蚕丝/聚氧化乙烯复合固态聚合物电解质

Silk/polyoxyethylene composite solid polymer electrolyte

摘要:

以天然蚕丝为骨架支撑材料，将聚氧化乙烯（PEO）和锂盐溶液浇铸在蚕丝上干燥成膜，制备得到蚕丝/聚氧化乙烯复合固态聚合物电解质（Silk-PEO-SPE）。通过傅里叶变换红外光谱（FT-IR）、电子拉力机、同步热分析仪、电化学窗口测试、电导率测试对固态聚合物电解质进行结构和性能表征，并以磷酸铁锂为正极，金属锂为负极组装全固态电池，测试了电池的充放电性能。结果表明：与传统PEO固态聚合物电解质相比，复合固态聚合物具有较好的机械强度（达到10MPa）和优异的电化学窗口（达到4.6V），以该电解质组装的全固态锂电池在60℃、1C电流密度下放电比容量达到113mAh/g，循环100次容量保持率达到97%，显示出较优异的循环稳定性。

Abstract:

Silk/polyethylene oxide composite solid polymer electrolyte was prepared by casting polyethylene oxide (PEO) and lithium salt solution on silk and drying it into a film with natural silk as the skeleton supporting material. The structure and properties of the solid polymer electrolyte were characterized by FT-IR, tensile tester, synchronous thermal analyzer, electrochemical window test, conductivity test, etc. The battery was assembled with lithium iron phosphate as the positive electrode and lithium metal as the negative electrode to test the charging and discharging performance. The results show that the composite solid polymer has better mechanical strength (up to 10 MPa) and an excellent electrochemical window (up to 4.6 V) compared with the conventional PEO solid polymer electrolyte. The specific capacity of all-solid-state lithium batteries assembled with the electrolyte reaches 113 mAh/g at 60℃and 1C current density, and the capacity retention rate reaches 97% after 100 cycles, showing excellent cycle stability.