China Tests 620-Mile Range Semi-Solid EV Battery

The 1,000 km (620-mile) range barrier is being broken by several Chinese automakers using semi-solid-state batteries. NIO's ET7 sedan, equipped with a 150 kWh pack from WeLion New Energy Technology, demonstrated a range of 1,044 km in a 14-hour livestreamed test. This 150 kWh pack has a cell-level energy density of 360 Wh/kg and weighs only 20 kg more than NIO's 100 kWh liquid-ion battery. IM Motors, a joint venture including SAIC and Alibaba, is also in the game with its L6 sedan. Its "Light Year" semi-solid-state battery, co-developed with Qingtao Energy, has a capacity of over 123 kWh and enables a 1,002 km range under CLTC conditions. The L6 features a quasi-900V architecture that allows for ultra-fast charging, adding 400 km of range in just 12 minutes. This push isn't limited to a single company. Researchers at Nankai University, working with China Auto New Energy Battery Technology, have tested a 142 kWh semi-solid-state battery pack with a system-level energy density of 288 Wh/kg. The cells themselves reportedly exceed 500 Wh/kg, a significant jump from the roughly 350 Wh/kg limit of current liquid lithium-ion batteries. The world's largest battery manufacturer, CATL, is also heavily invested, planning mass production of semi-solid batteries by 2026. The company has already launched a "condensed-phase" battery with an energy density of 500 Wh/kg, which has been deployed in a 4-ton electric aircraft, showcasing the technology's potential beyond cars. For robotics and drones, this leap in energy density is critical. Solid-state and semi-solid-state designs offer higher energy storage per kilogram, which directly translates to longer operational times and increased payload capacity for unmanned systems. The solid electrolyte also enhances safety by reducing the risk of fire and leakage associated with liquid electrolytes, a crucial factor for aerial and autonomous applications.