新能源行业的繁荣，极大程度上促进了电解铜箔行业的发展。电解铜箔作为负极集流体，是锂离子电池不可或缺的原材料。锂离子电池要求电解铜箔具有晶粒细小、表面糙度低、超薄、硬度高等特点，确保电池负极活性物质与集流体的紧密接触，保持电池容量，提高电池安全性。因此，对高强超薄电解铜箔的制备及其性能的研究具有重要意义。电解液是电解铜箔制备的基础，沉积工艺和有机添加剂则是调控电解液性质的重要因素，显著影响铜箔的微观组织与性能。本文主要以电解铜箔生产普遍采用的硫酸铜酸性溶液为基础电解液，探究稳定、高效且适合的脉冲电沉积工艺参数，明确四种有机添加剂以及其对应的复合添加剂在铜箔电沉积过程中的添加量及作用机制，以期优化铜箔生产工艺，提升铜箔品质。

本课题主要研究内容及结论如下：

(1) 通过单因素实验，选用稳定的基础电解液(Cu²⁺浓度：40 g/L、浓H₂SO₄浓度：110 g/L)，研究脉冲电沉积时间、温度和电压对铜箔厚度、维氏(Vickers)显微硬度、表面粗糙度以及组织形貌的影响。结果表明：在电镀时间3 min，电解液温度50℃，脉冲电压2.5 V时，铜箔表面光亮平整，颗粒尺寸较小。此时，铜箔厚度达到了6 μm以下，显微硬度最高，表面粗糙度较小，分别为5.89 μm、251.66 HV0.05和2.199 μm。基础电解液制备铜箔的铜晶粒的平均尺寸为116.7 nm，铜箔表现为(111)晶面择优取向。

(2) 研究了聚二硫二丙烷磺酸钠(SPS)、羟乙基纤维素(HEC)、明胶和胶原蛋白四种有机添加剂对电解铜箔组织及性能的影响，并探究其对铜箔电沉积作用机制。结果表明：SPS、明胶和胶原蛋白均具有晶粒细化和整平的作用。其中，胶原蛋白具有更强的细化晶粒的作用，添加浓度为0.08 g/L时铜箔的表面平均颗粒尺寸和晶粒大小较基础电解液分别下降83.8%和45.5%。此时，铜箔的厚度、Vickers显微硬度和表面粗糙度均达到最优值，分别为5.12 μm、279.63 HV_0.05和1.885 μm。HEC在此基础电解液体系下不具有晶粒细化的作用，但在其浓度为0.12 g/L时，铜箔表面粗糙度达到最低为1.828 μm。研究发现，电解铜箔具有高显微硬度是晶粒细化及(220)晶面择优取向综合作用的结果。初步推断SPS抑制铜离子沉积机理是SPS与Cu⁺产生的络合物发生了先吸附后脱附，从而增大了阴极极化，使得晶粒细小。

(3) 研究了SPS、HEC和胶原蛋白形成的双组份和三组份复合添加剂体系对铜箔微观组织及性能的影响，分析了双组份复合添加剂对铜离子沉积的电化学行为。结果表明：SPS与胶原蛋白形成的体系(SC)优于SPS与HEC形成的体系(SH)，SH双组分复合添加剂，具有去极化作用，且阴极电沉积铜所需的势垒较小，对铜离子的沉积具有促进作用，微观组织不均匀，颗粒度尺寸较大。说明SPS与HEC两种添加剂之间存在拮抗作用，HEC的添加使SPS晶粒细化的作用减弱。正交实验研究SPS、HEC和胶原蛋白形成的三组份复合添加剂(SHC)。研究发现，SPS添加量对于铜箔显微硬度的影响最大，铜箔表面粗糙度的大小主要由HEC浓度所控制。SPS、HEC和胶原蛋白形成的双组份(SH、SC)、三组份复合添加剂(SHC)对于晶粒晶面的生长没有形成新的择优取向，(111)晶面的织构系数TC(111)仍为最大，依旧为(111)晶面择优取向。

The prosperity of new energy industry has greatly promoted the development of electrolytic copper foil industry. As a negative collector, electrolytic copper foil is an indispensable raw material for lithium-ion batteries. Lithium-ion batteries require electrolytic copper foil to have the characteristics of fine grain, low surface roughness, ultra-thin and high hardness, so as to ensure the close contact between the negative active material of the battery and the collector, maintaining the battery capacity and improving the safety of the battery. Therefore, it is of great significance to study the preparation and properties of high-strength ultra-thin electrolytic copper foil. Electrolyte is the basis for the preparation of electrolytic copper foil. Deposition process and organic additives are important factors to regulate the properties of electrolyte, which significantly affect the microstructure and properties of copper foil. In this paper, the basic electrolyte is acidic copper sulfate solution, which is widely employed in the production of electrolytic copper foil. The stable, efficient and suitable process parameters of pulse electrodeposition were explored. The addition amount and action mechanism of four organic additives and their corresponding composite additives in the process of copper foil electrodeposition were clarified, in order to optimize the copper foil production process and improve the quality of copper foil.

The main research contents and conclusions are as follows:

(1) Through single factor experiment, stable basic electrolyte (Cu²⁺: 40 g/L、concentrated H₂SO₄: 110 g/L) was selected to study the effects of pulse electrodeposition time, temperature and voltage on the thickness, Vickers microhardness, surface roughness and microstructure morphologies of copper foil. Results revealed that when the electroplating time was 3 min, electrolyte temperature was 50℃ and pulse voltage was 2.5 V, the surface of copper foil was bright and flat, and the particle size was small. At present, the thickness of copper foil was less than 6 μm, the microhardness was the highest, and the surface roughness was small, which were 5.89 μm, 251.66 HV_0.05 and 2.199 μm, respectively. The average grain size of copper foil prepared by basic electrolyte was 116.7 nm, and the copper foil showed the preferred orientation of (111) crystal plane.

(2) The effects of four organic additives such as SPS, HEC, gelatin and collagen on the microstructure and properties of electrolytic copper foil were studied, and the mechanism on copper foil electrodeposition was explored. The results showed that SPS, gelatin and collagen had the effect of grain refinement and leveling. Among them, collagen had a stronger effect on grain refinement. and the average surface particle size and grain size of copper foil with the addition concentration of 0.08 g/L were 83.8% and 45.5% lower than that of the basic electrolyte, respectively. Meanwhile, the thickness of copper foil, Vickers microhardness and surface roughness reached the optimal values, which were 5.12 μm、279.63 HV_0.05 and 1.885 μm. The HEC electrolytic liquid system had no grain refining ability, but the lowest surface roughness of copper foil was 1.828 μm at the concentration of 0.12 g/L. The study found that the high microhardness of electrolytic copper foil was the result of the combined effect of grain refinement and preferred orientation of (220) crystal surface. It is preliminarily concluded that the mechanism of SPS inhibiting copper ion deposition was that the complex produced by SPS and Cu⁺ was adsorbed and desorbed, which increased the cathodic polarization and made the grains smaller.

(3) The effects of two-component and three-component composite additives formed by SPS, HEC and collagen on the microstructure and properties of copper foil were investigated, and the electrochemical behavior of two-component composite additives on copper ion deposition was analyzed. The results demonstrated that the system of SPS and collagen formation (SC) was superior to the system of SPS and HEC formation (SH). SH had the effect of depolarization, and the cathode electrodeposition of copper required a smaller barrier, which can promote the deposition of copper ions. Therefore, the microstructure was not uniform and the particle size was large. This indicated that there was antagonism between SPS and HEC, and the addition of HEC weakened the effect of SPS grain refinement. Three component composite additive (SHC) for SPS, HEC and collagen formation was studied by orthogonal experiment. It was found that the addition of SPS had the greatest influence on the microhardness of copper foil, and the surface roughness of copper foil was mainly controlled by concentration of HEC. The two-component (SH, SC) and three-component composite additive (SHC) formed by SPS, HEC and collagen did not form a new preferred orientation for the growth of grain plane, and TC₍₁₁₁₎ was still the largest and the preferred orientation of (111) crystal plane as before.

[1] 余威懿. 锂离子电池用电解铜箔的制备工艺与性能研究[D]. 哈尔滨: 哈尔滨工业大学, 2019.

[2] 周启伦, 林敬根. 电解厚铜箔性能及其技术新发展[C]//第十八届中国覆铜板技术·市场研讨会论文集. 东莞: 覆铜板资讯期刊社, 2017: 269-279.

[3] Pena E D, Roy S. Electrodeposited copper using direct and pulse currents from electrolytes containing low concentration of additives[J]. Surface & Coatings Technology, 2018, 339: 101-110.

[4] 朱凤鹃, 李宁, 黎德育. 印制电路板电镀铜添加剂的研究进展[J]. 电镀与精饰, 2008, 30(8): 16-20.

[5] Suzuki A, Shinozaki J. Copper foil smooth on both sides for lithium-ion battery[J]. Springer New York, 2014, 171: 229-265.

[6] 樊小伟. 超薄电解铜箔组织结构与力学性能调控及其表面处理技术研究[D]. 赣州: 江西理工大学, 2021.

[7] Lin C C, Yen C H, Lin S C, et al. Interactive effects of additives and electrolyte flow rate on the microstructure of electrodeposited copper foils[J]. Journal of the Electrochemical Society, 2017, 164(13): D810-D817.

[8] 张彪. 高密度互连印制电路板用超低轮廓电解铜箔的研究[D]. 武汉: 华中科技大学, 2011.

[9] 王征. 电解铜箔表面电沉积镀层及沉积模型研究[D]. 哈尔滨: 哈尔滨工业大学, 2007.

[10] Yin X Q, Peng L J, Kayani S, et al. Mechanical properties and microstructure of rolled and electrodeposited thin copper foil[J]. Rare Metals, 2016, 35(12): 909-914.

[11] 吴继烈. 电解铜箔市场走势[J]. 有色金属工业, 2003(1): 55-56.

[12] 眭乐萍, 席晓丽. 锂离子电池用电解铜箔领域专利技术综述[J]. 科技创新与应用, 2018(23): 21-22.

[13] 余三宝. 电解铜箔常见问题及解决方法[J]. 世界有色金属, 2016(5): 19-20.

[14] 何铁帅, 樊斌锋, 何晨曦. 6 μm高抗拉强度锂电池铜箔的工艺研究[J]. 有色金属加工, 2019, 48(3): 33-36.

[15] 易光斌. 电解铜箔组织性能及其翘曲产生机理研究[D]. 南昌: 南昌大学, 2014.

[16] 袁孚胜. 中国电解铜箔市场现状及发展趋势[J]. 有色冶金设计与研究, 2019, 40(5): 4.

[17] 陈伟豪. 高稳定性金属锂负极三维集流体研究[D]. 成都: 电子科技大学, 2021.

[18] 王妮. 电化学方法构建多孔金属薄膜及性能研究[D]. 成都: 电子科技大学, 2012.

[19] 邓庚凤, 何桂荣, 黄崛起, 等. 超薄铜箔的制备工艺研究[J]. 有色金属(冶炼部分), 2014(2): 50-53.

[20] 徐宏刚, 王碧侠, 王子钰, 等. 氢气泡模板法电沉积制备三维多孔铜的工艺参数研究[J]. 矿冶工程, 2020, 40(5): 115-119.

[21] 孙云飞, 王学江, 徐策, 等. 超声波对电沉积多孔铜箔的影响[J]. 贵州师范大学学报(自然科学版), 2019, 37(1): 26-29.

[22] Sun Y, Peng L, Huang G, et al. Effect of Mg on the stress relaxation resistance of Cu-Cr alloys[J]. Materials Science and Engineering A, 2021, 799: 140144.

[23] Liu F, Li J, Peng L, et al. Simultaneously enhanced hardness and electrical conductivity in a Cu-Ni-Si alloy by addition of Cobalt[J]. Journal of Alloys and Compounds, 2021, 862: 158667.

[24] 王文静. 铜箔表面刷镀—去合金化处理工艺基础及机理[D]. 北京: 北京科技大学, 2017.

[25] Kalantary M R, Gabe D R. Physical properties of pulsed current copper electrodeposits[J]. Journal of Materials Science, 1995, 30(18): 4515-4522.

[26] Chiang Y Y, Wan W. Research on applying direct plating to additive process for printed circuit board[J]. Journal of Electronic Materials, 2000, 29(8): 1001-1006.

[27] 梁培, 张晓波, 王珂. 印刷电路板双向脉冲镀铜可编程开关电源研制[J]. 电镀与精饰, 2019, 41(3): 31-35.

[28] 雷光发, 江泽军, 董发君. 谈PCB垂直移动连续电镀线采用脉冲整流器与直流整流器的效果比较[J]. 印制电路信息, 2020, 28(7): 43-48.

[29] Lee Y K, O'Keefe T J. Evaluating and monitoring nucleation and growth in copper foil[J]. JOM: the Journal of the Minerals, Metals & Materials Society, 2002, 54(4): 37-41.

[30] 胡善勇, 王文明. 简析电子线路板微沟槽脉冲镀铜填充工艺[J]. 电子制作, 2018(14): 66-67.

[31] Wa Ng W, Liu X. Influences of brush plating solutions composition and technological parameters on the quality of rolled copper foil surface coatings[J]. Journal of Materials Research, 2015, 30(24): 3766-3775.

[32] 赵玲艳. 电解铜箔工艺条件及其添加剂的实验研究[D]. 赣州: 江西理工大学, 2008.

[33] 陈程, 李敏, 李立清, 等. 高性能电解铜箔表面处理工艺研究进展[J]. 广州化工, 2016, 44(2): 10-13.

[34] Mallik A. An analysis on the effect of temperature on electrocrystallization mechanism during deposition of Cu thin films[J]. Transactions of the Indian Institute of Metals, 2013, 66(1): 79-85.

[35] 金荣涛. 电解铜箔生产[M]. 长沙: 中南大学出版社, 2009: 69.

[36] 冯绍彬, 苏畅. 酸性镀铜工艺硫酸过量引起的故障分析[J]. 电镀与涂饰, 2011, 30(4): 13-14.

[37] 孙玉梅. 退火工艺和粗化处理对压延银铜箔组织及性能的影响[D]. 淄博: 山东理工大学, 2021.

[38] Lai Z Q, Wang C, Huang Y Z, et al. Temperature-dependent inhibition of PEG in acid copper plating: theoretical analysis and experiment evidence[J]. Materials Today Communications, 2020, 24: 100973.

[39] 蔡芬敏. 电沉积参数对电解铜箔组织性能的影响[D]. 南昌: 南昌大学, 2011.

[40] 唐明星. 印制电路板酸性电镀铜电镀添加剂的应用及其机理研究[D]. 重庆: 重庆大学, 2018.

[41] 王艳. 铜箔表面稀土添加剂处理工艺及耐蚀性研究[D]. 赣州: 江西理工大学, 2014.

[42] 李立清, 王义, 安文娟. 酸性硫酸盐镀铜添加剂研究[J]. 电镀与精饰, 2016, 38(11): 20-23.

[43] Wang T, Zhao R, Zhan K, et al. Preparation of electro-reduced graphene oxide/copper composite foils with simultaneously enhanced thermal and mechanical properties by DC electro-deposition method[J]. Materials Science and Engineering A, 2020, 805: 140574.

[44] 孙玥, 刘玲玲, 李鑫泉, 等. 添加剂对电解铜箔作用机理及作用效果的研究进展[J]. 化工进展, 2021, 40(11): 1-19.

[45] Liu L L, Bu Y Q, Sun Y, et al. Trace bis-(3-sulfopropyl)-disulfide enhanced electrodeposited copper foils[J]. Journal of Materials Science & Technology, 2021, 74(15): 237-245.

[46] 王庆福, 李应恩, 樊斌锋. 锂电池用6 μm电解铜箔添加剂的研究[J]. 电镀与环保, 2020, 40(3): 23-26.

[47] 凌小莲. 电子线路板微沟槽脉冲镀铜填充工艺的研究[J]. 电镀与环保, 2014, 34(2): 19-21.

[48] 程曦. 电解工艺对电解铜箔组织与性能影响的研究[D]. 北京: 北京有色金属研究总院, 2019.

[49] 陆冰沪, 师慧娟, 李大双, 等. 概述氯离子对电解铜箔的影响[J]. 电镀与涂饰, 2019, 38(24): 1324-1328.

[50] 姚国欢. 添加剂对电解铜箔组织性能的影响及优化[J]. 化工管理, 2020(33): 176-177.

[51] Tadesse B, Horne M, Addai-Mensah J. The effect of thiourea, L(−) cysteine and glycine additives on the mechanisms and kinetics of copper electrodeposition[J]. Journal of Applied Electrochemistry, 2013, 43: 1185-1195.

[52] 辜敏, 李强, 鲜晓红, 等. PEG-Cl-添加剂存在下的铜电结晶过程研究[J]. 化学学报, 2007, 65(10): 881-886.

[53] 李强. 添加剂PEG、Cl-、SPS作用下的铜电结晶过程研究[D]. 重庆: 重庆大学, 2007.

[54] 黄金豆. Cl-DPS-NP-n及Cl-BSP-AEO-n系列高性能电解铜箔添加剂的研究[D]. 广州: 华南理工大学, 2016.

[55] Tan M, Guymon C, Wheeler D R, et al. The Role of SPS, MPSA, and Chloride in additive systems for copper electrodeposition[J]. Journal of the Electrochemical Society, 2007, 154(2): D78-D81.

[56] 刘耀, 陆冰沪, 樊小伟, 等. 钨酸钠复合添加剂深镀粗化电解铜箔表面处理工艺研究[J]. 表面技术, 2020, 49(11): 168-176.

[57] 方亚超, 潘明熙, 黄惠, 等. 铜电解沉积过程中添加剂的影响研究现状及展望[J]. 矿冶, 2021, 30(5): 61-69.

[58] Jo Y E, Yu D Y, Cho S K. Revealing the inhibition effect of quaternary ammonium cations on Cu electrodeposition[J]. Journal of Applied Electrochemistry, 2019, 50(2): 245-253.

[59] 丁辛城. 电解铜箔添加剂的研究及电解液中各组份浓度的检测[D]. 广州: 华南理工大学, 2015.

[60] 黄家龙. 电解铜箔添加剂及其作用下铜快速电结晶过程的研究[D]. 广州: 华南理工大学, 2013.

[61] 黄隆. 印刷模板法制备多孔铜箔及其锂离子电池集流体应用研究[D]. 哈尔滨: 哈尔滨工业大学, 2019.

[62] 姚可夫, 翟桂东. 纳米晶材料的力学性能与研究进展[J]. 机械工程材料, 2004, 28(1): 26-28+37.

[63] Apakashev R A, Khazin M L, Valiev N G. Effect of Temperature on the Structure and Properties of Fine-Grain Copper Foil[J]. Metal Science and Heat Treatment, 2020, 62(12): 42-46.

[64] Hakamada M, Nakamoto Y, Matsumoto H, et al. Relationship between hardness and grain size in electrodeposited copper films[J]. Materials Science & Engineering A, 2007, 457(1-2): 120-126.

[65] 胡旭日, 王海振, 徐策. 粗化工艺对电解铜箔表面铜粉的影响[J]. 电镀与涂饰, 2017, 36(1): 31-35.

[66] Hong B, Jiang C H, Wang X J. XRD characterization of texture and internal stress in electrodeposited copper films on Al substrates[J]. Powder Diffraction, 2007, 22(4): 324-327.

[67] Chen C L, Tzou M J. Electrolytic copper foil, method for producing the same, and lithium ion secondary battery: US20200350620A1[P]. 2020-11-05.

[68] Zhang Y, Hang T, Dong M, et al. Effects of 2-mercaptopyridine and Janus Green B as levelers on electrical resistance of electrodeposited copper thin film for interconnects[J]. Thin Solid Films, 2019, 677: 39-44.

[69] 朱若林, 宋言, 代泽宇, 等. 骨胶和聚二硫二丙烷磺酸钠对厚电解铜箔性能的影响[J]. 电镀与涂饰, 2021, 40(13): 1027-1030.

[70] Tan M, Harb J N. Additive behavior during copper electrodeposition in acidic solution containing Cl-, PEG, and SPS[J]. Journal of the Electrochemical Society, 2003, 150(6): 420-425.

[71] Huynh T M T, Weiss F, Hai N T M, et al. On the role of halides and thiols in additive-assisted copper electroplating[J]. Electrochimica Acta, 2013, 89: 537-548.

[72] 徐建平. 电解铜箔添加剂研究进展[J]. 世界有色金属, 2018(15): 162-163.

[73] 黄令, 辜敏, 杨防阻, 等. 聚二硫二丙烷磺酸钠对铜电沉积初期行为的影响研究[C]//京津沪渝四直辖市表面工程技术交流会. 重庆: 重庆市电镀行业协会, 2002: 47-49.

[74] 李权. 聚二硫二丙烷磺酸钠对铜电沉积过程的表面作用机理研究[J]. 四川师范大学学报(自然科学版), 1999, 22(1): 73-75.

[75] Hebert K R. Analysis of current-potential hysteresis during electrodeposition of copper with additives[J]. Journal of the Electrochemical Society, 2001, 148(11): C726-C732.

[76] Kim T Y, Sung M, Yoon Y, et al. Observation of bis-(3-sulfopropyl) disulfide (SPS) breakdown at the cu cathode and insoluble anode under open-circuit, unpowered closed-circuit, and electrolysis conditions[J]. Journal of the Electrochemical Society, 2019, 166(8): G61-G66.

[77] Yu W, Lin C, Li Q, et al. A novel strategy to electrodeposit high-quality copper foils using composite additive and pulse superimposed on direct current[J]. Journal of Applied Electrochemistry, 2021, 51(3): 489-501.

[78] Koura N, Ejiri Y, Mamiya M, et al. Effects of gelatine and chloride ion on copper electrodeposition II[J]. Journal of the Surface Finishing Society of Japan, 2000, 51(9): 938-944.

[79] Wang J L, Fu M W, Shi S Q. Influences of size effect and stress condition on ductile fracture behavior in micro-scaled plastic deformation[J]. Materials & Design, 2017, 131: 69-80.

[80] Gómez-Guillén M C, Giménez B, López-Caballero M E, et al. Functional and bioactive properties of collagen and gelatin from alternative sources: A review[J]. Food Hydrocolloids, 2011, 25(8): 1813-1827.

[81] Yi G, Cai F, Peng W, et al. Experimental analysis of pinholes on electrolytic copper foil[J]. Engineering Failure Analysis, 2012, 23: 76-81.

[82] Lai Z, Wang S, Wang C, et al. A comparison of typical additives for copper electroplating based on theoretical computation[J]. Computational Materials Science, 2018, 147: 95-102.

[83] 张世超, 蒋涛, 白致铭. 电解铜箔材料中晶面择优取向[J]. 北京航空航天大学学报, 2004(10): 1008-1012.

[84] Zhang Y G, Sun W C, Dong Y R, et al. Electrodeposition and microstructure of Ni and B co-doped diamond-like carbon (Ni/B-DLC) films[J]. Surface & Coatings Technology, 2021, 405: 126713.

[85] 袁智斌. 锂电池用8微米超薄双面光电解铜箔工艺研究[D]. 南昌: 南昌大学, 2014.

[86] Woo T G, Park I S, Seol K W. Effect of additives on the elongation and surface properties of copper foils[J]. Electronic Materials Letters, 2013, 9(3): 341-345.