Toward Greener and Sustainable Li-Ion Cells: An Overview of Aqueous-Based Binder Systems

Lithium ion (Li-ion) cells have gained considerable attention in the past few years as one of the most promising energy storage systems for various applications. Binders, an important component of Li-ion cells, have a crucial effect on the performance of the cells. Considerable efforts have been made recently for the development of cost-effective and environmentally friendly water-based binders for Li-ion cells. However, detailed insight of the aqueous-based binders pertaining to the electrode materials exclusively for Li-ion cells has not been reported yet. This Perspective covers the research and development to date on various classes of organic, polymer-based aqueous binders for various anode and cathode materials, which allows for the replacement of toxic and costly N-methyl-2-pyrrolidone and presents a detailed comparative study of various aqueous binders. The effect of various aqueous binders on different electrode-active materials, especially on electrodes under current development, is also discussed. Furthermore, the impact of the binding agents and the related chemical reactions on the morphology of the electrode, specific capacity, and cycle life is reviewed. This Perspective will surely aid the readers to easily identify and study appropriate aqueous binders for electrode-active materials of their interest.