Патент USA US2107937код для вставки
2,107,937 Patented Feb. 8, i938 UNITED STATES‘ PATENT OFFICE ’ ‘ 2,107,937 METHOD OF MAKING STORAGE BATTERY ' PLATES Clarence A. Hall, Philadelphia, Pa., assignor to' The Electric Storage Battery Company, Phila delphia, .Pa., a corporation of New Jersey No Drawing. Application May 29, 1935, Serial No. 24,082 2 Claims. (01. 136-27) It has been proposed in the past to mix with stiffens the paste, the production of sandy glass the active material or material to become active particles is avoided, and the glass ?bers of small of a storage battery plate ?brous materials of but substantial length are uniformly incorporated and the surface of the plate after the completion various kinds for the purpose of holding the ma 6 terial together and in order to avoid scaling or of the pasting operation is practically as smooth disintegration thereof in service. Glass wool has as that of a plate containing no glass wool. Based on the above discoveries the invention, been suggested but attempts to use it have been unsuccessful. I have found that in attempting generally stated, consists of a storage battery to mix ordinary commercial glass wool of 25 to 30 plate of the lead acid type having a smooth sur microns diameter, it broke up into very short face ?nish and substantially devoid of glass dust 10 or sand, and comprising a grid and a paste sub , lengths. The lengths were too short in propor tion to the diameter to function properly as a stantially ?lling the pockets of the grid and con binding agent. Fibers of greater lengths could sisting of a uniform mixture of active material not be properly applied to the grid because the - or material to become active and of a small per 15 glass ?bers projected beyond the surface of the centage by weight of glass ?bers of the order of 15 plate and in some cases overlapped the bars of 4 to 6 microns in diameter and of a length com the grid, making it impossible to provide a smooth mensurate with the dimensions of the pockets in the grid. ?nish. Furthermore, the projecting ?bers in The invention also consists in introducing glass ?icted injury to the hands of workmen. On ac ?bers into the active material or material to be 20 count of the large diameter of the glass ?bers, 20 come active by primarily making a water paste of they displaced more active material than was de sirable. Hitherto the glass wool was cut into lead oxides of soupy consistency, mixing with said paste glass ?bers in long lengths many times short lengths commensurate with the space be tween the bars of the grid, and these short lengths the dimensions of the pockets of the grid and, 25 were mixed with the lead oxides in a dry state. while the ?bers are water wet, adding to the paste The result was that the glass was broken up into a solution of sulphuric acid and water, which small particles of sandy structure, thereby losing stiiiens the paste, and, by stirring, uniformly dis tributing the ?bers and breaking them up, with its binding e?ect. Objects of the present invention are to avoid out substantial formation of sandy particles, into 30 the above-mentioned defects and disadvantages lengths suitable for pasting the grids. The invention also comprises the improvements and to bind the active material together with glass ?ber in such a way that the plates shall present to be presently described and ?nally claimed. A plate embodying features of the invention smooth surfaces and shall be devoid of sandy particles of glass and shall be satisfactorily bound looks like a standard plate. It has a smooth ?nish and can be handled like an ordinary plate LI 35 by uniformly distributed ?bers, displacing a lim because it is devoid of needle-like projecting ited quantity of active material. In explanation of the difference between the ?bers. It can be pasted without pulling off paste so-called glass silk which I employ in carrying because the ?bers are reduced to vproper length in out this invention and the commercial glass wool the described mixing operation. The ?bers are 40 heretofore unsuccessfully tried, it may be stated well distributed throughout the paste in the pock that the minimum diameter of the glass wool ets of the grid. The capacity of the plate is not ?bers is many times the maximum diameter of reduced but rather is increased as are also du rability and cohesion. More important than all, the glass silk ?bers. This invention is based on the .discovery that, the active material is not dislodged in service. 45 by using glass wool of the order of from 5 to 6 The improvement is particularly marked in the microns in diameter and by introducing it in long initial formation of the plates, where in the case of previous attempts to use glass ?bers scal lengths, illustratively measured infeet, it is possi ble to uniformly distribute ?bers of which the ing occurred, whereas in the case of this invention ratio of length to diameter is increased in the no scaling occurred under the same conditions order of many times that formerly obtainable. The invention is based on the furtherdiscovery of forming schedule. of lead oxides, whereby the fibers are wet with In the practice of the invention use is made of glass wool ?ber of the order of from 5 to 6 mi crons in diameter and of considerable length even measurable in feet. Such glass ?bers are 55 water, and then adding sulphuric acid which introduced in their full length into a primarily that, by introducing such long lengths of small - diameter glass ?bers into a soupy water mixture 50 2,107,937 made mixture or paste or lead oxide material and water, oi’ soupy consistency, by mixing the ?bers into this paste. The ?bers become wet with water and partly separated. There is then in troduced into the paste containing the ?bers‘ a solution of sulphuric acid in water, for example a speci?c gravity 01' approximately 1.400. The effect 01' this is to sti?en the paste into a dough like consistency. The acid is added while the 10 mixture is being stirred and the subsequent stir ring and gradual sti?ening in a few minutes breaks up the long ?bers of glass into lengths suitable for pasting the grids and practically no sandy material is produced from the ?bers. An 16 example of the length into which the ?bers are broken by this operation is an eighth ($6) of an inch more or less. The proportion of glass ?bers to lead oxide material is subject to some varia tion, but I have had good results by using 1% 20 by weight oi’ glass ?bers. The length of the glass ?bers in the ?nal prod uct is determined by the time oi! mixing after the sulphuric acid has been added to the paste. The longer this mixing is continued, the shorter will be the ?bers; The control of this mixing time is therefore an important feature of the process. It will be obvious to those skilled in the art to which the invention relates that modi?cations 30 may be made in details of construction and ar rangement in matters of mere form without de parting from the spirit of the invention which is not limited in respect to such matters or other wise than as the prior art and the appended claims may require. _ - I claim:- . ‘ 1. In the method of introducing glass ?bers into the lead oxide material 01' storage battery plates the improvement which consists in pri marily making a water paste of lead oxide of soupy consistency, mixing with said paste glass wool ?bers of comparatively long lengths by stir ring and while the ?bers are water wet and while the paste is being stirred adding gradually to the pastev a solution of sulphuric acid and water which sti?'ens the paste, and continuing the stir ring to break up the long ?bers without substan 15 tial formation oi’ ?ne particles oi’ glass into lengths suitable for pasting the grids. 2. In the method of introducing glass ?bers into thelead oxide material of storage battery plates the improvement which consists in pri 20 marily making a water paste of lead oxide of soupy consistency, mixing with said paste glass wool ?bers or comparatively long lengths by stirring and while the ?bers are water wet and while the pastels being stirred adding gradually 25 to the paste a solution of sulphuric .acid and water which sti?’ens the paste, and continuing the stirring for a su?lcient time to break up the long ?bers to any shorter lengths that may be so desired. . CLARENCE A. HALL.