SAIC has launched the MG4, its first model equipped with an LMO semi-solid-state battery, through its MG sub-brand, marking the inaugural commercial deployment of semi-solid-state batteries.

On 5 August, SAIC unveiled its first mass-produced semi-solid-state power battery through its subsidiary brand, MG. Officially described as a "semi-solid-state battery with novel manganese-based cathode material," its structure was confirmed as mainly lithium manganate (LMO), as seen in spinel-structure scanning electron microscope (SEM) images displayed at the launch event. Supplied by Qingtao Energy, the cell's energy density is estimated at approximately 180Wh/kg, comparable to regular lithium iron phosphate (LFP) batteries.   

Compared to LFP batteries, SAIC's LMO semi-solid-state variant demonstrates improved safety and low-temperature performance while maintaining similar energy density. However, it exhibits marginally inferior charge rates and cycle life, consistent with LMO's intrinsic properties. The cathode material likely incorporates nickel cobalt manganese (NCM) dopants for functional viability. The electrolyte system aligns with Qingtao's first-generation technology, utilising oxide or oxide-polymer composite with liquid phase content reduced below 5%.

Material costs for this LMO-plus-oxide configuration may exceed ternary batteries when accounting for process maturity, yet its implementation in the RMB100,000 (US$13,900) MG4 model suggests significant cost advantages. This commercial viability is further supported by China's RMB1Bn (US$139M) targeted subsidy program for solid-state batteries.  

Fundamentally, this MG4 battery launch is more a symbolic show than carrying practical significance. The product offers negligible advantages over LFP alternatives, functionally resembling an enhanced sodium-ion battery iteration. It primarily serves as a testbed for dry electrode manufacturing processes, with its low-temperature performance attributed to the LMO cathode rather than the semi-solid-state architecture.

The actual technological advancement lies in achieving extended cycle life under sub-5% liquid phase conditions. The truly noteworthy development remains Qingtao's planned next-generation lithium-rich manganese-based halide/sulfide all-solid-state batteries.  

Pre-sales for the semi-solid-state configuration commence in September 2025 with deliveries targeted for the end of the year. This parallels SAIC's earlier 133kWh semi-solid-state announcement for its IM brand, which never reached commercial production.

Even if Qingtao Energy possesses the technical capability to supply lithium manganate (LMO) batteries to SAIC, the system's poor overall commercial performance will ultimately constrain installation volumes. The LMO architecture holds limited potential within China's battery market landscape.