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).
Car battery charging issues and categorizing them into four distinct groups.
| Identifier | ExFiles\Box 164\3\ img104 | |
| Date | 7th January 1938 | |
| To By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to Mx.{John H Maddocks - Chief Proving Officer} c. to Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} 6021 Rm{William Robotham - Chief Engineer}/RC.{R. Childs}10/JH.7.1.38. BATTERY CHARGING ON CARS. As a result of Mr. Minchin's letter, under covering note Rm.{William Robotham - Chief Engineer}10/R.6.12.37. and memo. Byl4/G.8.12.37. we have gone carefully into this matter. We first note that Mr. Minchin did not know his battery was being undercharged, until it had completed 2.5 years service, and had apparently come to the end of its life. Therefore, to all intents and purposes his battery was maintained in a fairly well-charged state, and his dynamo-regulator-battery system satisfactory. He is concerned with the fact that his batteries would probably have a longer life if they were given the occasional "gassing" charge, which is necessary to keeping the battery in the best condition. With this latest criticism, we can generally divide dynamo-battery charging troubles into four groups as follows - (1) Battery run down through excessive starting, and parking with lights on; and low speed running in traffic. (2) Battery run down through long periods of running with a load greater than the supply, resulting in a steady discharge. (3) Short life of battery through premature buckling and short circuiting of plates or shedding of active material, as a result of excessive overcharging. (4) Short life of battery through deterioration of plate surface, due to the inability of the system to provide a "gassing" charge. As regards group (1) we can do little for this type of owner, beyond fitting a charging plug-socket, and recommending some method of charging from an external source; because this trouble is due to sheer lack of running at a charging speed. A higher charging rate of course would help, groups (2) and (4) would be satisfied by a higher charging rate, but this remedy | ||