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).
Potential disadvantages of using threaded rubber separators in batteries.
| Identifier | ExFiles\Box 54\5\ Scan050 | |
| Date | 15th January 1926 | |
| To Wd.{Mr Wood/Mr Whitehead} from EFC. X.3839 - THREADED RUBBER SEPARATORS. Answering your Wdl/NJ14.1.26, we shall look forward to having this battery and the results to be obtained therefrom. As regards the suggested disadvantages of threaded rubber separators:- (1) Introduction of high internal resistance. Our experience so far of threaded rubber separators has not indicated that they do cause high internal resistance at any time of their life, though a true comparison has never been made with two batteries otherwise similar. (2) Development of brittleness if acid level falls below plates. We regard it as a serious matter from the points of view of the plates if the acid level falls below their tops. In fact we are of the opinion that it is a more serious matter for the plates than it would be for the threaded rubber separators. In any case, it is extremely rarely that short circuit by pinching through separators occurs at the top. This, when it happens, is at least half way down or at the bottom. Then again, the brittleness does not seem to matter so long as elements and separators are undisturbed. The great thing is to withstand the pressure of the plates pinching through the separators. Our experience of threaded rubber shows that it stands this certainly better than wood alone, and we think better than with the combination of wood and ebonite. In fact we have known one case at any rate of short circuit by pinching through wood and ebonite. Further, it is not our experience in general with threaded rubber separators that they do become seriously damaged. The only point we feel there may be some difficulty about is as to which way the separators should be turned. If the flat surface faces the positive plates, there may be some disadvantage of extra resistance or chemical action. On the other Cont.d | ||