This technology incorporates both lithium silicate and a transition metal-silicon alloy into the microstructure of a silicon-based anode active material to structurally buffer silicon volume expansion during charge/discharge cycles while ensuring ionic conductivity and mechanical stability.
Silicon undergoes volume changes of up to 300% during lithium insertion and extraction, leading to cracking on the surface of the active material and electrical isolation. This results in low capacity retention and poor thermal stability during high-temperature storage.
This technology involves ball-milling silicon monoxide with a transition metal precursor followed by heat treatment to create a transition metal-silicon alloy. This is then mixed with a lithium precursor and heat-treated again to produce a composite anode active material with the alloy uniformly dispersed within a lithium silicate structure. The alloy content is controlled at 1.6–10 wt%, the specific surface area at 4.85–6.69 m²/g, and the porosity at 0.0302–0.0330 cm³/g. Applicable to high-capacity anodes for long-range EVs, compact high-density cells for smartphones, and industrial batteries for high-temperature environments, it allows for higher silicon content while reducing capacity loss caused by particle cracking.
US2025-0087671A1, WO2023-234729A1
