3results about How to "Reduced electrochemical performance" patented technology

The invention discloses a sodium ion battery single crystal positive electrode material and a preparation method and application thereof, and the material realizes high working voltage, excellent cycling stability and rate capability by accurately controlling chemical composition and microstructure. According to the preparation method, the problem that part of doped metal ions cannot be synthesized into the precursor through a coprecipitation method or synthesized into the precursor in a high proportion can be solved, the microstructure and element distribution uniformity of the material can be effectively controlled, and the performance is more excellent than that of a conventional multi-component oxide mechanical solid-phase synthesis method; the addition of the molten salt can optimize the single crystal morphology and reduce the sintering temperature, the doping of the M element can stabilize the structure and improve the air stability and the cycling stability under high voltage, and the coating of the oxygen-containing compound can reduce the side reaction of the positive electrode material and an electrolyte interface and the electrochemical performance under high voltage. The first-circle discharge specific capacity is 173.34 mAh / g, and the capacity retention ratio is still 91.5% after 100 times of cyclic charge and discharge.

The application provides a porous silicon substrate and a preparation method thereof, a porous silicon negative electrode material, a negative electrode sheet and a battery. The pores of the porous silicon substrate include mesopores and macropores. In the porous silicon substrate, the sum of the volumes of the mesopores is A, the sum of the volumes of the macropores is B, and the sum of the volumes of the pores is C. A / C is 60% to 72%, and B / C is 28% to 40%. When the porous silicon substrate is applied to a negative electrode material, the porous silicon substrate has a low volume expansion rate, good structural stability and a high specific capacity.

The present application provides a silicon-based composite negative electrode material, the silicon-based composite negative electrode material comprising a silicon-based material core, and an antiperovskite solid electrolyte layer and a sulfur-based solid electrolyte layer sequentially covering the silicon-based material core, the antiperovskite solid electrolyte layer comprising Li 3‑t OH t A, wherein A is at least one of Cl, Br and I, and 0≤t≤2. The silicon-based composite negative electrode material has low impedance, high ion conductivity and outstanding electrochemical performance. The application also provides a preparation method of the silicon-based composite negative electrode material and an all-solid-state lithium battery.