Lithium-ion batteries are crucial for powering electric vehicles and storing renewable energy.
However, many people worry about the safety of the liquid electrolytes they currently use.
These liquids can leak harmful chemicals into the environment or even catch fire if they get too hot.
To solve these problems, scientists are exploring solid-state batteries, which replace the liquid with solid materials.
In a recent study published in Solid State Ionics, Shirley Reis and her team from the SENAI Innovation Institute in Electrochemistry, Brazil, found a way to make solid-state batteries safer while maintaining high performance.
Their solution involves using a special mix of ceramic and polymer materials to create a new type of solid electrolyte.
The study is part of a five-year partnership between the institute and the Brazilian Metallurgy and Mining Company (CBMM). Their goal is to use niobium, a material produced by CBMM, to improve the next generation of lithium-ion batteries.
In all batteries, the electrolyte is a key component. It sits between two electrodes and helps ions move back and forth during charging and discharging.
Solid-state batteries have big advantages over traditional ones because they don’t catch fire and can handle higher temperatures.
But there’s a challenge: ceramic electrolytes, though highly conductive and stable, are brittle. On the other hand, polymer electrolytes are flexible but don’t conduct well and aren’t stable at high voltages.
Reis’ team tackled this by blending ceramic and polymer materials into a composite electrolyte. Their mixture included zirconium-doped niobium garnet oxide (a ceramic) and polyethylene oxide (a polymer).
By carefully testing different ratios, they found a balance that offered flexibility, high ionic conductivity, and stability at high voltages. Even after many cycles of charging and discharging, the battery retained much of its original capacity.
The researchers also used a high-nickel cathode, which is known to increase energy density. The results showed that the composite electrolyte can support such advanced materials, making it possible to build batteries with more energy storage.
These findings are significant because the materials used are low-cost and widely available. This makes it easier to scale up production and bring solid-state batteries closer to commercial use.
“The global growth of lithium-ion batteries offers new opportunities to develop better materials,” says Reis. “We hope our results will contribute to creating safer and more powerful batteries for the future.”
If successful, this technology could lead to safer batteries for electric vehicles and renewable energy storage, helping to reduce reliance on fossil fuels and protect the environment.
