Overview of the functional binders in high-capacity cathodes of lithium-ion battery

High-capacity cathode materials for lithium-ion batteries (LIBs), typically represented by nickel (Ni)-rich and lithium (Li)-rich layered oxides, have been regarded as promising candidates for high-performance LIBs owing to their potential to achieve energy densities of up to 400 Wh kg-1. However, challenges such as interfacial instability, bulk structural degradation, dissolution of transition-metal ions, and undesirable side reactions occur during cycling, necessitating strategies to enhance their electrochemical performance. A LIB generally consists of a cathode, anode, electrolyte, separator, and various inactive components, including binder, current collector, and conductive agents. Although the binder constitutes a small portion of the electrode system, it plays a pivotal role in determining the electrode’s electrochemical performance. The utilization of functional binders has proven to be an effective strategy for mitigating the aforementioned challenges associated with Ni- and Li-rich layered oxides. This review provides a comprehensive analysis of emerging binders for Ni- and Li-rich layered oxides, highlighting the effects of functional groups and discussing noteworthy research directions in cathode binder development.