- Flexible Armour: A Revolution in Solid State Battery Design
- Impressive Results Under Testing
- A Leap Toward the Future of Electric Mobility
China continues to strengthen its leadership in battery innovation as a team of scientists announced the development of a flexible protective layer that dramatically improves the durability of solid state batteries under freezing temperatures and heavy use. Published in Nature on October 29, 2025, this groundbreaking research is the result of collaboration between Tsinghua University, Shenzhen International Graduate School, and Tianjin University. The project aims to enhance the stability and performance of solid state batteries under extreme conditions, paving the way for the next generation of electric vehicles worldwide.
Flexible Armour: A Revolution in Solid State Battery Design
Solid state batteries are widely regarded as the next evolution of electric vehicle power systems. They offer higher energy density and improved safety compared to liquid batteries, which can overheat or catch fire. However, their main challenge lies in cracking during fast charging or in freezing weather, which leads to structural damage and performance loss.
To overcome this issue, the Chinese research team developed a new flexible armour layer that coats the surface of the battery, reinforcing its internal structure and resistance to stress.
The concept focuses on improving the solid electrolyte interphase (SEI), a normally hard and brittle region prone to fractures. Instead of making it stiffer, the researchers engineered it to be more ductile, allowing it to bend slightly without breaking.
Key Features of the New Layer:
Uses advanced silver based compounds such as silver sulfide (Ag₂S) and silver fluoride (AgF).
Offers flexibility and compression resistance without breaking the battery’s internal structure.
Enables smooth movement of lithium ions, maintaining internal balance and stability.
Prevents uneven lithium buildup during charging, extending battery lifespan.
Enhances the battery’s ability to withstand low temperatures and high pressure.
With this innovative design, the new protective layer acts as a hybrid shield combining strength and elasticity, ensuring the battery maintains stable performance and energy efficiency even in the harshest environmental conditions.
Impressive Results Under Testing
The solid state batteries equipped with the flexible armor layer underwent a series of rigorous experiments, showing remarkable performance in both stability and durability. These results position the innovation as one of the most significant advancements in energy storage technology in recent years.
Performance results:
Operated for more than 4,500 hours of continuous use without any decline in performance.
Maintained stable operation for over 7,000 hours at –30°C, a temperature that typically causes conventional batteries to fail.
Featured a layered combination of soft and rigid materials to reduce internal stress and prevent cracking.
Ensured an even distribution of lithium ions during charging and discharging, improving overall efficiency and lifespan.
The project was led by Professors Feiyu Kang and Yanbing He from Tsinghua University, alongside Quanhong Yang from Tianjin University, and supported by the National Natural Science Foundation of China, the National Key R&D Program, and the Shenzhen Science and Technology Innovation Plan.
A Leap Toward the Future of Electric Mobility
Although the technology is still in the research phase, it represents a crucial step toward developing more efficient and durable solid state batteries capable of withstanding extreme environments, paving the way for their integration into next generation electric vehicles.
In GCC markets, where temperatures vary drastically between daytime heat and cool desert nights, this battery design could be an ideal solution for electric vehicles, offering consistent performance and enhanced safety.
Experts believe that such breakthroughs could accelerate the production of premium electric cars equipped with longer lasting and more sustainable batteries, positioning China as a leader in global clean energy innovation.
Through this milestone, Chinese universities and research institutions reaffirm their ability to overcome technical challenges that have long limited the commercialization of solid state batteries, marking a decisive move toward a safer and more efficient electric future.
