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).
Results of intermittent high-rate discharge tests performed on a battery.
| Identifier | ExFiles\Box 35\1\ scan 150 | |
| Date | 6th August 1919 | |
| -2- Contd. Further tests consisted in intermittent high rate discharges through the same resistance. In the first of these two, there were alternating periods of 15 secs. on contact and 15 secs. off, in the second, 15 mecs. on and 45 secs. off. In each case the battery started off at 137.5 amperes and maintained over 100 amperes for 9.87 minutes in the first case, and 7.83 minutes in the second, the time reckoned being, not the total time elapsing, but the total time on contact. Finally, we recharged the battery and discharged on a recording voltmeter. The current at the start was just a little over 10 amperes and the discharge was allowed to continue until the slope of the curve made a sudden change in the downward direction, this point corresponding to about 10.2 volts on the terminals at 8.6 amperes discharge, the time to attain this point being 5.80 hours, showing that the capacity was not materially reduced by the high rate discharges. Compared with other batteries we have tested the results given above are only moderately good. We admit that comparison has not been made between this and other batteries in every possible direction such as life tests under vibration, but we hope to do tests of this nature in the near future and probably to put this battery amongst those selected for such tests. Yours faithfully, | ||