New-energy vehicles, military industry, aerospace, special electric tools, large-scale energy storage and other major national needs all put forward very high requirements for the safety, energy density, service life and working temperature range of batteries. All-solid-state lithium-ion batteries (ASSLIB) can satisfy all above requirements, and have been recognized as the next-generation core energy storage technology.
All solid-state batteries with lithium metal or silicon anodes are the most promising candidates for achieving high energy density and high safety, but lithium dendrites or volume expansion issues are the challenges that constrain their performance. Fan Wu’s team developed a hard-carbon-stabilized lithium-silicon alloy anode, which is composed of a dense continuum formed by the fusion of silicon and a 3D ion-electron conductive network with plastically-deformed lithium-rich phases. This expands the active region and reduces stress concentration, thereby improving electrode dynamics and mechanical stability, achieving long cycle life (30000 cycles), large current density (155mA/cm2), high discharge rate (100C) and high surface capacity (20 mAh/cm2), reaching the highest level in solid-state battery industry all over the world.
Wu’s team also invented a one-step gas-phase synthesis method of sulfide solid electrolytes(SEs) with ultra-high moisture stability and ionic conductivity. This is the first time in the R&D history of sulfide SEs that a gas-phase synthesis method was proposed and one-step preparation of air-stable sulfide SEs in air was realized. This greatly simplifies the preparation process and solves the problems in the production of sulfide SE materials. Addressing the strict environmental requirements in transportation, storage, and use makes its mass production/application possible.
