Ionic Liquids Enhance Solid State Lithium Metal Batteries

May, 2022 - By SMI

Researchers found that using ionic liquid in cathode material seals structural voids and enhances contact with a solid electrolyte in batteries with lithium metal

A team of scientists at Tokyo Metropolitan University, Japan is focused on finding a solution for common problem of next-generation lithium metal batteries, and are searching for a significant solution in salty liquid reducing the resistance in key components of batteries. The team developed a prototype battery that has impressively enhanced stability and this could lead to new ways for battery chemistry with considerable potential.

As pure lithium metal provides extremely high density, it is considered as a significantly promising prospect for energy storage and using it instead of copper and graphite improves performance and battery life of electronic devices. However, lithium ion batteries have limitations such as stability issues. In this new research, the team of scientists approached a new way of solving instability issue in these batteries by creating a quasi-solid-state electrode to use it in such batteries. The team worked on solid electrolyte known as LLZO that interfaces in the lithium metal anodes, however causes maximum resistance during interface with traditional cathodes. The team added ionic liquid with room-temperature to reduce resistance and improve contact between the cathode and the solid ceramic electrolyte.

Furthermore, the team found that using ionic liquid (salt in liquid form) on lithium cobalt oxide cathode resulted into filled voids in the interface and dramatically reduced any type of resistance. Moreover, it also boosted ion transport due to ionic conductivity of this ionic liquid. The prototype battery with this new quasi-solid-state cathode exhibited significant stability and maintained its 80% capacity for 100 cycles of charge and discharge at 140˚F temperature. Making this technology commercial requires a lot more work. However, the new discovery could be new base for solid-state lithium metal batteries.