CARB proposes new rules for defining EV battery health

Buying a pre-owned EV presents a new concern for buyers to beware of—the health of the vehicle’s battery. All batteries degrade over time, and there’s no simple way for a buyer to know how much of its original range a used EV retains. Some older EVs—notable the air-cooled Nissan LEAF—have poor records in this department.

The California Air Resources Board (CARB) is taking a comprehensive approach to electrification, and its proposed Advanced Clean Cars II framework, which sets an objective of making EVs 80% of new light vehicle sales by 2035, includes provisions for defining EV battery health.

The new rules, which would apply beginning in model year 2026, would require that battery EVs maintain 80% of their certified range for 15 years or 150,000 miles. The regulations would also require a “customer readable state of health metric,” allowing buyers to ascertain the state of health (SOH) of a particular vehicle without the need for any special tool. The vehicle maker would have to clearly specify the SOH percentage that qualifies for warranty repair.

The proposed rules would also require “information disclosure for all propulsion-related components,” and a standardized procedure for reading vehicle diagnostic data such as propulsion-related fault codes. As Green Car Reports sees it, this measure is related to the Right to Repair movement, which Tesla has generally not supported.

David Reichmuth of the Union of Concerned Scientists sees the proposal as a positive both for consumers and the environment. It’s important to ensure that “consumers don’t have concerns over buying a used EV and being able to replace a gasoline vehicle.” And the longer an EV’s useful life, the greater the amount of emissions it will offset.

Consumer Reports also praised CARB’s proposed rules: “CR welcomes the new electric vehicle durability requirements to ensure consumers have access to long-range, long-lasting vehicles.”

CARB will vote on a more detailed version of the proposal later in the year, and will be accepting public comments through June 11, 2021.

Source: CARB via Green Car Reports