GoKawiilUS start-ups race China in sodium-ion battery push, chromium safety questioned
American start-ups including Unigrid are developing sodium-ion batteries aiming for fully US-sourced supply chains, unlike lithium-ion batteries where China dominates materials and manufacturing. Unigrid's founder Tan says the company currently sources its sodium-ion cells from China but could shift to US suppliers later. Scientists have raised concerns that chromium-3 used in Unigrid's cathode could form toxic chromium-6 under certain conditions, though Tan and one outside researcher say the risk is manageable and the battery has passed safety certification.