Ludwig Mond and Charles Langer

Ludwig Mond and his assistant Charles Langer were the first to coin the term “fuel cells”. In 1889 they built a fuel cell running on air and industrial coal gas also called Mond gas.Mond and Langer understood Grove’s need for notable surface of action and made significant changes in the experimental design of fuel cells. Firstly, they used a porous non-conducting diaphragm and impregnated it with dilute sulphuric acid, that is, the electrolyte. Next on each side of the diaphragm they placed perforated leaves of platinum coated with a thim film of platinum black. The powdered platinum black served as a catalyst in promoting the reactivity of the fuel cell. At small intervals the platinum leaf was brought in contact with strips of lead. In this manner Mond and Langer reduced the I²R internal losses. Finally the diaphragms so prepared were “placed side by side or one above the other, with non-conducting frames of pasteboard, wood, india rubber, etc, intervening, so as to form chambers through which the gases to be employed (generally hydrogen and air) are passed, so that one side of diaphragm is exposed to one gas and other to the other gas, and the spaces between the diaphragms are sp connected that these gases pass in contact with a number of diaphragms.”

It is easily understood that the modern fuel cells are very similar to the Mond and Langer-H2/O2 cell. With this cell they obtained a current density of 6 A per square foot at a voltage of 0.73 eV. But the cell voltage was found to decrease by 10% per hour of operation and the electrolyte was unable to demonstrate satisfactory invariance.

Mond and Langer indeed paved a way for generating hydrogen from steam reforning of fossil fuels when they found practically no difference in the results whether “using O and H or air and gasees containing 30%-40% of H, such as can be obtained by action of steam or air and steam on anthracite, coke, or coal.”

They clearly outlined the solution of overcoming the much talked about water management issue of todays’d polymer electrolyte membrane fuel cells (PEMFCs) when they said: “With a useful effect of 50% one-half of the heat produced by the combination of the H with the O is set free in the battery, and raises its temperature. By passing through the battery a sufficient excess of air, we can keep the temperature of the battery at about 40 deg C. and at the same time carry off the whole of water formed in the battery by means of the gases issuing from it, so that the Pt black is kept sufficiently dry and the porous plate in nearly the same state of humidity.”

Reference

L. Mond and C. Langer, Proc. Roy. Soc., (London), 46, 296 (1889).: