GB555047A - Improvements in dry cell and battery and method of making the same - Google Patents

Abstract

555,047. Galvanic batteries. BURGESS BATTERY CO. May 8, 1942, No. 6261. Convention date, April 30, 1941. [Class 53] A dry cell includes a metal can open at one or both ends and containing the active mass, the end or ends of the can being closed by a body consisting wholly of sealing material which forms one wall of an empty expansion chamber at the end or ends of the cell. The sealing material is not supported by a washer, thus reducing cost and avoiding short-circuiting owing to saturation of the washer by electrolyte. The seal is effected by lowering the open end of the can into the fluid sealing material. As shown a battery is formed of cells in an outer container composed of two tray-like members 2, 3, which may be of paraffin-impregnated cardboard. The cells are formed of open-ended metal cans containing the active materials which fill them except for spaces 11, 12 at the ends which form expansion chambers for the evolved gases. They are covered with insulating jackets formed of a preferably somewhat elastic material, suitable materials being that known under the Registered Trade Mark " Pliofilm," a rubber hydrohalide, rubber, ethyl cellulose, " Parafilm," and polystyrene. In making the battery, the cells are assembled in a suitable form, for which purpose the tray 2 may be used, the inter-cell connections are made, and the whole block is inverted and lowered as shown in Fig. 3 into the tray 3, which contains a shallow body of fluid sealing material 7. This is forced up around, and into the ends of the cells, which are thus sealed, the air pressure preventing the material from filling the spaces 12. After the sealing material has cooled the form or the tray 2 is removed and the block of cells is inverted and lowered into fluid sealing material in a tray 2, so that the other ends of the cells are similarly sealed. Alternatively, the fluid sealing material may be contained in thin paper liners supported by suitable forms, the paper either being removed before placing the battery in an outer covering, or retained; or, the individual cells may be assembled by inserting them individually in a tray which is to form part of the permanent covering and contains sealing material maintained in a fluid condition until all the cells are in position. In another form, the tops of the cells are sealed by pouring the sealing material directly on to the top of the active material, gas spaces being provided only at the bottom by sealing the lower ends as above described. The insulating jackets may extend beyond the ends of the cans, so that the gas spaces are formed within the jacket extensions, and if elastic jacket material and plastic sealing material be employed the gases will, under excess pressure, escape into spaces formed between the metal can and the jacket by stretching the latter. Specification 531,379 is referred to.