Choosing The Best Battery For Solar

Home energy storage · Jan 4, 2023

Investing in a solar battery for your home energy storage is always the smarter choice. You’re then able to store energy that your system generates and set it aside for later consumption. If you’re connected to the grid, then having no battery means you won’t have any backup power when an outage occurs. But if you live off-grid, then your system will not work at all without a battery. 

Solar batteries are often referred to as “deep cycle batteries” because of their ability to charge and discharge a significant amount of energy compared to other types of batteries such as car batteries.

When choosing the best battery for your solar storage, there are certain specifications that you need to carefully evaluate first. Below, you will learn about these important criteria.

Comparing Your Options

As you choose between each of your options, you’ll encounter complicated product specifications. These are the criteria you need to evaluate. The most important ones are the battery’s power and capacity ratings, round-trip efficiency, manufacturer, and depth of discharge (DoD).

Power and Capacity

The total amount of electricity that a battery is able to store is its capacity, measured in kilowatt-hours (kWh). For the most part, home solar batteries are meant to be ‘stackable.’ This means that you can get extra capacity by including multiple storage batteries with your solar-plus-storage system. 

Although capacity determines how big your battery is, it does not tell you the amount of electricity it can provide at any given moment. This is why you also need to evaluate the battery’s power. In the context of batteries for solar storage systems, a power rating is measured in kilowatts (kW) and determines how much electricity your battery can deliver at a time. 

Batteries with a low power rating but high capacity can provide a low amount of electricity for a long time. Meanwhile, batteries with a high power rating but low capacity can power your entire home but will only run for a few hours. 

Round-Trip Efficiency

This represents the amount of power that’s available for consumption as a percentage of how much energy it took to store it. For instance, if your battery is fed 5 kWh and you only get 4 kWh of electricity back for use, the battery’s round-trip efficiency is at 80%. Generally, the higher the round-trip efficiency, the more economic value you can get. 


From automotive companies to tech startups, different organizations have started to develop and manufacture battery products. Although significant automotive companies joining the market for energy storage has a long history of manufacturing products, their technology might not be the most revolutionary. Meanwhile, a tech start-up might utilize high-performing technology but have less of a track record to prove the functionality of its products.

Whatever manufacturer you choose depends on your priorities. The warranties associated with the products should also be evaluated before making a decision.

Depth of Discharge (DoD)

Most solar batteries need to have some charge retained all the time because of their chemical composition. Using 100 percent of a battery’s charge will significantly shorten its useful lifespan. 

A battery’s depth of discharge refers to the percentage of the battery’s capacity that has been consumed. Manufacturers will usually specify a maximum DoD to achieve optimal performance. If a 10 kWh battery has a 90 percent DoD, then more than 9 kWh shouldn’t be used before recharging it. A higher DoD allows you to maximize your battery’s capacity.

Warranty and Battery Life

Solar batteries are similar to the batteries of cell phones in that the more you use them, the more their ability to hold a charge decreases. You charge your phone at night so you’re able to use it during the day, and the older your phone gets, the more you notice that its battery isn’t holding as much of a charge as it originally did. For instance, a battery warrantied for 5,000 cycles or 10 years at 70 percent of its original capacity will lose no more than 30 percent of its original ability to store energy by the end of the warranty. 

How long your battery will last is something you should always evaluate before purchasing. The answer to that question depends on the brand of the battery and the amount of capacity it loses over time.

Get the best one at FranklinWH

If you’re looking for the best battery storage, then look no further than at FrankinWH. Its home power system charges from any solar inverter and comes with a 13.6-kilowatt-hour (kWh) battery.

The battery unit is able to output 5,000 watts to 10,000 watts of continuous power and surge for 10 seconds. This amount of power is enough to run a 4-ton AC unit.

Compared to other home batteries available on the market, FranklinWH batteries offer more features and benefits. In its price class, its functionality is second to none with solid technology and the right certifications. 

With FranklinWH’s battery and home energy storage system, you no longer need to worry about suffering outages and living in a powerless home.

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