PROCEDURE AND MEANS FOR MANUFACTURING STORAGE BATTERY PLATE ASSEMBLIES

Abstract: The present invention concerns a procedure and a means for manufactur­ ing plate assemblies for a bipolar or semibipolar storage battery containing bipolar and monopolar plates which contain positive and/or negative active mass. The means (100) comprises forming apparatus disposed to form on an electrically insulating support material (27) a plate frame web (25) containing longitudinally continuous and transver­ sally spaced plate frame blanks containing electrically conductive material, adding apparatus (35,36) disposed to add onto the plate frame web (25) containing plate frame blanks longitudinally continuous and transversally spaced zones constituted alternatingly by positive and negative active mass (20,21), and cutting apparatus disposed to cut by transversal and longitudinal cuts (A,B), from the plate frame web (25) containing active mass zones, plate assembly blanks containing bipolar and/or monopolar plates.

Description: The invention relates to a procedure for manufacturing storage battery plate assemblies according to the features indicated in the preamble of claim 1. The invention starts out from a prior art as it is known from US-PS 4 192 049. This document shows a method for manufacturing battery plates, which works as follows: In a nonconductive web transversally spaced plate frame blanks are arranged by weaving conductive material wires into the web. Zones constituted by transversally alternating positive and negative active mass, are added to this plate frame web. After a transversal cut has been made all over the web, an internally unconnected storage battery can be achieved by folding the plates against one another. To fold the plates and to connect them internally after the folding seems very difficult to be effected. The object of the invention is to provide a procedure for manufacturing storage battery plate assemblies according to the preamble of claim 1 which can completely be assembled in an effective way. According to the invention this object is solved by the features of claim 1. Thus, by properly adding the active mass in combination with useful longitudinal and transversal cuts, the step of internally connecting the plates after having assembled them becomes unnecessary, because the plates are already connected by assembling them, respectively by stacking them. In "Patent Abstracts of Japan", Vol. 7, No. 62 (E-164)1207 (JP-A-54-208071) it is shown how a web is enriched with a lead alloy poured in molten state from a trough on a roller to produce a combined web/lead-alloy structure. The DE 31 24 703 A1 discloses a method for manufacturing webs in form of bands and combining them with ciment conductors in order to produce grids on which active mass can be deposited. The invention is advantageously developed by the measures mentioned in the subclaims. The invention is described in detail with reference to certain advantageous embodiments illustrated in the accompanying figures, to which the invention is not intended to be exclusively confined. Fig. 1 is a cross-sectional view of a storage battery, the plate assemblies of which have been produced in accordance with the present invention. Fig. 2 is a sectional view long the line II-II in Fig. 1. Fig. 3a is a top view of an advantageous embodiment of a negative monopolar plate frame used in the storage battery of Fig. 1. Fig. 3b is a top view of an advantageous embodiment of the bipolar plate frame used in the storage battery of Fig. 1. Fig. 3c is a top view of an advantageous embodiment of the positive monopolar plate frame used in the storage battery of. Fig. 1. Fig. 4 is a schematic axonometric projection of an advantageous embodiment of the means for producing the storage battery plate assemblies. Fig. 5 is a schematic elevational view of an advantageous embodiment of the means for producing a plate frame web on a support material web. Fig. 6 is a schematic elevational view of another advantageous embodiment of the means for producing a plate frame web on a support material web. Fig. 7 is a top view, partially schematically, of a plate frame web and a manner in which the plate frame parts required for manufacturing a storage battery can be cut from the plate frame web. Fig. 8 is a schematic cross-sectional view illustrating the stacking of completed plate frames. Fig. 9 is a top view, partially schematic, of a second plate frame web and the manner in which the required plate frame parts for producing a storage battery can be cut from said plate frame web. Fig. 10 is a schematic cross-sectional view of another mode of stacking completed plate frames cut from the plate frame web of Fig. 9. In the embodiment shown in Figs 1 and 2, a 6 volt storage battery is generally indicated by reference numeral 10. The storage battery 10 comprises one or several cells enclosed in a case 11. Each cell contains electrolyte, monopolar plates 12 and bipolar plates 13 coated with positive and/or negative active mass and separated by separator plates 14. Furthermore, the storage battery 10 contains the requisite electrically conductive connectors which connect plates 12,13 and/or cells together. The wall separating each cell from adjacent cells or from the case 11, or sealing it off, is produced by filling the spaces surrounding the plate stacks located in the case 11 and the spaces therebetween with an electrically insulating substance 19 impermeable to electrolyte and which has been cured directly in place to establish tightly sealing and/or insulating walls. In Figs 1 and 2, lugs connecting plates with the same polarity are indicated with reference numerals 15a and 15b. The positive terminal of the storage battery is indicated with reference numeral 16a and the negative terminal with reference numeral 16b. Reference numeral 18 indicates an injection aperture through which the electrically insulating substance impermeable to the electrolyte is inserted into the casing 11. Reference numeral 17 indicates an acid supplying aperture, through which the storage battery 10 is filled with acid in a manner known in prior art, in order to obtain a storage battery ready for use. As shown in Fig 3a, the monopolar plate frame 12 is provided with negative active mass 21, which the bipolar plate frame 13 in Fig. 3b is provided with positive active mass 20 and negative active mass 21, and the intervening portion 22 is uncoated. As seen in Fig. 3c, the monopolar plate frame 12 is provided with positive active mass 20. The electrically conductive bipolar plate or bipolar plate grid 13 is composed of a reticular structure containing electrically conductive material, one end 20 thereof being coated with Positive and the other end 21 with negative active mass, while the intervening part 22 remains uncoated. This type of reticular structure is constituted by a supporting structure which does not conduct electricity and to which electrically conductive wires or an electrically conductive reticular structure have been joined. In an advantageous embodiment of the invention, the storage battery of Fig. 1 comprises monopolar and bipolar plates 12,13, stacked upon each other and also separator plates 14 interposed there between, so that in the outer cells every second plate is monopolar, 12, and every second plate is an end with opposite polarity of a bipolar plate 13. The intermediate cells contain ends with opposite polarity of bipolar plates 13 in alternation. At the points between cells the uncoated portions-22 of the bipolar plates 13 are in register and constitute the electric leads 34 passing through the insulating and/or sealing partition that has been formed upon curing of the electrically insulating and electrolyte-impermeable substance 19. In the embodiment according to Fig. 4, the means for manufacturing storage battery plate assemblies has been generally indicated with reference numeral 100. The means 100 comprises, in this illustrated embodiment, a continuous-action casting drum 23 to which molten lead is fed from a feeding funnel 24, and a support net roll 26 for feeding a support net web 27 under the plate frame web 25 that has been cast in addition to a hot-roll 28 for joining the cast plate frame web 25 to the support net web 27 by hot rolling. Adding means 35 and 36 for adding negative or positive active mass on top of the plate frame/support net web 31, and cutting means 37 and 38 for cutting the plate frame parts required in the manufacturing of the storage battery are also provided. Fig. 4 schematically presents the stacking of monopolar and bipolar plates together with separator plates 14 to form a blank for a 6 V storage battery. In the embodiment according to Fig. 5, molten lead is fed onto the continuous-action casting drum 23 from the feeding funnel 24. When the casting drum 23 is rotated in the direction indicated by the arrow, a cast plate frame web 25 is produced. From the support net roll 26 the support net web 27 is fed in under the cast plate frame web 25 as indicated with an arrow. The support net web 27 and the plate frame web 25 deposited thereon, pass through the hot-roll 28. The upper roll of the hot-roll 28 is indicated with reference numeral 29, and the lower roll with reference numeral 30. In Fig. 5, the completed support net/plate frame web is indicated by reference numeral 31. In the embodiment of Fig. 5 the plate frame web 25 produced by continuous casting is thus connected to the support net web 27 by means of hot-rolling. In the embodiment of Fig. 6, the support net web 27 coming from the support net roll 26 in the direction indicated by an arrow, is pressed against the casting drum 23 at a suitable temperature. Reference numeral 32 indicates an auxiliary roll disposed to press the cast plate frame web 25 and the support net web 27 against the casting drum 23. reference numeral 33 indicates an auxiliary roll located lower down, after which the support net/plate frame web 31 travels in the direction indicated by an arrow. In this embodiment, the support net web 27 is above the plate frame web 25. When the procedure of Fig. 6 is applied, it is not necessary to cut any metallic lead in the subsequent cutting phase, since the plate frames 25a may be cast in separate pieces. As shown in Fig. 7, it is possible to manufacture by the procedure of the present invention, modular plate assemblies for a lead storage battery for example in the following manner. Upon a plastic or glass fibre net web 27 used for the supporting structure, plate frames 25a are cast with a continuous-action casting machine. Since the supporting structure 27 takes up any mechanical stresses, the plate frames 25a can be optimized with respect to the electrical properties thereof. When the casting technique shown in Fig. 5 is utilized, there may be a plurality of leads per each plate frame 25a from one cell to another. After the casting, the plastic/lead web 31 is passed to a pasting step in which the positive active masses 20 and the negative active masses 21 are pressed into place upon the plate frames 25a. The web 31 is then cut up into plate assemblies, so that each plate assembly has either a positive or a negative monopolar plate 12 at one end thereof, and the requisite number of bipolar plates 13. In the embodiment according to Fig. 7, the transverse cutting lines are indicated by letter A, while the longitudinal cutting line is indicated by letter B. The leads connecting the plate frames 25a are indicated with reference numeral 34. As shown in Fig. 8, the monopolar plates 12 and bipolar plates 13 are stacked together with separator plates 14 to form the blanks of a storage battery 10a. This type of blank contains at least two layers of plates so that one plate layer ends at one with a negative plate, and the other plate layer at the opposite end in a positive monopolar plate. When a storage battery contains several blanks, these are interconnected in parallel by casting lead jumpers to connect the lugs 15a and 15b of the monopolar plates. Alternatively, the lugs 15a and 15b may be electrically interconnected to the respective lugs of the other blanks in another manner. The blanks are packed in cases 11 for forming the separating partitions 19. Dry-out ripening, acid supply and forming are accomplished by a technique known in and of itself in the art, disclosed for example in Finnish patent application No. 855096. An example of how a 12 volt storage battery 10a is manufactured is presented In the embodiment of Fig. 8. As depicted in Figs 9 and 10, in an advantageous embodiment of the invention, the steps for manufacturing a blank for a 12 volt storage battery 10b are as follows. First, the starting point is a support net web 27 of width twice the length of a completed storage battery 10b. Upon this support net web 27 the plate frames 25a are attached, for instance, by applying the casting technique of Fig. 5. Next, the plate frames 25a are pasted in the following step as shown in Fig. 4. The pasting may be carried out with a pasting machine 35,36 which produces band-like strips of active mass on the appropriate areas of the plate frames 25a. The areas 22 between the active mass strips 20 and 21 remain free of mass. Insulating material 18 is later injected upon these areas 22 to form the cell partitions. The bipolar plates 13 are formed by these pairs of strips, where the plate frames 25a with positive and negative active mass 20, 21 are fused together. The monopolar plates 12 are outermost on the sides. Lugs 15a and 15b are cast on the monopolar plates 12 by which the plates are connected to the terminal posts 16a and 16b subsequent to stacking the storage battery 10b. The web 31 is cut up into plate assemblies in the manner shown by the cutting lines A and B, and the plate assemblies being stacked together with separator plates 14 to become blanks for a storage battery 10b, as depicted in Fig. 10. The separator plates may also be connected to the active mass strips 20,21 , prior to cutting, which considerably simplifies the stacking. The cutting of the web 31 along the lines A and B may be accomplished, e.g., by means of a high velocity water jet. A manufacturing example of a 12 volt semibipolar storage battery is presented in Fig. 10.

Claims: A procedure for manufacturing plate assemblies for a bipolar or semipolar storage battery comprising bipolar and monopolar plates containing positive and/or negative active mass, wherein (a) on an electrically insulating support material (27) is formed a plate frame web (25) containing transversally spaced plate frame blanks containing electrically conductive material, (b) on the plate frame web (25) containing plate frame blanks are added zones constituted by transversally alternating positive and negative active mass, (c) plate blanks containing bipolar and/or monopolar plates are cut with transversal cuts from the plate frame web (25) containing active mass zones, characterized in that: (d) the plate frame web is constituted by longitudinally continuous plate frame blanks, to which are added zones of active mass which are continuous in the longitudinal direction and transversally spaced, longitudinal cut being made so that upon stacking the cut plate units internally connected bipolar plate assemblies and optionally monopolar plate assemblies are constituted. Procedure according to claim 1, characterized in that the electrically conductive plate frame web (25) is produced by casting a lead blank to constitute the plate frames (25a) and wiring connecting the same. Procedure according to claim 2, characterized in that a support net web (27) of a plastic material is formed and the cast plate frame web (25) is joined to the support net web (27) by means of hot-rolling. Procedure according to claim 2, characterized in that a support net web (27) of a plastic material is formed and the cast plate frame web (25) is connected to the support net web (27) by pressing the support net web (27) against a casting drum (23) and the plate frame web (25) which the latter produces. Procedure according to one of the preceding claims, characterized in that the plate frame web (25) containing active mass zones and a web containing separator mass are conducted in superimposed contact to the cutting phase for cutting the storage battery plates and the separator plates in one work phase.

Inventors: BLOMBERG, MATS, LOPONEN, MARKKU
Applicants: NESTE OY
Application year: 1987
Main classification: H01M10
IPC codes: H01M4, H01M10, H01M2