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).
Letter from a battery supplier discussing the weight, dimensions, and construction of their accumulator.
| Identifier | ExFiles\Box 35\4\ scan 179 | |
| Date | 29th January 1926 | |
| COPY OF LETTER FROM:- THE TUNGSTONE ACCUMULATOR CO.LTD. 3, St.Bride's House, Salisbury Square, Fleet St, LONDON.E.C.4. Our Ref.Wm.H./R.B. 29th January 1926. Messrs. Rolls-Royce Ltd., D E R B Y. Dear Sirs, We have before us your letter of the 25th inst., and we would just like to take the points raised by your Electrician in the order given in that letter. In the first place a great amount of stress has been laid on the disadvantage of our battery in so far that the weight capacity ratio is large. We, ourselves, are quite alive to this, but when designing this battery it was a matter of compromise between strength and rate capacity ratio, and on every occasion with Car Starting Batteries we have aimed primarily at the former; and with "All metal" construction the weight must necessarily be high, but the single benefit derived from the metal container we think outbalances this, namely, that on heavy discharges the rise in temperature of all cells is so infinitesimal that no harmful effect is made on the plates, and it is undoubtedly the rise in temperature of the plate and the electrolyte which causes enormous amount of deterioration of the plate. We would point out that your estimated weight of 130 lbs., for the 75 amp hour battery is high; and the actual weight filled with acid is 114 lbs., The dimensions which you have estimated are also slight out, and actually they are 17" long by 9" wide and 9 1/8" high. Perhaps this reduction in the width on your figure will prove suitable. You raise a very interesting controversial, and in fact, a scientific point when you refer to the leakage across the underneath of the lid{A. J. Lidsey}, and it is a question which we do not wish to enter into with any lengthy - contd - [Handwritten note in left margin]: Very little Heat ? ? | ||