How Long Will A Solar Lithium Battery Last? [And Which Should You Buy?]

The lithium ion battery blueprint has completely changed the residential solar energy game!

Smaller, lighter, longer serving, and with a higher energy density than the lead-acid standards of old, they’re making solar a more viable option for a lot of enthusiasts and eco-warriors.

With a quality lithium ion battery (or 6) in your green energy arsenal, you’re positioning yourself at the forefront of the practice and maximizing your solar yield, but just how long can you expect your lithium solar battery to last?

These things run the gamut from relatively affordable to astronomically expensive, so it pays to know how many replacements you’ll need over the years.

Let’s take a look at what you can expect in terms of solar lithium battery shelf life.

Lithium Ion Solar Battery: General Shelf Life

Of course, much like any piece of electrical kit, lithium solar batteries are quite varied and can be found at a number of points in the market, meaning quality and shelf life will fluctuate from product to product.

However, generally speaking, as long as you take good care of your lithium solar battery, you can expect to get at least 10 years service out of it, which is pretty great.

Considering solar panels last for between 20 and 30 years before their productivity drops to impractical levels, as long as you’re developing a single battery system, you may only need to invest in 2 solar lithium batteries.

And if your solar panels do reach that third decade, your third battery replacement will continue to serve you if you decide to eventually replace the panels.

There are also examples of quality lithium ion batteries lasting up to 15 years before they kick the bucket, meaning even if your panels lasted a full 30 years, you’d only ever need one replacement.

How Does This Compare With Lead-Acid Solar Batteries?

Don’t get me wrong, there’s still a booming market for lead-acid solar batteries, and I think they can be a smart choice in certain scenarios, but there’s no arguing with the clear superiority of the lithium ion blueprint.

Take the average lead-acid shelf life, for instance — You’re looking at 3–5 years.

That’s not to say there aren’t some truly beefy lead-acid batteries out there that can live as long as 10 years, but the pricing for these batteries overlaps the price tags on some pretty great lithium tech.

Lithium Ion Solar Battery Maintenance

Another reason you’d be wise to choose lithium over lead-acid is the general lack of care they need to perform at the top of their game.

Lead-acid batteries require a pretty hectic maintenance schedule, but with lithium batteries, you really only need to do two things.

Thermal Protection

Modern lithium batteries are built to withstand some pretty intense temperatures, but if you’re expecting particularly extreme weather, establishing some form of thermal protection will ensure they last for as long as possible.

Discharge Protection

Lithium batteries aren’t too keen on power extremes. They find being at both full capacity or completely spent incredibly stressful, which reduces their service life.

Keeping them above 20% and only charging them to 90% capacity is the best way to help them live long and happy lives.

Lithium Ion Solar Battery Cycle Life

We’ve established that the typical lithium ion solar battery will last at least 10 years with normal use.

In fact, most will be warrantied for that entire period, which certainly inspires consumer confidence and peace of mind. However, with batteries, it’s not just shelf life that we need to be aware of, but the cycle life too.

The cycle life of a battery is simply the number of times it can be recharged from its max DoD before it becomes unsuitable for the intended task.

For those wondering, DoD stands for depth of discharge, and it’s the lowest threshold a battery can safely be discharged to. For most quality lithium batteries, DoD is around the 95% mark.

Lower quality lithium batteries can be cycled around 500 times, but most will go strong for between 2000 and 10,000 charge cycles.

With two means of expiration (cycles and shelf life), all lithium batteries come with dual warranties that cover both eventualities, but only once overall.

Once you hit the warrantied cycles or the warrantied duration expires, the entire warranty is null and void.

Solar Lithium Battery: A Buyer’s Guide

In this guide, I’ll be taking you through a few key considerations when shopping around for lithium ion solar batteries, before suggesting a few of the best in the biz, so without further ado, let’s get started.

Capacity Vs. Count

The first question you need to ask yourself is how much power storage you’ll need. You can do this by adding up the loads of all the appliances and systems you plan on powering with your solar battery.

Then, you have to decide if you’re going to try and find a single battery that can handle the loads you have in mind or if you’re going to purchase multiple smaller units that, combined, can shoulder the total load.

The irritating part of this stage is that most manufacturers only give you the Amp hours, rather than the Kilowatt hours of a battery, but you can figure it out with the following formula:

Ah x V ÷ 1000 = kWh

So, let’s say that your prospective battery is rated for 200 Ah at 12 Volts; our sum would look a little something like this…

200 (Ah) x 12 (V) = 2400 ÷ 1000 = 2.4 kWh.

Charge Cycles & DoD

As discussed earlier, the charge cycles of a battery are the number of times it can be discharged to a certain DoD and then recharged. On both counts (cycles and DoD), the higher the better.

Shelf Life & Warranty

For a lithium ion solar battery, I’d disregard anything warrantied for less than 5 years of use, since they typically last a lot longer — we’re talking 10 years +.

Temperature Rating

Lithium solar batteries generally have broad thermal tolerance, but it can vary from product to product, so if you live in a particularly hot or cold climate, be sure to check temperature ratings before you buy.

BMS (Battery Management System)

A good battery management system is great for a portable lithium solar battery, as it will protect against overcharge and optimize charge rates, but for a stationary home system, a charge controller will do a lot of the heavy lifting.

Lithium Ion Solar Battery Suggestions

Lossigy Deep Cycle LiFePO4 Solar Battery — High quality batteries for serious power.

• 4000–7000 cycles
• 10-year shelf life
• 5-year worry-free warranty
• 300 Ah

Ampere Time Deep Cycle LiFePO4 200 Ah Solar Battery — Top-of-the-market solar muscle.

• 4000+ cycles at 100% DoD
• 24 V
• 200 Ah
• Expandable to 800 Ah

Ampere Time Deep Cycle LiFePO4 Solar Battery — Best bang for buck lithium solar battery.

• 4000+ cycles
• 10-year shelf life
• Built-in BMS
• 100 Ah

Final Thoughts

This has been your crash course in solar lithium battery service life, with a few buying suggestions tacked on for good measure.

As long as you keep what we discussed here in mind when choosing your first lithium battery, you’ll snag the perfect one for your solar goals.