How does temperature affect EV charging performance?

An electric car's lithium battery can be charged safely only within a certain temperature range. The battery management systemGlossary · BatteriesBattery Management System (BMS)A system that monitors and manages the performance, health, and charging of batteries. (BMS) monitors it continuously and limits the charging current if the battery is too cold or too hot. In the cold, fast chargingGlossary · BatteriesFast ChargingA charging method that restores battery capacity quickly without damage by controlling current, voltage and temperature. can cause permanent damage to lithium cells, while overheating accelerates their ageing.

The effect is most noticeable with DC chargingGlossary · EV chargingDC ChargingFast charging in which the station converts power to direct current and feeds it straight into the battery, typically at 50 to 350 kW.. A car arriving at a station on a cold winter morning may charge at noticeably less than its maximum power until the battery warms up. With AC charging at home the power is low, so the difference usually goes unnoticed. The charger itself may also reduce its output if it overheats, for example when a wallbox is mounted on a wall in direct summer sun.

Practical tip: many electric cars precondition the battery when you set a fast-charging station as the destination in the navigation system. Where possible, charge right after a drive, when the battery is already warm, and for an outdoor wallbox installation choose a shaded spot.