Ultra-fast charging and EV battery aging remain key battery health topics. Credit: CGTN Understand China EV’s Market Real-time notifications when critical EV data is released All important data in one place 2,000,000+ data points Become a member China has disclosed details on the implementation requirements of the recommended national standard GB/T 46991.1-2025, which specifies the accuracy and durability of electric vehicle battery health display systems for light-duty passenger vehicles. According to a CCTV News report published on August 2, the document defines limits for differences between dashboard-displayed battery available energy status and measured results, while establishing battery durability reference levels based on vehicle age and mileage. GB/T 46991.1-2025 was developed under the guidance of the Ministry of Industry and Information Technology (MIIT) and the Standardisation Administration of China (SAC), with technical input from a drafting expert group led by Yu Yang. It applies to light-duty passenger electric vehicles and is classified as a recommended national standard rather than a mandatory safety regulation. Display error capped at 5% A key requirement covers the accuracy of battery health information displayed to drivers. The document defines State of Available Energy (SOCE) as the ratio between a battery’s current available energy and the available energy of a new vehicle battery. Unlike State of Charge (SOC), which indicates remaining energy during vehicle operation, SOCE is intended to reflect long-term battery capacity retention. Under the requirement, the relative deviation between the SOCE value displayed by a vehicle and the physically measured value must not exceed 5%, meaning the displayed value must not differ from the measured value by more than 5%. The requirement establishes a reference for comparing displayed battery health information with measured battery capacity. Virtual Mileage GB/T 46991.1-2025 also addresses battery energy consumption outside normal driving conditions. It requires non-driving discharge, including energy used by vehicle systems while parked or operating accessories, to be converted into an equivalent Virtual Mileage. Virtual Mileage converts non-driving energy consumption into an equivalent distance based on a vehicle’s energy consumption rate. The displayed value must remain within a 3% relative deviation from the measured result. The publicly disclosed summary does not provide detailed testing conditions for individual scenarios, including different accessory loads or stationary power consumption situations. Durability targets The document establishes minimum State of Available Energy retention levels for light-duty passenger electric vehicles based on age and accumulated mileage: Vehicle AgeMileage BaselineMinimum SOCE Requirement5 years100,000 km≥82%8 years160,000 km≥75%10 years200,000 km≥70% The figures represent the remaining available energy compared with the vehicle’s original factory-available energy. For example, a battery with an initial available energy capacity of 100 kWh would need to retain at least 82 kWh after five years and 100,000 km under the evaluation requirements. The disclosed information applies to light-duty passenger vehicles. It does not indicate whether similar thresholds extend to commercial vehicles, buses, trucks, or two-wheelers. Regulatory context The disclosure comes as China continues developing standards covering EV battery quality, recycling, safety, and lifecycle management. GB/T 46991.1-2025 focuses on battery health measurement, display accuracy, and durability evaluation. It is separate from mandatory safety standards, such as GB 38031-2025, which establishes mandatory battery safety requirements, including provisions on thermal runaway. As a recommended national standard, GB/T 46991.1-2025 focuses on evaluation criteria and does not establish publicly disclosed administrative penalties, mandatory recalls, or enforcement actions for vehicles exceeding the specified deviation limits. Battery condition has become an important factor in warranty discussions, used vehicle evaluations, and long-term ownership decisions. Concerns over how charging habits, including frequent fast charging, may affect battery ageing have also increased attention on accurate battery condition assessment. Differences between displayed battery information and actual battery condition have highlighted the need for consistent measurement and evaluation methods. Used EV impact Battery condition is a factor in used-electric-vehicle evaluations, warranty discussions, and lifecycle assessments. By defining measurement methods for SOCE accuracy, Virtual Mileage calculation, and battery durability benchmarks, GB/T 46991.1-2025 provides a common reference for evaluating battery condition. The effect on used EV pricing, warranty disputes, and consumer evaluation practices will depend on how automakers, testing organisations, and the wider market apply the requirements over time. Most important news in your inbox. Recaps · scheduled All you need, in one email. Instant alerts · real-time Ping me when an article goes live. 0 of 27 topics selected Bundle into one email per day — instead of one email per article No spam · Unsubscribe with one click · Change settings anytime
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