Better cycle stability and rate capability of high-voltage LiNi0.5Mn1.5O4 cathode using water soluble binder

摘要

5 V LiNi0.5Mn1.5O4 (LNMO) cathodes are prepared using carboxymethyl chitosan (CCTS) as a water soluble binder and carbon coated aluminum foils (CAI) as current collector in Li-ion batteries (LIBs). CCTS exhibits an electrochemical oxidation potential as high as 5.0 V. The electrochemical performance of LNMO cathode with CCTS binder is investigated and compared with the commercial non-aqueous polyvinylidene difluoride (PVDF). CCTS-CAl-LNMO electrode shows higher capacity retention (95.8%) than that of PVDF-CAI-LNMO (92.9%) and PVDF-Al-LNMO (88.52%) after 100 cycles. And, CCTS-CAl-LNMO electrode exhibits better rate capability than PVDF-CAI-LNMO, and PVDF-Al-LNMO, retaining specific capacity of 95.8 mAhg(-1) at IOC rate, only 87.6 mAhg(-1) and 1 mAhg(-1) for PVDF-CAI-LNMO, and PVDF-Al-LNMO, respectively. This approach can also be extended its use to other cathode materials such as LiNiii 3Co(1/3)Mn(1/3)O(2) (NCM). (C) 2017 Elsevier Ltd. All rights reserved.