WO2012053056A1

WO2012053056A1 - Method for producing batteries

Info

Publication number: WO2012053056A1
Application number: PCT/JP2010/068361
Authority: WO
Inventors: 真一郎橘内; 和雄生田; 紀博地久里
Original assignee: トヨタ自動車株式会社
Priority date: 2010-10-19
Filing date: 2010-10-19
Publication date: 2012-04-26

Abstract

The problem addressed is the provision of a method for producing batteries that uses energy efficiently when producing batteries. The method for producing batteries (1) includes: an aging step for housing a battery within a thermostatic chamber (100) for keeping the chamber temperature at a constant temperature using a temperature adjustment device (110) driven by electrical energy, and performing an aging process on the battery; and a discharge step for discharging the battery; wherein at least some of the electrical energy retrieved from the discharged battery in the discharge step is used as at least some of the electrical energy for driving the temperature adjustment device in the aging step for another battery.

Description

Battery manufacturing method

The present invention relates to a battery manufacturing method including an aging process for aging a battery and a discharging process for discharging the battery.

In recent years, secondary batteries such as rechargeable lithium ion secondary batteries (hereinafter also simply referred to as batteries) have been used as power sources for driving vehicles such as hybrid cars and electric cars.

Regarding such a battery, for example, Patent Document 1 discloses an aging treatment method in which the battery is stored at a storage temperature of 40 ° C. or higher and 90 ° C. or lower. According to Patent Document 1, such an aging process is performed on an initial battery that has just been manufactured, whereby an increase in internal resistance of the battery over time can be suppressed.

JP 2000-340262 A

However, in Patent Document 1, aging treatment is performed using a thermostatic bath. The thermostat is usually kept constant by adjusting the temperature in the thermostat using a temperature control device such as a heater that uses electric energy supplied from a commercial power source as a drive source. For this reason, while using the thermostat which performs an aging process, an electrical energy is consumed with a temperature control apparatus.

On the other hand, for example, in the final stage of battery manufacture, the state of charge (SOC) of the battery may be adjusted to a predetermined value. This is because the battery SOC is adjusted to an SOC that is unlikely to deteriorate, thereby suppressing the progress of deterioration of the battery during the period from manufacture to use.

In this way, when adjusting the SOC to a predetermined value, the battery may be discharged in order to lower the SOC of the battery to a predetermined value using the power supply device. In this discharge, the electric energy is often consumed as heat by flowing through a resistor or the like. That is, in the aging process, heat energy is obtained using electric energy, while in the adjustment of the SOC of the battery, the electric energy is discarded as heat energy.

The present invention has been made in view of such a problem, and provides a battery manufacturing method that efficiently uses energy in battery manufacturing.

One embodiment of the present invention includes an aging process in which a battery is accommodated in a temperature-controlled room that maintains a constant room temperature using a temperature control device that is driven by electric energy, and an aging process is performed on the battery. A discharge step for discharging the battery, wherein the discharge step includes adjusting the temperature in the aging step for at least a part of the electric energy extracted from the discharged battery. A battery manufacturing method used for at least a part of electric energy for driving the apparatus.

In the battery manufacturing method described above, at least a part of the electric energy taken out of the battery in the discharging process is used as at least a part of the electric energy for driving the temperature control device in the aging process for other batteries. For this reason, consumption of electric energy can be suppressed as a whole by using the electric energy derived from the battery in the temperature adjusting device, and the energy can be used efficiently.

The temperature adjusting device adjusts the room temperature of the temperature-controlled room. For example, the heater or the cooler (chiller), the temperature sensor, and the heater or cooler (chiller) based on the room temperature detected by the temperature sensor. And an apparatus having a control unit for controlling the driving of the apparatus. In the aging process, at least a part of the electric energy extracted from the battery in the discharging process is used as at least a part of the electric energy for driving the temperature control device. For this reason, for example, even if a part of the electric energy extracted from the battery is used as a part of the electric energy for driving the temperature control device, a part of the extracted electric energy is used for all the electric energy for driving the temperature control device. Even if it is used, all of the extracted electric energy is used for a part of the electric energy for driving the temperature adjusting device, or all the extracted electric energy is used for all of the electric energy for driving the temperature adjusting device. good.

Furthermore, in the method for manufacturing a battery described above, the discharging step is started for each battery group including the same number of batteries, and the discharging step for one battery group. It is preferable that the battery is manufactured by adjusting the timing so that the end of the discharge in step 1 coincides with the start of discharge in the discharge step of the other battery group.

In the above-described battery manufacturing method, the discharging process is started for each battery group including the same number of batteries, and at the end of discharging in the discharging process of one battery group, and the like. The timing is adjusted so that the discharge start timings in the discharge process of the battery groups coincide. For this reason, in this discharge process, it is possible to always discharge a certain number of batteries. Therefore, the electric energy can be stably sent from the battery being discharged in the discharging process to the temperature adjusting device, and the adjustment of the supply destination of the electric energy consumed in the temperature-controlled room becomes easy.

Furthermore, in the battery manufacturing method described above, the discharging step is preferably a battery manufacturing method in which the discharging of the battery is performed by constant power discharge.

In the battery manufacturing method described above, since the battery is discharged by constant power discharge in the discharging step, constant power per unit time can always be obtained from the battery discharged in the discharging step. Therefore, there is no fluctuation in the electric power supplied from the discharged battery, and it becomes easier to adjust the supply destination of the electric energy consumed in the temperature-controlled room.

It is a perspective view of the battery concerning an embodiment. It is a flowchart which shows each process of the manufacturing method of the battery concerning embodiment. It is explanatory drawing which shows the process of the manufacturing method of the battery concerning embodiment.

(Embodiment)
Next, embodiments of the present invention will be described with reference to the drawings. First, the battery 1 according to the present embodiment will be described with reference to FIG. The battery 1 is a lithium ion secondary battery that includes a belt-like positive electrode plate 20, a negative electrode plate 30, and a separator 40, and forms a wound power generation element 10 that is wound (see FIG. 1). In addition, the battery 1 accommodates the electric power generation element 10 in the battery case 80, as shown in FIG.

Subsequently, a method for manufacturing the battery 1 will be described with reference to FIGS. As shown in FIG. 2, the manufacturing method of the battery 1 proceeds in the order of a battery assembly process, an initial charging process, an aging process, a self-discharge inspection process, a discharging process, a charge adjustment process, and an internal resistance inspection process. In this embodiment, each process of the manufacturing method of the battery 1 is operated for 24 hours.

First, the battery assembly process will be described. A paste (not shown) in which a binder, positive electrode active material particles, and a conductive material are dispersed and kneaded in a solvent is applied to both main surfaces of a strip-shaped aluminum foil, dried, and the dried paste is compressed. A positive electrode plate 20 was produced. On the other hand, a paste (not shown) in which a binder and negative electrode active material particles are dispersed and kneaded in a solvent is applied to both main surfaces of a strip-shaped copper foil, dried, and the dried paste is compressed to form a negative electrode plate 30 was produced.

The power generation element 10 is made by winding the positive electrode plate 20 and the negative electrode plate 30 produced as described above together with the two strip-

shaped separators

40 and 40. After a current collecting member (not shown) is welded to the power generation element 10, the power generation element 10 is enclosed in a battery case 80 together with an electrolyte (not shown) to assemble the battery 1 (see FIG. 1). .

Next, a plurality (25 in this embodiment) of

batteries

1 and 1 are mounted and fixed on a jig (not shown). Thereby, each process can be performed simultaneously about 25

batteries

1 and 1.

Next, an initial charging process is performed. Note that the initial charging process is started at intervals of a predetermined time (in this embodiment, 50 seconds) for a plurality (25) of

batteries

1 and 1 mounted on one jig described above. In addition, each

battery

1 and 1 is charged. Specifically, a power supply device (not shown) is connected to each of the

batteries

1 and 1, and constant current-constant voltage charging is performed, so that the charging state of the battery 1 is equivalent to SOC 100%. Thereafter, the positive terminal and the negative terminal of the power supply device are removed from each of the

batteries

1 and 1.

Next, an aging process is performed on the battery 1 that has undergone the initial charging process described above. In this aging process, a constant temperature chamber 100 having a predetermined temperature T (in this embodiment, 50 ° C.) is used, and the battery 1 is left in the constant temperature chamber 100 for a predetermined period (in this embodiment, 15 hours). It is a process. By performing this aging process, the reactivity immediately after charging the battery in the initial stage can be suppressed, and the safety can be improved.

The temperature-controlled room 100 used for this aging process has a temperature control device 110 capable of keeping the room temperature constant at a predetermined temperature T (50 ° C.) (see FIG. 3). The temperature adjusting device 110 includes a first heater 111 and a second heater 112 that can generate heat, a fan 113 for blowing air warmed by the first heater 111 and the second heater 112, and a first heater. A first switch 114 that is a switch 111, a second switch 115 that is a switch of the second heater 112, and a fan switch 116 that is a switch of the fan 113. Further, the temperature sensor 117 that measures the room temperature of the temperature-controlled room 100 and the room temperature are detected through the temperature sensor 117, and on / off of the first switch 114, the second switch 115, and the fan switch 116 is controlled. A control unit 118 is included.

Among these, the control unit 118 controls the driving of the first heater 111, the second heater 112, and the fan 113 based on the detected room temperature of the temperature-controlled room 100. Thereby, the temperature control apparatus 110 keeps the room temperature of the temperature-controlled room 100 constant at the predetermined temperature T (50 ° C.).

Also, the second heater 112 and the fan 113 are driven using electrical energy supplied from a commercial power source. On the other hand, the first heater 111 is connected to the battery 1 to be discharged in a discharge process to be described later, and generates heat with electric energy extracted from the battery 1. Therefore, the temperature control device 110 is necessary for maintaining the room temperature by turning on the first switch 114 when the electric energy is released from the battery 1 to be discharged in the discharge process described later. Most of the heat energy is covered by the heat generated by the first heater 111. At this time, if the room temperature of the temperature-controlled room 100 decreases from the predetermined temperature T, the control unit 118 temporarily turns on the second switch 115 to raise the temperature of the room to the second heater 112. It will be covered by the fever.

On the other hand, for example, before starting the aging process, the temperature of the temperature-controlled room 100 is raised from room temperature to a predetermined temperature T (50 ° C.) or when there is no battery 1 to be discharged in the discharging process, the control unit 118. Turns on the second switch 115 to cause the second heater 112 to generate heat using electrical energy supplied from a commercial power source. If the number of batteries 1 to be discharged in the discharging process increases, the first heater 111 is caused to generate heat by the electric energy released from the battery 1 and the heat generation in the second heater 112 is suppressed accordingly. By doing in this way, consumption of the electrical energy supplied from a commercial power supply can be suppressed, making the temperature control apparatus 110 function.

The aging process is performed using the above-described temperature-controlled room 100. Similar to the initial charging process described above, the aging process is started at predetermined intervals (50 seconds) for a plurality (25) of

batteries

1 and 1 mounted on one jig described above.

The battery 1 is inserted into the room of the temperature-controlled room 100 in which the room temperature is kept constant at a predetermined temperature T (50 ° C.) by the temperature control device 110 until the predetermined time (15 hours) elapses. Leave in 100. The control unit 118 of the temperature control device 110 continuously drives the fan 113 and the first heater 111, and always detects the room temperature of the temperature-controlled room 100 using the temperature sensor 117 disposed in the room of the temperature-controlled room 100. Then, the second heater 112 is energized as necessary to keep the room temperature in the temperature-controlled room 100 constant at a predetermined temperature T (50 ° C.).

Next, a self-discharge inspection process is performed on the battery 1 that has been subjected to the aging process. Similar to the initial charging process and the aging process described above, the self-discharge inspection process is started at predetermined intervals (50 seconds) for a plurality (25) of

batteries

1 and 1 mounted on one jig described above. To do.

Whether the battery 1 having a predetermined SOC is allowed to stand for a predetermined period (10 days) in an environment of a constant temperature (in this embodiment, 25 ° C.), and whether the battery 1 after being left is lower than the predetermined SOC Inspect whether. Specifically, the open circuit voltage BVO of the battery 1 after standing for a predetermined period is measured for each battery, and it is determined whether or not the open circuit voltage BVO after standing is smaller than a predetermined value. In addition, when the open circuit voltage BVO after stationary is more than predetermined value, it progresses to the charge adjustment process of the next process. On the contrary, the battery 1 whose open circuit voltage BVO after standing is smaller than a predetermined value is excluded at the time of shipment.

Next, the battery 1 is subjected to a discharging process. This discharging step is a step of discharging the battery 1 with constant power over 40 minutes using the constant power discharging device 200 and the control device 210 described below. This discharging step is performed by connecting a plurality (25 in this embodiment) of

batteries

1 and 1 on the same jig in series. Thereby, 25

batteries

1 and 1 can be discharged simultaneously.

In this discharge step, the battery 1 and the temperature control device 110 are passed through the plurality (50 in this embodiment) of constant

power discharge devices

200, 200 shown in FIG. 3 and the plurality of constant

power discharge devices

200, 200. The control device 210 for controlling whether or not to energize each is used. Among them, the constant power discharge device 200 includes a circuit unit 201 configured to discharge electric energy from the battery 1 by constant power discharge, and the battery 1 and the temperature control device 110 through the circuit unit 201. It has the switch part 202 which turns on / off electricity with the 1st switch 114 (refer FIG. 3).

Further, the control device 210 has a timepiece (not shown), and on the basis of this timepiece, the

switch units

202 and 202 of the constant

power discharge devices

200 and 200 are turned on / off, respectively. It should be noted that the discharge process is started at intervals of a predetermined time TM (100 seconds in the present embodiment) for the plurality (50) of

batteries

1 and 1 mounted on the two jigs described above. Specifically, one constant power discharge device 200 is connected to 25

batteries

1 and 1 for one jig. Therefore, in order to start the discharge process every predetermined time TM (100 seconds), the control device 210 includes the

switch units

202 and 202 of the two constant

power discharge devices

200 and 200 connected to the

batteries

1 and 1, respectively. Turn on at the same time.

Further, in the discharging step, constant power discharge is performed on the

batteries

1 and 1 for 40 minutes, so that the control device 210 switches the switch portions of the two constant

power discharge devices

200 and 200 40 minutes after the switch portion 202 is turned on. Each of 202 and 202 is turned off.

At this time, the control device 210 ensures that the discharge end timing of the

batteries

1 and 1 mounted on the two jigs coincides with the discharge start timing of the

batteries

1 and 1 mounted on the two jigs. Adjust timing. Specifically, the control device 210 turns off the switch unit 202 of the constant power discharge device 200 connected to the

batteries

1 and 1 whose discharge ends at a predetermined time TM (100 seconds), and discharges at that timing. The switch unit 202 of the constant power discharge device 200 connected to the

batteries

1 and 1 to start the operation is turned on.

As described above, when the control device 210 starts constant power discharge for a plurality (50 pieces) of

batteries

1 and 1 mounted on two jigs every predetermined time TM (100 seconds), The number of

batteries

1 and 1 being increased increases by 50. Then, after a while (after 40 minutes have elapsed from the start of the discharge process), in the discharge process, a plurality (1200) of

batteries

1, 1 mounted on 48 jigs are always discharged.

In particular, in this embodiment, since the discharge process and the aging process are operated for 24 hours, after a lapse of 40 minutes from the start of the discharge process, a constant number (1,200) of

batteries

1 and 1 are always discharged in the discharge process. In the aging process, the temperature adjustment device 110 stably uses (consumes) the electric energy derived from the

batteries

1 and 1.

Next, a charge adjustment step is performed on the battery 1 that has been discharged. This charge adjustment step is a step in which the battery 1 is charged and adjusted to a predetermined state of charge (SOC). The charging adjustment process is started at predetermined intervals (50 seconds) for a plurality (25) of

batteries

1 and 1 mounted on one jig described above.

First, a power supply (not shown) is connected to each of the

batteries

1 and 1, respectively. In addition, the power supply device of this embodiment has a plurality of electrode terminal portions in which a positive electrode terminal and a negative electrode terminal are paired, and each

battery

1, 1 connected to each electrode terminal portion through the plurality of electrode terminal portions. Can be charged individually.

Next, the

batteries

1 and 1 are charged with a constant current-constant voltage for 60 minutes. That is, the battery 1 is charged with a constant current until the inter-terminal voltage BV of the battery 1 reaches a predetermined voltage. Thereafter, charging is continued while the inter-terminal voltage BV is maintained at a predetermined voltage. At this time, the charging current gradually decreases. Thus, the battery 1 is brought into a predetermined state of charge (SOC). Then, the power supply terminal part (a positive electrode terminal and a negative electrode terminal) of a power supply device is removed from the battery 1 on a jig | tool.

Next, an internal resistance inspection process is performed on the battery 1 that has been subjected to the charge adjustment process. In this internal resistance inspection step, the DC resistance of the battery 1 is measured for each of the

batteries

1 and 1 using a power supply device, a voltmeter, and an ammeter (not shown), and the DC resistance of each of the

batteries

1 and 1 is not more than a predetermined value. This is a step of inspecting that there is. The direct current resistance of each of the

batteries

1 and 1 was measured using a known direct current resistance measurement method (DC-IR method).

If there is no problem with the battery 1 in this internal resistance inspection process, the battery 1 is shipped.

As mentioned above, in the manufacturing method of the battery 1 according to the present embodiment, all of the electric energy extracted from the battery 1 in the discharging process is used for the electric energy for driving the temperature control device 110 (first heater 111). For this reason, consumption of electric energy can be suppressed as a whole by using the electric energy derived from the battery 1 in the temperature control device 110, and the energy can be used efficiently.

In addition, the discharging process is started for each battery group (that is, for two jigs) composed of the same number (50) of

batteries

1 and 1, respectively, every predetermined time TM (100 seconds), and Timing is adjusted so that the end of discharge in the discharge process of one battery group and the start timing of discharge in the discharge process of another battery group coincide. For this reason, in this discharge process, it is possible to always discharge a certain number (1,200) of the

batteries

1 and 1. Therefore, the electric energy can be stably sent from the

batteries

1 and 1 being discharged in the discharging process to the temperature adjustment device 110 (first heater 111), and the adjustment of the supply destination of the electric energy consumed in the temperature-controlled room 100 is easy. become.

In addition, since the battery 1 is discharged by constant power discharge in the discharge process, constant power per unit time can always be obtained from the

batteries

1 and 1 discharged in the discharge process. Therefore, there is no fluctuation in the electric power supplied from the discharged

batteries

1 and 1, and the adjustment of the supply destination of the electric energy consumed in the temperature-controlled room 100 is further facilitated.

As mentioned above, although this invention was demonstrated according to embodiment, it cannot be overemphasized that this invention is not limited to the said embodiment, It can change and apply suitably in the range which does not deviate from the summary.

For example, in the embodiment, the battery was discharged for 40 minutes in the discharging step, and the battery was charged for 60 minutes in the charging adjustment step. However, for example, discharging over a time other than 40 minutes or charging over a time other than 60 minutes may be performed. Further, the discharge time in the discharge process and the charge time in the charge adjustment process may be the same time.

In the battery manufacturing method of the embodiment, the charge adjustment step is performed after the discharge step. For example, the discharge step may be performed or only the discharge step may be performed after the charge adjustment step.

Moreover, although each process was performed using the jig | tool which mounts the 25

batteries

1 and 1, for example, even if it uses the jig | tool which can mount

several batteries

1 and 1 other than a battery single item, 25 pieces, etc. good. Furthermore, in the embodiment, two jigs are used as one set and the discharging process is performed simultaneously. However, the discharging process may be performed using one jig or a combination of three or more jigs. Moreover, although constant power discharge was performed in the discharge process, for example, constant current discharge may be used.

1 battery 100 constant temperature room 110 temperature control device TM predetermined time

Claims

An aging process in which a battery is accommodated in a temperature-controlled room that maintains a constant room temperature using a temperature control device driven by electric energy, and the battery is subjected to an aging treatment;
A discharge process for discharging the battery, and a method for producing a battery comprising:
The discharging step is
A method for producing a battery, wherein at least a part of the electric energy taken out from the discharged battery is used as at least a part of the electric energy for driving the temperature control device in the aging process for another battery.
A battery manufacturing method according to claim 1, comprising:
The discharging step includes
The discharge process for battery groups each comprising the same number of batteries is initiated at predetermined time intervals; and
A battery manufacturing method in which timing is adjusted so that the end of discharge in the discharge step of one battery group coincides with the start timing of discharge in the discharge step of another battery group.