電極黏著劑在鋰離子電池中對於提升電池效能上扮演重要的角色。其主要是將正極材料黏在集電板上，減緩在重複充放電下活性材料的損失。近期研究指出，以導離子型高分子如PAN、PEO、PSS、PNVF作為黏著劑，可以利用其導鋰離子之特性，進而提升電池效能。本研究利用分子動力學模擬，從微觀的角度分析不同功能性高分子黏著劑對鋰離子於正極/電解質界面傳遞機制的影響。
實驗以及商業上常用的PVDF，其高分子骨幹上氟原子與電極表面鋰離子接觸，不易有高分子鏈離開電極表面，阻擋電解質接觸，並使鋰離子接近電極所需自由能較高。而PAN高分子之官能基在支鏈上，使高分子主鏈較易離開電極表面，在電極表面分布廣，使鋰離子接近電極所需自由能較低；此外PAN與鋰離子有吸引力，在電場下由鋰離子帶動高分子，造成高分子結構產生改變。PEO高分子之氧原子在主鏈上，與鋰離子作用力強，並以4~6個氧原子包覆鋰離子；而在電場下由鋰離子帶動，亦會造成高分子分布結構之改變。PSS帶負電易吸引鋰離子，但苯環結構會阻礙鋰離子進出電極，故鋰離子接近電極所需自由能較高。PNVF高分子，可以降低界面電位，更擁有在電場下高分子結構不易改變之特性。
我們從不同結構及動力學性質分析找出各個高分子的特點，並對照實驗上改善的電池效能。PAN有自由能較低之分子特點，可對應於較低的電荷轉移阻抗；PEO與鋰離子有強作用力，可對應高電極材料分散性的結果；PSS在鋰離子漂移速度分析顯示PSS有好的電子傳導性；而PNVF在循環充放電下能保持結構完整性，可對應實驗上有良好黏著性以及耐久性。本研究所提出之分子特性可以提供實驗上在製備黏著劑時可考量的參數，以提升所需電池效能。

This study focuses on the effects of different functional polymer binders on the lithium ion intercalating and deintercalating at the cathode surface of high-power lithium ion batteries (LIBs). We use molecular dynamics (MD) simulations to examine the mechanism of the functional polymers, including polyacrylonitrile (PAN), polyethylene glycol (PEO), poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PSS), and poly(N-vinylformamide) (PNVF), which have been experimentally shown to improve LIB efficiencies. Our results show that PAN can lower the free energy barrier at the surface, which corresponds to the lower charge transfer resistance observed in experiment. The strong interaction between Li+ and PEO can lead to improved dispersion of electrode active materials. The drift velocity analysis indicates that PSS improves Li+ conductivity. Moreover, PNVF maintains structural integrity under charge and discharge cycles, corresponding to a good adhension and an improved battery endurance.

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