碳材披覆於矽／石墨／氮化鋁複合物之鋰離子電池負極材料性能研究

Carbon-Coated Si/Graphite/AlN Composites as Anode Materials for Lithium Ion Batteries

本研究主要是將矽、石墨和氮化鋁三種材料，依不同的混合比例與處理形成複合材料，作為鋰離子電池負極材料。當矽／石墨／氮化鋁複合材料分別以不同的重量比例，再披覆40 wt.%的咈喃樹脂，經8小時研磨後，由充放電測試結果發現，利用緩衝效應將氮化鋁視為一種非活性的緩衝材，與矽混合後能抑制矽於充放電時的體積膨脹問題，有效改善電容量的循環穩定性，並降低第一次不可逆性至10%，且經過5 次充放電循環測試後電容量可維持在700mAh/g左右，其電化學性能顯示有較佳的電容量和穩定的循環壽命。因為氮化鋁的加入與研磨處理，有助於矽的第一次不可逆電容量降低；另將矽複合材料披覆咈喃樹脂處理後，其電容量的衰退較為穩定，且循環穩定性也有所提升。

Silicon/graphite/aluminum nitride (AlN) composites with differentweight ratios were mixed as precursors for anode materials of Li-ionbatteries. The silicon/graphite/AlN composites with different proportionsof weight separately and coating containing 40 wt.% furan resin aftermilling for 8 hours, are measured with charge and discharge tests. Theinactive AlN working as a buffer matrix successfully prevents silicon largevolume change during charge and discharge electrochemical test. Thecomposites show excellent cycling performance with a reasonable value ofthe first irreversible capacity to 10%. The capacity is retained about 700mAh/g after 5 cycles. The first irreversibility will obviously be reduced.The capacity decade of carbon-coated silicon composites with furan resinwill be comparatively steady and the circulation stability will be alsoimproved.