锂硫聚合物二次电池关键材料研究进展

Recent Progress in the Key Materials for Li/S Polymer Secondary Batteries

报告了在复合型纳米硫正极材料、纳米储锂合金负极材料和用原位合成工艺掺入纳米二氧化硅的凝胶型聚合物电解质的研制方面所取得的进展;所研制的复合型纳米硫正极材料与凝胶电解质及锂金属负极配合制成扣式实验电池进行测试,容量已达到700 mAh/g,发现该材料放电电压是现有锂钴氧材料放电电压的一半,双电池串联可以与现有锂钴氧材料电池互换;采用微乳液新工艺合成的Cu-Sn纳米合金材料,以石墨与金属锡复合的材料,以及以金属氧化物作为原料,采用乳液法制备碳微球镶嵌金属锡的球形复合材料等高容量负极材料取得了较大的进展,并尝试了利用锂钴氮化物补偿负极的首次不可逆容量损失;合成的Poly(AN-MMA)共聚物和Poly(AN-BuA)共聚物制备的凝胶电解质均取得进展,可望制作出以纳米锂合金为负极、固态聚合物为电解质和纳米硫复合材料为正极的高比能量电池。

A nano-scale sulfur polymer composite cathode material has been developed for Li/S polymer secondary batteries, and its cycle capacity is over 700 mAh/g when the lithium metal is used as the anode. Its discharge voltage is the half of that of LiCoO2, showing the exchangeability between the nano sulfur battery and LiCoO2 battery. Graphite/Sulfur cell works well. Nano-scale Cu/Sn alloy powder has been synthesized by a novel micro-emulsion process. Its cycling capacity is over 300 mAh/g. Both Sn/C composite prepared by ball milling and Sn/C microspheric composite prepared by carbothermal reduction show good electrochemical performance. Lithium compensation of anode materials by Li2.6Co0.4N for the initial irreversible capacity paves the way to prepare large capacity anode materials. The successful preparation of Poly（AN - MMA） and Poly （AN - BuA） copolymers shows that the cost of gel electrolyte can be reduced. The advanced Li/S polymer secondary batteries will be developed in the near future.