According to foreign media reports, although lithium-ion batteries are more efficient to use, their cost is somewhat high. How to find a balance between common materials and efficiency? - Ordinary old salt seems to be able to meet this condition. Recently, from King Abdullah University of Science and Technology (KAUST) has found a way to make 'disordered' graphene, which can improve the formulation of sodium-ion batteries.
Although sodium ions may not be as powerful as lithium ions, they can win in both quantity and cost. The anode material, which is commonly used in lithium-ion batteries, is also very cheap, but unfortunately it is difficult to grasp than lithium. Ionic large sodium ions. In the past, scientists solved this problem by carbonizing oak leaves or filling the crumpled graphene balls at the anode.
The KASUT team has adopted a similar approach. Although this disordered graphite called hard carbon can solve the problem, it is necessary to get the temperature to 1000 degrees Celsius in order to get it. In this regard, the researchers have come up with a simpler one. Approach - use laser to create disordered graphene.
First, KAUST researchers applied a layer of polyimide and urea to a copper foil, which was then 'carbonized' with a strong laser to turn it into graphene. In addition, the researchers are still Nitrogen was used in the process. After about 13% of nitrogen, the research team finally got 3D graphene with more conductivity, increased atomic spacing and direct binding to copper.
The team found that when this material is used as the anode of a sodium-ion battery, the battery efficiency of the device is higher and the capacity is greater than that of a carbon-based anode.
