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 condition and performance testing of battery cells.
| Identifier | WestWitteringFiles\G\August1921\ Scan49 | |
| Date | 12th August 1921 | |
| Contd. -4- EFC1/T12.8.21. This has been accomplished by placing the cell in one of the supply mains in our laboratory, so that it would be receiving normally about 10 amperes charging current, and occasionally a good deal more than this, perhaps up to 20 amperes in extreme cases. The condition of all the plates of this cell was bad, the positive plates were breaking up and the negatives were unusually soft. There was a good deal of "mud" at the bottom of the cell. The cell had not, however, given out and still gave a discharge capacity of 35 ampere-hours. There were signs of short-circuiting by buckling about to take place, this cell being one of the old standard. There was still a large quantity of active material in the grids and is evident from the fact that the cell gave 38 ampere-hours. Previous to this, though not reported at the time, we had put on a similar cell to be continuously overcharged for about 11 weeks without, however, any intervening discharges. The average charging current was 8 amperes and altogether the charge amounted to about 4300 ampere-hours. This cell, when discharged previous to dismantling, gave 42 ampere-hours, and on dismantling was found to be in quite fair condition, only a little mud having collected at the bottom through a small quantity of active material Contd. R.R. 235a (100 T) (S.H. 159 11-8-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2800 | ||