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).
Specifications and performance comparison of two types of Bentley batteries.
| Identifier | ExFiles\Box 58\4\ Scan101 | |
| Date | 20th June 1933 | |
| 86107. WST To MGR. from E.{Mr Elliott - Chief Engineer} c.c. Hs.{Lord Ernest Hives - Chair} By.{R.W. Bailey - Chief Engineer} H.{Arthur M. Hanbury - Head Complaints} HCY. (Struck through) Hs{Lord Ernest Hives - Chair}/Wst. Wg{Mr Gill - Financial Director}/Wby. (Struck through) re Bentley Batteries. We had Mr Minchin here this morning to discuss the question of the Bentley battery and settle up the remaining particulars of the specification. Hs{Lord Ernest Hives - Chair}/Wst. showed curves of high rate discharge, in which the two types under test, namely, the 9 plate and the 11 plate showed practically equal discharge rates within the first five minutes, and only separated to any extent when the current began to fall away after about 14 minutes. Both batteries, of course, are fitted with double separators of ebonite and wood, but one battery, namely, the 9 has thicker and sturdier plates, which from our long experience on the Phantom 2 and 20/25 we believe make for longer life although the ampere hour capacity is rather less, the 9 plate being about roughly 60 ampere hours at a 10 amp. discharge rate, and 11 - 70 ampere hours on the same rate. Samples of each battery that had been run were opened up and inspected, and we were particularly interested to see whether the separators filled the width of the container, and could not get out of position sideways thereby avoiding the tendency for the plates to pinch the edge of the separator and short. We weighed the elements of one battery against the other, and it was found that the 9 plate elements were 1 lb lighter per cell, representing a total of about 6 lbs per battery, or perhaps slightly less when some adjustment is made for the difference in the acid carried. Mr Minchin thinks he might be able to reduce the weight of the battery lid{A. J. Lidsey} to the extent of one pound by allowing the dies to move closer together. This maintains the rim thickness but reduces the thickness of the top so that a saving of about 7 lbs per battery is within sight. There is no difference between the prices of the | ||