21.4    Cells and Batteries

Rechargable and non-rechargeable cells

• Batteries are electrochemical cells used as portable sources of electricity
• • Primary cells cannot be recharged and are discarded once the supply of electric current decreases. This happens when the concentration of reactants becomes too low.
  • Secondary cells can be recharged over and over This involves converting the products back to the reactants produced when delivering the current by electric current.

Dry cells 

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Lead-acid accumulator

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Hydrogen-oxygen fuel cells

 

 

 

 

 

 

 

 

 

 

 

 

Electric cars