JP6519793B2 - Method of charging control valve type lead storage battery - Google Patents

Description

  The present invention relates to a method for charging a valve-regulated lead-acid battery.

  The valve-regulated lead-acid battery is a secondary battery excellent in safety and reliability, and is used in various applications. For example, it is used for DC power supply for power storage, especially telephone switches for general line use, and it is operated by emergency power supply, so that charging methods such as trickle charge and float charge are used to keep the battery always charged. . Since these charging methods are always charged for the purpose of compensating for storage battery capacity loss due to self-discharge, the cause of battery deterioration is generally mainly corrosion of the positive electrode current collector. Various studies have been conducted to prevent deterioration of the positive electrode current collector due to corrosion. For example, in Patent Document 1, in a method of charging a lead storage battery as a power source such as UPS, the trickle life of the battery is measured by measuring the trickle charge current of the battery and changing the charge voltage according to the change of the trickle charge current. SUMMARY OF THE INVENTION A method of charging a lead-acid battery is intended to prolong the life of the battery. Further, in Patent Document 2, a lead-acid battery is provided by arranging variable resistors in parallel with individual lead-acid batteries used in series connection and performing trickle charge to individually adjust the resistance value of the variable resistors. A charging method aiming at prolonging the life of the battery is disclosed.

JP-A-8-308125 JP, 2013-168222, A

  However, the method described in Patent Document 1 fluctuates the charging voltage according to the change in the trickle charging current of the entire series-connected lead-acid battery, the current value is partially low, and the fully charged state is maintained. Lead-acid batteries may be generated. When a lead storage battery that can not maintain a fully charged state occurs, the battery capacity of the entire power storage device is reduced, and the life of the power storage device is likely to be shortened.

  Further, Patent Document 2 can perform optimum trickle charge on individual lead-acid batteries used in series connection, and can achieve long life, but the life performance according to the Arrhenius law due to battery heat generation The decline can not be suppressed.

  An object of the present invention is to provide a control valve type lead-acid battery charging method capable of suppressing heat generation generated during trickle charge and achieving long life in a control valve type lead-acid battery operated in standby use. .

  The specific means for solving the said subject are as follows.

  A charging method for a valve-regulated lead-acid battery operated at a state of charge of 95 to 100%, wherein the fully charged state is 100%, wherein voltage amplitude is set at a frequency of 100 Hz to 8000 Hz when charging the valve-regulated lead-acid battery. The charge method of a control valve-type lead acid battery including the process made to apply.

  In the above, it is preferable that the charging is constant voltage charging and that the amplitude is applied at a voltage of 0.001 to 0.05 times the voltage in the constant voltage charging.

  ADVANTAGE OF THE INVENTION According to this invention, the charge method of the control valve-type lead acid battery which is excellent in the lifetime characteristic can be provided.

It is a perspective view showing member composition of an example of control valve-type lead acid battery.

<Method of charging control valve type lead storage battery>
The charging method in the present invention includes the step of applying a voltage amplitude at a frequency of 100 Hz to 8000 Hz during charging. In the application of the voltage amplitude, the voltage is preferably 0.001 to 0.005 times the constant voltage charging voltage. The frequency is preferably 1000 Hz to 5000 Hz from the viewpoint of further reducing the temperature rise of the valve-regulated lead-acid battery.

  There are two types of control valve type lead-acid batteries: retainer type and gel type. The retainer type is a mat type separator (glass separator) made of fine glass fibers inserted between a positive electrode plate and a negative electrode plate to hold sulfuric acid electrolyte necessary for charge and discharge of the battery and to separate the two electrodes. It is.

The control valve type lead storage battery is used as an uninterruptible power supply, an emergency power supply, and the like.
When using a control valve-type lead storage battery as the uninterruptible power supply or the emergency power supply, it is preferable that the standby state is a fully charged state. However, when stored for a long time in a fully charged state, the rated amount of performance may not be exhibited or may not be used because the amount of electricity stored during use is reduced due to self-discharge and the like. Therefore, trickle charge is performed to compensate for the self-discharge. When performing trickle charge, the state of charge of the control valve type lead-acid battery (hereinafter sometimes referred to as SOC. SOC is an abbreviation for State Of Charge) is 95 to 100%, but from the viewpoint of life performance. Is preferably 98 to 100%. For trickle charge, it is preferable to apply a voltage slightly higher than the nominal voltage to the electrodes of a control valve type lead-acid battery and to charge with a constant voltage. The trickle charge naturally reduces the charge current as it approaches a fully charged state, and has the effect of preventing overcharge. The charging voltage should be set appropriately to prevent overcharging, or a current limiting circuit should be provided to prevent battery life shortening due to excessive current.

The charge in the present invention is preferably a trickle charge. The trickle charge is preferably constant voltage charge at a voltage of 1.11 to 1.15 times the nominal voltage of the control valve type lead-acid battery. It is preferable that the current at the time of the constant voltage charging is direct current. It is preferable to include the step of applying a voltage amplitude at a frequency of 100 Hz to 8000 Hz during the constant voltage charging, and from the viewpoint of being able to further reduce the temperature rise of the control valve type lead-acid battery, the frequency is 100 Hz to 5000 Hz. Is more preferable, and 500 Hz to 5000 Hz is more preferable. When the frequency is less than 100 Hz, the corrosion reaction at the lattice / active material interface due to the voltage amplitude is likely to occur selectively, and the amount of corrosion may be large. Also, if it exceeds 8000 Hz, the temperature of the valve-regulated lead-acid battery may increase and the life may be reduced. The voltage at the application of the voltage amplitude is preferably 0.001 to 0.05 times the voltage at constant voltage charging. If the voltage swing exceeds 0.05 times with respect to the constant voltage charge, when the voltage swings in the negative direction, the voltage may become more monumental than the open circuit voltage of the battery and the charge state may not be maintained.
<Preparation of valve-regulated lead-acid battery>
The positive electrode active material is prepared by adding a paste of red lead to lead powder containing lead monoxide as a main component, mixing predetermined amounts of water and dilute sulfuric acid, and kneading the resulting paste-like active material into a lead alloy current collector. It is filled and aged and dried under predetermined conditions. Here, the surface area of the active material of the positive electrode plate in a fully charged state can be adjusted within a certain target range after formation, by changing the addition amount of water and dilute sulfuric acid, and aging and drying conditions.

  The negative electrode active material is prepared by adding an additive to lead powder containing lead monoxide as a main component, mixing, adding predetermined amounts of water and dilute sulfuric acid and kneading the paste-like active material into a lead alloy current collector It is filled and aged and dried under predetermined conditions. Here, the surface area of the active material of the negative electrode plate in a fully charged state can be adjusted within a certain range after formation, by changing the addition amounts of the additive, water, and dilute sulfuric acid, and the aging and drying conditions.

  Furthermore, it is possible to adjust the surface area of the positive and negative electrode active materials by changing the formation conditions.

  Further, the mass of the positive and negative electrode active materials can be adjusted by changing the amount of the paste-like active material filled in the current collector made of lead alloy.

  As additives to be added to the paste-like negative electrode active material, a strengthening acid-resistant fiber, a lead sulfate crystal growth suppressing additive, and a shrinkproofing agent are used. As the acid resistant fiber for reinforcement, acrylic fiber, polyester fiber, polyethylene terephthalate (PET) fiber or the like can be used, and it is desirable to use PET fiber from the viewpoint of price and acid resistance. By using the reinforcing acid resistant fiber, when the lattice substrate is filled with the active material, the active material can be prevented from coming off and coming off. It is common to use barium sulfate as a lead sulfate crystal growth inhibiting additive. When barium sulfate is used, it does not dissolve in the electrolytic solution and stays in the active material, so that it becomes a crystal nucleus of lead sulfate generated at the time of discharge and can form fine lead sulfate. A lignin sulfonate is used as a shrinkproofing agent, and there are a synthetic lignin and a natural lignin derived from trees, and a natural lignin having long-term stability is used for long-term standby use applications. desirable. By adding lignin, it is possible to prevent the negative electrode active material from being changed in form and aggregated during charge and discharge, and to maintain the surface area of the active material. Also, by not including carbon, it is possible to reduce the trickle current during trickle charge, and the life performance can be sufficiently secured.

  As an additive to be added to the paste-like positive electrode active material, a reinforcing acid-resistant fiber, red lead, is used. As a reinforcing acid resistant fiber, an acrylic fiber, a polyester fiber, a PET fiber or the like can be used, and it is desirable to use a PET fiber in terms of price and acid resistance. By using the reinforcing acid resistant fiber, when the lattice substrate is filled with the active material, the active material can be prevented from coming off and coming off. "Peduntan" can improve the chemical conversion during cell formation, increase the surface area of the positive electrode active material, increase the utilization of the positive electrode active material, and achieve both the chemical conversion of the active material and the durability of the active material. It is desirable to add 5 to 25% by mass to the lead powder in order to cause When the amount of red lead is less than 5%, the effect of red lead is not sufficiently exhibited, and when it is 25% or more, the durability of the active material is significantly reduced.

  The lead alloy for forming the positive electrode current collector is made of a lead-calcium-tin alloy. By setting the calcium content and tin content to calcium: 0.08% by mass and tin: 1.6% by mass with respect to lead, the alloy composition becomes dense and a positive electrode current collector excellent in corrosion resistance is formed. It is possible to

  The lead alloy for forming the negative electrode current collector is not particularly limited, but pure lead, calcium-tin alloy and antimony alloy are generally used, and in view of life performance and ease of manufacturing, It is desirable to use a calcium-tin alloy.

  The positive and negative electrode plates are obtained by filling the above-described paste-like active materials in a current collector, and ripening and drying. The current collector can be manufactured by an expanding method, a casting method, a forging method, or the like.

  In the control valve type lead storage battery of the present embodiment, for example, as shown in FIG. 1, a lead storage battery is assembled, and a predetermined amount of electrolytic solution is injected to perform battery formation.

  When a plurality of cell chambers are provided in the battery case, the electrode plate group is accommodated in each cell chamber, and the electrode plate group accommodated in the adjacent cell chamber and the strap of the opposite polarity are connected to each other. Lead-acid battery with rated voltage and rated capacity is configured. Moreover, in the case of a single cell battery case, terminals of a plurality of lead storage batteries can be connected in parallel or in series using conductive plates to configure a battery of a predetermined voltage and capacity.

  Hereinafter, examples of the present invention will be described.

  In the following examples and comparative examples, the interelectrode temperature during charging was measured by the following method.

A fast chargeable / dischargeable bipolar power supply was connected to a 38 Ah-12 V control valve type lead-acid battery manufactured by Shin-Kobe Electric Machinery Co., Ltd., which is fully charged (SOC = 100%). With the cell on the positive electrode terminal side of the control valve type lead-acid battery as (1), the K thermocouple was inserted from the liquid inlet into the (1) to (3) cell retainer, and the temperature inside the battery was measured. The temperature in the battery was recorded at 1 Point / Min using GL-800 manufactured by GRAPHTEC.
Example 1
After standing for 24 hours in a 45 ° C. constant temperature bath, a constant voltage charge of 13.65 V (about 1.14 times the nominal voltage) with a bipolar power supply (manufactured by NF Circuit Design Block, product name: BP4610) For 48 hours (about 100% charged). Thereafter, during constant-voltage charging, a voltage amplitude of ± 50 mV (about 0.0037 times the voltage at constant-voltage charging) was superimposed at 500 Hz for 48 hours, and the inter-electrode temperature was measured for 48 hours. At this time, the temperature before measurement was 25.1 ° C., the temperature after 48 hours was 28.4 ° C., and the temperature rise was 3.3 ° C.
(Example 2)
After leaving in a thermostat at 45 ° C. for 24 hours, constant-voltage charging at 13.65 V was performed for 48 hours using a bipolar power supply. Thereafter, during constant voltage charging, a voltage amplitude of ± 50 mV was superposed at 800 Hz for 48 hours, and the temperature between the electrodes was measured for 48 hours. At this time, the temperature before measurement was 25.2 ° C., the temperature after 48 hours was 28.7 ° C., and the temperature rise was 3.5 ° C.
(Example 3)
After leaving in a thermostat at 45 ° C. for 24 hours, constant-voltage charging at 13.65 V was performed for 48 hours using a bipolar power supply. Thereafter, during constant voltage charging, a voltage amplitude of ± 50 mV was superposed at 1000 Hz for 48 hours, and the temperature between the electrodes was measured for 48 hours. At this time, the temperature before measurement was 25.0 ° C., the temperature after 48 hours was 28.6 ° C., and the temperature rise was 3.6 ° C.
(Example 4)
After leaving in a thermostat at 45 ° C. for 24 hours, constant-voltage charging at 13.65 V was performed for 48 hours using a bipolar power supply. Thereafter, during constant voltage charging, a voltage amplitude of ± 50 mV was superposed at 2000 Hz for 48 hours, and the temperature between the electrodes was measured for 48 hours. At this time, the temperature before measurement was 25.1 ° C., the temperature after 48 hours was 28.8 ° C., and the temperature rise was 3.7 ° C.
(Example 5)
After leaving in a thermostat at 45 ° C. for 24 hours, constant-voltage charging at 13.65 V was performed for 48 hours using a bipolar power supply. Thereafter, during constant voltage charging, a voltage amplitude of ± 50 mV was superimposed at 5000 Hz for 48 hours, and the temperature between the electrodes was measured for 48 hours. At this time, the temperature before measurement was 24.8 ° C., the temperature after 48 hours was 29.3 ° C., and the temperature rise was 4.5 ° C.
(Comparative example 1)
After leaving in a thermostat at 45 ° C. for 24 hours, constant-voltage charging at 13.65 V was performed for 48 hours using a bipolar power supply. At this time, the temperature before measurement was 24.9 ° C., the temperature after 48 hours was 30.0 ° C., and the temperature rise was 5.1 ° C.
(Comparative example 2)
After leaving in a thermostat at 45 ° C. for 24 hours, constant-voltage charging at 13.65 V was performed for 48 hours using a bipolar power supply. Thereafter, during constant voltage charging, a voltage amplitude of ± 50 mV was superposed at 10000 Hz for 48 hours, and the temperature between the electrodes was measured for 48 hours. At this time, the temperature before measurement was 25.2 ° C., the temperature after 48 hours was 30.6 ° C., and the temperature rise was 5.4 ° C.
<Test result>
In Examples 1 to 5, the temperature between the electrodes was lower than in Comparative Examples 1 and 2.

  The lifetime of a controlled valve lead acid battery charged with a constant voltage such as trickle charge is generally determined by the corrosion of the positive grid. The corrosion of the positive grid is accelerated by the temperature rise according to the Arrhenius law. Since the normal constant voltage charging (Comparative Example 1) in which the voltage amplitude is not applied (Comparative Example 1) is the temperature between the electrodes operated in the related art, the application of the voltage amplitude is more It can be expected that the temperature between the electrodes is lowered and the life can be extended.

  From the results of Examples 1 to 5, the rise in the interelectrode temperature is particularly low at 500 Hz to 5000 Hz, the interelectrode temperature rises at around 10000 Hz, and the voltage amplitude of Comparative Example 1 is superimposed at 10000 Hz as in Comparative Example 2. The temperature rise between the electrodes was higher than no constant voltage charging. Up to around 10000 Hz, it is thought that light charging and discharging frequently occur at the electrodes due to the voltage amplitude, and the temperature between the electrodes is lowered by the endothermic reaction during charging and discharging. In addition, even if the voltage rises to the positive side and the charging reaction occurs excessively and the gas generation reaction occurs, the gas absorption reaction occurs at the negative electrode, and the temperature between the electrodes is considered to decrease. The reason why the start of the rise in the interelectrode temperature starts at around 10000 Hz is presumed to be the frequency band in which the transfer resistance of electrons or ions is apparent from around 10000 Hz. In addition, when the frequency is further increased, the electric resistance of the battery component is also manifested, so the temperature rises more, and the inter-electrode temperature is considered to be higher than the constant voltage charging in which the voltage amplitude is not superimposed.

  According to the present invention, in the control valve-type lead storage battery operated in standby use, it is possible to provide a method for charging the control valve-type lead storage battery which suppresses heat generation generated during trickle charge and is excellent in life characteristics.

  DESCRIPTION OF SYMBOLS 1 ... Control valve-type lead storage battery, 2 ... Positive electrode plate, 3 ... Negative electrode plate, 4 ... Separator, 5 ... Battery case, 6 ... Lid

Claims (2)

  A charging method for a valve-regulated lead-acid battery operated at a state of charge of 95 to 100%, wherein the fully charged state is 100%, wherein voltage amplitude is set at a frequency of 100 Hz to 8000 Hz when charging the valve-regulated lead-acid battery. The charge method of a control valve-type lead acid battery including the process made to apply.   The method for charging a valve-regulated lead-acid battery according to claim 1, wherein the charge is constant voltage charge, and an amplitude is applied at a voltage of 0.001 to 0.05 times the voltage in the constant voltage charge.

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