The technology, which replaces the battery's chemical solution with a new substance with gel-like polymerizability, can be mass-produced for immediate application to China's booming electric vehicle industry, the researchers said.
The research, led by Professor Yu Le and Associate Professor Li Nianwu from Beijing University of Chemical Technology, was published last week in the peer-reviewed journal Advanced Functional Materials.
Since battery capacity decreases with repeated charging and discharging, one of the key indicators of battery life is capacity retention, which is the ratio of discharge capacity to initial discharge capacity after a specific cycle, the report said.
The researchers conducted a series of tests to measure the capacity retention performance of the new battery.
Li Nianwu said: "We performed a 100% deep discharge on this battery. This process actually damages the life cycle of the battery, but it can effectively expose the problem."
"After 300 cycles of charging and discharging at 100% depth, our battery capacity remained at 92%, compared to 30% for conventional batteries," he explained.
The researchers say the achievement is encouraging. It shows that this new type of battery has a significantly longer lifespan than batteries made with state-of-the-art technology.
In their paper, they say the battery could be used in industry scenarios such as electric vehicle batteries or drones to extend its lifespan.
Yu Le and Li Nianwu developed a semi-solid and semi-liquid gel polymer electrolyte as a new filling material for lithium batteries.
The researchers say that the gel polymer electrolyte is in an intermediate state, so it can combine the advantages of conductivity and safety.
The report states that the gel polymer electrolyte is composed of nano-sized silica and nanoparticles as inorganic fillers, in which the nanofibers act as a matrix for the nanoparticles. The researchers also used a jelly-like material to fill in the gaps between the pores.
Nanosilica and nanoparticles stimulate the movement of charged ions in lithium and chemicals, thus increasing conductivity. The researchers say that the micro-nano structures filled with gel-like materials with high porosity can promote free ion migration.
The nanoparticles also improve the fire resistance of gelled polymer electrolytes because they are not flammable.
Nanofibers, on the other hand, have high porosity, which supports and enhances the flexibility of the internal structure of the battery.
All these features make the new electrolyte more stable and have additional properties, the researchers say.
Li Nianwu said: "China is leading the development of high-energy-density batteries, and BYD and CATL are very good in this field. But battery explosions and safety issues still receive global attention."
He added: "Many researchers are taking different paths to the problem, offering a variety of options, including replacing electrolytes with solid ceramics or nanocomposites. Our gel polymer electrolyte is one of those options."