Rules for solid-state battery set

China has released the world's first national draft standard on solid-state batteries, which experts said will help speed up the nascent sector's development in the world's largest vehicle market.

Such batteries are expected to see small-batch production in 2026-27, with large-scale commercialization expected by 2030, said CITIC Securities.

The draft, released by the National Technical Committee of Auto Standardization in late December, aims to define key technical concepts and to unify testing criteria for the sector.

There is currently no unified international standard for automotive solid-state batteries, although global demand for solidstate and hybrid solid-liquid batteries is expected to exceed 700 gigawatt-hours by 2030, with solid-state batteries accounting for 200 GWh, according to CITIC Securities projections.

China's move can be seen as a strategic step that will not only regulate domestic industrial growth but also provide the country with a first-mover advantage in shaping global technical rules for the new energy sector, said analysts. A key feature of the draft is a tighter classification system, which groups batteries into three categories — liquid, hybrid solid-liquid and solid-state.

Under this framework, the marketing term "semi-solid-state" is not used as a standard category, which may help automakers and consumers have a clearer understanding of battery characteristics. In addition, the document further classifies solid-state batteries by electrolyte type and application area.

Another focus is that the draft sets a stricter threshold for identifying solid-state batteries. It says the weight loss rate should be no more than 0.5 percent. The metric compares the weight lost after vacuum drying under specified conditions with the sample's initial weight, and a lower figure indicates fewer liquid components within the battery.

The drafting team said that solid-state batteries should contain no liquid electrolyte components, but some solid electrolyte materials may decompose under test conditions and cause limited weight loss. Based on validation results, a weight loss rate below 0.5 percent was established as the proposed threshold.

An industry standard issued in May 2025 by the China Society of Automotive Engineers uses a limit of below 1 percent, highlighting the stricter requirement in the proposed national standard.

Experts noted that more stringent standards are essential for refining the market environment and fostering industrial growth.

Unified terminology and assessment criteria will help eliminate the hype surrounding pseudo solid-state batteries and resolve conceptual confusion within the industry, thereby establishing a solid foundation for supply chain collaboration and market standardization.

Moreover, more rigorous benchmarks will compel companies to pursue genuine technological breakthroughs rather than relying on marketing labels, they said.

wangyuchen@chinadaily.com.cn