本研究使用導電高分子poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS)作為黏著劑，包覆 4-hydroxybenzenesulfonic acid (4HBS)官能基化的矽奈米顆粒作為鋰電池負極材料。經過4HBS官能基化的矽奈米顆粒，與導電高分子藉由電荷吸引力產生完整的包覆。這樣的結構不僅不破壞導電高分子的共軛性(有利於電子導電)，還能有效提升黏著劑的包覆完整性。所產生的矽(核)-導電高分子(殼)的奈米複合材料作為電池的負極，能夠避免矽材料與電解液直接接觸，充放電數圈後形成穩定負極結構，介面阻抗逐漸減小、在充放電500圈後具有穩定的變速率充放電。由以上這些功能能夠有效改善矽基負極半電池的電性表現，減少材料劣化現象和保持矽負極電池的循環壽命。 本研究中發現Si○f25wt%4HBS擁有最好的電性表現，於第105圈時達到最高的電容量2067.7mAh/g，在第500圈時電量下降到1715.1 mAh/g，經過化成後的最高電容量到500圈後的電量保持率為87.0%。在長圈數500圈充放電過程中展現了優異的電容保持率，本研究提供一種新穎的做法來提升電池電化學表現的穩定性，不僅做法簡單價格便宜，此一材料設計概念未來可廣泛應用於鋰離子電池，將可克服以往矽負極劣化的難題。 關鍵字:矽、負極材料、導電高分子、官能基化 ;Conducting polymer poly(3,4-ethylenedioxythiophene) and polystyrene sulfonate polymer mixture (PEDOT:PSS) is used as the binder for lithium battery anode electrode. Complete encapsulation of the binder with Silica nano particle; surface functionalized with 4-hydroxybenzenesulfonic acid (HBS) constitutes a novel high energy anode for advanced lithium battery. The electrostatic interaction between the sulfonic group of HBS and the base electron donating group in PEDOT stabilizes both the silicon nano particles and the conjugate polymer which provide not only fluent electron conductivity but also established flexible protection for Silica nano particle from direct contact with solvent electrolyte. The electron conducting encapsulation eases the concern over the excessive growth of SEI and prevented the pulverization of the active ingredient from repetitive expansion and contraction during charge discharge cycles. For 25% 4HBS functionalized sample (Si f 25wt% 4HBS), a high capacitance in the order of 2000 mAh/g-Si is detected which gradually rose to the highest value of 2067.7mah/g at 105 cycles, and slowly decreased to 1715.1 mAh/g-Si after 500 cycles. The capacity retention rate at 87% is impressive; when compare with all previous anode formula based on conducting polymer encapsulation. Excellent and stable capacity above 1700 mAh/g-Si can be expected when applied to high energy density lithium battery. This study unveils a novel and convenient method to circumvent the stability and pulverization issues associated with the use of silicon nano particle as the anode for next generation lithium battery.
