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).
Comparison between the proposed P & R BD.11 battery and the standard Exide 6BXFD battery for the 40/50 chassis.
| Identifier | ExFiles\Box 49\5\ Scan333 | |
| Date | 21th November 1922 | |
| R.R. 109 (5000) (SDg9 19-7-22) M/L&S To FN. from EFC. c. Ey. c. EP.{G. Eric Platford - Chief Quality Engineer} X4288 EFC2/T21.11.22. X.3396 - PROPOSED P & R BD.{Mr Berend}11 BATTERY FOR 40/50 CHASSIS COMPARED WITH PRESENT STANDARD EXIDE 6BXFD. X4288 (1) Capacity of battery on 10 hour rate:- Exide 55 - 60. P & R about 70. (2) Short period output:- Discharging through a variable external resistance of 100 ohm, the Exide battery is capable of maintaining a current in excess of 100 amperes for six minutes only - P & R battery for over 10 minutes. Hence there is an improved cranking ability with the P & R battery. In fact our present standard, since the necessary modifications to prevent short circuiting by buckling, does not meet our specification in this respect. (3) Charging rate:- The P & R battery will withstand without damage a considerably higher charging rate than the Exide. (4) Material of cell boxes :- The Exide battery has ebonite cell boxes which are liable to crack and leak. The P & R have Dagenite cell boxes which cannot crack or leak. (5) Box for battery:- The Exide battery requires an additional box. The P & R battery does not require this case, being fixed to the running board by long bolts running down through the ends of the battery case. Contd. | ||