Publisher Summary This chapter discusses the features and usage of various types of nickel batteries. Different types of nickel batteries discussed are nickel-cadmium secondary batteries, nickel-zinc secondary batteries, and sodium-nickel chloride secondary batteries. Nickel-cadmium secondary batteries are available in open and semi-open smaller types and sealed. The nickel-cadmium battery is the type used almost exclusively for engine starting in larger aircraft. Nickel-zinc batteries are the batteries of the future in applications, such as utilities load leveling and electric vehicles, and indeed the nickel-zinc battery is commercial production in the USA. The 2.6V sodium-nickel chloride battery is at the pilot plant production stage as a possible battery for electric passenger vehicles and buses.