3 Simple Rules For Lithium Batteries In EVs

How can I get the most out of my electric vehicle battery for the longest? - I get this question a lot, and the answer is actually really simple. Follow these rules, and your battery will very likely be fine for years to come!

1) Never charge when the battery pack temperature is sub-zero

We should never charge lithium batteries when the battery pack temperature is sub-zero (e.g. below 0 celsius or 32 fahrenheit). If the Battery Management System (BMS) doesn't stop charging at this temperature, this WILL destroy your battery pack.

Lithium battery cells will not take charge when at sub-zero temperatures, and will instead crystallize, and expand the cell physically. Best case, your battery won't work. Worst case, the battery pack punctures and violently catches fire.

That being said, many EVs has a battery pack heating system that heats up the battery before charging. If your EV is equipped with such a system, charging at sub-zero temperatures is unproblematic.

2) Store your battery close to 50%

Storing batteries long-term is always a bit of a pain. Generally keeping your pack as close to 50% as possible is best to keep the battery healthy for the longest (talking about years into its lifecycle). Many people use the 20-80% rule. The 20-80 rule means you don't let the SoC (state of charge) drop below 20% and you don't charge above 80%.

Always store your battery between 20% and 80% State of charge.

3) Don't be scared of going outside of the 20-80 rule when using your battery

Following the 20-80% rule does NOT mean you cannot run your battery to single digits, or charge to 100% if you plan on riding longer rides. It's mostly a guideline for what to do when storing the bike over time. Actually, charging your battery to 100% every once in a while is a good idea to keep the cells properly balanced.

Does this actually matter?

These simple rules will get you the most of your battery pack for the longest. But generally, EVs and other lithium packs come with Battery Management Systems (BMS) that doesn't let you charge to the actual 100% or deplete to the actual 0% levels anyways.

The most important part is to use your electric vehicle or equipment and enjoy it. Your battery will likely last for years no matter what. If they don't, that's usually covered under some kind of warranty.

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