The combination of lead and copper in a Galvanic cell will produce the highest voltage.
A galvanic cell is actually an electrochemical device that uses a chemical reaction to produce electricity. This device is also called a voltaic cell. It was discovered by Luigi Galvani in 1780.
The Galvanic cell is made using 2 different types of metal. The metal electrode will be immersed in an electrolyte solution of the same metal base. The combination of metal electrodes in the solution is called a half cell. There will be 2 half cells separated by a porous cup or a salt bridge to form the Galvanic cell.
One of the half cells will release cations because of the metal oxidation that takes place. The 2nd half cell will be receive electrons which will combine with the cations to form the metal that will accumulate on the surface of the electrode. Once the electrodes are connected, the electrons will flow from the oxidizing half to the reducing half. The salt bridge or porous cup will help to keep the two different solutions apart while allowing the electrons to pass through so that the circuit is completed.
Always handle chemicals with care. Safety gear (goggles, lab coats and gloves) should be worn when handling chemicals.