黏结剂对Si/C材料电化学性能的影响

Effect of binder on the electrochemical performance of Si/C material

用充放电、电化学阻抗谱(EIS)、X射线光电子能谱(XPS)及SEM等测试,分析海藻酸钠(SA)和丙烯腈多元共聚物(ASA)作为黏结剂对Si/C负极材料电化学性能的影响。10%的ASA作为黏结剂的Si/C体系,具有更高的可逆比容量和容量保持率。Si/C复合材料制备的电池以0.05 C(2 mA)在0.005~2.000 V充放电,可逆比容量达到599.2 mAh/g,库仑效率为83.6%,循环150次的容量保持率达到50.2%。以ASA作为黏结剂的Si/C电极,电化学阻抗较低,循环后电极表面的LiF和Li2CO3含量较低。

The effects of sodium alginate( SA) and acrylonitrile copolymer( ASA) on the electrochemical performance of Si/C materials were studied by the tests of charge-discharge,electrochemical impedance spectroscopy( EIS),X-ray photoelectron spectroscopy( XPS) and SEM.The Si/C system with 10% ASA as binder had higher reversible specific capacity and capacity retention.When charged-discharged with 0.05 C( 2 mA) in 0.005-2.000 V,the reversible specific capacity was 599.2 mAh/g,the Coulombic efficiency was 83.6%,the capacity retention was 50.2% after 150 cycles.The electrochemical impedance of the Si/C electrode with ASA as binder was lower,the contents of LiF and Li2 CO3 on the surface of the electrodes after cycle was lower.