現階段矽基材料已成為鋰電池負極研究熱點，矽負極材料其優勢為提升鋰電池能量密度，其理論電容量高達4200 mAh，不過此材料的電化學循環壽命極差。在許多文獻研究已指出，原因來自充放電時矽本身與鋰的合金反應，而造成龐大的體積膨脹，進一步在表面形成裂縫，新的裂面則與有機溶劑再形成更多的SEI層。體積膨脹也使其電及結構機械性質弱，易造成活性物質與基材剝落，進而喪失電化學活性。因此，本研究為開發新型水性黏著劑，以聚矽氧烷(Poly(methylhydrosiloxane), PMHS) -[Si-O]-為主架構組成之聚合物，具備優異親水性、耐熱性、低收縮、柔韌性等特性，對於需具備耐熱性的鋰離子電池有其應用之優勢。並以不同相位的苯基雙馬來醯亞胺((N,N-Phenylene) dimaleimide)以及聚乙二醇甲醚(Poly(ethyl glycol) methyl ether methacrylate, PEGMEMA)合成於聚矽氧烷上。雙馬來醯亞胺結構，可形成高還原電位的高離子導電SEI，另一端則為聚乙二醇甲醚，主要以EO提供離子跳躍的平台協助離子傳輸的功能。此結構設計，期盼能藉此抑制矽基負極材料之膨脹性，使其發揮高電容量特性，並提高矽負極鋰電池之循環壽命。
在本實驗結果中，電池性能測試方面，其添加MI4M950之添加劑，在第20圈充放電後電容量仍維持在1500 mAh/g，其結果遠優於空白組的500 mAh/g。充放電後的極片形貌測試可觀察出，其添加之極片生成物猶如珊瑚礁般，連結著粒子與粒子之間。本研究更結合了臨場電化學分析，與國家同步輻射中心合作之臨場穿透式X光顯微鏡，其高強度光源帶來的數據結果，明顯觀察出添加新型水性黏著劑其抑制矽顆粒膨脹之效果。另外，本實驗室也開發了臨場電化學傅立葉轉換紅外光光譜儀，在充放電過程中進行矽表面化學組成的分析，進而了解其表面組成的變化。

Many researches have been found the main drawback of Si-based anode materials. It is believed to be responsible with the cracking and pulverization of silicon structure during the lithiation and delithiation process. The volume changes that can be up to ~300% compared to the original size able lead to several degradation processes such as mechanical strains, loss of electrical contact between the different anode materials, and to the current collector. Furthermore, the continuous volume change of Si can cause the cracks on the surface area. However, its practical application is limited by structure degradation.
In this study, a new compound has been developed, which is combined with the functions of SEI formation and particle adhesion in electrode. This new technology is used to eliminate the huge irreversible reaction on first cycle and effectively extend the cycle life. The new compound was composed by the (N,N-Phenylene) dimaleimide and the Polymethylhydrosiloxane (PMHS) through Hydrosilylation reaction. The functionalized aqueous product provides three performances including excellent adhesion property with silicon particles on backbone structure, high ionic conductive SEI with high reduction potential on imide structure, and ionic hopping site on acrylate ethyl oxide side chain. It is the first time that combines binder, SEI, and ionic transfer functions in one material in order to solve the uneven distribution of electrochemical reaction on silicon particles. In addition, we anticipate that the volume expansion and irreversible reaction on silicon can be effectively eliminated by this new technology.
According to the results, the functionalized aqueous binder additive The charging-discharging tests of the MI4M950 additive showed better perfoemance, 1000 mAh/g specific capacity at 0.2 C rate after 20 cycles. The electrode morphology test, scanning electron microscope (SEM), observed that the MI4M950 electrode surface cover by the SEI layer, the shape like a coral, which is connected between silicon particles. In this study, combined with the In-operendo TXM and In-operendo FTIR-ATR, these two powerful instruments give us more information during the C/D testing. The resultant anodes, the MI4M950 additive cell have excellent adhesion to Si micro particles and current collector, ductility and more importantly, endure dramatic volume changes of Si thereby prohibiting physical fracture during lithiation/delithiation processes.

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