Electrochemical cells

• Cells in which an electrochemical reaction can occur have been designed to provide useful electricity
• Electricity can be generated by chemical reactions
• Cells

  • Electrochemical cells
• Uses for electrochemical cells

  • Torches
  • iPods
  • Cellphones
  • Remote controls for gates, TV sets and other electronic devices
• Electrochemical reactions


  Chemical reactions that can generate electricity
• Using fruit juice or a salt solution to make an electrochemical cell produces so little electrical current that you cannot tell if it is producing electricity without connecting it to a very sensitive electric meter
• Structure of an electrochemical cell

  Made from a copper coin and a nickel coin, conducting liquid is the juice inside half of a lemon, connected to a multi-meter to indicate electric current flow
• Vinegar is a better conducting solution than fruit juice as it is much more acidic and supplies enough electrical current to make an LED shine when the cell works
• Advantage of connecting cells in series is that they provide a higher voltage than one cell alone
• Connections in series and parallel

  Cells can be connected in series or parallel
• Advantage of connecting cells in parallel is that if a cell is disconnected or removed, the other cells continue to supply energy to the circuit
• Things to make an electrochemical cell from

  • Juices of acidic fruit such as lemons and grapefruit, solution of salt in water, coins made from two different metals
• Disadvantage of connecting cells in series is that if one cell is disconnected or removed, it breaks the circuit loop and the current stops
• Connecting batteries of two cars in series should not be done on recent model cars as it could destroy the mini-computers that control their electrical systems
• Electrochemical cells


  Consist of a liquid or substance that conducts electric current and two metal parts called electrodes immersed in the liquid
• Electrodes


  • Parts where connections are made to an electrical circuit
• Jump-starting a car is done by connecting the battery of another car in parallel with the flat battery of the older car
• Disadvantage of connecting cells in parallel is that the voltage of the circuit remains the voltage of one cell, no matter how many cells are connected in parallel