Electrochemical Reactions
Anode: Electrons are lost due to oxidation. (negative electrode) Cathode: Electrons are gained due to reduction. (positive electrode) Electrolyte: The medium that carries the ions or electric charges. Separator: Keeps electrodes from touching. (cloth or paper) Collectors/electrodes: collects current to be used in the outside circuit.
Cu Zn SO 4 -2 Cu +2 Zn +2 Cu +2 Zn +2 e- e- Zn +2 e- e- Loss of electrons OXIDATION Gain of electrons REDUCTION
All of the “batteries” pictured are really just single POWER CELLS. They have only one cathode and one anode. All of these power cells have a voltage of 1.5 regardless of size!
A true BATTERY is actually several power cells connected together. A 9-volt battery is six 1.5V power cells connected to each other. A car battery is a combination of enough power cells to equal 12 volts.
Most electronic devices run on a combination of power cells. This combination can increase the life of the battery or increase the voltage supplied to the circuit.
Energy is needed to move electrons in a circuit. A power cell does not provide electrons to the circuit because the electrons already exist in the conducting wires of an electronic device. A power cell simply provides the energy needed to move electrons that already exist in a circuit.