How To Pick Out The Best Battery For a Solar Panel System, Battery Bank, or Off-Grid System
Or have you wondered what makes one deep cycle battery better than another? If so, this article will answer these questions and give you specific things to check on before buying your new battery (to ensure you get the most bang for the buck)!
When choosing a battery (or batteries) for your solar panel system, there are 3 categories of batteries which work best. We’ll do this in 2 parts:
Part 1) Instantly compare the three main types of solar batteries (lead acid, saltwater, and lithium). And,
Part 2) Assess the elements of batteries, such as: depth of discharge, power and capacity, efficiency, battery life, and manufacturer.
By the end of this article you will know just how to pick out the best battery to your solar panel system!
So let’s get started…
Part 1) The Three Best Types Of Batteries For Solar Panel Systems: The best type of battery for your solar panel system will depend on what you’re looking for. So the first decision to make is the sort of battery that will fit your system.
Lead acid batteries are the most commonly used rechargeable battery in the world. They’re also one of the longest-used and most dependable batteries in existence. Compared to the other batteries we will discuss in this report; they’re the cheapest option but you trade price for some battery life and depth of discharge. But for homeowners needing lots of storage for a lower price, or whether you are just making the transfer to a solar panel system, lead acid batteries may be an excellent option. They’re the sort of battery we use in most of the battery banks within our solar panel systems.
Saltwater batteries are more expensive than lead acid batteries, but also have a greater lifespan. Unlike lead acid batteries, saltwater batteries are essentially brand new to the industry and remain both somewhat untested and more difficult to come across. Of the three types of batteries, saltwater has the best depth of discharge, so you’ll get the most output per charge before needing to recharge.
Lithium batteries are the most expensive and the longest lasting of the three kinds of solar batteries. Their depth of discharge is less than that of a saltwater battery, but more than that of a lead acid battery. Comparing all three options, the lithium battery may be the highest rated, but also the most expensive. A good example of a lithium battery is the Tesla Powerwall.
Part 2) Compare the elements of batteries. As soon as you’ve chosen the best battery type for your own solar panel or off-grid system (that meets your system’s needs), there are elements to explore to find the ideal battery to your system.
Price is probably one of the more obvious elements. But the old saying,”you get what you pay for” holds true when buying batteries also. In some instances though, certain batteries could be overkill for your system so the most expensive battery may not be the best choice always.
For many systems, a battery will cycle every day, meaning it is going to charge and drain regularly. With each cycle, the battery’s ability to hold the same charge lessens slightly. So one component to consider is the guarantee on the battery which guarantees a specific number of cycles of useful life. But keep in mind that if you use the maintenance and reconditioning methods we teach you in the EZ Battery Reconditioning application, you can extend the life of your batteries.
Depth of Discharge
Length of release is how much you can drain the battery down before needing to recharge the battery without harming its life. Particular solar batteries may be depleted further than others, allowing for more use between charging. Essentially, a battery with a 90% depth of discharge per cycle will provide more battery power per charge than a battery with less.
Ability and Power
Measured in kilowatt hours (kWh), capacity is the amount of energy a battery can store over time. The more capacity a battery has, the more power it can save. Power is how much energy that a battery can provide at a certain moment. A battery with both a high capacity and high power can run a massive system for many hours; a battery with low capacity and higher power can run a large system but only for a brief time.
Efficiency is the amount of energy used compared to the quantity of energy it took to save energy. Batteries require power to charge and efficacy compares the energy taken to charge a battery together with the amount of energy which the charged battery generates. The higher the efficiency, the more cost-effective the battery.
This might not be a component most would consider, but it is something to focus on. As with other technologies, there are both trusted brands and startup brands. A trusted brand comes with known flaws and benefits; a startup brand can perhaps have better technology, but could also have unknown technological issues. Depending on your system needs, you might decide to go with a well-reviewed firm or one that is brand new to the market.