They are batteries in which the positive electrode is nickel hydroxide and the negative electrode can be cadmium (Ni-Cd) or hydrogen absorbing alloys (Ni-MH). Despite the development of new technologies in recent years, Ni-Cd or Ni-MH batteries still have their space. Nickel batteries can not compete in energy density with lithium batteries but they stand out in some aspects such as robustness, number of cycles, endurance, etc. Nickel batteries have a prominent role in industrial applications where the robustness predominates over weight or volume.