MG’s Semi-Solid-State Battery is a Game Changer for EVs
The electric vehicle (EV) industry has been buzzing with anticipation for the arrival of solid-state battery technology, which promises to revolutionize the way EVs are powered. Now, MG has taken a crucial step forward by introducing a semi-solid-state battery pack in the MG4, unveiled through recent patent photos filed with China’s Ministry of Industry and Information Technology (MIIT). This marks a pivotal moment, not just for MG, but for the entire automotive industry, as it signals that next-generation battery performance is becoming more accessible to the mass market.
Why Semi-Solid-State Battery Matters
Battery technology is often called the "heart" of an EV. Current lithium-ion and lithium iron phosphate (LFP) batteries have powered the rapid growth of electric vehicles, but they come with limitations such as overheating risks, limited energy density, and reduced efficiency in cold weather. Semi-solid-state batteries bridge the gap between traditional lithium-ion and fully solid-state batteries, offering a balance of performance, safety, and cost-effectiveness.
Unlike conventional lithium-ion batteries, which use liquid electrolytes that are prone to leakage and thermal runaway, semi-solid-state batteries incorporate a semi-solid electrolyte. This material is more stable, non-flammable, and capable of withstanding higher thermal stress. The result is improved safety, longer lifespan, and enhanced cold-weather performance which are the key factors that can encourage broader adoption of EVs.
MG4 with Semi-Solid-State Battery: A Breakthrough Move
While most automakers are reserving cutting-edge battery technologies for luxury or flagship EVs, MG has chosen to introduce semi-solid-state technology in the affordable MG4 hatchback. This is a bold and strategic decision.
- Affordability: Standard MG4 models are already available for pre-order in China, starting at approximately $10,000 (73,800 yuan). Although the semi-solid-state version will be priced higher, the competitive production scale of the MG4 could still make it one of the most cost-effective EVs with advanced battery tech. Pricing details are expected in September 2025, with deliveries planned before year-end.
- Performance: The new MG4 EV will feature a 120 kW (161 hp) front-mounted motor. Standard versions come with LFP batteries of 42.8 kWh and 53.9 kWh, offering ranges of 437 km (272 miles) and 530 km (330 miles) respectively. The specifications for the semi-solid-state version are yet to be revealed, but industry expectations suggest significantly improved range and faster charging times.
- Design: Inspired by MG’s Cyberster roadster, the MG4 sports a modern look with a Cyberster-inspired front fascia, illuminated MG badge, sporty petal-shaped wheels, and Union Jack-style arrow taillights. It measures 4395 mm long, 1842 mm wide, and 1551 mm tall, with a 2750 mm wheelbase, providing ample interior space.
- Interior: The hatchback features a 15.6-inch floating infotainment screen, a SAIC-Oppo co-developed system, and Cell-to-Body (CTB) battery integration, maximizing both cabin comfort and battery safety.
The Technology Behind the Battery
The MG4’s semi-solid-state battery is developed by Suzhou Qingtao Power Technology, a pioneer in next-generation lithium-ion solutions. Unlike traditional LFP cells, this manganese-based lithium-ion pack incorporates a semi-solid electrolyte that contains just 5% liquid.
Key Benefits of Semi-Solid-State Batteries:
- Higher Energy Density: Semi-solid-state batteries can deliver 30–40% higher energy density compared to conventional LFP packs. This means more range with less battery weight which is crucial for long-distance travel and vehicle efficiency.
- Faster Charging: Charging times are expected to improve significantly. A typical 10% to 80% charge could be completed 25-35% faster, reducing a 40-minute charging session to under 30 minutes.
- Improved Safety: Traditional lithium-ion batteries face risks of overheating during thermal runaway events. Semi-solid-state batteries dramatically reduce these risks. In rigorous testing, including three-directional needle penetration, the MG4’s battery showed no smoke or fire — a major safety leap.
- Better Cold-Weather Performance: One of the biggest complaints among EV owners is reduced efficiency in cold climates. Semi-solid electrolytes handle temperature fluctuations better, ensuring reliable performance year-round.
- Longer Lifespan: Semi-solid-state batteries tolerate more frequent full discharge cycles without significant degradation. This translates into a longer overall battery life and lower total ownership cost for EV drivers.
Semi-Solid-State vs Solid-State: What’s the Difference?
It’s important to clarify that semi-solid-state batteries are not the same as fully solid-state designs.
- Semi-Solid-State: Contains a gel-like or partially solid electrolyte with a small amount of liquid (around 5%). This enhances stability and safety while retaining some characteristics of traditional lithium-ion batteries.
- Solid-State: Uses a fully solid electrolyte and eliminates the need for an anode, significantly reducing weight and further improving safety. Solid-state batteries are considered the “holy grail” of EV energy storage, but they remain challenging and expensive to mass-produce.
In short, semi-solid-state is a half-step toward solid-state, offering many of its advantages but with fewer manufacturing hurdles.
Why MG’s Move is a Game Changer
The EV market has long awaited a manufacturer that could bring next-gen battery technology to the masses. Most automakers, including Toyota and BMW, have announced solid-state plans, but these are typically positioned for premium models launching years down the line.
By contrast, MG is introducing semi-solid-state tech in a budget-friendly hatchback that competes directly in the mass market. This could accelerate adoption in several ways:
- Accessibility: Affordable pricing makes advanced battery tech available to more consumers.
- Scalability: Mass production of MG4 semi-solid-state packs could push down costs across the industry.
- Consumer Trust: Enhanced safety features and better cold-weather performance can eliminate common barriers to EV ownership.
If successful, MG could set a new benchmark for the EV industry, similar to how Tesla disrupted the market with long-range electric sedans.
Looking Ahead: The Future of EV Batteries
The future of EVs is deeply tied to battery innovation. Semi-solid-state technology is not the final destination but a critical step toward fully solid-state batteries, which promise unmatched safety, ultra-fast charging, and ranges exceeding 600–800 km on a single charge.
Until then, semi-solid-state designs like MG’s offer a realistic, near-term solution that bridges today’s EVs and tomorrow’s breakthroughs. If MG’s rollout succeeds, it could spark an industry-wide shift, forcing competitors to accelerate their own adoption of next-gen battery technologies.
The MG4 with semi-solid-state battery technology represents far more than just another new EV model. It’s a statement of intent, a declaration that advanced energy storage solutions are no longer confined to high-end vehicles or distant promises. By placing this innovation in an affordable, mass-market car, MG has redefined what consumers can expect from an EV in 2025 and beyond.
The MG4 semi-solid-state EV is shaping up to be a game-changer, offering greater safety, faster charging, better cold-weather performance, and longer life, all at a price point that could undercut many rivals. With deliveries set to begin by the end of 2025, the global EV industry may be on the cusp of its next great leap forward.
