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).
Specification document detailing requirements for battery separators, plate spacing, and electrolyte management.
Identifier | ExFiles\Box 168b\3\ img019 | |
Date | 22th August 1928 guessed | |
-4- Contd. of ribs and negative plates on the other, or some other means may be adopted to secure a similar result, such as the provision of depressions in the bottom peripheries of each set of plates, arching over each of the pair of supporting ribs, supporting the other set of plates. (Incidentally this method would, for the same depth of sediment space, secure slightly larger active surface than the feet method). The object of this feature is to prevent short circuits by the accumulation of sediment on the supporting ribs. (13) SEPARATORS. The material and thickness of the separators shall be such as absolutely to prevent any possibility of short circuits from plate to plate during the life of the battery. Ribbed wood separators must not be used alone, but with such it will be necessary to insert, in addition, perforated ebonite sheets between the wood separators and the positive plate surfaces. The percentage area of cross section of the perforations must, however, not be so small as to put up the internal resistance of cell so much as to prevent the battery complying with item (2). Careful inspection shall be made of the assembled elements before placing these in the cells originally, to ensure that separators are of uniform and proper dimensions in relation to the sizes of the plates, to prevent the possibility of short circuits occurring by contact or bridging from plate to plate round the edge of the separator. (14) SPACE AT BOTTOM & ABOVE PLATES. Ample space must be provided at the bottom of the cells underneath the plates to allow for the accumulation of all the matter that is likely to be lost by the plates during the life of the battery, without such matter piling up so as to reach the plates and cause short circuit. A considerable space must be allowed above the top of the plates, to prevent the necessity of too frequent topping up, and to allow of the vents being sufficiently clear of the electrolyte so as to minimise the efflux of acid from the vents during charge, and also to provide proper depth of acid to allow for the insertion of the rubber tube of a syringe hydrometer to draw upon the acid for a density reading. (15) OVERFLOW OF ELECTROLYTE. The location of the filler holes and the design of the vents shall be such as to minimise the possibility of the electrolyte coming or spraying out on to the top of the battery during charging, or due to the swerving motion of the car. At the same time, the filler holes should be large enough and so placed as to make the process of filling easily performed without spilling acid on the top of the battery. The filler | ||