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 for battery cell sealing compound and plate grids.
| Identifier | ExFiles\Box 54\2\ Scan029 | |
| Date | 8th March 1924 | |
| X4617 -4- Contd. (12) SEALING COMPOUND. The cells should be completely sealed over their tops only. This means that sealing compound should not be allowed completely to fill the interstices between the cell boxes and between the cell boxes and the battery case, but only to cover up the tops of the cells in such a manner that there is no possibility of acid getting down to these interstices. The object of this is the easier removal of individual cells. In the wider space between the two centre cells, however, where the bicycle spokes are situated, the sealing compound should be allowed to run down so as to cover up these spokes. The compound with which the cells are sealed should be carefully chosen not to run down into the cells themselves at 100°F, and not to be so brittle as to crack and provide a way for acid to the bottom of the battery case at the low temperatures likely to be experienced. (13) PLATE GRIDS. Amplifying the remark re grids contained in (4), the outer periphery of the grid should be substantial enough to prevent this being eaten through and caused to break by overcharging. Further, the design of the grid frame-work should be such as to hold paste in place in the best possible way. It is desired to make it clear that, in making provision for this, in the case of a chassis battery, a certain amount of electrical efficiency must be given over to the more important feature of durability. An important things on the chassis battery is to provide durability against combined vibration and overcharging. The grids should have rounded corners and the positive and negative plates should be provided with pairs of feet, those of the positive grids being out of line with those of the negative. The plates should rest by means of their feet on four ribs in the bottom of the cell case, in such a manner that positive plates rest on one pair 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 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. MADE IN GT BRITAIN Contd. | ||