BYD's Blade batteries are heading underground: FinDreams partners to electrify industrial rail locomotives

FinDreams Battery, BYD's cell-making subsidiary, and Changsha Fusheng Technology formalized a cooperation agreement on September 7 at BYD's Pingshan campus in Shenzhen. The goal is "automotive-grade" Blade battery systems for rail vehicles that never touch the public network: shunting locomotives and site-transport machines working in mines, industrial plants and railway yards.

The two companies split the work along their strengths. FinDreams will cover cell research, development and production, while Changsha Fusheng — a specialist in integrated energy systems for fixed-site equipment — will marry the packs to the battery-management and electronic-control hardware needed for rail operations. Neither side revealed the deal's value, expected supply volumes, locomotive specs or when commercial service might begin.

The agreement extends a recent push by FinDreams into off-highway electrification. Just two days earlier, on September 5, the battery maker struck a similar deal with Zero Carbon Engine Technology Group to explore projects in Mongolia, including electric mining trucks. BYD is also no stranger to heavy-duty applications: in June it delivered 100 T31 electric dump trucks to Shenzhen construction firms, each carrying a 424 kWh Blade pack, and its Q3 electric tractor — shown in Hunan in April alongside agreements for 150 new-energy heavy trucks — is set to debut at IAA in Germany later this year.

Diversifying into new segments comes as BYD's grip on China's EV battery market loosens. From January to July 2026 the company installed 72 GWh domestically, an 18% share that fell 13% year on year, while rival CATL grew 22% to 186 GWh and 46% of the market. That dominance is pushing automakers to hedge: Li Auto is moving to in-house-designed cells built by Sunwoda, in which it is investing 2.65 billion yuan, following Xpeng's earlier retreat from CATL.