A Korean research team has successfully developed a technology to make a sponge-like electrode material using graphene and a polymer, leading to a graphene battery. The newly-developed battery is ten times as small as existing ones, but can show the same product performance.
A research team headed by Park Ho-seok, professor of the School of Chemical Engineering at Sungkyunkwan University, announced on Feb. 1 that it has succeeded in developing a very porous graphene aerogel electrode material by combining polyvinyl alcohol and graphene.
Studies on developing high-capacity and rapidly-chargeable batteries are underway worldwide. It is necessary to compress devices in order to supply energy in extreme conditions. However, when existing graphene-based batteries are compressed by 30 percent, product performance suffers owing to the destruction of the inside structure.
After inducing a chemical reaction between polyvinyl alcohol and graphene in a state of solution, the research team was able to develop a graphene aerogel electrode material that is easily compressed and highly durable, thanks to a great number of pores inside. Aerogel, which is called the lightest solid, is a porous ultralight material. An estimated 90 to 99.9 percent of the material is composed of air, and pores smaller than 100 nanometers form a 3D web.
Polyvinyl alcohol is combined between graphenes like tangled thread, and thus when it is compressed with outside pressure, pores of graphene aerogel do not stuck together, according to the research team. The structure of graphene does not damage, either.
When the battery became 10 times smaller using graphene aerogel, its performance was similar to that of existing graphene batteries with the same size. Moreover, it was able to maintain the same product performance after it went through the compression and restoration process for more than 10 million times.
The graphene aerogel electrode material is expected to be utilized in the energy storage equipment of electric cars, mobile devices, and space ships, which have been hard to develop using conventional batteries, due to limits in volume and weight.
The research findings were published online on Dec. 18 in Advanced Functional Materials, a scientific journal published by Wiley-VCH.