EV Battery Health

Keeping yourself parked? Three things to know about EV battery health.

While EV drivers work-from-home, homeschool-at-home, and everything-else-from-home, your electric ride is probably looking lonely sitting in your driveway or garage. With your electric vehicle parked for extended times, what’s the best strategy for not damaging the battery?

Both internal-combustion and electric cars are designed to be driven regularly, which is why leaving them stationary for long periods of time can cause problems. Turns out, it just requires knowing a few key pieces of information about your car, and an occasional drive around the block.


1. The 12-Volt Accessory Battery

In addition to your EV’s main battery, there’s probably a 12-volt accessory battery, too—yes, even if you get a Tesla Model Y. While the main battery pack provides power to drive the car, the 12-volt battery often powers other electrical components, including battery-management systems and telematics. That means it’s very likely to get drained if a car is parked for too long,  preventing your EV from starting up. 


2. The 20 to 80 Percent Charge Rule

The lithium-ion cells in the battery packs of most modern EVs don’t like to be kept at a full state of charge or a very low state of charge for long periods of time. If your car allows for preset charging to a specific state of charge, it’s best to set that to roughly half battery capacity, rather than a full recharge—and limit any charging sessions to an 80% ceiling, if your car permits that. Some cars may also have “sleep” or “transport” modes for long periods of inactivity.


3. To Plug or Not to Plug?

It’s best to follow manufacturer recommendations on whether to keep an EV plugged in or not. Many automakers recommend keeping cars plugged in so power can be provided to run battery cooling or heating systems. Otherwise, the car will have to draw power from the battery pack to run these systems. Nissan, on the other hand, recommends leaving a LEAF unplugged so it can enter a “deep sleep” mode. If left unplugged, many EV battery packs can drain by as little as a few percent of total battery capacity per month.


Read the full discussion on greencarreports.com.