Automotive semi-solid-state battery
With the announcement of SAIC MOTOR's MG4 semi-solid-state battery vehicle delivery plan in December, this technology, considered by the industry as the "optimal transition solution between liquid and fully solid-state batteries," is demonstrating its unique value for the construction machinery sector. Compared to traditional liquid lithium-ion batteries, what are the core advantages of semi-solid-state batteries? Let's explore them together.
MG4 car equipped with a semi-solid-state battery
Compared to traditional liquid lithium-ion batteries, semi-solid-state batteries use a gel-type electrolyte, reducing the risk of electrolyte leakage by over 90%. MG's test data shows that its semi-solid-state battery maintains a zero-fire record even under extreme conditions such as puncture and compression—crucial for construction vehicles operating in harsh environments. The SAIC MOTOR MG4 construction vehicle, soon to be delivered, has passed -30°C extreme cold testing, with a battery performance retention rate exceeding 80%.
Semi-solid-state batteries achieve an energy density exceeding 300Wh/kg, a 20%-30% improvement over traditional batteries. This means that a battery pack of the same size can extend the range of construction vehicles by 100-150 km, significantly reducing charging frequency in the field. Mass-produced models from companies like CATL have achieved a range of over 1000 km.
Through optimized composite electrode materials and an intelligent BMS system, semi-solid-state batteries exhibit performance fluctuations of less than 15% in temperatures ranging from -40°C to 60°C. This is of disruptive value for construction vehicles operating in harsh environments such as mines and polar regions. Data from Baidu Research Institute shows that its high-temperature stability is three times that of liquid batteries.
With a cycle life of over 2000 cycles and a degradation rate only one-third that of liquid batteries, combined with 80% fast-charging in 12 minutes (ClearTech Energy test data), the total cost of ownership can be reduced by 40%. The SAIC MOTOR MG4 semi-solid-state version has lowered its price to around 100,000 yuan, accelerating commercialization.
Semi-solid-state batteries use recyclable polymer electrolytes, reducing carbon emissions during production by 35% compared to traditional processes. Some manufacturers have established "battery banks" where retired batteries can be repurposed for energy storage in construction machinery. This closed-loop system complies with the EU's latest carbon tariff requirements.
As of September 2025, six major Chinese construction equipment manufacturers had initiated compatibility testing for semi-solid-state batteries. BAIC FOTON launched the industry's first semi-solid-state battery truck, marking a new phase in the electrification of commercial vehicles. SAIC MOTOR confirmed that the MG4 construction vehicle equipped with this technology will be delivered in December, signifying the industry's entry into the mass-production stage. CATL's silicon-doped lithium-ion battery technology is expected to increase energy density from 170Wh/kg to 350Wh/kg, making it more attractive for construction equipment with demanding range requirements. The industry predicts that the global market for semi-solid-state batteries in construction equipment will exceed $8 billion by 2026.
Currently, semi-solid-state batteries still face challenges, such as a temporary decline in energy density (e.g., the Lantu Chasing Light's range is 20% less than the liquid-type version), mainly due to reduced ion conductivity caused by the mixed liquid-solid electrolyte. However, companies like E-Fune Technology, through its intelligent BMS system optimization strategy, and CATL, with its electrode material improvement plan, are gradually overcoming this bottleneck. For construction equipment users, it is recommended to prioritize battery systems that have undergone rigorous heavy-duty testing, such as the 6400-cycle test performed by AiYike Battery.
