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To design an electrochemical cell that produces an optimal energy output,…

- - - - Fuel cells
        
        Material such and Hydrogen gas is expensive
        
        only small amounts are generated in an environment friendly manner
        
        Requires external energy/fuel input
        
        Non-spontaneous reactions
        
        Not cost effective
        
        Hence, not an option for this prac
        
        Constant energy output since it does not discharge
      - Secondary cells (Electrolytic cells )
        
        Has a reversible reaction, i.e. the cell can function as a Galvanic cell as well as an Electrolytic cell.
        
        Converts electrical energy into chemical energy
        
        Requires electrical energy/electricity input from a external source
      - Primary cells
        
        Non rechargeable/use-and-throw galvanic cells
        
        The electrochemical reactions are irreversible in nature
        
        Zinc–manganese dioxide cells
        
        Metal–air-depolarized batteries
        
        Reactants are consumed for the generation of electrical energy and the cell stops producing an electric current once the reactants are completely depleted
- - - - Measures the electric potential difference (E°)
        
        A higher voltage means that there is more energy that can be used from the same amount of current.
        
        Calculated by the Nernest equation
        
        The equation E° cell = E° (cathode) - E°(anode)
      - Measures voltage (pressure)
    - - Electric currents are measured in amperes (A)
        
        Count of the number of electrons flowing through a circuit
    - - The pressure/potential electric difference is measured by units of volts (V) and/or amperes (A)
      - The produced electrical energy by electrochemical cells are often measured in watts and/or kilowatts
  - - - Biodegradability
      - Potential harm to environment, e.g water and air pollution
    - - Ability to perform effectively with minimised cost
    - - Longevity
      - Potential of battery corrosion and depletion
- - - - Where oxidation occurs, electrons are loss during the process
    - - Where reduction occurs, electrons are gained throughout the
- - - - Metals often used in batteries (relatively safer options)
        
        Nickel
        
        Copper
        
        Cobalt
        
        Lithium
        
        Vanadium
      - Different types of metal has varying reactivity/ electrical potential. Metals with high electrical potential makes up a high energy density/more efficient battery
      - Examples of high electrical potential metals are nickel, lithium aluminium and zinc
    - - Higher SA:V ratio allows higher rate of reaction
        
        Potentially higher yield of product produced
        
        Higher SA enables the metal to be more exposed to the electrolyte
  - - - Increasing concentration on either of the half cells would cause the system to counteract (Le Chatelier's principle)
  - - - Higher energy obtained by molecules: increase in more successful collisions at right orientation (lower activation energy)
  - - - KCl
      - NaCl
      - NH4NO3
    - - Filter paper
      - Plastic Funnel