Are Lithium Ion Batteries Safe To Use For Solar? [Dos And Don’ts]

Lithium battery technology has completely altered the landscape of modern power storage.

With over 95% efficiency, a compact form factor, less weight, stacked energy density, long overall cycle life, and super fast charging, lithium ion batteries eclipse the competition.

As such, the commercial solar power industry has wrapped itself around this technology and all but adopted it as the go-to solar energy storage solution.

At first, this seems like a perfectly reasonable plan, as the benefits speak for themselves, but is there a catch to this seemingly spectacular technology?

That’s exactly what I’ll be discussing in today’s post. Are lithium ion batteries everything they’re pegged to be, or are they as problematic as the batteries they replaced?

Why You’re Concerned

You’re likely here because you heard a few home truths about lithium ion technology, that there is indeed a catch, a trade-off for all the benefits it brings to the table.

It’s fairly common knowledge that although lithium batteries are leagues ahead of their less efficient counterparts, there’s one area in which they’re lagging… stability.

It’s true that lithium battery technology is technically the least stable of the modern battery blueprints, liable to overheat, and on rare occasions, catch fire or explode.

Being thermal issues, it’s no surprise that solar nuts are particularly worried about the possibility of a battery going haywire, as the sun is of course the most prolific source of heat in our solar system.

But this isn’t to say that all lithium batteries are a fire hazard, or that you should throw your lithium-powered phone in the trash immediately.

The situation is a little more complex than stating lithium = bad. In fact, that simply wouldn’t be true.

Let’s discuss the matter in more detail.

What Is Thermal Runaway & Why Are Lithium Batteries Susceptible?

Some lithium batteries utilize a flammable organic electrolyte in their cells to store and manage power.

Combine this with intense energy density, and there’s some tension at play.

Energy density means higher temperatures, temperatures that get even hotter in the event of physical damage, high ambient temperatures, or electrical mishaps such as overcharge and short-circuiting.

The excess heat can facilitate an exothermic chemical reaction. Thermal runaway occurs when this initial reaction has a knock-on effect on adjacent cells.

This isn’t just a problem because the battery breaks, but because the organic electrolyte is vaporized, thereby pressurizing the battery casing.

Once the pressure overcomes the strength of the casing, it ruptures, releasing the toxic, flammable gasses from within.

How incendiary the rupture is depends on the size of the battery, charge, and the type of casing. For example, a battery might be fitted with a pressure release valve which will nullify most of the hazard.

Softer cases will also reduce the severity of the breach.

If the casing is able to release pressure before it builds, the rupture may just involve a bit of dark smoke, but it gets incrementally worse as the casing gets stronger.

It could be a flare-style burn, all the way through to an explosion.

Product Defects

Product defects due to manufacturing errors are another leading cause of thermal runaway in lithium ion batteries.

This is why, in most instances, buying cheaper lithium batteries is a mistake, as they’ll be made up of poor quality components and will be subject to less stringent quality control procedures.

Should You Be Concerned?

I know that sounds scary, but, for the most part, you have nothing to be concerned about when using lithium ion batteries to harness your solar power.

Rumors of their instability remain from early in their development, but things have changed since the advent of the initial technology.

Lithium Ion Has Become An Umbrella Term

These days, there are a good deal of lithium battery technologies that use the same general power storage process, but they go about it in different ways, and despite their differences, we and the companies who sell them simply refer to them as lithium ion.

Other technologies that fall into this category include…

• Lithium iron phosphate (LiFePO4)
• Lithium cobalt oxide (LiCoO²)
• Lithium manganese oxide (LMO)

Of these technologies, LiFePO4 is the most recent and by far the highest performing of the lot, and it’s safer too!

LiFePO4

Where previous lithium ion technologies were combustible, LiFePO4 is not. Granted, in extreme conditions, there are still absolutely risks of using lithium iron phosphate technology, but the same is true of any power storage device.

It’s not just the primary technology that makes a lot of modern lithium ion batteries safe devices; some companies will integrate safety protocols in order to reduce the risk of thermal runaway to an even further degree.

Some may, for example, utilize seals that activate when a cell destabilizes, preventing the domino effect that is thermal runaway.

Others may have overcharge and short-circuit protection, keeping thermals from getting out of hand on the electrical front.

It’s also worth mentioning that this battery type is a lot more durable in general, meaning that it’s not at the same risk of damage from physical impacts.

Are Lithium Ion Batteries Safe For Solar?

A good quality lithium ion battery will make the perfect pairing for your solar home, or indeed your portable solar setup.

As long as they’re properly installed on your property by a professional, the risk involved is slim to none, and you’ll be getting the highest-performing battery technology currently available for residential applications.

The Dos And Don’ts Of LiFePO4 Solar Battery Maintenance

Before we go our separate ways, let’s take a look at how you look at a few hot tips on LiFePO4 solar battery maintenance and safety.

Hire A Pro

If you know what you’re doing, by all means, install your lithium ion battery into your home or mobile system yourself, but if you’re not sure if you’re up to the task, don’t risk it.

Call in a professional and have them install your battery perfectly.

Use The Right Charger

LiFePO4 batteries have a unique charging process that requires a unique charger, so be sure you’re combining the correct components in your solar setup, otherwise, you may damage that pricey lithium battery of yours.

Proper Storage

A cool dry storage place is perfect for lithium ion batteries, and as they have such a low self-discharge rate, they can be stored for a long time before they reach low capacity.

That said, it’s recommended that before storing your LiFePO4 batteries for any extended period, you should charge them to at least the 60% mark, just to ensure they don’t get too low which can be stressful for lithium ion technology.

They won’t burst into flames if they get too low or anything like that, but it will reduce their overall cycle life.

Invest In A Charge Controller

A charge controller regulates the flow of power from your solar panels so your battery always receives a uniform voltage.

You can think of this as over and undercharge protection, both of which can diminish battery service life.

Stay Aware Of The Temperature

LiFePO4 batteries have a robust temperature sweet spot, but it still pays not to get too sloppy where thermals are involved.

Keep your batteries between 41 and 104° F (5–40° C).

Follow The 20/90 Rule

Lithium batteries don’t like extremes. They dislike being completely full and completely empty, so it’s best to follow the 20/90 rule.

• Never let your battery fall below 20% capacity.
• Never let your battery exceed 90% capacity.

Final Thoughts

While lithium battery technology had something of a rocky start, LiFePO4 batteries are absolutely safe to incorporate into your home or mobile solar setup.

They’re actually the best batteries for the job in a number of ways.

So, what are you waiting for? Grab one today!