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).
Battery charging and performance test log with cell-by-cell readings.
| Identifier | ExFiles\Box 52\4\ Scan054 | |
| Date | 25th May 1929 guessed | |
| -4- Contd. Date. (16) Fourth charge:- Charge given:- 7 amperes for 12 hours = 84 ampere hours. Cell No. | 1 | 2 | 3 | 4 | 5 | 6 Density. | 1280 | 1280 | 1280 | 1280 | 1280 | 1280 Voltage. | 2.7 | 2.7 | 2.7 | 2.7 | 2.7 | 2.7 +ve to cadmium. | 2.4 | 2.4 | 2.4 | 2.4 | 2.4 | 2.4 -ve to cadmium. | -.3 | -.3 | -.3 | -.3 | -.3 | -.3 (17) Battery temperature:- 66°F 19°C. Ampere-hours realised up to point where record takes a sudden turn down:- 70.7 Cell No. | 1 | 2 | 3 | 4 | 5 | 6 Density. | 1100 | 1100 | 1100 | 1100 | 1100 | 1100 Voltage. | 1.75 | 1.75 | 1.75 | 1.75 | 1.75 | 1.75 +ve to cadmium. | 1.95 | 1.95 | 1.95 | 1.95 | 1.95 | 1.95 -ve to cadmium. | .2 | .2 | .2 | .2 | .2 | .2 (18) Fifthe charge :- Charge given:- 7 amperes for 20 hours = 140 ampere hours. Cell No. | 1 | 2 | 3 | 4 | 5 | 6 Density. | 1280 | 1280 | 1280 | 1280 | 1280 | 1280 Voltage. | 2.7 | 2.7 | 2.7 | 2.7 | 2.7 | 2.7 +ve to cadmium. | 2.4 | 2.4 | 2.4 | 2.4 | 2.4 | 2.4 -ve to cadmium. | -.3 | -.3 | -.3 | -.3 | -.3 | -.3 Dates in right hand column: 26-6-29 to 27-6-29 27-6-29. 28-6-29. 28-6-29 28-6-29 to 29-6-29 | ||