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 of C.A.V. Willard batteries for the U.S.A. market, detailing specifications and cell arrangement.
| Identifier | ExFiles\Box 51\5\ Scan143 | |
| Date | 6th May 1921 | |
| S.S. 85a (100 T) (S.H. 798. 10-12-20) G. {Mr Griffiths - Chief Accountant / Mr Gnapp} 1047 Contd. -4- EFC {E. Fowler Clarke - Electrical Engineer} 3/T6.5.21. X.3654. C.A.V. Willard battery for U.S.A. The C.A.V. Company informed me that the Willard Co. in U.S.A. are supplying the American R.R. Co. with Willard thread rubber, 80 ampere-hour batteries, type SJR.G.28 which corresponds exactly to the C.A.V. Willard 12 XR4. This battery has an arrangement of cells in accordance with the following sketch; with terminals near together at one end in a manner we do not consider good. Further it is a larger and heavier battery than the one we are proposing for standard over here, namely, 12 XR3, this only being rated at 64 ampere-hours. We were not aware of the standardisation of this battery by R.R. Inc., until we were informed by the C.A.V. Co. The vent supplied on the smaller battery 12XR2 is somewhat different from the one on 12ZR3 as per sample. The ampere hour capacities and number of positive plates of the batteries are as follows :- Battery. Weight with acid. No. of positive Plates. Ampere-hours. 12 XR 2 99 probably. 3 48 12 XR 3 82 1/4 4 64 12 XR 4 66 1/4 5 80 EFC. {E. Fowler Clarke - Electrical Engineer} | ||