The most vital component of any electric car is the battery, and the battery's health can significantly impact the car's range and value. The U.S. state of California is now laying out rules for the batteries used in EVs.
The California Air Resources Board adopted new rules this week that will block the sale of new gas-powered cars in the state by 2035, with a gradual ramp-up starting in 2026. The ruling also includes new requirements for the batteries used in electric cars, to ensure they "can be full replacements to gasoline vehicles, hold their market value for owners, and that used car buyers are getting a quality vehicle that will not pollute."
Starting with electric cars with a model year of 2026 or later (which should start appearing in 2025), the car must maintain at least 70% of its original range for 10 years or 150,000 miles. That will increase to 80% of the original range for 2030 model year cars. The Air Resources Board is also setting requirements for individual battery packs -- by model year 2026, battery packs must retain 70% of their energy for eight years or 100,000 miles, which increases to 75% by model year 2031. Finally, powertrain components must be under warranty for at least three years or 50,000 miles.
The rules aim to address one of the most common problems with electric cars -- batteries wearing out too quickly. Gas and hybrid cars generally retain their range throughout their entire functional lives, but the batteries in electric cars slowly lose maximum capacity, just like the batteries in other electronics. As the battery dies, the maximum range drops, and the value of the car decreases.
There aren't many countries or states that have enacted rules about battery life in electric cars. The United Nations and World Forum for Harmonization of Vehicle Regulations proposed a rule in 2021 that would require batteries maintain 80% capacity over 5 years or the first 100,000 kms (about 62,000 miles), but it has not been widely adopted. The United States doesn't have any federal legislation about EV battery health, but the recently-passed Inflation Reduction Act will require a certain percentage of minerals used in batteries to originate in North America for the car, in order to receive a federal tax rebate.
Source: California Air Resources Board