Characteristics of Ni-Zn Rechargeable Batteries with Zn Anode Prepared by Using Nano-Cellulose as its Binder Agent

Abstract

While the operating voltages of Ni-Zn batteries are smaller than Li-ion batteries, Ni-Zn batteries offer some advantages, such as high specific energy and low cost. Ni-Zn batteries use green materials as they use aqueous electrolytes and do not need hazardous organic solvents. Both Ni and Zn are abundant and much less expensive in comparison to lithium. Therefore, Ni-Zn batteries are more suitable as secondary batteries for applications that do not need mobility, such as for storing electricity from solar panels at home or office building. At present, large scale usage of Ni-Zn batteries is hindered by their low life cycle due to Zn anode degradation during the operation. The Zn anode deteriorates as dendrite and passivation growth causing self-discharge at the Zn anode. Many efforts have been tried to solve those problems by adding additives in the electrode or electrolyte and a specific binder in the Zn anode. In the present work, in addition to standard CMC and PTFE as the binder in Zn anode, we also added nano-cellulose as its binder agent as the host matrix may be formed with a much smaller void, providing much more dispersion of ZnO nanoparticles and better reduction on Zn dendrite formation. The battery structures in this work were Zn-anode | electrolytes (KOH, aqueous) | Ni-cathode. Ni cathode used in this work is similar to those found in commercial Ni-Zn batteries. The Zn anode was prepared with various compositions of binder and hydroxides, such as Ca(OH)2, and ZnO nanoparticles as the active materials. The characteristics of the batteries are largely affected by the composition of the binder and other substances forming the Zn anode, particularly the proportion of the hydroxide. However, in general, the present result shows the potential of this modified Ni-Zn battery as an alternative to supersede expensive Li-ion batteries for low-cost and stationary applications.