Written By Suzanne Stougie
Most EVs are decked out with high-performance lithium-ion (Li-ion) batteries. These are the kind of batteries you'll already have lying around the house - in your laptop, mobile phone, cordless drill - only bigger. Your car will have a whole host of Li-ion batteries, bundled together in a neat, lightweight package, making it possible to power a whole car over hundreds of miles.
Tesla Model S Chargeport, Photographed by Paul Sladen in the Tesla Showroom Frankfurt from Wikimedia Commons
Over time, Li-ion batteries lose some of their oomph, though. This is partly unavoidable: a normal part of the battery's life span. EV manufacturers give their all to make your car's battery last a long time, with most brands offering some kind of warranty against excessive battery loss. At Ford, it's 8 years or 100,000 miles, for instance, with Tesla, Nissan and many other brands offering similar cover. Overall, its predicted that today's car batteries will last an impressive 10 to 20 years, with an average capacity loss of only 1.6 to 2.3% per year. That's really not bad at all.

Still, there are some factors that accelerate your battery's degradation somewhat. Want to keep your EV's battery in a fit state? Here's what you can try at home:
  • Prevent an 'extreme state of charge'. In other words, don't let your battery power go all the way up to 100% or all the way down to 0%. It's much better to keep your car charged between 20 and 80% at all times. Most, but not all electric cars have a built-in buffer that takes care of this for you. If yours doesn't, make sure you unplug it before it hits 81%.
  • Stick to the 20% to 80% rule described above even when your car is standing around for a few days (or weeks). Going away for a longer period of time? Hook your EV up to a timed charger.
  • Save draining the battery completely or topping it up to full for emergencies (or very long trips) only.
  • If range anxiety is not something you are worried about, try topping up your car just enough for the next day before removing the charger.
  • Keep fast-charging to a minimum. Slow is the way to go. Level 3 charging (also called DC Fast Charging) puts extra stress your electric car's battery, making it age prematurely.
  • Avoid extreme temperatures - high heat will negatively impact you EV battery's health. Newer cars have heat management systems that reduce the impact of the outside, but on a hot day, this will drain the battery of a car that's not plugged into the power grid. So, either plug in or park in the shade.
  • Allow your car to cool down before charging.
  • Keep your car's software up to date.