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).
Examination and comparison report on a Delco 15-T9 battery.
| Identifier | ExFiles\Box 164\3\ img157 | |
| Date | 5th April 1938 | |
| Delco 15-T9 battery received from Messrs. Rolls Royce. The weight of this 6 volt Delco battery complete with acid is 39 1/2 lbs. We obtained 13.1 hours discharge at 5 amps, the following readings being taken at the end of this period: 1 2 3 Cell No. 1.74 1.835 1.825 Cell voltage 2.07 2.08 2.08 Positive - cadmium voltage Negative " " .35 .25 .26 Specific Gravity 1.105 1.115 1.105 The capacity obtained, 65.5 ampere hours, is only slightly more than half the rated capacity, and in view of the poor performance and of certain indications which seemed to show a tendency to short-circuits in the cells, we opened up the battery for examination. We found the positive plates to have grown and fractured, and the negative plates to be in a badly sulphated and granular condition. The wood separators were charred and brittle, and it was obvious that the battery was beyond repair. In view of the poor condition of the plates and separators the ouput we obtained cannot be regarded as typical of the battery when new, but on the other hand the rated capacity of 120 ampere hours is more than the battery could be expected to give. For comparison purposes we give below details of the Delco battery alongside particulars of our nearest equivalent 3-GX15 battery:- DELCO 15-T9 P. & R. {Sir Henry Royce} 3-GX15 Dimensions of: Positives 5.11/16" wide x 5" x .093" 5.11/16" x 5" x .093" Negatives 5.9/16" " x 4 7/8" x .072" 5.11/16" x 5" x .093" Wood separators 5.13/16" " x 5 1/4" x .060" 5 7/8" x 5 7/8" x .079" Diaphragm thickness .039" .039" Internal dimensions of cell 5.15/16" wide x 2.3/8" x 5.15/16" x 2 3/4" x 7.7/16" containers. 7.7/16" high Container overall 9" long x 7" wide x 10.5/16" long x 6 3/4" wide 7 7/8" high x 9 1/2" high Our height includes handles. | ||