The State Administration for Market Regulation has recently issued the national standard titled ‘Test Methods for In-Use Power Batteries of Electric Vehicles,’ which is set to officially take effect on March 1, 2027. This standard is designed for the evaluation of power batteries currently in use in electric vehicles, encompassing a range of situations including battery hazard assessment, transactions involving second-hand vehicles, and functional performance testing. It details the general testing conditions applicable to in-use power batteries, lists inspection criteria such as appearance, airtightness, insulation, and thermal management systems, and offers methods for estimating key metrics like available capacity retention rate, voltage, and internal resistance consistency. The establishment of this standard fills the gap in a unified methodology for in-use testing of power batteries in new energy vehicles. It boosts transparency regarding battery technical specifications and transactional details, protects consumer interests, and bolsters the standardized functioning of the new energy vehicle aftermarket. Through standardized testing, it promotes high-quality and sustainable growth within the industry.