Explain Ni Cd battery functioing.

The nickel–cadmium battery (NiCd battery or NiCad battery) is a type of rechargeable battery using nickel oxide hydroxide and metallic cadmium as electrodes. A fully charged Ni-Cd cell contains:

·         a nickel(III) oxide-hydroxide positive electrode plate

·         a cadmium negative electrode plate

·         a separator, and an alkaline electrolyte (potassium hydroxide).

The chemical reactions at the cadmium electrode during discharge are:

    Cd + 2OH^{−−                                                    Cd(OH)}₂ + 2 e⁻

            The reactions at the nickel oxide electrode are:

              2 NiO(OH) + 2 H₂O + 2 e⁻                                      2 Ni((OH)₂  + 2 OH⁻

             The net reaction during discharge is

             2NiO(OH)  + Cd + 2 H₂O                                2 Ni (OH)₂ + Cd(OH)₂

During recharge, the reactions go from right to left

Ni–Cd batteries contain between 6% (for industrial batteries) and 18% (for commercial batteries) cadmium, which is a toxic heavy metal and therefore requires special care during battery disposal. Cadmium, being a heavy metal, can cause substantial pollution when discarded in a landfill or incinerated

Major Features
Cost effective, Reliable safety vent system, Long service life,
Wide temperature range, Excellent permanent charge endurance
 

Major Applications
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Other Applications:      Shavers, Access controller, and so on