WERKWIJZE VOOR HET VERVAARDIGEN VAN ELEKTROLYTDICHTE DOORVOEREN EN VERBINDINGEN BIJ EEN ELEKTRISCHE ACCUMU- LATORBATTERIJ.

摘要

1,260,255. Bonding together battery components. ACCUMULATORENFABRIK SONNENSCHEIN G.m.b.H. 15 July, 1970 [17 July, 1969], No. 34380/70. Heading H1B. A leak-proof bond between battery components is made by arranging the components in their relative positions but with a cavity between the surfaces to be bonded and maintaining them in this position whilst injecting a composition of a softened thermoplastic and a foaming agent into the cavity and allowing it to expand to a closed-cell foam and solidify. The thermoplastic may be softened by heating whilst maintaining it under pressure to prevent premature foaming. In a particular embodiment, Fig. 1, a single cell accumulator comprises negative plates D and positive plates B which are joined by strap C to lead terminal 6. Cover 3 is of polypropylene and provides cavities 4 and 5 for thermoplastic material to bond the cover to the base and the terminal to the cover. Mould plate 7, of aluminium, closes the cavities whilst providing holes 81 for injection of the thermoplastic. It is removed after the thermoplastic has foamed and solidified. In Figs. 2 and 3 (not shown) the arrangement is similar but the cover is a different shape. Fig. 4 shows a 2 cell accumulator in which cover 23 has a peripheral cavity 24 for bonding the cover to the base and a flange 30 defining a cavity 27 for bonding the cover to inter-cell connector 29 and inter-cell partition 26. In Fig. 6 (not shown) the arrangement is similar but flange 30 is omitted and the cavity is recessed in the cover. Fig. 5 shows a terminal 32 with a metal cap 34 positioned in a cavity 37 for bonding it to the cover. In Fig. 7 inter-cell connector 40 is bonded to partition 42 by thermoplastic material injected into a cavity defined by mould pieces 43 and 431 and plate straps 44. In Fig. 8 the cavity is defined by insulating plate 521 inserted between the plates and connecting straps 48 and mould piece 52. In Fig. 9 terminal 55, comprising brass element 58 and lead coating 56 is bonded to side wall 64 by thermoplastic material injected into a cavity defined by insulating plate 60 and mould pieces 62 and 621.