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).
Specification No. 301 for a 40/50 HP chassis lighting and starting 12-volt battery.
| Identifier | ExFiles\Box 54\2\ Scan026 | |
| Date | 8th March 1924 | |
| X4617 EFC1/T8.3.24. SPECIFICATION No.301 OF RR. 40/50 HP. CHASSIS LIGHTING & STARTING BATTERY (12 VOLT) X664 X4617 (1) CAPACITY OF BATTERY. The ampere hour discharge capacity (actual) of the battery at the 10 hour rate should be in the neighbourhood of 75, but certainly not less than 65. (2) & (3) SHORT PERIOD OUTPUT & INTERNAL RESISTANCE OF BATTERY. The battery, at a temperature of 18ºC, should easily be capable of maintaining (supposing the battery nearly or fully charged), a current in excess of 104 amperes through an invariable external resistance of .100 ohm, for a period of 6 minutes, and this without appreciable buckling of, or other damage to, the elements. (4) CHARGING RATE. The design of the grids and separators should be such that the battery is capable of withstanding a charging rate of 12 amperes, when in a fully charged condition, without an unreasonable amount of deterioration of the positive plates. This item is important in connection with battery life. It is realised that provision for this entails some loss of electrical efficiency and weight efficiency. (5) MATERIAL OF CELL BOXES. The material of the cell boxes shall be ebonite of the best possible quality, or alternatively and preferable non-crackable moulded material, perfectly free from any mineral impurities having deleterious action on the electrolyte. (6) CASE FOR BATTERY. The battery should be constructed in a case with convenient attachments for lifting and removing the battery from the battery box. A central stay (bicycle spoke) Contd. | ||