How to Maximize the Life of Your Electric Car Battery — Myths, Chemistry and Truths

Today's electric car batteries are robust and built to last the entire life of the car. But as with any technology, your habits can affect how well your battery performs in five or 10 years. Here we find out what applies to charge levels, chemistry and why the manual sometimes says one thing while the research suggests another.

Basic rule 20-80% (for most cars)

For the majority of today's electric cars (those with so-called NMC or NCA batteries, common in Long Range models andperformance cars), the rule of thumb applies to keep the charge level between 20 and 80 percent to everyday life.

Why? Battery cells are subjected to maximum chemical stress when they are crammed or nearly empty. To routinely charge to 100% Accelerates Chemical Aging. Therefore, save the full charge for the days when you really need maximum range.

LFP batteries — the important exception

Do you have a car with LFP battery (lithium iron phosphate, common in “Standard Range” models)? Then you probably read in the manual that you should charge to 100% regularly.

There is an interesting balancing act here. Chemically, it also works. LFP batteries are best not stay at 100%. The reason why manufacturers recommend it anyway involves recalibration and cell balancing. The car's BMS (Battery Management System) system has a hard time knowing exactly how much power is left in an LFP battery unless it is allowed to “hit the ceiling” occasionally.

The smart advice for the LFP: A golden mean supported by modern research is to charge to 80% for your short daily trips, but to make sure to fully charge to 100% sometime a week (or according to the manual's range). This protects the battery chemistry from unnecessary wear, while keeping the car's rangefinder correctly calibrated and the cells balanced.

Heat and speed

Regardless of the type of battery heat battery's worst enemy. Fast charging (DC) runs fast but generates a lot of heat, which wears more on the cells than slow home charging (AC).

See fast charging as a tool for long journeys. In everyday life, the slow charging via charging box is superior — it is gentle, effectively balances the battery and provides the longest life.

Three quick ones to increase the life of your electric car battery:

1. Long-term parking never fully charged

Will the car be stationary for a week at the airport? Leave it at about 50-60%. Standing “parked and crammed” (100%) is harmful to all battery types, especially in hot weather.

2. Preconditioning

Use scheduled departure with the charging cable i. Heating/cooling the battery with mains power saves cycles and gives you longer range.

3. Let the charge take time

AC charging (home charge/destination charge) allows the battery monitoring system to fine-tune the voltage between cells in peace and quiet, which optimizes performance.

By being a little “battery smart” in everyday life, you secure both today's range and tomorrow's second-hand value.