RU2224345C2 - Method for unifying external operating conditions for storage battery cycling and charging process during battery flow-line production - Google Patents

Abstract

FIELD: electrical engineering; production of pasted-plate lead-acid storage batteries. SUBSTANCE: novelty is that proposed method involves cooling liquid supply by gravity concurrently in each bath in recirculating cycle through set of pipelines from common delivery tank followed by residue drain into storage tank by way of level spillover, its pumping to heat-transfer apparatus, and post-cooling accumulation in delivery tank; gas and aerosol fractions produced in the course of treatment are discharged at same speed from buffer process space of each bath separately by way of ventilated gas exchange. All plates are treated under identical conditions, therefore technical characteristics of each lot of batteries are similar and comply with Standard Specifications. EFFECT: enhanced quality of storage batteries. 1 cl, 1 dwg

Description

 The invention relates to the electrical industry, namely to the production of lead-acid batteries with pasted electrode plates.

 In the in-line production of the same type of rechargeable batteries, if a large number of products are simultaneously processed on production lines, the problem of unifying the parameters of the acting factors arises, be it temperature, partial pressure of gases or concentration of aerosols. In other words, all batteries processed at each technological site must be in the same physical conditions, which serves as a guarantee of compliance of their final parameters with technical requirements. The identity of the processing conditions turns into a standard technical specifications.

 When in-line battery formation of electrode plates, they are already installed in batteries at their working positions. At the stage of preparation for the formation, all rechargeable batteries, brought to a complete set, are poured with a forming fluid - a solution of sulfuric acid (electrolyte). The formation of plates occurs by dosed electrical exposure. Energy is supplied from an external current source. The processing process due to technological difficulties is divided into several stages, while the current load on the part changes many times, respectively, with the process flow diagram, but all stages (except for pauses) are accompanied by heat generation of different intensities.

 Since the main heat sink is electrolyte, its temperature gradually rises. This affects the speed and direction of the main chemical transformations in the active layer of electrodes. And above all, on the electrochemical reduction of spongy lead (on negative plates) and on the anodic oxidation of lead (on positive electrodes). The physical properties of the forming liquid itself also change.

Studies have shown that in order to optimize such important indicators as the viscosity of the electrolyte, which affects the depth of impregnation of the active layer of the plates, and the dissolution rate of the expanders, it is necessary that the temperature of the electrolyte during processing does not rise above 60 ^o C. You can keep the temperature in the range below this limit only by external cooling of the battery case. When cooled by air, in order to avoid overheating, the forming current is forced to be limited. Water cooling, as much more efficient, makes it possible to carry out processing with high currents. The effect of using the heat capacity of water is increased by organizing forced cyclic water exchange. This simple and easily manageable method of reducing and stabilizing the temperature of the electrolyte is widespread in enterprises. Examples of the use of cooling of this type are known.

 The closest technical solution, taken as a prototype, is a method of battery formation with water cooling of lead-acid batteries according to US patent 4604564, IPC H 02 J 7/00, H 01 M 10/50.

 It consists in the fact that the batteries selected for processing are divided into groups and each of them is placed in tanks filled with water. The water exchange is arranged in such a way that the tanks are located at different levels (one above the other) and are connected by pipelines so that the water from the main, filling the upper tank to the set level, overflows to the one located directly below it, and from there to all the next ones in height. Water is continuously supplied to the upper reservoir, therefore, its circulation through all vessels of a given heat exchanger does not stop until the formation is completed. Each battery is connected to an appropriate charger.

 The disadvantages of the considered method of forming batteries include the following.

 1. Since the tanks are connected in series, the coolant in them has a different temperature, since the same volume of water passes through all the tanks in turn, heating in each. In this case, the operating temperature of the lowermost tank differs significantly from the temperature of the upper. Formation under different temperature conditions gives a significant final discrepancy in the technical characteristics of the finished products.

 2. The technological volumes above the tanks are not isolated from the atmosphere of the workshop, which not only worsens the working conditions of the personnel, but can also cause temperature fluctuations in the tanks themselves.

 The proposed solution is based on the task of increasing the output of high-quality rechargeable batteries with normative technical characteristics after their formation and charging by the in-line method due to the unification of operating parameters.

 The problem is solved in that in the proposed method, the cooling fluid is fed by gravity in parallel to each bath in a reverse cycle through a system of pipelines from a common pressure tank with subsequent discharge of excess by the method of level overflow into a storage tank, pumped into a heat exchanger and collected in a pressure tank after cooling, and gas and aerosol fractions that are formed during processing are discharged at the same rate from the buffer technological volume of each bath separately by ventilation gas exchange.

 The inadmissibility of violation of the temperature regime of product formation forces one to turn to the water cooling method, as the most effective, which allows precise temperature control and prompt correction of the intensity of its circulation. It is also necessary to monitor the course of parallel processes that can disrupt the regime (for example, the intensity of the release of oxygen and hydrogen and the speed of their pumping beyond the boundaries of the process volume).

 The proposed method makes it possible to reliably equalize the physical conditions in all the working volumes of the formation site and stabilize them within the technological requirements.

 This is achieved, firstly, due to the fact that the coolant enters all bathtubs in parallel, and not sequentially, as in the prototype, from a common source (pressure tank) and has the same initial temperature. The reverse cycle of water supply using a common tower-type heat exchanger (cooling towers) makes it possible to establish and maintain unchanged temperature conditions in all bathtubs at the same time. Since the strength of the forming currents is different at different stages of processing, it is accordingly possible to change the rate of circulation of water in the bathtubs, which leads to operational stabilization of the temperature of the electrolyte in the batteries. And, secondly, due to the maximum compensation of the influence of random factors from the external environment on process volumes by controlling the intensity of the removal of gases, steam and aerosols, which makes it possible to stabilize the partial pressure and composition of the atmosphere above the surface of the coolant.

 According to the information available to the authors, the proposed significant differences that characterize the essence of the invention are not known in this section of the technology.

 The proposed technical solution can be used at enterprises for the production of rechargeable batteries with pasted electrodes, in particular, lead-acid types.

 The criterion of "industrial implementation" is confirmed by the relevance of the method and its practical binding to real production technologies.

 To prove the feasibility of the proposed method, we consider one of the options for its implementation on a specific structural basis.

 The drawing shows a diagram of a possible layout of the nodes of the in-line formation and battery charging section.

 The diagram shows the minimum number of nodes whose coordinated operation is able to provide processing in full accordance with the program, as well as thermodynamic support of the process. All non-essential details are omitted, the electrical circuitry for connecting the batteries with energy converters, as well as operational information collection and control systems.

As already emphasized, the cooling system operates on a reverse cycle, that is, it is once filled with water, and then disconnected from the sewage and water supply lines. The objects of thermal stabilization are batteries 1 located in bathtubs 2. The heat agent is water 3, which fills the bathtubs to the level of drain hole 4 (not less than 3/4 of the height of the battery). Excessive thermal energy, which is released on the electrode plates during formation, is absorbed by water washing the battery case. To organize the removal of this energy, the water in the baths is exchanged continuously. Chilled water (T ₀ ) comes from the pressure vessel 5 by regulated gravity flow. To maintain the identity of the physical conditions, the level difference between tank 5 and all bathtubs is the same.

In addition, water is supplied to the baths in parallel. Removal of excess water occurs by overflow through constantly open drain holes 4 located at the same height from the bottom. The cooling rate is controlled by the water exchange rate, achieving a constant electrolyte temperature (T _p ). The water that has merged from all the bathtubs is collected in a common tank 6 (storage tank), followed by pumping it 7 into the heat exchanger 8.

 The heat balance of a closed system is restored by cooling the waste water in the heat exchanger (cooling towers), where its temperature decreases due to both intensive evaporation and direct heat exchange with air. Chilled water accumulates in the pressure vessel 5, from where it again spreads evenly through the baths 2. During the many-hour formation process, water circulates in the system according to the described scheme. After the formation and charging of the batteries are completed, the bathtubs are completely drained by draining the water into the drive, and the products are replaced with their new batch. For the next start of the cooling system, the bathtubs are again filled and circulation is restored.

 Above each bathtub, intake umbrellas 9 of the forced gas exchange system are mounted, which are connected via air ducts 10 to the filter ventilation device 13. In order to stabilize the external conditions, the buffer technological volumes 11 above the bathtubs are separated from the workshop’s atmosphere by retractable curtains 12. The compression created by the ventilation unit is distributed evenly, which makes it possible to equalize the rate of removal of substances and gases from volumes 11 and thus prevent the occurrence of temperature fluctuations in the bathtubs. In addition to the purely technical effect, the curtains protect the workshop atmosphere from substances harmful to the health of the operating staff. Naturally, monitoring at such a critical site for the manufacture of batteries is organized using modern information technologies.

 All design features of this unit serve the achievement of one goal - ensuring the identity of thermal conditions in all bathtubs without exception.

 The claimed technical solution makes it possible to increase the output of high-quality products with the same technical characteristics in the in-line production of batteries by unifying the external operating parameters of the process of their formation and charging.

Claims (1)

The method of unification of external operating parameters of the process of formation and charging of batteries during their continuous production, which consists in the fact that the batteries are poured with electrolyte, collected in groups, installed in bathtubs filled with cooling liquid, and after settling, they are formed, characterized in that the cooling the liquid is fed by gravity in parallel into each bath in a reverse cycle through a piping system from the total pressure tank with subsequent discharge of excess by the method of level overflow in the accumulator nuyu capacity pumping to the heat exchanger and collected in the pressure container after cooling, and gas and particulate fractions which are formed during processing, is removed at the same rate from the buffer process volume each vat separately by gas exchange vent.