Used in electroplating to deposit a protective or decorative layer of nickel on metals, enhancing corrosion resistance and surface hardness, particularly in industries such as automotive, electronics, and household appliances. Commonly employed in the production of batteries, especially nickel-cadmium and nickel-metal hydride types, due to its role in forming active electrode materials. Serves as a catalyst precursor in industrial chemical reactions and as a mordant in textile dyeing to improve color fastness. Also utilized in the preparation of other nickel compounds, in microbiology as a component of some growth media for bacteria requiring nickel ions, and in agriculture in small amounts to supplement soil nutrients. Additionally, used in research laboratories to study the properties of nickel compounds.