Battery Anode Material

• A nickel-cadmium battery contains a nickel anode. This electrode serves as the positive battery terminal.
  
  

Battery Cathode Material

• A nickel-cadmium battery contains a cadmium metal cathode. This electrode serves as the negative battery terminal. Cadmium is toxic; therefore, when a nickel-cadmium battery can no longer be recharged, many jurisdictions require the battery to be returned to an authorized recycling center rather than to be disposed of as household garbage.
  
  

Battery Electrolyte

• The electrodes in a nickel-cadmium battery are placed in contact with a potassium hydroxide paste. This alkaline paste reacts chemically with the nickel anode and the cadmium cathode to create a voltage differential. Over time, this electrolyte will begin to combine with the electrode materials and the battery will begin to lose the ability to provide electrical current. When the battery is recharged, the combination process is reversed and the battery can provide electrical current as before.
  
  

Nicad vs. Alkaline Battery

• Alkaline batteries operate at higher voltage than nickel-cadmium batteries (1.5 volts per cell vs. 1.2 volts for a nickel-cadmium battery). However, alkaline batteries are designed to be used once, whereas nickel-cadmium batteries can be recharged and reused hundreds of times.