Characteristic curve and efficiency of a PEM fuel cell and a PEM electrolyser

Principle

In a PEM electrolyser, the electrolyte consists of a proton-conducting membrane and water (PEM = Proton-Exchange-Membrane). When an electric voltage is applied, hydrogen and oxygen are formed. The PEM fuel cell generates electrical energy from hydrogen and oxygen. The electrical properties of the electrolyser and the fuel cell are investigated by recording a current-voltage characteristic line. To determine the efficiency, the gases are stored in small gasometers in order to be able to measure the quantities of the gases generated or consumed.

Benefits

• Quantitive determination of all relevant parameters
• Production of hydrogen and oxygen which can then be quantified
• Storage of the produced gases in a "gas bar" for reuse

Tasks

1. Recording the characteristic line of the PEM electrolyser.
2. Recording the characteristic line of the PEM fuel cell.
3. Determination of the efficiency of the PEM electrolysis unit.
4. Determination of the efficiency of the PEM fuel cell.

Learning objectives

• Electrolysis
• Electrode polarisation
• Decomposition voltage
• Galvanic elements
• Faraday's law