China remains a major global player in solid-state battery development, holding around 35% of global patents and leading the world in research output growth. Annual publications have surged from just 21 papers in 2015 to over 560 in 2023, with key contributions from institutions such as the Chinese Academy of Sciences and Tsinghua University. These advances are particularly focused on solving critical technical challenges like solid-solid interface engineering, which remains a key barrier to commercialisation.

Despite this scale, the report warns that China’s position is being challenged as other countries accelerate coordinated policy and industrial strategies. Japan still leads in total patent filings at around 37%, compared with China’s 30%, and dominates high-value institutional concentration in the sector.

Patent race highlights uneven global leadership

Global solid-state battery patents have now surpassed 16,000, with China (3,341) and Japan (3,225) effectively neck-and-neck, followed by the United States and South Korea. However, Japan maintains a strong lead in top-tier patent holders, with Japanese and South Korean firms occupying most of the top 30 institutional rankings.

Toyota stands out as the single largest patent holder, accounting for roughly 40% of global solid-state battery intellectual property. By contrast, Chinese companies show a more fragmented patent profile and weaker international deployment, particularly across the US, Europe, and Southeast Asia.

Industrialisation accelerates, but key technical hurdles remain

China’s industry is rapidly moving from research to early-stage commercialisation. Companies such as CATL, BYD, and SVOLT filed more than 500 patents in 2023 alone, while pilot production lines are already operating and small-batch manufacturing is expected around 2027, with broader adoption targeted for 2030.

Recent breakthroughs include prototype cells exceeding 450 Wh/kg energy density and fast-charging capabilities, alongside advances in sulfide, oxide, and polymer electrolyte systems. However, no single technical pathway has emerged as dominant, and major challenges remain, including lithium dendrite formation, interface instability, and long-term failure mechanisms.

At the same time, China is formalising the sector with its first national solid-state battery standard under consultation, aiming to classify liquid, hybrid, and fully solid-state technologies as the industry moves toward industrial scale.