High performance carboxymethyl cellulose- polyethylene oxide polymer binder for black phosphorus anode in lithium-ion batteries

Black phosphorus (BP) is regarded as a promising anode material due to its high theoretical specific capacity and fast charging safety. However, the problems of huge volume expansion and moderate electrical conductivity may restrict its performance. In this work, we present a novel 3D network binary polymer binder synthesized from carboxymethyl cellulose (CMC) and polyethylene oxide (PEO) for adapt to lithium-ion batteries of BP and graphite (G) composite anode (BP-G). There are the following characteristics of the binder: CMC and PEO are crosslinked through intermolecular forces; while CMC and PEO are connected to BP through strong intermolecular forces, respectively; BP and graphite are connected through PC and POC bonds to form composite anode. So as to form a sturdy structure and effectively accommodate the volume expansion of BP during charging-discharging processes, while avoiding loss of electrical contact between electrode components. Accordingly, the lithium-ion battery shown an excellent electrochemical performance, such as a high initial discharge capacity of 1602 mA h g⁻¹ at 0.5 A/g.