Engadget Outlines Charging Habits That Can Degrade EV Batteries

The report said the simplest habit to drop is charging to 100 percent every time. Full charges may be unavoidable for remote job sites or cross-country trips, but lithium iron phosphate batteries should be fully topped up only once a week if possible, while nickel manganese cobalt systems should generally stay around 80 to 90 percent. Modern EVs and chargers allow fixed percentage caps. When uncertain, Engadget recommended keeping the battery between 20 and 80 percent, because running very low is also harmful and charging usually slows sharply beyond 80 percent.

Temperature matters as well. Cold makes charging inefficient and can require preconditioning, but high heat near 104 Fahrenheit, or 40 Celsius, can actively accelerate degradation. The report suggested early morning or overnight charging, charging in a garage and letting a car settle after a long trip before plugging in. It also advised avoiding Level 3, or DC fast, chargers unless the driver is on the road, low on charge and cannot wait for a Level 2 charger. Although long-term degradation from Level 3 charging appears minor, the report said it is not insignificant because the process generates waste heat.

To further stretch battery health, Engadget said drivers should minimize hard driving. EVs typically have between 1,000 and 2,000 full charge cycles, and fewer charging sessions can help the battery retain capacity. It recommended cruise control, speed limits and efficient routes. It also advised sheltering the vehicle, since batteries have an optimal resting temperature and a car closer to 68 to 86 Fahrenheit, or 20 to 30 Celsius, will spend less energy on preconditioning. Parking in shade or out of wind can help, and in hot climates a reflective windshield visor may be useful.

The report said drivers should not be rigid about the guidelines. EVs are designed to be driven and to withstand most use, and charging to 100 percent twice a week will not collapse battery health. If owners consistently push the limits, noticeable mileage loss is likely to take several years.