TU-TESL

• 22

According to foreign media reports, a new research carried out by researchers from the Japan National Institute of Materials Science (NIMS) showed that commercial silicon nanoparticles were prepared by spray deposition in solid electrolyte, and then the silicon anode made of such silicon nanoparticles showed excellent electrical properties. This method is a very cost-effective atmospheric technology. The results show that large-scale and low-cost production of high-capacity anode for all solid lithium is possible. In theory, the capacity of silicon is about 4200 MAH / g, about 11 times that of graphite, the common anode active material in commercial lithium-ion batteries. Replacing traditional graphite with silicon can greatly extend the range of electric vehicles. However, in the process of lithium-ion and lithium-ion (battery charging and discharging process), the volume of silicon will change dramatically (increase by about three times), thus preventing its practical application in the battery. In traditional liquid electrolytes, it is necessary to use polymer adhesive to bond the active material particles in the electrode together and make them adhere to the metal current collector. The constant change of silicon volume will lead to the separation of particles, which will lead to the loss of active substances, and then lead to the continuous loss of capacity. In a solid-state battery, the active material is placed between two solid-state components, namely, the solid-state electrolyte isolation layer and the metal current collector. In fact, as NIMS researchers say, the actual area capacity of sputtered pure silicon film is more than 2.2 MAH / cm2, showing good cycle stability and high rate discharge capacity in solid electrolyte. However, it is still a great challenge to realize low-cost and industrial expandable synthetic anode in all solid state lithium battery. NIMS research team has used another synthesis method to achieve high-performance anodes for all solid-state lithium batteries made of commercial silicon nanoparticles. The researchers found that the nanoparticles in solid-state batteries have a unique phenomenon: after lithium, in the limited space between the solid electrolyte isolation layer and the metal current collector, the volume of nanoparticles will expand, the structure will be compacted, and they will obviously accumulate, similar to the nanoparticles prepared by evaporation. Therefore, nanoparticles prepared by spray deposition method can be used for anode to show excellent electrode properties. Spray deposition is a cost-effective atmospheric technology that enables mass production on a large scale. Therefore, such discovery can pave the way for mass production of high capacity anode for all solid state lithium battery at low cost. In order to meet the requirements of electric vehicles, NIMS researchers continue to work hard to improve the cycling capacity of the anode.