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).
The failure and dismantling of a C.A.V. Willard 12ZR2/7 battery.
| Identifier | WestWitteringFiles\L\July1924-September1924\ Scan89 | |
| Date | 13th August 1924 | |
| EFC. JB.53. 108602. 13.8.24. X.4414V - THE FAILURE OF C.A.V. WILLARD 12ZR2/7. This battery has done a mileage of 8,017 on the road and has since been in the E.M.S. 9 months, broken by three low rate discharges which on each occasion have given poorer results. The last one taken on 24.7.24 only realised 7.8 ampere hours. The battery is now to be opened up for examination. For previous reports refer to JB.9 6.7.23, JB.12 14.8.23, JB.28, 1.1123. Age of battery 31 months. Dismantling of C.A.V. Willard 12ZR2/7. (8C) The following are points noticed in the dismantling of the above battery. General. Sealing compound had run into the cells owing to heat. No sign of corrosion on connecting links, which are of solid lead. Box rotten through with acid, especially where the handles enter the wood. Cell cases separated by sheet cardboard and the whole box filled in with sealing compound. Interior of Cell. A large amount of sediment was found in the cell bottom reaching up to the plates and causing partial short circuit. Negative plates in good condition. Positive plates all broken up, the paste having all fallen out and the grids being rotten. Separators in excellent condition. The cell cases are likely to crack. The age of this battery is 31 months. For previous reports see JB.53 13.8.24. This battery did not fail by definite short circuits, but by loss of capacity due to the positive paste having fallen out. Also there was no sign of buckling. EFC/GJ. | ||