不同粘结剂对硅/多孔石墨烯复合负极性能的影响  

Effects of different binders on the properties of porous graphene/silicon composite anode

作　　者：李藏龙 李翔晟[1] 梅琳 曾军 张心成 Li Canglong;Li Xiangsheng;Mei Lin;Zeng Jun;Zhang Xincheng(College of Mechanical and Electrical Engineering,Central South University of Forestry and Technology,Changsha 410004;State Key Laboratory of Powder Metallurgy,Central South University,Changsha,410083)

机构地区：[1]中南林业科技大学机电工程学院,长沙410004 [2]中南大学粉末冶金国家重点实验室,长沙410083

出　　处：《化工新型材料》2023年第8期95-99,共5页New Chemical Materials

基　　金：湖南省自然科学基金省市联合项目(14JJ5014);中南林业科技大学研究生科技创新基金(CX202102039)。

摘　　要：锂离子电池硅负极材料具有比容量高、电压平台低等优势,粘结剂的结构和类型对硅负极的电化学储能性能具有较大影响。选取不同结构的粘结剂(聚丙烯酸、聚偏氟乙烯、羧甲基纤维素钠、聚丙烯酰胺)分别与硅/多孔石墨烯复合材料混合制浆涂布,组装成锂离子半电池。在相同的电流密度下,研究不同粘结剂对硅/多孔石墨烯复合负极材料的电化学储能影响。测试结果表明,以聚丙烯酰胺作为粘结剂的硅/多孔石墨烯复合负极材料,首次放电循环比容量为2623mAh/g,初始库伦效率为84.4%,循环100次后比容量仍保持为1462mAh/g。相较于其他粘结剂,聚丙烯酰胺的三维交联网络结构具有较强的机械强度,可以通过其共价网络结构来缓解Si负极体积膨胀造成的容量衰减现象。本研究可为锂离子电池硅复合负极材料粘结剂的选择和设计提供依据。Silicon anode materials for lithium-ion batteries have the advantages of high specific capacity and low voltage plateau,and the structure and type of binders have a significant impact on the electrochemical energy storage performance of silicon anodes.In this paper,polyacrylic acid(PAA),polyvinylidene fluoride(PVDF),sodium carboxymethyl cellulose(CMC),and polyacrylamide(PAM)were selected and mixed with Si/pG composite,respectively,to prepare slurry coating for assembling lithium-ion half-cells.The effects of different binders on the electrochemical energy storage of Si/pG anode were studied under the same current density.The test results showed that for Si/pG-PAM anode,the specific capacity of the first discharge cycle was 2623mAh·g-1 with an initial Coulomb efficiency of 84.4%,and the specific capacity remained at 1462mAh·g-1 after 100 cycles.Compared with other binders,the 3D cross-linked network of PAM had strong mechanical strength,and its covalent network structure could alleviate the capacity decay caused by the volume expansion of the silicon anode.This study provided research bases for the design and selection of binder for Si composite anode for lithium-ion batteries.

关 键 词：锂离子电池 粘结剂 硅负极材料 复合材料 电化学性能 

分 类 号：TB332[一般工业技术—材料科学与工程]