China’s GAC Group claims it has successfully designed an all-solid-state battery using high energy cathode material – likely nickel-manganese oxide (NMC) or lithium manganese oxide (LMO) – what it calls a “sponge-silicon negative electrode”, and an all-solid-state electrolyte, though exact details of the material used within said electrolyte were lacking from the announcement. GAC aims to deploy the batteries within GAC AION’s Hyper vehicle line by 2026, with the batteries entering into mass-production this year. GAC claims its battery’s energy density is in excess of 400 Wh/kg, a 50% and 52% increase in gravimetric and volumetric energy density relative to state-of-the-art liquid electrolyte lithium cells respectively. GAC’s claim to be entering mass-production of all-solid-state batteries sets it apart from WeLion,…