Aqueous processing would reduce the costs and toxicity associated with the making of the composite electrode. In the present study, carboxymethyl cellulose is used as a binder for 5V cathode material LiNi0.4Mn1.6O4. Compared with electrodes using polyvinylidene difluoride binder, CMC-based LiNi0.4Mn1.6O4 electrodes display a better discharge capacity at all rates. At 0.2C, the discharge capacity is close to the theoretical capacity (146mAhg−1) and the self-discharge is 10% lower. Polyvinylidene difluoride can be efficiently replaced by carboxymethyl cellulose for LiNi0.4Mn1.6O4 in terms of electrochemical performance and brings the advantage of an environment friendly and low cost electrode processing.