Wrapping graphite anode via carboxymethyl cellulose bearing with the additive zwitterion molecules as an interfacial layer with high diffusivities for constructing energy-saving battery

This study demonstrates how to construct an energy-saving lithium-ions batteries (LIBs). Through oxa-Michael addition, sulfobetaine methacrylamide (SBMA) is grafted on carboxymethyl cellulose (CMC) as a product, named as CMC-SBMA. Subsequently, CMC-SBMA with the addition of zwitterion molecules, betaine, denoted as CMC-SBMAb which is wrapping around graphite, named as MG-co-CMC-SBMAb. MG-co-CMC-SBMAb is used for anode with lithium metal to be fabricated to LIBs, LIBs-MG-co-CMC-SBMAb whose performances of capacities, resistance of charge transfer (Rct), and diffusivity (DLi+) are compared to those of conventional graphite-based anode with CMC binder (LIBs-MG-CMC). Surprisingly, LIBs-MG-co-CMC-SBMAb possesses the outstanding performance, in line with the high DLi+ and low Rct, compared to LIBs-MG-CMC, being corroborated by the high diffusivity and ionic conductivity of lithium ions within CMC-SBMAb interfacial layer. It shows that lots of zwitterion molecules can enhance lithium ions diffusivity at the interface. Furthermore, MG-co-CMC-SBMAb as anode and Li[Ni0.8Mn0.1Co0.1]O2 (NMC811) as cathode are fabricated to LIBs which is called LIBs-MG-co-CMC-SBMAb//NMC811, demonstrating energy-saving. In that case, zwitterion molecules in carboxymethyl cellulose bearing zwitterion as an interfacial layer wrapping graphite enhance greatly the lithium ions diffusivity to decrease the resistance for energy-saving.