When it comes to graphene, it is definitely a star material. It attracted the attention of scientists because of its ultra-thin, stable characteristics. Currently, researchers have developed graphene-based solar screens, high-performance image sensors, and new transistors. The latest news shows that this magical material can also play an active role in the battery field.
According to the Daily Scientific website, Australian scientists have used graphene to create a denser supercapacitor, which has a lifetime comparable to that of conventional batteries and has an energy density that is 12 times that of existing supercapacitors and can be widely used. Renewable energy storage, portable electronic devices, and electric vehicles. Related research was published in the latest issue of Science.
Supercapacitors generally consist of porous carbon filled with a liquid electrolyte that is responsible for the transfer of charge. The biggest advantage of current supercapacitors is their long life and quick charging, but their shortcomings are also very obvious, that is, the energy density is relatively low, generally only 5-8 hours watts/liter, which means that super capacitors can be very large or Must be charged regularly.
Now, the research team led by Li Dan, a materials engineering professor at Monash University, has developed a new supercapacitor with an energy density of 60 kW/l. Its energy density can be about 12 times that of current supercapacitors. And what is used is exactly graphene. Because graphene has very stable chemical properties and excellent electrical conductivity.
The Li Dan team used a previously developed adaptive graphene gel film to fabricate dense electrodes in new supercapacitors. In addition, they use liquid electrolytes, the conductors in traditional supercapacitors, to control the spacing between subnanometer-scale graphene flakes. This liquid electrolyte serves two purposes: to maintain a fine pitch between the graphene sheets and to conduct electricity.
Many unnecessary large “holes” with traditional “hard” porous carbon waste a lot of space. Li Dan’s team used electrodes made of graphene sheets to maximize the energy density without sacrificing porosity. . The methods they use are similar to those used in the traditional papermaking process, which means that this method is easy to upgrade and also has a cost advantage.
