Nickel-zinc batteries make use of alkaline electrolytes and rely on hydroxide as main charge carrier. Thus, they offer high power-densities and long cycle life. Research on nickel-zinc batteries has paused due to low practical capacities.
Zinc metal is a versatile, high-energy, and low-cost electrode material. These advantages have made zinc metal electrodes appealing for a wide range of battery chemistries like zinc-air, zinc-ion, and zinc-flow batteries, shown respectively in Fig. 2.
This industry-leading power density and small footprint is achieved through the fast electrochemical and transport kinetics of the nickel and zinc electrodes, combined with the highly conductive non-flammable aqueous electrolyte and a cell design that minimizes internal losses.
Nickel–zinc has been invented in 1899 and produced commercially from 1920. The positive electrode also uses the same material, and for the anode electrode, a pasting of zinc oxide is used. Due to the high cell voltage, the energy density is about double of the nickel–cadmium and nickel–iron-based batteries. At the positive electrode,
The nickel based batteries are mainly the nickel–cadmium (NiCd), the nickel-metal hybride (NiMH) and the nickel-zinc (NiZn) batteries. All three types use the same material for positive electrode and the electrolyte which is nickel hydroxide and an aqueous solution of potassium hydroxide with some lithium hydroxide, respectively .
Pasted zinc electrodes are porous electrodes which are often used in commercial cells with alkaline electrolytes. The electrode is manufactured in a discharged state from ZnO and other additives such as bismuth oxide and calcium hydroxide, for use in an alkaline environment. They were first used in nickel-zinc batteries [ 85, 86 ].