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).
Assessment report on the good and bad points of a De Martis accumulator.
| Identifier | WestWitteringFiles\F\April1921\ Scan61 | |
| Date | 6th April 1921 | |
| To R.{Sir Henry Royce} & E.{Mr Elliott - Chief Engineer} from EFC. c. CJ. & BJ. c. PN.{Mr Northey} c. By.{R.W. Bailey - Chief Engineer} & Bn.{W.O. Bentley / Mr Barrington} c. Da.{Bernard Day - Chassis Design} & EP.{G. Eric Platford - Chief Quality Engineer} c. EWT. for R.R.Inc. ORIGINAL. EFC2/T6.4.21. X.3629 - RE DE MARTIS ACCUMULATOR. This battery was received by us on February 22nd, and some preliminary remarks with reference to this battery were included in our report EFC3/T7.3.21. The considered good and bad points of this battery are as follows :- 1. The cell to cell connections are burnt up and finished with black enamel in a way which gives a good solid appearance, but otherwise the cells are detached. 2. The battery is fitted in a case with lifting handles, but the terminals, which consist of brass nuts, bolts and washers, are on the outside of the battery at one end and are therefore free from acid spray, but would be somewhat inconvenient for making connections on the car. 3. The cells do not appear to be a good fit in the box and are therefore liable to some relative motion when on the car. 4. The separators which are of perforated corrugated ebonite seem good. 5. The passages of the lugs through the cell lids appears to be carried out in a satisfactory manner. 6. The vents are of ebonite and experience has shown that these allow of acid spraying on the top of the battery. The general finish of the battery is very fair. 7. The top of the battery is considered unsatisfactory as the top of each cell gives a depression in which acid and dirt will collect. 8. The battery is not suitable for standardisation for the R.R. car without modification. 9. We are of the opinion that the sealing-compound with which individual cell lids are fixed is too hard. In our experience it is liable to crack and allow acid to percolate out to the top of the battery. In cells in which a softer sealing compound is used, so plastic as that a depression Contd. (upside down text at bottom) R R 285A (50 T) (S.H. '986. 19-2-21) 300S | ||