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).
Letter reporting on the performance of Exide and P&R batteries during a 10,000-mile test on a new Phantom chassis.
| Identifier | ExFiles\Box 54\1\ Scan116 | |
| Date | 2nd September 1926 | |
| X4617P EFCL/T. 2nd. Sept. 1926. Messrs. Peto & Radford, 50, Grosvenor Gardens, London, S.W.1. For the attention of Mr. G.R.N.Minchin. X4617P / E Dear Sirs, On our latest 10,000 mile test chassis - a New PhantomCodename for PHANTOM I - which is nearly on the point of completing the 10,000 mile test, we have had two reports, one at 6,000 miles and one at 9000 miles, and there have been the following remarks relating to the battery which is a sandwich battery of half Exide and half standard P & R cells. The reports are quoted below :- After 6,000 miles:- " The battery is still in good condition. The Exide cells retain the acid much better than the P & R It has been necessary to refill the P & R frequently and at 6000 miles we had to add acid to these to bring them up to the required density. The difference at this mileage of the density being :- Exide specific gravity 1.239 P & R " " 1.189..- These were brought up to S.G.of 1.239. We have during the test run half the miles with no charge; the remainder on charge; and from previous experience of batteries we have not had the amount of evaporation. Very little water has been added generally." After 9,000 miles.:- "We confirm that the Exide cells are better for retaining the acid, more clearance is necessary in the P & R. {Sir Henry Royce} We have not had to add much water throughout the test as there has been less overcharging and consequently less evaporation. We have run half the mileage each day not charging. The condition of battery at finish of test is good. Densities were correct in each cell i.e. Sp. {Mr Spinney} G. 1240." | ||