Chemical cells and fuel cells

what are chemical cells?

stores of internal energy that can be transferred as an electric current in a circuit

what effects the voltage of a cell?

• what the electrodes are made from

• the substances used as the electrolyte

how can a cell and battery be made?

• connecting two different two different metals in contact with an electrolyte

• a battery can be made by connecting a number of cells in series to make a battery, which provides a greater voltage

what happens in a non-rechargeable cell or battery?

the chemical reaction stops when one of the reactants has been used up

ex) alkaline batteries

what happens in a rechargeable cell or battery

the chemical reactions are reversed when an external electrical current is added

what are fuel cells?

devices that produce a voltage continuously when supplied with a fuel and oxygen

how does a fuel cell work?

• hydrogen loses electrons at the anode (oxidation)

• H+ ions in the electrolyte move to the cathode

• electrons flow through an external circuit from anode to cathode

• at the cathode, oxygen gains electrons and reacts with H+ to form water (reduction)