The progress of two special Exide batteries with a specific cell design.
| Identifier | ExFiles\Box 54\2\ Scan154 | |
| Date | 11th June 1926 | |
| To ROY. {Mr H. Royce - Buyer} from EFC. {E. Fowler Clarke - Electrical Engineer} X467/8 EFC {E. Fowler Clarke - Electrical Engineer} 1/T11.6.26. X.4617E. EXIDE BATTERIES. Answering your ROY {Mr H. Royce - Buyer} /Ms5/P10.6.25, the only enquiry we wish to make of Mr. McKinnon is with reference to the progress of the two special 40/50 6RR5/1 batteries, made up with alternate cells having trangular bars with their apices facing inwards and outwards respectively. EFC. {E. Fowler Clarke - Electrical Engineer} | ||
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).