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).
Continuation sheet discussing battery performance, charging, deterioration, and fault diagnosis using Ampere Hour Meters.
| Identifier | ExFiles\Box 54\2\ Scan229 | |
| Date | 24th May 1928 guessed | |
| Continuation No.2. charging at the normal rate it is charging at an increased rate when the Battery is fully loaded and this is where we assume the risk of overcharging occurs. From our prolonged tests we can definitely state that our Battery Ampere Hour Meters and Indicators will give a reasonably accurate reading when a Battery is not in first class condition. A Battery gradually deteriorates from its original 10 hour rate and will not retain its charge. From observations of our Instruments fitted on a car under actual working conditions, they definitely indicate over a scale area the amount of charge that the Battery will retain. For example, when a Battery has deteriorated to say 40% of its original 10 hour rate, the length of time for re-charging a Battery in this condition may be 3/4 of an hour. A further prolonged charge of say 6-7 hours (with the object of increasing its capacity) will not be retained by the Battery. Although a Battery may have deteriorated in its capacity it will still be able to respond to its work, but it will require charging more frequently, and our Instruments are just as reliable when fitted in circuit with a Battery in this condition for indicating the state of charge as when connected to a new Battery. Of course if these Instruments are fitted when the Battery is new the risk of overcharging is reduced and it enables the owner to obtain 100% efficiency from a Battery. The following faults have been revealed through the use of these Instruments. Battery terminal corroded causing leakage to case. Broken cell partition causing leakage from one cell to another. Acid density incorrect. Plates not covered with Electrolyte. Piece of copper wire connecting cell to case causing leakage etc. These Instruments are calibrated to the Battery Makers instructions and the correct charge rate and acid density specified on the Battery must be adhered to, otherwise if the Battery is being charged at a greater | ||