电镀复合铜箔添加剂的研究

A composite additive for electroplating composite copper foil

[目的]复合铜箔作为锂电负极集流体的新兴关键基础材料,其制备过程中水电镀工艺的镀铜添加剂成为研究重点。[方法]先通过霍尔槽试验和电化学分析筛选硫酸盐体系电镀铜的促进剂、抑制剂和整平剂,然后模拟现场环境进行电镀实验以获得较优的添加剂配方。[结果]较佳的添加剂配方为:聚二硫二丙烷磺酸钠(SPS)2 g/L,改性聚乙二醇100 g/L,整平剂C(硫脲基咪唑啉季铵盐)1 g/L。采用该复合添加剂时,可在超薄有机高分子薄膜两面镀上厚度1~2μm的铜。所得复合铜箔的总厚度约为6μm,具有高抗拉强度(292.39~297.98 MPa)和高断裂伸长率(21.34%~22.68%),外观无异常且不翘曲。[结论]该复合添加剂有望用于制备高抗高延的复合铜箔,具有很好的工业化应用前景。

[Introduction]Composite copper foil is a novel key material for current collector of negative electrode of lithium-based battery,and the additives used in copper electroplating for its preparation has become the focus of research.[Method]The accelerator,inhibitor,and leveling agent of sulfate-based copper electroplating were selected by Hull cell test and electrochemical analysis,and then electroplating tests were conducted under the simulated on-site environment to determine the most suitable combination of the additives.[Result]The optimized additive composition was as follows:sodium 3,3′-dithiodipropane sulfonate(SPS)2 mg/L,modified polyethylene glycol 100 mg/L,and leveling agent C(a kind of thioureido-imidazoline quaternary ammonium salt)1 mg/L.A copper coating with a thickness of 1-2μm could be obtained on both sides of an ultrathin polymer film by electroplating with the given composite additive.The obtained composite foil was normal in appearance and warp-free with a total thickness of 6μm,and had high tensile strength(292.39-297.98 MPa)and elongation at break(21.34%to 22.68%).[Conclusion]The composite additive given above is expected to be applied to the preparation of composite copper foil with high tensile strength and high elongation,and has a good industrial application prospect.