Abstract:Isophorone diisocyanate (IPDI), polyoxypropylene diol (N220), polyhexane adipate diol (PNA), polyadipate-1,4-butanediol diol (PBA) as the main raw material, three waterborne polyurethane (WPU) binders were prepared. Three aqueous polyurethane films were characterized by infrared spectroscopy (IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TG). Their mechanical properties and swelling properties were tested. The electrochemical performance of lithium batteries using these three aqueous polyurethanes as binders was investigated by cycles, magnifications, etc. and compared with batteries using PVDF as a binder. The results show that the tensile strength of waterborne polyurethane film with N220 as soft segment is 11 MPa, the glass transition temperature is -52 ?C, the initial decomposition temperature is 273.6 ?C, which meets the requirements of battery binder, and it is used as a binder. After 200 cycles, the capacity retention rate can reach 97.8%, which is significantly higher than the other three groups.