From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Explaining the use of a cadmium electrode to test the electrical condition of positive and negative battery plates.
| Identifier | ExFiles\Box 44\5\ Scan013 | |
| Date | 22th April 1926 | |
| EFC. JC.22. X. 4049 22.4.26. X.4049. - RE CADMIUM ELECTRODE. The cadmium electrode is a very useful instrument for showing the electrical condition of the positive and negative plates. Cells which have been in normal use and received correct treatment usually show positive weakness when discharged at normal (10 hour) rate. Cells which are old and have lost a lot of positive active material through the accumulated effect of reasonable charging also show positive weakness. Any cell which has stood for any length of time with the electrolyte low or received bad treatment in any other way shows negative weakness, due to poor capacity resulting from oxidation on the negative plates. When cells are discharged at a high rate they usually show negative weakness even if they show positive weakness when discharged at a normal rate. This means that the negative plates cannot stand up to a high rate of discharge as well as the positives. Cells fitted with threaded rubber separators show negative weakness when the ribs are placed facing the positive plates, but if placed with the flat side facing the positives, they show positive weakness, which tends to show that if the separators were ribbed on both sides it would be better for both elements. Contd. | ||