RU2076403C1 - Method of reconditioning of lead acid storage batteries - Google Patents

Abstract

FIELD: production of lead acid storage cells and batteries. SUBSTANCE: defective positive plates and sludge are ground to power and mixed with electrolyte, ratio 1:0.13 by mass. Sponge lead is removed from negative plate grids with degree of sulfation exceeding 20%. Paste is applied to cleaned grids and is pressed down at a pressure of 20-30 atm, then dried at temperature within 30 and 100 C for 24 hours. Positive plates are formed into half-elements, then negative half elements are formed, half elements are assembled into full element, which is placed in can, into which distilled water is poured and then direct current of 0.03-0.05 A is passed through element. EFFECT: reduced consumption of lead. 4 cl, 6 dwg

Description

 The invention relates to electrical engineering, and in particular to a method for the recovery of lead-acid batteries.

 In a battery, as in a galvanic cell, electric current is a consequence of chemical processes. Unlike a battery in a galvanic cell, the resulting chemical compounds cannot be decomposed a second time and brought to their original state by current from a constant source, since electrodes and solution are consumed during operation. Chemical processes in galvanic cells are irreversible. Therefore, galvanic cells are called primary.

 Widely known current sources operating on the principle of reversibility of chemical processes. These current sources are batteries.

 During battery charge on the electrodes and in the electrolyte (figa, 5B) are formed those substances that were before the complete discharge.

 Chemical reactions that occur in the battery during discharge and charge can be represented in the following form (see the end of the text).

In addition, it has been theoretically established and proved by practice that lead dioxide PbO ₂ and sponge lead Pb are highly chemical resistant in sulfuric acid electrolyte H ₂ SO ₄ . The amount of active substance PbO ₂ on the positive plates and Pb on the negative plates is much larger than theoretically necessary to obtain a certain battery capacity. This ratio is characterized by the utilization of the active substance. In a lead-acid battery, this coefficient does not exceed 0.4. Therefore, during the operation of the battery, only 40% of the active substance enters into a chemical reaction with the electrolyte, the remaining 60% do not interact and their chemical composition does not change.

 These 40% of the reacted active substance during the electrochemical reaction partially or completely precipitates, which is subject to reduction.

 A known method for the recovery of lead-acid batteries (A.E. Severny et al. Use, repair and storage of batteries, M. GOSNITI, 1991, p. 94), in which the spent battery is divided into negative and positive half blocks, consisting of positive and negative plates, respectively. Replace the failed plates, and then assemble the battery and charge it.

 In this method, new plates supplied by factories are used for repairs, that is, expensive lead plates have to be purchased. All spent lead sludge is discarded, i.e. Do not dispose of, thereby polluting the environment, worsening the environment.

 Closest to the claimed is a method for the recovery of lead-acid batteries, which consists in the fact that the spent battery is divided into negative and positive half blocks, consisting of negative and positive plates, respectively, crushed destroyed positive plates, mix the resulting powder with an electrolyte to obtain a paste, apply the paste to the grids, press, dry, then restore and reassemble the battery and charge it (ed, sv, USSR N 112833).

 In order to increase the battery life for the manufacture of paste, an active mass of positive plates in pure form without sludge, without mass of negative plates and extraneous binders is used. After pressing, the plates are re-coated and pressed again.

 Before disassembling, the spent battery is pre-charged for 4 to 5 hours, the negative plates are pressed with tarpaulin gaskets and after assembly with the positive plates, the battery is charged.

 In auth. St. N 112833 indicates that the active mass of positive plates is used in its pure form without sludge, without mass of negative plates and without extraneous binders. It should be noted that during the operation of the battery, sulfation of the plates occurs, the mass of positive and negative plates precipitates. In this case, there is no electrochemical destruction of all constituent components. Therefore, it is impossible to use a lot of positive plates in their pure form.

 After disassembling the active mass blocks, there are still no positive electrodes. The mass obtained after disassembly should be converted into the active mass only by formation. Formation is the process of formation of electrochemical active masses.

 The results of the experiments show that the increase in battery life does not occur when using double pressing. The service life depends only on the pressing force.

 In addition, recharging can be done with a working battery. For recovery, faulty rechargeable batteries are used, which have a short circuit, crumbled mass, punched covers, damaged interconnects. Recharging such batteries will have no effect.

 The basis of the present invention is the task of creating a method for the recovery of lead-acid batteries, in which the restoration of positive and negative plates that make up the half-blocks of the battery from the exhausted positive and negative plates depreciation, allows you to restore the battery without the use and purchase of expensive lead.

The problem is solved in that in the method for the recovery of lead-acid batteries, which consists in the fact that the spent battery is divided into negative and positive half blocks, consisting of negative and positive plates, respectively, crushed destroyed positive plates, mix the resulting powder with an electrolyte to obtain pastes, apply the paste to the grids, press and dry, then restore and reassemble the battery and charge it according to acquiring, simultaneously with grinding the mass of the destroyed positive plates, the spent battery is crushed to obtain particles from 0.02 to 0.04 μm in size, and the resulting powder is mixed with the electrolyte at a ratio of 1: 0.13 weight. h, spongy lead is removed from the gratings of the negative plates, the degree of sulfation of which is more than 20% after applying the paste to the gratings, they are pressed at a pressure of 20 to 30 atm, and drying is carried out at a temperature of 30 to 100 ^o C for 24 hours, the positive the plates are formed into half blocks, then the negative half blocks are formed from negative plates, the degree of sulfation of which is less than 20% of the positive and negative half blocks obtained, the battery packs are collected, which before charging They put it in a case with distilled water and pass a constant electric current of 0.03 - 0.05 A from the capacity of the rechargeable battery to form lead dioxide on the positive plates, and sponge lead in negative form on the negative plates, after which they are charged.

 It is advisable that the applied lattice of positive and negative plates be used for applying the paste.

 It is advisable that the spongy lead removed from the gratings of the negative plates is dried, crushed, mixed with an electrolyte in a ratio of 1: 0.13 weight. hours and applied to the released lattice of negative plates, from the obtained negative plates formed negative half blocks.

 It is useful that a mixture of sulfuric acid with distilled water in a ratio of 1: 3 with a density of 1.27 g / cm3 be used as the electrolyte.

 The reversibility of chemical reactions, the chemical stability of lead in an electrolyte of sulfuric acid, only 40% of the active substance interacting with the electrolyte, and the absence of electrochemical destruction of the active substance make it possible to restore accumulator batteries that have passed the amortization period.

 In addition, all the lead deposits of the former USSR are located in Kazakhstan, and a constant increase in railway tariffs leads to a sharp increase in the cost of new lead-acid batteries.

 In FIG. 1 shows a General view of the battery with an integral cover (partial tear); figure 2 General view of the battery pack, consisting of negative and positive half blocks; figure 3 General view of the battery with removable covers (partial tear); figure 4 is a General view of the battery unit; figure 5, the diagram of the electrolyte cell in the process of starting the charge of the positive and negative plates; figure 6, is a diagram of the electrolyte cell at the end of the charge of the positive and negative plates, which turned into positive and negative electrodes.

 The recovery method of lead-acid batteries is as follows.

 To restore one battery (figure 1), as a rule, are used 2 3 past the depreciation period of the battery. The claimed method allows the use of lead parts of disposable batteries, which are not subject to repair and restoration.

 The spent battery is divided into negative 1 (figure 2) and positive 2 half blocks. To do this, in the case of restoration of the battery with removable covers 3 (Fig. 3), the interelement connections 4 are drilled on the drilling machine. The inter-element connections 4 are removed and stacked in boxes for reuse, unsuitable are sent for re-melting, and in case of restoration of the battery (Fig. 1) with one-piece cover 5, this cover 5 is cut out.

 Negative 1 (Fig. 2) and positive 2 half blocks consist of a set of negative plates 6 (FIG. 2) and positive plates 7. The plates 6 and 7 in the half blocks are interconnected by means of bridges 8 and 9.

 Carefully drain the electrolyte from the battery housing.

The positive plates 7 of the half block 2, as a rule, are completely destroyed. Therefore, the collection is carried out from the bottom of the sediment body, which is the particles of the positive plates 7. This sediment and the remaining undamaged parts of the positive plates 7 are first placed in an oven (not shown in FIG. 2) and dried at a temperature of 250 300 ^o C. Then the dried positive plate 7 and the precipitate is ground into a powder with a particle size in the range of 0.02 0.04 microns. The grinding is carried out by any known grinding device, for example in a ball mill.

 The resulting powder is mixed with an electrolyte in a ratio of 1: 0.13 weight. hours to obtain a paste.

 Then they start processing the negative plates 6. In the used battery, the negative plate 6 is a grate 10, in the cells of which there is partially or fully sulfated sponge lead 11. If the degree of sulfation of sponge lead 10 is more than 20%, it is removed from the grate 10. This grate 10 washed and used as a collector for the positive plate 7.

The resulting paste is applied to each free grate 10 and pressed on a press (not shown in FIG. 2). The pressing pressure is 20 30 atm. After that, the positive plate is dried at a temperature of 30 to 100 ^o C for 24 hours. The resulting positive plates are collected in positive half blocks 2. Assembly is carried out in a known manner.

Then form negative half blocks 1 from the negative plates 6, the degree of sulfation of which is less than 20%
From the obtained negative 1 and positive 2 half blocks, blocks 12 are assembled (Fig. 4), while separators 13 (Fig. 1) of miplastic and mipor insulating material are placed between all positive and negative plates 5, 6.

 Blocks 12 are placed in the housing 14 (Fig. 5) with distilled water 15, are electrically connected to each other and a constant electric current of 0.03 0.05 A is passed. As a result of the electrochemical process in positive plates 7 (Figs. 5, 6), lead dioxide, and in negative plates 6, spongy lead goes into active form.

 It is possible that the separated spongy lead from the negative plate is dried, ground to a particle size of 0.02 0.04 μm, mixed with an electrolyte.

As the electrolyte, a mixture of sulfuric acid with distilled water in a ratio of 1: 3 is used, which ensures an electrolyte density of 1.27 t / cm ³ .

Claims (4)

1. The method of recovery of lead-acid batteries, which consists in the fact that the spent battery is divided into negative and positive half-blocks, consisting of negative and positive plates, respectively, crushed destroyed positive plates, mix the resulting powder with an electrolyte to obtain a paste, paste on gratings, pressed and dried, after which they are restored and the battery is assembled and charged, characterized in that at the same time as grinding the mass of the destroyed positive plates grind the sediment of the spent battery to obtain particles of 0.02 0.04 microns in size, and the resulting powder is mixed with the electrolyte at a ratio of 1: 0.13 wt.h. spongy lead is removed from the gratings of negative plates, the degree of sulfation of which is more than 20% after applying the paste to the gratings, they are pressed at a pressure of 20 30 atm, and drying is carried out at a temperature of 30 100 ^o C for 24 hours, the resulting positive plates are formed into half blocks, then form negative half blocks from negative plates, the degree of sulfation of which is less than 20% of the positive and negative half blocks obtained, collect the battery blocks, which are placed in the housing before charging distilled water and passed a constant electric current of 0.03 - 0.05 A for the formation of the positive plates to lead dioxide and the negative plates of spongy lead active form, followed by charging.  2. The method according to p. 1, characterized in that for applying the paste use the released lattice of positive and negative plates.  3. The method according to p. 1, characterized in that the dried sponge lead, removed from the gratings of the negative plates, is crushed, mixed with an electrolyte in a ratio of 1: 0.13 wt.h. and applied to the released lattice of negative plates, from the obtained negative plates form negative half blocks. 4. The method according to PP. 1 3, characterized in that the electrolyte is a mixture of sulfuric acid with distilled water in a ratio of 1: 3 with a density of 1.27 g • cm ³ .

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