以羧甲基纤维素钠(CMC)/丁苯橡胶(SBR)、聚丙烯酸(PAA)、丙烯酸衍生物多元共聚物(LA136D)为粘结剂,多孔硅/石墨复合材料作为负极分别组装了锂离子半电池,研究了不同结构粘结剂对复合材料电化学性能的影响。结果表明,以PAA作为粘结剂的复合材料首次放电比容量为564.98mAh/g,初始库伦效率为84.6%,经过120次循环后放电比容量为437.70mAh/g,相较于第二圈(放电比容量507.97mAh/g)容量保持率为86.2%。相比其他粘结剂,PAA的三维交联网络结构赋予复合材料材料更强的机械强度和结构稳定性,能够有效缓解硅在充放电过程中因体积膨胀引起的结构破坏。
Sodium carboxymethyl cellulose (CMC)/styrene-butadiene rubber (SBR),polyacrylic acid (PAA) and an acrylic-derived multi-component copolymer (LA136D) were used as binders to assemble lithium-ion half-cells with porous silicon/graphite composites as the anode material.The effects of different binder structures on the electrochemical performance of the composite materials were investigated.The results showed that the composite using PAA as the binder exhibited an initial discharge capacity of 564.98mAh/g and an initial coulombic efficiency of 84.6%.After 120 cycles,the discharge capacity remained at 437.70mAh/g,corresponding to a capacity retention of 86.2% compared to the second cycle capacity of 507.97mAh/g.Compared to other binders,the three-dimensional cross-linked network structure of PAA provided the composite with enhanced mechanical strength and structural stability,effectively alleviating the structural degradation caused by the volume expansion of silicon during charge-discharge cycles.
[1] Wu X M,Muhtar D,Zhang D D,et al.Progress of high energy density cathode materials for lithium-ion batteries[J].Chinese Science Bulletin-Chinese,2024,69(20):3024-3046.
[2] Xu Y J,Wang B,Wan Y,et al.Understanding the process of lithium deposition on a graphite anode for better lithium-ion batteries[J].New Carbon Materials,2023,38(4):678-693.
[3] Manthiram A.An outlook on lithium ion battery technology[J].ACS Central Science,2017,3(10):1063-1069.
[4] Wang C,Yang C,Zheng Z.Toward practical high-energy and high-power lithium battery anodes:present and future[J].Advanced Science,2022,9(9):2105213.
[5] Chae S,Xu Y,Yi R,et al.A micrometer-sized silicon/carbon composite anode synthesized by impregnation of petroleum pitch in nanoporous silicon[J].Advanced Materials,2021,33(40):2103095.
[6] Dong H,Wang J,Ding H,et al.Exploring the practical applications of silicon anodes:a review of silicon-based composites for lithium-ion batteries[J].Ionics,2022,28(7):3057-3077.
[7] Yuan L Y,Lu C X,Lu X X,et al.Synthesis and electrochemical properties of nano-Si/C composite anodes for lithium-ion batteries[J].New Carbon Materials,2023,38(5):964-975.
[8] Zhang X,Wang D,Qiu X,et al.Stable high-capacity and high-rate silicon-based lithium battery anodes upon two-dimensional covalent encapsulation[J].Nat Commun,2020,11(1):3826.
[9] Su H,Li X,Liu C,et al.Scalable synthesis of micrometer-sized porous silicon/carbon composites for high-stability lithium-ion battery anodes[J].Chemical Engineering Journal,2023,451:138394.
[10] Li X,Zhang W,Wang X,et al.A stable core-shell Si@SiO(x)/C anode produced via the spray and pyrolysis method for lithium-ion batteries[J].Front Chem,2022,10:857036.
[11] Kim J,Kim M H,Kim Y,et al.Unveiling the role of electrode-level heterogeneity alleviated in a silicon-graphite electrode under operando microscopy[J].Energy Storage Materials,2023,57:269-276.
[12] Berhaut C L,Mirolo M,Dominguez D Z,et al.Charge dyna-mics induced by lithiation heterogeneity in silicon-graphite composite anodes[J].Advanced Energy Materials,2023,13(44):2301874.
[13] Zhang J,Wang D,Yuan R,et al.Simple construction of multistage stable silicon-graphite hybrid granules for lithium-ion batteries[J].Small,2023,19(17):2207167.
[14] Chen Y,Yang L,Guo F,et al.Mechanical-electrochemical modeling of silicon-graphite composite anode for lithium-ion batteries[J].Journal of Power Sources,2022,527:231178.
[15] Liu Y,Shao R,Jiang R,et al.A review of existing and emerging binders for silicon anodic Li-ion batteries[J].Nano Research,2023,16(5):6736-6752.
[16] Li P,Hwang J Y,Sun Y K.Nano/microstructured silicon-graphite composite anode for high-energy-density Li-ion battery[J].ACS Nano,2019,13(2):2624-2633.
[17] Han Z J,Yabuuchi N,Shimomura K,et al.High-capacity Si-graphite composite electrodes with a self-formed porous structure by a partially neutralized polyacrylate for Li-ion batteries[J].Energy & Environmental Science,2012,5(10):9014-9020.
[18] Pietsch P,Westhoff D,Feinauer J,et al.Quantifying microstructural dynamics and electrochemical activity of graphite and silicon-graphite lithium ion battery anodes[J].Nature Communications,2016,7(1):12909.
基金资助
广东工业大学校企合作项目(607220485)
PDF
