you have to commit to routine maintenance to keep them working.

Every month or so, the batteries need to be refilled with distilled water which evaporates during the charging process. They also require periodic equalization charges, which is essentially a controlled overcharge to help the batteries stay healthy.

It only takes a couple of minutes, but you still have to commit to the maintenance on a regular schedule or else the batteries will be damaged prematurely. It’s a simple task, but there are drastic consequences if you skip it.

If you’d rather not be burdened by this responsibility, we’d recommend a sealed lead-acid or lithium battery, neither of which require you to commit to upkeep. In our review of the Fullriver DC400-6, we called this a “convenience upgrade.” You pay a bit more so you don’t have to worry about checking in on your battery bank.

Can’t Install Inside

Another reality of flooded lead-acid batteries is that they emit gases during operation. As a result, there are some restrictions on where you can install them. They need to be built according to local codes, in a well-ventilated enclosure, away from flammable materials and other hazards.

Due to the off-gassing, you likely want to build your battery bank in a shed or garage, or put it outdoors in a ventilated battery enclosure. In contrast, sealed lead-acid and lithium batteries do not off-gas, which means they can be safely installed inside your home.

This can also make flooded batteries more costly to install. Though the batteries themselves are cheaper, there can be extra costs associated with building a new enclosure for the battery bank, which should be taken into account when evaluating the true cost of ownership.

Ideal Application for the Crown CR-430

It’s pretty easy to understand why the Crown CR-430 has been one of our best-selling batteries for years. It doesn’t cost a lot up front, and the cycle life stacks up against much more expensive batteries so long as you commit to a few minutes of maintenance on a monthly basis.

Since flooded batteries require regular care, the ideal use case is off-grid properties that are occupied full-time. Flooded batteries self-discharge quickly and need to be recharged after every cycle, so it makes the most sense to build them in an application where they will be cycled on a daily basis.

Due to these restrictions, we don’t recommend using flooded batteries for vacation homes, industrial worksites, or other applications where people won’t be around to use the batteries on a daily basis or commit to their upkeep. Sealed batteries are better in those situations because you don’t need regular check-ins to keep them working.

Need more help with battery bank sizing, or just want some advice on finding the right battery for your project? Connect with us for a free consultation or grab a copy of our free solar battery guide linked below.

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Fullriver Battery Review: DC400-6 Sealed AGM Battery

Fullriver Battery Review: DC400-6 Sealed AGM Battery

Fullriver Battery Review: DC400-6

  • 6V / 415ah capacity @ 20 hr. charge rate
  • Projected lifespan of 1250 cycles @ 50% depth of discharge
  • Convenient option for daily off-grid use
  • Ideal for occasional use in remote locations (like a vacation cabin or industrial site) due to maintenance-free nature

Fullriver makes our favorite Sealed AGM (Absorbent Glass Mat) battery on the market: the DC400-6, a 6V battery with 415 ah of capacity.

This battery is ideal in situations where the battery bank may go an extended period of time between charge cycles, like at a vacation cabin or a remote telecom site. It’s also a great option for daily off-grid use if you prefer to avoid the maintenance required of flooded batteries.

This Fullriver battery review will cover over the pros and cons of their DC400-6 Sealed AGM (Absorbent Glass Mat) battery in depth and explain some ideal use cases for AGM batteries.

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Price & Specs

  • Model: DC400-6
  • Price: $582.49 (as of 5/16/19)
  • Dimensions (LxWxH): 11.61 × 7.05 × 16.69 inches
  • Weight: 123.2 lbs
  • Nominal voltage: 6V
  • Cycling capacity @ 20 hour rate: 415 ah
  • Projected cycle life at 50% depth of discharge: ~1250 cycles

It’s worth noting that Fullriver carries a wide range of 2V, 6V and 12V AGM batteries. We chose to highlight the DC400-6 because it is our best-selling AGM battery with ideal charging characteristics to pair with a broad range of off-grid systems.

You might be better served with another option depending on the scope of your project. For example, 2V batteries work better for larger systems (more on that below). Check out our tips for sizing off-grid systems and chat with your system designer to find the best option for your project.



The main difference between flooded and sealed lead-acid batteries is that flooded batteries need routine maintenance to keep them in working condition. Every month or so, you need to refill flooded batteries with distilled water, which evaporates during the charge cycling process.

If you are the type of person who loves to get hands-on with DIY projects, you might enjoy the routine maintenance required to keep flooded batteries in good shape.

But most people don’t want their solar system to be the center of their entire life. If you’re the type of person who procrastinates taking your car to the shop for regular tune-ups, you will likely prefer the “set it and forget it” nature of sealed batteries, which don’t require any maintenance check-ups.

If you want a battery that just works without any extra hassle, the maintenance-free Fullriver AGM battery is our top pick.

No Off-Gassing

Flooded batteries emit a gas byproduct as a regular part of their operation. Off-gassing can be dangerous if it builds up in a poorly ventilated area.

For that reason, flooded batteries need to be installed away from living quarters in a well-ventilated enclosure, which can add to overall project costs.

Fullriver’s AGM battery is sealed, and it does not emit gas as part of the cycling process. This means that it can be safely installed indoors without fear of Hydrogen gas buildup.

Install in Any Configuration

Sealed AGM batteries are just that—sealed. You can install them on their side and they won’t leak.

Sealed AGM batteries won't leak, even if installed on their side.

For that reason, Fullriver’s AGM battery is a popular option in RV systems, where vibrations from the road can cause the fluid in the battery to slosh around. Where flooded batteries would spill, the Fullriver AGM stays sealed tight.

They are also more flexible for home installs. If you have a shed or a workshop and need to save floor space, the Fullrivers can be installed sideways without spilling or leaking. That extra bit of versatility is convenient as you plan out your system.

Quality Support & Reputation

Lastly, nobody likes buying from a company that makes it a headache to get support for their products.

We’ve stocked Fullriver for several years and have a great working relationship with them. In cases where our customers have had to contact Fullriver customer support, they’ve been quick and efficient at solving issues.

Generally, we’ve found their support team to be responsive and knowledgeable, which gives us peace of mind that questions and issues will be resolved quickly when they do pop up.


Higher Cost

At the time of publication, we sell Fullriver’s DC400-6 AGM battery for $583 apiece. That’s a fair bit more than a comparable flooded battery, the Crown CR430, which goes for $325 apiece.

Fullriver projects their batteries to last 1250 cycles at 50% Depth of Discharge (DoD), while the Crown CR430 is good for 1200 cycles at 50% DoD. (A cycle refers to the battery being drained and then recharged again—essentially, one day of use.)

Given the similarities in amp-hour capacity and cycle life, the performance of these batteries is fairly comparable. So why does the AGM cost more?

When I speak with clients, I like to be honest and call it what it is: a convenience upgrade. Flooded batteries require monthly maintenance checks, and there is the potential to come into contact with battery acid while refilling the water, which will burn your skin. AGM batteries are maintenance-free, so you never have to check up on them.

AGM batteries cost more to manufacture because the design is more complex, with the electrolyte suspended in a fiberglass mat, which prevents it from spilling. Essentially, you are paying a premium for the lack of maintenance and the right to forget about your solar system so you can get on with the rest of your life.

If you are the type of person who likes to get hands-on with DIY projects, by all means, opt for flooded batteries. They will deliver similar performance at a much lower cost, so long as you stay on top of a regular maintenance schedule.

Not Suitable for Large Systems

Most off-grid systems tend to be on the smaller side because batteries are quite expensive (the single most costly component of any off-grid system). Off-grid homes tend to take measures to cut down on energy usage, like using efficient appliances and forgoing central heat and A/C units, to get the most out of the battery bank.

Still, I occasionally work with people who need to build large off-grid systems. For these systems, we don’t use the Fullriver batteries because it is best practice to limit 6V battery banks to 2 strings of 8 batteries each (16 batteries total, or 38.4 kWh of storage).

We are limited to 8 batteries in a string because it matches the voltage requirements of the inverter (6V x 8 batteries = 48V string, which matches the nominal voltage of a 48V inverter).

And we don’t run more than 2 strings in parallel because it creates too much resistance between the battery strings. This leads to unbalanced charging and discharging across the strings, which will create uneven charge levels in the batteries.

This isn’t a knock against the Fullriver DC400-6 battery, it’s simply a limitation of the system design process. To solve this issue, we turn to 2V batteries so we can fit more batteries in a string (24 batteries on a 48V inverter).

For large off-grid systems, we turn to the Crown 2CRV1200 or Fullriver DC1150-2.

Ideal Application

Sealed AGM batteries are more convenient and less complex than flooded batteries. Unlike flooded batteries, there’s no threat of ruining your AGM batteries early by neglecting a regular maintenance schedule.

You’ll pay a premium to upgrade to the Fullriver DC400-6 battery, but the tradeoff is that you never have to deal with messy battery maintenance. For many people, ditching the burden of monthly check-ins is well worth the extra cost.

If that appeals to you, the Fullriver DC400-6 is our pick for our preferred sealed battery for daily off-grid use.

There’s another use case where this battery shines: systems that only see occasional use. If you have a hunting cabin that you visit once a month, sealed batteries are practically mandatory.

Flooded batteries will start to self-discharge and if they are not regularly cycled. They would quickly die if you tried to use them in a system where you would not have access to perform regular maintenance.

Sealed batteries have much slower self-discharge. They can sit dormant without upkeep for longer periods and better maintain a charge when you come to visit. That makes the Fullriver DC400-6 our recommended battery for remote systems such as a hunting cabin.

For more info, check out our solar battery guide linked below. If you’d like some help designing a system, feel free to call us at 1-800-472-1142 or request a quote on our website.

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Battery Maintenance Tips: How To Care For Your Deep-Cycle Batteries

Battery Maintenance Tips: How To Care For Your Deep-Cycle Batteries

How Do I Maintain Deep-Cycle Batteries?

  • Program your voltage set points so that the battery bank charges at the proper voltage.
  • Refill flooded lead-acid batteries with distilled water every 2-4 weeks as needed.
  • Regularly check battery state of charge. Apply an equalization charge to flooded batteries every 90 days. (Do not equalize sealed lead-acid or lithium batteries.)
  • Clean terminal connections and cables to prevent corrosion.

Solar batteries are the most costly component of any off-grid solar system. It’s important to program them properly and stick to a regular battery maintenance schedule to keep them running efficiently for years. Neglecting the proper setup and maintenance routine can shorten the lifespan of your batteries and void the product warranty.

Some battery types, like Lithium-ion, require little to no maintenance after the initial setup. Other battery types (especially flooded lead-acid) need regular upkeep to stay in good condition.

No matter what type of batteries you own, this article will help you program your battery bank and give some battery maintenance tips to keep your system running smoothly.

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Initial Programming

The first time you bring your system online, you’ll need to program your battery chargers to the proper charging settings for your battery bank. These settings dictate parameters like charging voltage and current.

This is where you program voltage set points, the charging voltages applied to the battery during each stage of the charging cycle. Batteries typically charge in 3 phases—bulk, absorb, and float, which can be summarized as follows:

  • Bulk: High current to replenish charge and bring voltage up as quickly as possible (below 80%)
  • Absorb: Charge rate slows as batteries approach full state of charge (~80-100%)
  • Float: Batteries receive a trickle charge at 100% to stay fully charged

Each stage requires the charger to be set at a specific voltage, which is based on the requirements of your battery.

Programming the voltage set points accurately is critical to ensuring the long-term health of your batteries. Setting the wrong charge parameters will make your batteries charge improperly, shortening their lifespan.

There are other values to set during the initial programming phase as well:

  • Absorb time: The amount of time the charger spends in the absorb phase.
  • AC input amps: Maximum input current from grid or generator, to ensure the combined current from the battery charger and loads doesn’t exceed the rating of the generator. Depends on generator size or grid input breaker. See manual for details.
  • Max charge rate or charge current limit: Maximum charging current, either expressed as a percentage of the charger output or total maximum charging amps. This setting is used to limit charger output, to make sure your batteries are not overcharged with too much current.
  • Temperature compensation: Adjusts the battery charger for operation in various temperature ranges. Most chargers include a battery temperature sensor.

These settings are different for every battery and charger. Check the spec sheets or installation manuals for your batteries and chargers to find the specific values for each of the above settings.

Programming your equipment according to the settings recommended in the manual is the first step toward ensuring the long-term health of your battery bank.

Flooded Lead-Acid Battery Maintenance Tips

Flooded lead-acid batteries require regular maintenance to function properly. We recommend checks every 2-4 weeks to keep the battery bank tuned up.

Note: always follow proper safety procedures when working around batteries. Wear eye protection and gloves, remove any jewelry, and secure loose clothing and long hair.

Add distilled water every 2-4 weeks

Flooded lead-acid batteries lose water during the charge cycle. They must be refilled regularly with distilled water to function properly and stay healthy.

Note that you should only use distilled water. Non-distilled water (like tap water) will introduce small particles and contaminants, which weakens the battery chemistry.

Check water levels every 15-30 days and refill as necessary. Your watering schedule depends on your local climate, charge settings and specific application. It may be useful to keep a log to track how often your batteries need to be refilled.

  1. Check water level when batteries are fully charged.
  2. Open the vent well to check the water level.
  3. Add water to just below the maximum water level line. DO NOT overfill past this line. The battery installation manual should indicate where to find the maximum water level line.

Check battery state of charge (SoC):

Use a refractometer to keep an eye on how charged your batteries are. The refractometer measures the specific gravity of your batteries. This video explains how to use a refractometer:

Consult the charts published by your battery manufacturer to find your battery state of charge based on their specific gravity reading. An example chart is shown below.

If your batteries are not holding charge even after a full charge cycle and equalization, they are likely defective, damaged, or have reached the end of their lifespan and are starting to lose some capacity.

Some inverters use a battery monitor to measure state of charge. These battery monitors typically rely on a shunt for measuring the total current coming in and out of the battery bank.

Battery monitors are a useful tool for daily monitoring, but they require proper setup. If they aren’t installed or programmed correctly they can provide false readings.

Even if you have a battery monitor, we still recommend checking the specific gravity with a refractometer on a regular basis. It helps verify the battery monitor is accurate and ensures your batteries reach a full charge.

Use a refractometer to check the specific gravity of your flooded lead-acid batteries.

Equalization Charges

Batteries should be equalized occasionally to make sure each cell is equally charged. Apply a controlled overcharge once every 30-90 days, or whenever individual batteries are imbalanced (reading a different voltage or specific gravity).

  1. Check water level before initiating an equalize charge.
  2. Turn off any loads.
  3. Set your charger at the Equalize voltage specified in your battery manual.
  4. Start the Equalize charge. Gassing and bubbling is normal during this process.
  5. Stop charging and take specific gravity readings every hour. The EQ process is complete when the specific gravity stops rising.

Other Routine Flooded Lead-Acid Battery Maintenance

  • Tighten the battery cable connections as needed. Wear gloves/eye protection and use insulated tools.
  • Clean terminal connections & cables to prevent corrosion. Mix baking soda and distilled water into a paste and apply with a wire brush. Rinse cleaning residue and dry with a cloth or paper towel.
  • Keep the top of the batteries clean from dust and debris to avoid creating a current pathway or electrical leakage across the top of the battery.

Sealed Lead-Acid Battery Maintenance

Sealed lead-acid batteries do not need to be filled with water or equalized. They require very little maintenance other than the occasional check-up on the battery’s state of charge.

Check Battery State of Charge (SoC):

Use a multimeter to keep an eye on how charged your sealed lead-acid batteries are based on the voltage. A multimeter is equipped with positive and negative probes which allows the meter to get a DC voltage reading from the battery.

Your battery manual should contain a chart that estimates the battery’s state of charge based on these voltage readings (like the one in the previous section).

To get the most accurate reading, your batteries should be tested in a resting state. Let your batteries rest for at least 2 hours (no charging/discharging) before taking the voltage reading. Attempting to use the multimeter when batteries are being charged or discharged is going to result in a higher or lower voltage, depending on the load.

If your batteries fail to approach 100% SoC even after a full charge cycle, they are likely defective, damaged, or have reached the end of their lifespan.

Equalization Charges

DO NOT equalize sealed batteries! This applies to flooded lead-acid batteries only.

Other Maintenance

  • Tighten the battery cable connections as needed. Wear gloves/eye protection and use insulated tools.
  • Keep the top of the batteries clean to prevent them from getting dusty and grimy.

Lithium-Ion Battery Maintenance

Fortunately, lithium batteries require little to no maintenance (one of the main appeals when comparing lithium vs. lead-acid batteries). Once they are set up properly, they don’t need any checks aside from the occasional state-of-charge reading to ensure they are holding a charge.

Lithium battery manufacturers sell a tool to gauge the battery’s state of charge (SoC). The tool typically communicates with the built-in Battery Management System (BMS) to get an accurate SoC reading. Simply hook the monitoring tool up to the battery and read the SoC value from the display screen.

Discover Battery makes their own monitoring tool called a Battery Discharge Indicator, while Simpliphi recommends Victron battery monitors for their batteries.

Other Maintenance

  • Tighten the battery cable connections as needed. Wear gloves/eye protection and use insulated tools.
  • Keep the top of the batteries clean to prevent them from getting dusty and grimy.

A Note About System Design

That’s it for our maintenance tips, but it’s worth pointing out that maintenance is only effective if your system is well-designed and your battery bank has been properly sized.

In our experience, many cases of battery bank failure can be attributed to poor system design. People buy the wrong size battery bank or solar array, not taking into account key factors like temperature, local sun hours, and discharge depth. If you simply don’t have enough panels to fully charge your batteries, they’re destined to fail at some point.

The solar array, battery bank and inverter all need to be the proper sizes for the batteries to stay healthy. You also need enough amperage left over to charge the battery bank after accounting for loads that need to be powered (15 charging amps per 100ah is recommended for lead acid batteries). Take a look at our off-grid system sizing guide for more info.

Stuck on system design? Get in touch for a free consultation with one of our solar designers. We provide design advice that is tailored to your application, and our in-house tech team closely reviews proposed plans to avoid the common pitfalls outlined above.

More Battery Maintenance Resources

If you follow this guide, you’re well on your way to ensuring a long lifespan and peak performance from your battery bank. For more battery advice, grab our free Solar Battery Guide linked below.

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Lead-Acid Battery Comparison: Pros and Cons of Flooded, Sealed, AGM and Gel Batteries

Lead-Acid Battery Comparison: Pros and Cons of Flooded, Sealed, AGM and Gel Batteries

Lead-Acid Battery Breakdown: Flooded vs. Sealed

  • Flooded lead-acid batteries are most cost-effective option, but require regular upkeep
  • Sealed batteries (AGM and Gel) cost more but do not require regular maintenance
  • AGM batteries resist vibration and can handle higher charge/discharge rates
  • Gel batteries can withstand high temps and work best with slow, deep discharge

Batteries come in many shapes and sizes. In the solar industry, two battery chemistries work well for our purposes: lead-acid and lithium.

We’ve written an in-depth comparison of lead-acid vs. lithium batteries previously on this blog, but here are the Cliff’s Notes: lithium is the premium option, with a longer lifespan and fewer maintenance requirements. Lead-acid costs much less up front, but regular check-ins are required to keep the battery bank working properly.

This article will focus on the differences between the main lead-acid battery types used in the solar industry. You’ve got flooded lead-acid and sealed lead-acid batteries, and the latter group can be broken down into AGM (absorbent glass mat) and gel batteries.

Every battery type has a different purpose and use case, so let’s go over the pros and cons of each.

Flooded Lead-Acid Batteries

For many years, the flooded lead-acid battery has been the standard in the solar industry. This type of battery is also used in golf carts and forklifts. They are the most cost effective and longest lasting of the lead-acid batteries.

Flooded lead-acid batteries contain an electrolyte that is free to move around in the battery encasement. When charged, the battery acid and lead plates react to store electricity.

These batteries are meant to be mounted upright so that the electrolyte does not leak out of the caps on top. (Since sealed batteries are…well, sealed, you can mount them in any orientation without fear of them leaking. Not the same for flooded batteries.)

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While this is the most economic battery on the market, it will only reach its potential lifespan if they are maintained properly. The levels must be checked monthly and topped off with distilled water to ensure the longest possible lifespan.

Note: flooded lead-acid batteries release toxic hydrogen gas when charging. They need to be enclosed and vented to the outside to prevent this gas from being trapped and creating a hazardous environment.

Related Product: Crown CR430 6V Flooded Lead-Acid Battery

Sealed Lead-Acid Batteries

The sealed lead-acid batteries are very similar to the flooded version, but there is no access to the inside compartment. This means that you do not have to add distilled water. The electrolyte is sealed inside, and there is enough to allow the battery to live out a calculated number of cycles.

You sometimes see these referred to as VRLA (valve regulated lead-acid) batteries, because they have a small valve to allow for the escape of the gasses that occur during charging.

AGM (Absorbent Glass Mat) Batteries

Absorbent Glass Mat batteries are the most popular VRLA battery because they can work in a wide range of conditions. The electrolyte is suspended in a thin fiberglass mat that is situated between the lead plates. This allows the battery to be resistant to vibration, which makes them a great choice for RV and other mobile applications.

They can also be mounted in any orientation. It is common to see them mounted on their sides for convenient placement and wiring.

AGM batteries are more expensive than flooded lead-acid batteries, and they do not last quite as long. But for that extra price, you get the luxury of not having to maintain the batteries or deal with as much gas that is released during the charging phase.

They are perfect for mobile applications, places where leaked acid would be problematic, remote locations where maintenance will not be possible on a regular basis, and places where the batteries could be subject to extremely cold temperatures.

Related product: Fullriver 6V 415Ah AGM battery

Gel Batteries

Gel batteries are another VRLA battery very much like an AGM, but they use a thick paste that allows the magic to happen rather than the fiberglass mat.

The main difference between gel and AGM batteries is the charge rates. AGM batteries can handle higher charge and discharge rates than gel batteries.

Gel batteries are the most costly of the VRLA batteries, but excellent candidates for projects that need a very slow deep discharge. They also last a bit longer in hotter temperatures, so you might pick them if you are concerned about high ambient temperatures in the space where the batteries are enclosed.

Gel batteries are more expensive than other lead-acid battery types, so they are not ideal outside a handful of specific solar applications (very hot climates, mainly). The technology has been eclipsed by other battery types that have been developed more recently.

It is very common for people to mistake a Gel for an AGM, and this can affect the lifespan of the battery. Gel batteries are the most sensitive of the VRLA batteries, and It is critical that the correct charging parameters are used when you have a Gel battery in your application.

My Experience Living Off the Grid

When I first started living off the grid in 1996, I had never heard of a Gel or AGM battery. Everyone I knew that was exploring the off-grid lifestyle used the flooded golf cart batteries. Once I started working in the industry and doing more installations, I started seeing more battery options.

I quickly realized that the bigger flooded batteries called L-16s were the standard in most of our nicer installations. These are sometimes referred to as a forklift battery. While the cost per amp hour was similar to a golf cart battery, it became evident that the L-16s lasted longer. It was explained to me that the bigger the battery, the thicker the lead plates would be, therefore gaining a better lifespan.

About three years ago, my flooded batteries were at the end of their life, and I opted to get AGM batteries this time around. While I don’t really notice much performance difference, I am relieved to not have to crawl under my stairs to check water and maintain the batteries anymore. Even though my L-16s were in a sealed vented compartment, once in a while I would catch a whiff of something that must have been the hydrogen gas seeping out. I haven’t smelled that since, and it was worth every penny to make the switch.

For more advice on which battery type is best suited for your project, chat with one of our system designers or check out our Solar Battery Guide linked below.

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Lead-Acid vs Lithium Batteries: Which Are Best For Solar?

Lead-Acid vs Lithium Batteries: Which Are Best For Solar?

Lead-acid vs. Lithium Battery Comparison

Lead-acid batteries cost less up front, but they have a shorter lifespan and require regular maintenance to keep them running properly. Lithium batteries are much more expensive up front, but they are maintenance-free and have a longer lifespan to match their higher price tag. This article offers a side-by-side comparison of both options.

Welcome to our Solar 101 series! This article goes over a choice you’ll need to make if you buy a battery-based solar system, either to move off the grid or to add energy storage to your grid-connected home.

Specifically, we’re going to look at lead-acid vs. lithium-ion batteries — the two main battery types used for solar. Here’s the summary:

Lead-acid is a tried-and-true technology that costs less, but requires regular maintenance and doesn’t last as long.

Lithium is a premium battery technology with a longer lifespan and higher efficiency, but you’ll pay more money for the boost in performance.

Let’s go over the pros and cons of each option in more detail, and explain why you might choose one over the other for your system.

Lead-acid vs. Lithium Solar Batteries: The Basics

When you build a solar system, you have three main battery options:

Flooded Lead-Acid (FLA)

The distinguishing feature of FLA batteries is that the plates are submerged in water. These must be checked regularly and refilled every 1-3 months to keep them working properly.

Falling behind on upkeep can shorten the life of the batteries and void the warranty. FLA batteries also need to be installed in a ventilated enclosure to allow battery gases to escape.

Sealed Lead-Acid (SLA)

SLA batteries come in two types, AGM (Absorbent Glass Mat) and Gel, which have many similar properties. They require little to no maintenance and are spill-proof.

The key difference in AGM vs. gel batteries is that gel batteries tend to have lower charge rates and output. Gel batteries generally can’t handle as much charge current, which means they take longer to recharge and output less power.

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The best lithium battery chemistry for solar applications is Lithium Iron Phosphate, shortened to LiFePO4 or LFP batteries. This new technology lasts longer and can be put through deeper cycles. They also require no maintenance or venting, unlike lead-acid batteries.

Lithium batteries cost more up front, but the extra efficiency means you can potentially spend less per kilowatt-hour of capacity over the lifespan of the battery.

Lead-acid vs. Lithium Batteries: Pricing Breakdown

Let’s look at how much it would cost to build a battery bank with all three options.

We’re not just interested in the up-front cost, but also the cost of ownership over the life of the system. As an example, we’ll look at how much the batteries would cost to power this 5.13 kW off-grid system, which we sell for $12,899 at the time of publication.

In an off-grid environment, you want to look at the estimated cycle life since you are cycling your batteries on a daily basis. This system would produce an estimated 23.08 kWh per day in the summer and 11.54 kWh per day in the winter.

Here’s how much it would cost to buy batteries for that system over the first 10 years. We are comparing the following battery banks:

Lead-Acid vs. Lithium Batteries: Cost Breakdown

A Few Notes About This Chart

We are estimating that the lead-acid batteries will be replaced 3 times over a 10 year period, the lifespan of 1 lithium battery. This comparison is based on the length of the warranty offered by the manufacturers.

We’ve done our best to give an apples-to-apples comparison of these batteries based on their printed specs. However, in real-world applications, factors like discharge depth, temperature, charging source, overall system design, and your willingness to perform regular maintenance will affect the true performance of your batteries.

5 Key Differences Between Lead-acid and Lithium Batteries

1. Cycle life

When you discharge a battery (use it to power your appliances), then charge it back up with your panels, that is referred to as one charge cycle. We measure the lifespan of batteries not in terms of years, but rather how many cycles they can handle before they expire.

Think of it like putting mileage on a car. When you evaluate the condition of a used car, mileage matters a lot more than the year it was produced.

Same goes for batteries and the number of times they’ve been cycled. A sealed lead-acid battery at a vacation home may go through 100 cycles in 4 years, whereas the same battery might go through 300+ cycles in one year at a full-time residence. The one that has gone through 100 cycles is in much better shape.

Cycle life is also a function of depth of discharge (how much capacity you use before recharging a battery). Deeper discharges put more stress on the battery, which shortens its cycle life.

2. Depth of Discharge

Discharge depth refers to how much overall capacity is used before recharging the battery. For example, if you use a quarter of your battery’s capacity, the depth of discharge would be 25%.

Batteries don’t discharge fully when you use them. Instead, they have a recommended depth of discharge: how much can be used before they should be refilled.

Lead-acid batteries should only be run to 50% depth of discharge. Beyond that point, you risk negatively affecting their lifespan.

In contrast, lithium batteries can handle deep discharges of 80% or more. This essentially means they feature a higher usable capacity.

3. Efficiency

Lithium batteries are more efficient. This means that more of your solar power is stored and used.

As an example, lead acid batteries are only 80-85% efficient depending on the model and condition. That means if you have 1,000 watts of solar coming into the batteries, there are only 800-850 watts available after the charging and discharging process.

Lithium batteries are more than 95% efficient. In the same example, you’d have over 950 watts of power available.

Higher efficiency means your batteries charge faster. Depending on the configuration of your system, it could also mean you buying fewer solar panels, less battery capacity and a smaller backup generator.

4. Charge Rate

With higher efficiency also comes a faster rate of charge for lithium batteries. They can handle a higher amperage from the charger, which means they can be refilled much faster than lead-acid.

We express charge rate as a fraction, such as C/5, where C = the capacity of the battery in amp hours (Ah). So a 430 Ah battery charging at a rate of C/5 would receive 86 charging amps (430/5).

Lead-acid batteries are limited in how much charge current they can handle, mainly because they will overheat if you charge them too quickly. In addition, the charge rate gets significantly slower as you approach full capacity.

Lead acid batteries can charge around C/5 during the bulk phase (up to 85% capacity). After that, the battery charger automatically slows down to top off the batteries. This means lead acid batteries take longer to charge, in some cases more than 2x as long as a Lithium alternative.

5. Energy Density

The lead-acid batteries featured in the comparison above both weigh around 125 pounds. The lithium battery checks in at 192 pounds.

Most installers can handle the extra weight, but DIYers might find the lithium batteries more challenging to install. It’s wise to enlist some help lifting and moving them into place.

But that comes with a tradeoff: the energy density of lithium batteries is much higher than lead-acid, meaning they fit more storage capacity into less space.

As you can see in the example, it takes two lithium batteries to power a 5.13 kW system, but you’d need 8 lead-acid batteries to do the same job. When you take the size of the entire battery bank into account, lithium weighs less than half as much.

This can be a real benefit if you need to get creative with how you mount your battery bank. If you are hanging an enclosure on the wall or hiding it in a closet, the improved energy density helps your lithium battery bank fit into tighter spaces.

Lithium vs. Lead-Acid: Which Should You Choose?

Lithium and lead-acid grade out at comparable prices over the life of ownership, but lithium is a much steeper investment up front. We wouldn’t recommend it unless you use your system on a daily basis.

Here are the battery types we’d recommend for a variety of applications:

Full-Time Off-Grid Residence

Flooded Lead-Acid or Lithium.

If you live off the grid full-time, your best bet is FLA (if you don’t mind regular maintenance) or the premium Lithium option for heavy use.

Off-Grid Cabin / Vacation Home

Sealed Lead-Acid.

If you own something like a hunting cabin or a vacation home, you’ll only be there a few times a year. That means you won’t be able to keep up with the maintenance required of FLA batteries.

Spend a bit extra on SLA instead. They’re zero-maintenance, so they won’t die if they sit idle for a few months.

Battery Backup System

Sealed Lead-Acid.

Let’s say you are building a system with battery backup for emergency power outages. Ideally, you will only use those batteries once a year (a few times if you live in an area with an unreliable power grid). They won’t see enough use for you to invest into lithium, and you don’t want to perform maintenance on FLA batteries you use once a year.

Go with SLA, which (again) don’t require upkeep.

Remote Industrial Use

Sealed lead-acid or lithium.

The decision-making process is pretty much the same here. Lithium could be worth it to power an industrial site that sees heavy use. If you are powering basic monitoring equipment at a remote outpost, SLA will get the job done cheaper, and you still won’t have to worry about maintenance visits.

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Discover vs. SimpliPhi: What’s the best lithium battery for solar energy storage?

Discover vs. SimpliPhi: What’s the best lithium battery for solar energy storage?

When we design off-grid solar systems with lithium batteries, we work with two main brands: Discover and SimpliPhi.

These two manufacturers are major players in the lithium battery market, which is the premium option for solar storage.

In this article, we’ll compare Discover AES vs. SimpliPhi Lithium batteries and give our honest opinion on when you might choose one over the other.

The alternative to lithium would be lead-acid batteries, which are less expensive but don’t last as long or run as efficiently. We review lead-acid batteries alongside lithium options in our review of the best solar batteries on the market.


First, let’s talk about what the two options have in common.

They’re both the same chemistry: Lithium Ferro Phosphate (LFP). LFP is a different type of Lithium battery designed to be very stable and safe, with high output to handle a demanding off-grid environment.

Lithium batteries have some inherent advantages over lead-acid batteries:

  • Longer lifespan
  • No maintenance
  • More efficient power usage
  • More usable storage capacity (deeper discharges)
  • No off-gassing / ventilation

Both Discover and SimpliPhi will offer a stable battery with a long lifespan. You won’t need to check in for regular upkeep like you would with lead-acid batteries.

They are also comparable in price. If you compare Discover’s 48V battery to SimpliPhi’s 48V battery, the cost per kilowatt hour of capacity is almost exactly the same.

At the time of publication, our price for 48V Discover AES batteries works out to $1 per Wh of capacity, while we charge 98 cents per Wh for a comparable SimpliPhi battery.

We compare 48V options because they are the highest efficiency and most cost-effective for most off-grid systems. Also, it just so happens that most household inverters come in 48V, so it makes the most sense to match the battery voltage to commonly used inverters.

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It is worth noting that the cost per Wh depends on size and features. Many of our SimpliPhi 24V lithium batteries come in at a lower price point than their Discover counterpart. And of the two, SimpliPhi is the only one who makes a 12V option.

But due to inverter and charge controller specs, the apples-to-apples comparison most people care about is the 48V offering, because most off-grid residences are going to run off of 48V battery banks.

Why choose Discover’s Lithium Batteries?

Discover batteries thrive in large-scale systems. They have two main advantages: battery sizing and ease of installation.

Battery Size

The largest battery SimpliPhi makes has a 3.5 kWh capacity. In contrast, Discover’s largest battery nearly doubles that capacity, at 6.6 kWh. (Remember: even though the sizes are different, the cost-per-kWh is almost identical.)

Recommended product: Discover 6.6 kWh 48V Lithium Battery

If you are building a battery bank for a typical off-grid residence, it will take fewer Discover batteries to reach the same target capacity. For example, if you need 26 kWh of capacity, you could do that with 4 Discover AES 6.6 kWh batteries. It would take 8 SimpliPhi 3.5 kWh batteries to cover the same ground.

Ease of Installation

From an installation and wiring standpoint, Discover batteries are also easier to work with. SimpliPhi batteries have stricter cabling requirements.

You’ll need to run each SimpliPhi battery into a busbar, which is a terminal for all your wire connections. The busbar then combines all of the batteries in parallel. The extra cable management can be a pain because all of the wires need to be equal length.

It’s critical that all cables are the same length, because the individual batteries are not communicating with each other directly.

SimpliPhi battery busbar
SimpliPhi’s lithium batteries wire into a busbar, which manages the cabling. Image Source

Discover AES batteries don’t have the same strict cabling requirements. They can plug into each other to communicate and synchronize output.

This results in less wire overall and easier installation, because you can connect several batteries together in parallel without needing to run individual wires to a busbar. And because Discover batteries have more capacity, you’ll have fewer batteries to wire together.

All this means that Discover batteries take less time and money to install, and the difference is amplified in larger systems. That isn’t to say you can’t build large SimpliPhi battery banks — only that it’s a bit more tedious to do so.

It’s not a big deal if you’re bringing in an experienced installer to hook up your system. But if you plan to do a DIY install (as many of our customers do), consider that it may be a little more complex to install SimpliPhi batteries on a large scale.

Charge Capability

Discover batteries also have higher output, which means they can charge (and discharge) faster.

Charging current is measured in amps and commonly expressed as a percentage of total battery capacity. For example, if a 100 amp hour battery can output 100 amps, that is a rate of 1C. (C stands for Capacity.)

Here’s how continuous charge and discharge current looks for the two 48v models we are comparing:

  • Discover AES 6.6kWh 48v: 1C
  • Simpliphi PHI 3.5kWh 48v: 1/2C

This means the Discover batteries can handle twice as much charge and discharge current. That likely has to do with differences in the battery management system (BMS) and overall battery design.

The BMS works to manage voltage, current and data logging for your battery bank. These manufacturers use different BMS designs, which may explain why Discover’s batteries charge faster and handle higher current.

This means that Discover batteries can be interconnected for faster charging and higher output. They plug into each other, allowing them to communicate and synchronize charge and discharge current.

SimpliPhi’s batteries act independently. Individual batteries do not communicate or share information.

Why choose SimpliPhi’s Lithium Batteries?

SimpliPhi has a lot going for them as well. As I mentioned before, their small and mid-range lithium batteries come in at a lower cost-per-kWh than Discover’s options.

In fact, Discover doesn’t make a 12V lithium battery, but SimpliPhi does. This would be your go-to battery for mobile use, like powering your RV or boat, or small remote applications like security systems or any equipment requiring a 12 volt power source.

SimpliPhi is more competitive in the 24V territory as well. We sell their 24V lithium battery at $1 per Wh, while Discover’s is $1.15 per Wh of capacity. These batteries might be an appropriate choice for small cottages, cabins and tiny homes.

Recommended product: SimpliPhi 3.5 kWh 24V Lithium battery

The rule of thumb is that SimpliPhi shines in applications that don’t require a lot of output. If you need to power lights and charge your phone in a small hunting cabin, we would likely recommend SimpliPhi to save you some money with no real downside.

(It could be a different story for something like a workshop, where you run power tools that demand high power output.)

For small to mid-range applications without intense peak demand, SimpliPhi’s battery sizes are a bit more flexible, and the prices a little bit better.

Discover vs. SimpliPhi: The Verdict

We lean toward Discover for large-scale systems because they’re more space efficient and easier to wire. SimpliPhi has more cost-effective midrange options, and they make a 12V battery, which Discover doesn’t offer.

As far as reliability and reputation go, both companies are solid. Discover has been making batteries since the 1950s, but they are the more recent arrival to the lithium battery space.

SimpliPhi was founded in 2002 with an exclusive focus on lithium battery storage. What they lack in longevity, they make up with laser-focused research and development efforts in the premium lithium battery market. They have quickly earned their reputation as a high-end battery manufacturer.

You can’t go wrong with either product, and we recommend both brands with full confidence.

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What are the Best Solar Batteries? (Updated For 2019)

What are the Best Solar Batteries? (Updated For 2019)

What are the best solar batteries on the market in 2019?

Without a battery bank, you won’t be able to store energy generated by your system. If you’re tied to the grid, no battery means no backup power when the utility grid suffers an outage. If you live off-grid, your system simply won’t work at all.

Batteries are crucial to keep your system running. So what are the best solar batteries on the market?

Since you’re busy, we’ll put our recommendations up front. Keep reading for a breakdown on where each battery shines:

Best Overall Battery for Off-Grid Homes

Best Value Battery for
Off-Grid Homes

Best Battery for
Off-Grid Vacation Homes

Best Battery Backup for Grid-Tied Systems

Best Battery for Storing and Reselling Energy

Best Battery for RV, Marine, Small Off-Grid

What Are The Different Types Of Batteries?

To understand why we chose the above batteries, let’s review what the different types of batteries are. When selecting a battery for your solar system, you have three options: flooded lead-acid, sealed lead-acid, and lithium batteries.

Flooded Lead Acid Batteries

Lead-acid batteries have been used for the last 150 years. These batteries are affordable and about 99% recyclable. They are easy to get rid of at the end of their lifespan.

There are two types of lead-acid batteries: flooded and sealed.

Flooded lead-acid (FLA) batteries are designed to handle daily charge cycling. They do emit gas as a byproduct, so they must be ventilated properly.

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They also require regular maintenance. The plates of every cell in the battery must be submerged in water to function properly (which is why they are called “flooded” batteries). You’ll need to add water every 1 to 3 months to keep the plates submerged. It’s smart to check on them once a month.

FLA batteries are ideal for people who prefer to be hands-on with their system. They’re the most affordable option, but require occasional upkeep to work properly.

Sealed Lead-Acid Batteries

If you won’t be around to perform regular check-ups on your battery, sealed lead-acid batteries are a better option. These batteries are spill-proof and non-hazardous. There are two types of sealed lead-acid batteries with fairly similar characteristics: AGM (absorbent glass mat) and gel.

Sealed batteries are a self-contained system. They don’t need to be refilled with water, like flooded batteries. For that reason, they work well at properties that aren’t occupied full-time, like an off-grid vacation cabin you visit once or twice a year. Sealed batteries won’t self-discharge as fast if they sit idle for extended periods of time while you’re away.

Lithium Batteries

Finally, lithium batteries are a newer technology that hit the market in the 1970s. They are common in laptops and cellphones, but have become more popular in the renewable energy space lately.

Lithium batteries are more expensive, but there are several benefits to justify the higher price tag:

  • Longer lifespan
  • No maintenance
  • More efficient power usage
  • More usable storage capacity (deeper discharges)
  • No off-gassing / ventilation

Best Solar Batteries of 2019: Our Recommendations

So what’s the best battery for your system?

Picking the right battery depends on a combination of factors like application, budget, and expectations for upkeep (like regular maintenance and replacement interval). Your living situation will determine the smartest battery choice for your project.

Here’s our breakdown of the best batteries for a wide variety of situations:

Best Battery for Off-Grid Homes (Overall)

If you live in an off-grid home full time, you need a battery that can keep up with your power demands on a daily basis.

Our recommendation for the best overall battery for off-grid homes is the Discover 48V Lithium battery. It has a long lifespan and affords flexibility if you want to expand your system down the road.

Lithium batteries are a premium storage option. They have a longer lifespan and charge faster than other battery types. And because they can handle deeper discharges, you need less overall capacity than you would with a comparable lead acid battery bank.

They also make it easier to expand your system over time. Let’s say you add a new well pump to your property down the line. With lead-acid batteries, it can be difficult or even impossible to expand your battery bank, depending on the age and how they are wired.

That’s not the case with lithium batteries. More batteries can be added over time, because each battery operates independently with its own internal Battery Management System (BMS).

Lithium batteries can handle extended periods of time without being recharged. This situation would actually damage lead acid batteries because they need to be recharged every day, and will be damaged after several days without a full charge.

That’s why the Discover 48V Lithium battery is our pick for the best overall battery for daily off-grid use.

Best Battery for Off-Grid Homes (Best Value)

Looking for a more cost-effective option? The best value battery for off-grid systems is the Crown CR430 flooded lead-acid battery.

People who live the off-grid lifestyle tend to be more comfortable with hands-on DIY projects. If you don’t mind doing the occasional tune-up on your battery bank, the CR430 is an excellent option.

The 430 amp-hour capacity can’t be beat for the price, and Crown is a reliable American manufacturer (they show up on this list 4 times for a reason). CR430s are built in Fremont, Ohio at Crown’s advanced manufacturing plant.

Best Battery For Off-Grid Vacation Homes

What if you have an off-grid vacation home that you don’t visit on a regular basis? You want a battery that doesn’t require regular maintenance, since you’ll only be on site a few times a year.

In these cases, a sealed AGM battery is the best option. Our recommendation is the 415Ah FullRiver DC400-6. The lower capacity is fine because you don’t need year-round storage. We also skipped out on the premium lithium option, because it’s overkill for a system that will only be used a few times a year.

These batteries are relatively inexpensive, so you don’t have to make a huge investment into a property where you won’t be spending that much time.

The Best Batteries For Living Grid-Tied With Battery Backup

If you have a grid-tied system with battery backup for emergencies, you won’t need a battery with a tremendous amount of storage power. It will only see use when your power goes out, and hopefully that doesn’t happen more than once a year.

Similar to the previous section, you want a battery that doesn’t require maintenance – it should simply work in the rare cases you need it. For that reason, we recommend the same battery as above: the FullRiver DC400-6 with a sealed AGM.

Best Battery For Storing & Selling Energy

In certain areas, the utility company charges more during peak use times – around 4 to 9 pm, when people get home from school and work.

Energy storage allows you to store daytime energy and sell it back to the utility company for a profit.

The goal is to store energy generated during the day, and sell it back in the evening, when rates hit their peak.

For this type of use, we recommend the Discover AES 6.6kWh or the SimpliPhi 3.5 kWh batteries. Both are 48V lithium options. We recommend lithium here because the battery will be cycled more heavily than in a vacation home or battery backup application. The lithium option will have a much longer lifespan and can be just as cost-effective as lead-acid batteries in terms of cost-per-cycle over the life of the battery.

This setup helps protect you from future changes in your utility rates, and is a must if you live in an area with time of use rates (TOU), high demand charges, or no net metering.

The Best Batteries For RV, Marine, Remote Industrial & Small Off-Grid Use

This article has mostly covered residential use cases. But what if you need to power a smaller application, like an RV, boat or small outbuilding on your property?

Let’s say you have a wood shed on your property and want to power it independently. The shed has some lights and wall outlets, but there’s not much else to power. In a situation like this, you just need a compact battery with modest capacity.

For a light use cases like these, we recommend the Crown 6CRV220 sealed AGM battery. This battery was originally designed to power golf carts. As a result, it has a very low profile, but can still withstand deep cycling over a long lifespan.

We’d recommend this battery for tiny homes, boats, and RVs – any application where space is at a premium and you just need to power the essentials. You can also go with the Crown 12CRV110, which is the exact same size and overall capacity.

Battery Math:

The 6CRV220 and 12CRV110 have the exact same size and overall capacity.

6 Volts x 220 amp hours = 1320 watt hours

12 volts x 110 amp hours = 1320 watt hours

This is also our pick for remote industrial applications. It can power small-scale industrial equipment in remote areas not accessible by power lines. Common applications include lighting, pumps, traffic signs and monitoring equipment.

No matter what kind of off-grid system you’re looking for, your battery bank is a key component. Visit our deep cycle battery page to learn more, or check out our battery banks to find a pre-packaged solution.

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Going Off-Grid? Please Don’t Make the Same Battery Mistake I Did.

Going Off-Grid? Please Don’t Make the Same Battery Mistake I Did.

I have always been interested in renewable energy, but when I moved into my grandma’s old cabin in Mendocino, CA, it was the last thing on my mind.

Yes, with the cabin came a small off-grid solar setup, but I was more concerned with abstract concepts like “peace” and “beauty.”

So at first, I was happy with the single 12-volt battery I had. It forced me to live a simple life without a bunch of electronics—always a good thing.

With the limited power available I was able to use my laptop, a few lights, a small speaker, and a phone charger. There was no cell service, so my phone never died, and I used kerosene lamps to read most nights.

It turned out to be one of the best experiences of my life.

But eventually, I was ready to upgrade my battery bank—mostly for the experience.

However, I had no idea where to start.

My first thought was, “This can’t be that hard.”

I quickly realized it was more complicated than I thought.

One of the first things I learned: it is so important to have an understanding of how lead-acid batteries work before messing around with a battery bank’s wiring.

So I asked around for information, found some basic solar books (mostly outdated books from the local library), and used my phone to research batteries when I was closer to town and had cell service.

I ended up purchasing a couple of cheap marine or “deep cycle” batteries from the local hardware store on the recommendation of a new employee.

I realize now he probably didn’t know the difference between car batteries and the marine batteries they carried… but neither did I at the time, so fair enough. (A car battery’s power is measured in cranking amps, because the battery is designed to offer bursts of energy to start a vehicle—rather than slow discharge needed to run appliances.)

Luckily my limited research helped me decide on the marine batteries, which are designed to have a longer reserve capacity than car batteries.

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All that meant in my case, however, was that it took me longer to destroy them.

Knowing what I do now, I’m a little embarrassed to say that I was nowhere near ready to install a battery bank—no matter how small this setup was. Here’s where I went wrong.

The failure happened because I didn’t know the difference between a series connection and a parallel connection.

Diagram showing series wiring versus parellel wiring
Series Circuit Wiring Vs. Parallel Circuit Wiring

In a series circuit, the current through each of the components is the same, and the voltage across the circuit is the sum of the voltages across each component.

Christmas lights are a good example of series wiring. If one light stops working, it blocks the power to the rest of the lights that come after in that circuit.

In a parallel circuit, the voltage across each of the components is the same, and the total current is the sum of the currents through each component.

When hooked up in parallel, each light will have its own path to the power source. If one light goes out, the rest will stay on since they are hooked up independently.

In short, series wiring increases the voltage but the amps stay the same. And parallel wiring increases the amperage but the volts stay the same.

And when I got the two new batteries in place, I had no idea what to do.

Now remember, I was working with just one 12 volt battery before, and now I have two 12 volt batteries, which created 24 volts when wired in series.

It’s also important to remember that my inverter (the heart of the system) operates on a 12 volt battery bank. So I’m limited to 12 volts for my battery system.

But wait, you say. You now have a 24 volt battery bank and a 12 volt inverter, that can’t work. Well, yes and no.

The way I wired it, which was in series, was of course wrong. And that’s because I was running a 12 volt inverter with a 24 volt battery bank.

What I should have done was wired the batteries in parallel at 12 volts, allowing my 12 volt inverter to play nice with my battery bank.

Diagram showing the original, wrong, and right way Ricky should have wired his batteries
Ricky’s Mistake: Wiring Two 12v Batteries in a Series with a 12v Inverter.

On the flip side, I could have bought a new inverter that was 24 volt rated and would have been fine running with two 12 volt batteries in series (totaling 24 volts), but that would have cost me a lot more to upgrade, when all I had to do was wire my batteries correctly.

I’m still not sure if I caused any damage to my solar equipment. I would be surprised if you told me I didn’t.

My grandma warned me that maybe I shouldn’t attempt to upgrade my system, but of course I didn’t listen. Luckily, she seems to be a firm believer in learning through experience… So the time and money spent were not a total loss in her eyes. (Or maybe she was just trying to make me feel better about destroying her stuff…).

After this experience, I decided to pursue some real education in solar installation.

And I won’t lie—my inspiration came from wanting to make things right at the cabin. (Not to mention wanting to prove to myself that I could figure it out.)

My solar disaster was 100% my fault. And although my grandma has never expressed frustration over the “battery-turned-paperweight incident,” I am sure she would appreciate a more thought out and educated approach to make things right again.

That brings me to Wholesale Solar. I have always had an interest in finding a career path in some sort of industry that supported sustainable living, with solar at the top of that list.

I’ve worked in biodynamic farms in the mountains of Mendocino. I’ve also given water conservation a go with a sustainable plumbing company building rainwater collection systems and gray water gardens in Sonoma.

And as a part of that job I noticed that at every beautiful job site there was a solar array.

I was actively taking classes and pursuing my career, but I’m happy (and lucky) to say I fell into the Wholesale Solar team by chance.

I started working here in July of 2016, and eventually found my way into the technical support department. Which is funny—because I often help folks going through the same kind of failed experiment I did.

Solar takes a lot of time, patience, and effort to install and maintain. That’s something I learned the hard way, and something I hope to teach our customers.

I have so much respect for our customers after battling a tricky installation myself, and I am so grateful to finally be in a position to not only help my grandma, but also many other off-the-grid enthusiasts trying to live in an independent paradise.

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SolarTech TV: How to Program Your Power Center

SolarTech TV: How to Program Your Power Center

SolarTech TV is back, ya’ll!

If you missed Josh the Tech Guy’s how-tos that make some of the most complex solar tech look easy, you’re in luck! Making complex tech look simple is his specialty: if you call in for our solar tech support, it’s Josh you’re going to be talking to. And if you’ve talked to him before, you know you’re in good hands.

In this edition, Josh walks you through how to program a Magnum Power Center. If you’ve got an off-grid system from Wholesale Solar, chances are you’re going to need to learn how to program the Magnum inverter, battery monitor kit, AC input amperage, and the Midnite Classic charge controller included in the pre-wired Power Center designed by Wholesale Solar’s expert techs.

Ready? Let’s get started:

Click here to learn more about the Power Center featured in this video!

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Ask Wholesale Solar: Which Batteries Are Right For Me?

Ask Wholesale Solar: Which Batteries Are Right For Me?

There are a lot of reasons folks make the decision to go solar. More and more, that decision involves including an element of backup power, which is stored using batteries.  But which batteries are right for which solar project? Which batteries should you use if you’re running your whole home off-grid? What about for a small cabin that you only visit once in a while? Which batteries are best if you’re adding the security of backup power to your grid-tied home? And how does emerging technology like the Tesla Powerwall compare with other new energy storage technologies?

Get an expert perspective on all of this, and learn about the newest battery technologies, in this latest video in the Ask Wholesale Solar series.

Solar design tech Jeremy A. discusses the differences between the most common types of batteries used to store energy from your solar array, including lead-acid batteries and sealed AGM batteries, and  goes over emerging technology such as lithium ion batteries like the Tesla Powerwall and aqueous ion batteries.

Do YOU have a question you’d like to Ask Wholesale Solar? Ask away in the comments and your question could be featured in a future Ask Wholesale Solar video!

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