JP2010177168A - Recycling treatment method and device of lead storage battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recycling treatment method in which recycling treatment of a lead storage battery is carried out stably in a short time, and a device. <P>SOLUTION: An aqueous solution containing carboxymethyl cellulose sodium salt is injected into an electrolytic solution 2 in order to carry out a recycling treatment in the lead storage battery 1, in which a positive electrode body 3 carrying lead dioxide and a negative electrode body 4 carrying lead are immersed into the electrolytic solution 2 containing dilute sulfuric acid. A frequency formed by a signal voltage in which trigger signals with different voltage values are combined together, transmits a regenerative current of 5 to 12 kHz from the positive electrode body 3 to the negative electrode body 4, and heats the electrolytic solution 2 to be maintained in a temperature state of 50 to 60°C, and in the case temperature state of the electrolytic solution 2 is elevated to 60 to 70°C, stops supply of the regenerative current. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a regeneration processing method and apparatus for regenerating a lead storage battery having a reduced charge capacity by repeating charging and discharging.

  Secondary batteries that can be repeatedly charged and discharged are used in many fields, but among secondary batteries, lead-acid batteries are widely used for vehicles because they provide stable output and can be manufactured at low cost. ing.

  Lead-acid batteries gradually decrease in charge capacity when used repeatedly for charge and discharge, and when the charge capacity decreases to less than half of the original, they are replaced with new ones as the product life has come to an end. ing.

  What is said to affect the product life of such a lead storage battery is a phenomenon called sulfation that proceeds inside the lead storage battery. In a lead-acid battery, a positive electrode body supporting lead dioxide and a negative electrode body supporting lead are immersed in an electrolytic solution containing dilute sulfuric acid, but a hard crystal of lead sulfate is generated on the surface of the negative electrode body as charging and discharging are repeated. It becomes like this. Such an accumulation phenomenon of lead sulfate on the surface of the negative electrode body is generally referred to as sulfation.

  As the sulfation proceeds, the surface of the negative electrode body is covered by the accumulation of lead sulfate. Since lead sulfate is hardly electrically conductive and has low solubility, lead storage batteries in which sulfation has progressed and the negative electrode body is covered with lead sulfate cannot be fully charged and discharged, and are treated as having expired. It is.

  It has been proposed to recycle and reuse a lead storage battery whose product life has expired. For example, in Patent Document 1, a lead storage battery in which lead sulfate is deposited on the electrode surface is supplied with a DC pulse current of 1 to 8 A at a voltage higher than the charging voltage to reduce the deposited lead sulfate and include carbon colloid particles. A method for regenerating a lead-acid battery using a carbon suspension as an electrolyte and applying a DC voltage is described. Further, in Patent Document 2, a charging period in which a charging current in which a base current and a square wave pulse current with a pulse frequency of 1 to 5 kHz are superimposed is applied for 5 to 10 minutes with a pause period of 0.5 to 1 minute is periodically inserted. The method for regenerating a lead-acid battery is described repeatedly. Further, in Patent Document 3, a charging current that superimposes a floating charging current from a charger, a DC base current from a regenerator, and a square-wave pulse current is supplied to an operating storage battery by a floating charging method, and time series A storage battery regeneration processing method is described in which the progress of the storage battery regeneration process is monitored based on the voltage data of each cell of the storage battery that is collected automatically.

Japanese Patent No. 3510775 Japanese Patent No. 3723895 JP 2007-80552 A

  In the above-mentioned prior art, lead sulfate accumulated by sulfation can be removed by applying a pulse current. However, since the temperature of the electrolyte rises due to heat generated by the pulse current, it is necessary to suppress the temperature rise. For example, as shown in Patent Document 2, an increase in temperature can be suppressed by applying a charging current with a pause period in between, but a longer regeneration processing time is required.

  Then, this invention aims at providing the reproduction | regeneration processing method and apparatus which can perform the reproduction | regeneration process stably for a lead storage battery in a short time.

  The regeneration processing method for a lead storage battery according to the present invention is a regeneration processing method for a lead storage battery in which a positive electrode body supporting lead dioxide and a negative electrode body supporting lead are immersed in an electrolyte containing dilute sulfuric acid. An aqueous solution containing carboxymethylcellulose sodium salt is injected into the solution, and a regeneration current having a frequency of 5 kHz to 12 kHz generated by a signal voltage obtained by combining trigger signals having different voltage values is flowed from the positive electrode body to the negative electrode body, and the electrolyte solution is supplied. Heating to maintain a temperature state of 50 ° C. to 60 ° C., and stopping the supply of the regeneration current when the electrolyte rises to a temperature state of 60 ° C. to 70 ° C. with the regeneration current applied. It is characterized by. Furthermore, the electrolytic solution into which the aqueous solution is injected has a concentration of carboxymethyl cellulose sodium salt of 0.5 wt% to 1.0 wt%.

  The regeneration processing device for a lead storage battery according to the present invention is a regeneration processing device for a lead storage battery in which a positive electrode body supporting lead dioxide and a negative electrode body supporting lead are immersed in an electrolyte containing dilute sulfuric acid. Current applying means for flowing a reproduction current having a frequency of 5 kHz to 12 kHz generated by a signal voltage obtained by combining different trigger signals from the positive electrode body to the negative electrode body, a temperature detecting means for detecting the temperature of the electrolytic solution, and carboxymethylcellulose The regeneration current is supplied by the current application means to the electrolyte into which an aqueous solution containing a sodium salt is injected, and the temperature detection means is heated to maintain a temperature state of 50 ° C. to 60 ° C. and the temperature detection And a control means for stopping the supply of current when the detected temperature of the means rises to 60 ° C. to 70 ° C.

  By having the above configuration, an aqueous solution containing carboxymethylcellulose sodium salt is injected into the electrolyte solution, and a reproduction current having a frequency of 5 kHz to 12 kHz generated by a signal voltage obtained by combining trigger signals having different voltage values is generated from the positive electrode body. By flowing through the negative electrode body, the lead sulfate accumulated in the electrode body is removed, and the lead crystal that is the nucleus of the sulfation is destroyed to act to repair the surface of the electrode body.

  In order to continue the surface repairing action of the negative electrode body, it is necessary to heat the electrolyte so that the temperature of the electrolytic solution is maintained at a temperature of 50 ° C to 60 ° C. Since the frequency of the reproduction current to be applied can be easily changed by using the reproduction current generated by the signal voltage obtained by combining the trigger signals having different voltage values, the reproduction current maintained at a temperature state of 50 ° C. to 60 ° C. Can be set in detail. Therefore, the regeneration current for maintaining the temperature of the electrolytic solution in a temperature state of 50 ° C. to 60 ° C. can be accurately set according to the standard of the lead storage battery, and stable regeneration processing can be performed in a short time.

  In addition, the regeneration process is performed while applying a regeneration current that maintains the temperature of the electrolytic solution at a temperature of 50 ° C. to 60 ° C. When the regeneration process is completed, the temperature of the electrolytic solution rises. If the supply of the regeneration current is stopped when the temperature rises to from 70 ° C. to 70 ° C., the regeneration process can be completed reliably.

It is a schematic block diagram regarding embodiment which concerns on this invention. It is a schematic diagram regarding the signal waveform of the trigger signal to generate | occur | produce. It is a schematic diagram regarding the signal waveform of the reproduction current. It is a flow for carrying out reproduction processing of a lead storage battery.

  Hereinafter, embodiments according to the present invention will be described in detail. The embodiments described below are preferable specific examples for carrying out the present invention, and thus various technical limitations are made. However, the present invention is particularly limited in the following description. Unless otherwise specified, the present invention is not limited to these forms.

  FIG. 1 is a schematic configuration diagram relating to an embodiment of the present invention. The lead storage battery 1 that performs the regenerating process includes a plurality of cells that are partitioned by a partition and accommodated in a case. The electrolytic solution 2 is stored inside each cell, and the positive electrode body 3 and the negative electrode body 4 are attached to the electrolytic solution 2 while being immersed therein.

  The positive electrode body 3 has a plate-like electrode body made of lead made porous to increase the surface area, and a lead dioxide layer is formed on the entire surface. The negative electrode body 4 is composed of a porous lead plate electrode body. As the electrolytic solution 2, dilute sulfuric acid is generally used.

  When the lead storage battery 1 is charged, the electrode body takes in water in the electrolytic solution and releases sulfuric acid, and when discharged, the sulfuric acid in the electrolytic solution reacts with the electrode body to generate water. Will come to be. When such charge and discharge are repeated, lead sulfate is deposited and accumulated on the surface of the electrode body, and electrical conduction of the electrode body is inhibited by lead sulfate. For this reason, the discharge area of the electrode body is reduced, the discharge capacity is reduced, and the resistance of the electrode body is increased during charging to generate heat.

  In this embodiment, in order to regenerate the lead storage battery 1 whose performance has been deteriorated in this way, a power supply unit 10 and a rectifier circuit 11 for applying a voltage corresponding to the standard of the lead storage battery 1 are provided. The power supply unit 10 transforms the commercial power supply to a predetermined voltage using a transformer or the like, and the rectifier circuit 11 outputs a DC voltage corresponding to the standard voltage.

  The rectifier circuit 11 is connected to the terminal 3 a of the positive electrode body 3 via a switching element 12 made of a power device, a feedback resistor 13, and an ammeter 14. A terminal of the negative electrode body 4 is grounded, and a voltmeter 15 is connected between the terminal 3 a of the positive electrode body 3.

The control circuit 20 generates a reproduction signal obtained by combining two trigger signals having different voltage values. FIG. 2 is a schematic diagram relating to the signal waveform of the generated trigger signal. In this example, the combination of trigger signals alternately with a voltage value V ₁ of the signal waveform T ₂ where the trigger signal of the signal waveform T ₁ and a voltage value V ₂ which is generated at predetermined intervals a trigger signal is generated at predetermined intervals and it outputs a signal waveform T ₃ as synthesized and reproduced signal. V ₁ is set to a value larger than V ₂ and is preferably set according to the effective value of the reproduction current.

  By using a reproduction signal in which trigger signals having different voltage values are combined, the frequency of the signal waveform can be easily changed and can be easily set to a high frequency. In this case, the frequency of the regenerative signal can be set from 0 Hz to 12 kHz, and the frequency of the output signal waveform can be easily changed at random along the way. This is useful when

  The frequency of the reproduction signal can be set to a high frequency of 12 kHz or higher. However, if the frequency exceeds 12 kHz, the reproduction efficiency is lowered, so the frequency is set to 12 kHz. Although the lead storage battery can be regarded as a capacitor in terms of circuit, it is considered that when a high-frequency current exceeding 12 kHz is applied, the charging function as a capacitor stops functioning, and the regeneration efficiency is lowered.

Further, the edge signal waveforms generated at the rising and falling edges of the trigger signal are canceled out by overlapping the rising and falling edges of the signal waveform T _{1 with} the falling and rising edges of the signal waveform T ₂ , respectively.

  The reproduction signal obtained by synthesizing the trigger signal is input to the variable resistor 22 via the inverter circuit 21 and the voltage value is adjusted. The reproduction signal whose voltage value has been adjusted is input to one input terminal of the amplifier circuit 23. An ON / OFF signal is input from the control circuit 20 to the other terminal of the amplifier circuit 23, and a reproduction signal is output from the amplifier circuit 23 when an ON signal is input.

  The reproduction signal output from the amplifier circuit 23 is input to the amplifier circuit 24. The reproduction signal output from the amplifier circuit 24 is input to the switching element 12 so that a reproduction current corresponding to the reproduction signal flows through the negative electrode body 3. At this time, the reproduction current flowing through the feedback resistor 13 is fed back to the amplifier circuit 24, so that the reproduction current can flow in a stable state. At that time, the high frequency region is cut by LCR in the equivalent circuit of the charging circuit, and the edge portion is shaped into a waveform close to a rounded sine wave.

As shown in FIG. 3, the reproduction current has a waveform having a direct current component I ₁ and a frequency component I ₂ . For example, when a current of 10 A is applied, the direct current component may be set to 4 A and the frequency component may be set to be 6 A as an effective value. Such setting can be easily performed by setting the voltage value and frequency of the trigger signal.

  The mode switch 25 is selected according to the standard of the lead storage battery, and outputs a selection signal corresponding to the lead storage battery to be regenerated to the control circuit 20, and the control circuit 20 regenerates based on the input selection signal. Generate a signal.

  The temperature measuring device 30 measures a detection signal from a temperature sensor 31 that detects the temperature of the electrolytic solution provided in each cell of the lead storage battery, and transmits it to the control circuit 20. The control circuit 20 stops the supply of the regeneration current when the temperature suddenly rises after the regeneration current is applied or when the regeneration process is completed after the regeneration current is applied and the temperature rises to 60 ° C. to 70 ° C.

  In a lead storage battery to be regenerated, a regenerative current having a predetermined frequency is passed from the positive electrode body 3 to the negative electrode body 4 to generate heat. Since the lead storage battery can be handled as a capacitor in the equivalent circuit, it is possible to increase the heat generation amount by increasing the frequency of the regenerative current and efficiently increase the temperature of the electrolytic solution.

  Also, by pre-injecting an aqueous solution containing sodium carboxymethylcellulose into the electrolyte of the lead storage battery to be regenerated, lead sulfate accumulated in the electrode body is removed and lead crystals that are the core of sulfation are destroyed. Can do. The concentration of carboxymethyl cellulose sodium salt in the electrolytic solution into which the aqueous solution has been injected is preferably 0.5% by weight to 1.0% by weight. If the concentration of carboxymethylcellulose sodium salt is lower than 0.5% by weight, a sufficient sulfation repair effect cannot be obtained. If it exceeds 1.0% by weight, the charge / discharge performance of the regenerated lead-acid battery may be affected. become.

  At that time, by maintaining the temperature of the electrolytic solution at 50 ° C. to 60 ° C., the repairing action of such sodium carboxymethyl cellulose can be promoted and the regeneration treatment time can be shortened. In order to maintain the temperature of the electrolytic solution at 50 ° C. to 60 ° C., the frequency of the regeneration current can be adjusted and set easily. In this case, it is possible to efficiently apply a regeneration current having a frequency of 5 kHz to 12 kHz and maintain the temperature of the electrolyte at 50 ° C. to 60 ° C.

  FIG. 4 is a flow for regenerating the lead storage battery. First, an acceptance inspection of the collected used lead storage battery is performed (S100). The collected lead-acid batteries are checked for standards and date of manufacture, and the appearance of the container body and each cell is inspected, and those that are judged to be unrecyclable, such as those that are short-circuited based on the inspection results, are excluded.

  Then, those having no problem according to the inspection result are washed and a charge test is performed (S101). First, the voltage and specific gravity of each cell is measured to check whether it can be energized. For those that can be energized, a known charger is connected to the lead storage battery and a charging voltage corresponding to the standard is applied to perform a charging test. Done. The charging characteristics are checked by measuring the voltage, specific gravity and temperature of the electrolysis solution of each cell during the charging period. After the charge test, a known discharger is connected and a discharge test is performed (S102). The discharge characteristics are checked by measuring the voltage and discharge time of each cell during the discharge period.

  In such a charge test and discharge test, a cell in which the electrolyte solution is turbid or a cell having an extremely short discharge time is replaced with another regenerated cell as a defective cell.

  Next, a regeneration process is performed on the lead storage battery whose defective cell has been replaced (S103). As described above, a regeneration current capable of maintaining the electrolyte of the lead storage battery at 50 ° C. to 60 ° C. is set by a test, an aqueous solution containing carboxymethyl cellulose sodium salt is injected into the electrolyte of the lead storage battery, and carboxymethyl cellulose sodium salt Is set to 0.5 wt% to 1.0 wt%.

  A regeneration current is applied after injecting the aqueous solution. By applying the regenerative current, the electrolysis solution is heated and the temperature rises. However, if there is a cell in which the temperature of the electrolyte solution is constantly measured by the temperature measuring device 30 and the temperature rises rapidly, a warning signal is sent to the control circuit. 20 is transmitted.

  For cells in which regeneration processing is normally performed, regeneration processing is performed for 6 to 7 hours, and charging is completed. At that time, the electrolytic solution changes at 50 ° C to 60 ° C during the charging period, but the temperature of the electrolytic solution rises to 60 ° C to 70 ° C upon completion of charging. It can be confirmed that the processing is completed. When the regeneration process is not performed normally, the temperature of the electrolyte solution suddenly increases due to the application of the regeneration current, and the electrolyte solution boils at about 80 ° C. Remove as defective cell and replace with regenerated cell.

  A charge / discharge test after regeneration is performed on the lead storage battery thus subjected to regeneration processing (S104). Charging / discharging is repeated a plurality of times, and the voltage, specific gravity, and electrolyte temperature of each cell are measured, and a performance test is performed to determine whether the measured value satisfies the basic set value (S105). Those with no problems in performance inspection are shipped as recycled lead-acid batteries.

  When the CCA value was measured by repeating charge and discharge three times for a lead storage battery regenerated according to the present invention and a lead storage battery regenerated using a known regenerating liquid, the present invention compared to before the regenerating process. It was up 50%, but the known one was up 20%. As a result, it was shown that the reproduction processing according to the present invention has much higher reproduction efficiency than the conventional reproduction processing.

DESCRIPTION OF SYMBOLS 1 Lead acid battery 2 Electrolyte 3 Positive electrode body 4 Negative electrode body
10 Power supply
11 Rectifier circuit
12 Switching element
13 Feedback resistor
14 Ammeter
15 Voltmeter
20 Control circuit
21 Inverter
22 Variable resistor
23 Amplifier circuit
24 Amplifier circuit
25 Mode switch
30 Temperature measuring device
31 Temperature sensor

Claims (3)

  A regeneration method for a lead storage battery in which a positive electrode body supporting lead dioxide and a negative electrode body supporting lead are immersed in an electrolyte containing dilute sulfuric acid, and an aqueous solution containing carboxymethylcellulose sodium salt is injected into the electrolyte A regeneration current having a frequency of 5 kHz to 12 kHz generated by a signal voltage obtained by combining trigger signals having different voltage values is passed from the positive electrode body to the negative electrode body so as to maintain the electrolyte in a temperature state of 50 ° C to 60 ° C. A regeneration method for a lead storage battery, wherein the supply of the regeneration current is stopped when the electrolyte rises to a temperature of 60 ° C. to 70 ° C. with the regeneration current applied.   2. The regeneration processing method according to claim 1, wherein the electrolyte solution into which the aqueous solution is injected has a carboxymethyl cellulose sodium salt concentration of 0.5 wt% to 1.0 wt%.   A lead-acid battery regeneration processing device in which a positive electrode body supporting lead dioxide and a negative electrode body supporting lead are immersed in an electrolyte containing dilute sulfuric acid, which is generated by a signal voltage obtained by combining trigger signals having different voltage values. Current applying means for flowing a reproduction current having a frequency of 5 kHz to 12 kHz from the positive electrode body to the negative electrode body, temperature detecting means for detecting the temperature of the electrolytic solution, and the electrolytic solution into which an aqueous solution containing carboxymethylcellulose sodium salt has been injected. The regeneration current is supplied by the current application means to heat the temperature detection means so that the temperature detected by the temperature detection means is maintained at a temperature of 50 ° C. to 60 ° C. and the temperature detection temperature of the temperature detection means is increased to 60 ° C. to 70 ° C. And a control means for stopping the supply of electric current in the event of failure.

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