Cells and batteries

• Cell

  Two different metals placed in an electrolyte to produce electricity
• Producing electricity in a cell

  1. Chemical reaction on the surface of the two metals

  2. Potential difference and electric current generated
• A simple cell does not generate electrical current for long
• Cells only produce electricity if metals with different reactivity are used
• Difference in reactivity between metals

  Determines the potential difference produced by the cell
• Battery

  Two or more cells connected in series to produce a greater voltage
• Alkaline (non-rechargeable) batteries

  • Reactants run out, cannot reverse the chemical reactions
• Rechargeable batteries

  • Chemical reactions can be reversed by applying an electrical current