Nickel-Iron Battery

The nickel-iron battery is a rechargeable battery built around nickel oxide-hydroxide positive plates and iron negative plates, with an electrolyte of potassium hydroxide. It is an unusually robust chemistry, tolerant of abuse such as overcharging, overdischarging and short-circuiting, and capable of a very long service life, more than twenty years, even under such treatment, which has kept it in use for backup power installations that can be continuously charged and left in place for decades. Its low specific energy, poor charge retention and high manufacturing cost have nonetheless left it displaced by other rechargeable battery types in most applications where those drawbacks matter more than its ruggedness and longevity.