Lithium-ion batteries: our tips for extending their life

Lithium-ion batteries have become the benchmark for powering 100% electric vehicles, with improved range and shorter charging times. But what about their lifespan and range, and how can they be maintained? Read ViaMichelin's advice.
Lithium-ion batteries: our tips for extending their life

How long does a battery last?

The lifespan of a lithium-ion battery is not measured in terms of the number of miles driven but in terms of the number of charge/discharge cycles. However, as most models are designed to withstand between 1000 and 1500 full cycles, it can be estimated that with an average range of around 125 miles, the life of a lithium-ion battery is around 200,000 miles. In general, the warranty established by the manufacturers for an electric vehicle battery is 8 years. But the longevity of a battery also depends on how you use it!

Conditions of ageing

An ageing battery will lose its capacity and require a longer charging time. Several factors influence the life of a lithium-ion battery:

  • Its size: the smaller it is, the shorter its life. A 40 kWh battery requires half as many recharges as a 20 kWh model.
  • Frequency of charging cycles: the more frequently they are charged, the more the battery’s performance and range decrease.
  • Heat: batteries are very sensitive to heat. This can be caused by overheating or by external factors, such as extreme temperatures.

How do I know how long a battery will last?

The life of a battery is determined by its “state of health” (SoH). Expressed as a percentage, this corresponds to the current performance of the battery compared to its initial capacity. If it is 100% for a new model, it is estimated to be between 70 and 80% for a battery at the end of its life. The SoH is a valuable indication of a battery’s condition.

Tip: When buying a second-hand electric vehicle, the SoH is a key indicator of whether or not you are getting a good deal.

What precautions should I take to preserve my battery?

Use your car regularly

Leaving your car idle unnecessarily discharges the battery. Ideally, you should use it every day.

Favour regular recharging

It’s better to charge your car at frequent intervals than to charge it for a long time, as this heats up the battery more.

Good to know: a charge cycle is a full 100% charge. When charged twice from a level of 50%, your battery is only subjected to one cycle.

Stay within the optimum charge level

Staying within a charging window of between 20% and 80% will preserve your battery cells.

Adopt eco-driving

Smooth driving without sudden acceleration and braking helps to preserve the battery.

Wait before recharging the battery

If you have been driving your vehicle, wait until the battery has cooled down to room temperature before recharging.

Slow charging is best, and wait before driving again

Rapid charging increases the risk of overheating. Similarly, do not drive immediately after recharging the battery.

Park in temperature-stable areas

Park your car in the shade in hot weather. Parking in a garage is good practice to avoid subjecting your car to temperatures that are too low or too high.

Limit the use of air conditioning and heating

In general, use functions that put a strain on the vehicle’s battery sparingly.

While electric vehicle batteries have a good life expectancy, driving smoothly and protecting them from heat are good ways to preserve their performance.