锂离子电池硅负极水性粘结剂的制备和电化学性能研究

Abstract

硅在众多锂离子电池负极材料中具有最高的理论比容量、较低的嵌脱锂电位和丰富的自然储量，有望在新一代高比能量锂离子电池中得到商业化应用。然而硅在充放电过程的较大体积变化会严重影响电极循环稳定性。本论文通过改性提升粘结剂机械强度以及开发新型粘结剂，缓解其体积效应，从而提高硅负极循环性能。论文研究的主要结果如下： (1)通过海藻酸钠与金属离子的配位交联反应制备出一系列复合粘结剂，并将这些粘结剂首次用于锂离子电池硅负极。其中使用Al3+、Ba2+离子与海藻酸钠复合获得的粘结剂表现出较高的机械强度，使用这两种粘结剂的电极在420mAg-1电流密度下经300次循环后保持的可逆容量约为2100mAhg-1；...

Si is a promising anode material for next-generation high energy density lithium-ion batteries due to its high theoretical capacity, relatively low Li+ insert potential and nature abundance. However, Si anode has unstable cycle performance because of the huge volume change during charge/discharge processes. In this study, we have tried to improve the electrochemical properties of Si anode by prepa...