Performance of two batteries and inquiring about ordering new ones from Peto & Radford.
| Identifier | ExFiles\Box 38\5\ Scan130 | |
| Date | 2nd September 1921 guessed | |
| EFC {E. Fowler Clarke - Electrical Engineer} 2/T. -2- Contd. The first mentioned battery just fell short of this performance by a little bit, starting off a little lower than 137 amperes, but otherwise just met that condition. The second battery also started off a little lower than 137 amperes, but otherwise was much higher in performance than that specified, e.g. the discharge was still 129 amperes after a period of 5 minutes. The initial current in this test is, of course, reciprocally a measure of the internal resistance of the battery and a statement to the effect that the initial current should exceed 140 amperes amounts to saying that the initial battery terminal voltage at this current should not be less than 10V. Although we do not now attach much importance to the weight efficiency of these batteries in ampere-hours per pound on low rate discharge, knowing that some of this was sacrificed for the purposes of durability and also possibly for those of immunity from leakage of charge, we do, however, still attach considerable import-ance to the internal resistance, i.e. to capacity for high rate discharge without excessive drop of voltage, at any rate for short intervals. As a result of the satisfactory performance of these two batteries on the cars, our Chief Engineer has notified us that he would be further interested in batteries of your make, and it is with this in view that we are now writing you. We have received information that the material of which your cell boxes are now made cannot crack or split, even if dropped on a concrete floor, so that leaks presumably cannot develop in the cells. Further, that you have introduced in the cells the independent support of the positive and negative elements, together with related modifications. We should, therefore, like you to inform us as to what type of Peto & Radford battery you would recommend to us, after which it is probable that we should instruct our Order Office to place with you an order for two such batteries. Contd. | ||
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).