Novel Aliphatic polycarbonate binders for Solvent‑free manufacturing High‑loading cathodes of high-performance lithium-ion batteries

Abstract

To achieve high energy density lithium-ion battery depends on high area load of the active material in the cathode. However, it is challenging to attain high loading of active material by traditional wet coating method due to large amount of organic solvent used. A solvent-free manufacturing cathode that take advantages of viscous flow polymer binder under shearing force of ball-milling to bind the active materials and the conductive carbon uniformly on the current collector is an environment-friendly alternative and has attracted increasing attention. Herein, a solvent free manufacturing LiFeO4 cathode with thermoplastic polymer poly(lactide-co-propylene carbonate) as functional binder has high area loading up to 57 mg/cm2 of active material, and the battery assembled with such a LiFeO4 cathode and lithium metal anode can release a specific capacity of 135.5 mAh/g at 0.2C. In addition, the cathode using poly(propylene carbonate) or polycaprolactone functional binder can also be loaded with 40 mg/cm2 of active material, which expands the variety of binders for solvent free manufacturing electrodes. Solvent free manufacturing electrodes with such functional binders are expected to break through the technical bottleneck of lithium-ion battery with high energy density.