锂离子电池铜集流体表面集电结构加工及性能研究

摘要

The conductivity of copper current col ector has a greater impact on the capacity and cycling performance of lithium￣ion batteries. In this study, copper sheets with three kinds of micro￣columnar surface structures which are machined by using the WEDM ( Wire electrical discharge machining) are coated with slurry of five different viscosities and then dried with five different temperatures respectively. Consequently,the plates are assembled to the test body,whose resistance is detected with the test cir￣cuit. The results reveal that when the composition and ingredient of slurry are fixed, the conductive property of the copper current col ector with micro￣columnar surface structures is improved by 8%,compared with those with smooth surface. And the conductivi￣ty of the negative electrode plate is the best when the viscosity of the slurry is at 2 900 mpa�s or 3 500 mpa�s, and the drying temperature is at 70 ℃.%铜集流体的导电性能对锂离子电池的容量和循环性能有着较大的影响。采用电火花线切割加工出三种微柱状结构表面的铜片，并在铜片表面涂布五组不同黏度的浆料制作成极板，再用五组不同的烘干温度烘干，烘干后将极板组装成测试体，通过测试电路测试其电阻。研究发现，在浆料成分和配比固定不变的情况下，具有微柱状表面结构的铜集流体的导电性能比光滑表面结构的铜集流体的导电性能提高了约8％，而浆料黏度为2900 MPa�s、3500 MPa�s，干燥温度为70℃制得的负极板的导电性能最好。