JP2006253027A - Method for manufacturing secondary battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a secondary battery precisely determining the quality of electric characteristics in the secondary battery. <P>SOLUTION: An average value ΔVam is calculated for a voltage difference ΔV between a first voltage V1 across terminals and a second voltage V2 across terminals for each group of batteries (step SA1). Standard deviation σmΔV of the voltage difference ΔV is calculated (step SA2). It is determined that the secondary battery, where the absolute value of the difference between the voltage difference ΔV and the average value ΔVam exceeds a value obtained by multiplying the value of the standard deviation σmΔV by a prescribed value (n), has poor quality in the secondary batteries belonging to the group of batteries (step SA3). A loop determination process is provided. In the loop determination process, a determination cycle for performing the processes SA1-SA3 is newly repeated by a regulated number of times to other secondary batteries except one having poor quality in the secondary batteries belonging to the group of batteries. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a secondary battery, and more particularly, to a method for manufacturing a secondary battery including a determination step for determining the quality of the electrical characteristics of the secondary battery.

  In recent years, with the development of mobile devices such as mobile phones and mobile personal computers, and the practical application of electric vehicles and hybrid vehicles, demand for secondary batteries such as nickel metal hydride batteries and lithium ion batteries is increasing. Secondary batteries are shipped after the initial assembly process, charging / discharging process, aging process, etc. after the battery is assembled. I try not to ship batteries. (For example, see Patent Document 1, Patent Document 2, and Patent Document 3).

JP 2001-228224 A Japanese Patent Laid-Open No. 2001-266956 Japanese Patent Laid-Open No. 2004-13276

  In Patent Document 1, the voltage between terminals before and after aging is measured for each battery, and a battery whose terminal voltage after aging is lower than the lower limit standard value determined for each battery manufacturing unit is determined as a defective product. Moreover, the average value of the voltage between terminals is calculated | required about the battery whose voltage between terminals is more than a reference standard value, and it is considered as a pass product about the battery whose voltage between terminals is more than the value which deducted the predetermined deviation from this average value. On the other hand, for a battery whose voltage between terminals is less than a value obtained by subtracting a predetermined deviation from this average value, the difference in voltage between terminals before and after aging is obtained, and the voltage difference between terminals is a predetermined deviation from the average value. A battery that is less than the value obtained by subtracting is determined as a defective product.

  In Patent Document 2, the electrical property value before and after aging is measured for each battery, and the difference between the electrical property values before and after aging is obtained. Next, the decay rate or increase rate of the electrical property value is obtained as a function of the difference between the electrical property values, and the battery is screened based on this. Specifically, for example, the voltage between terminals and the internal resistance before and after aging are measured, and the voltage drop rate and the internal resistance increase rate are calculated based on the voltage difference between terminals and the internal resistance difference. Next, calculate the sigma value (standard deviation) from the variation of the voltage drop rate and the internal resistance rise rate using a statistical method, and calculate the sigma value (standard deviation of the voltage drop rate) by 3 times from the average value of the voltage drop rate. The value obtained by subtracting this value is set as the lower limit value, and batteries that fall below the lower limit value are selected as defective. Further, a value obtained by adding three times the sigma value (standard deviation of the internal resistance increase rate) from the average value of the internal resistance increase rate is set as the upper limit value, and a battery exceeding the upper limit value is selected as defective.

  In Patent Document 3, first, the terminal voltage difference ΔV between the terminal voltage V1 before aging and the terminal voltage V2 after aging is calculated, and the average value ΔVA of ΔV is calculated for each lot of inspection. To do. Further, a reference value ΔVB that assumes a voltage drop between terminals of a defective battery that has been internally short-circuited is set in advance as an absolute value. Next, a battery having a value of ΔV smaller than the value of ΔVA−ΔVB is determined as a defective product.

  However, in the methods of Patent Documents 1 and 2, the error due to the environmental temperature at the time of measuring the voltage between the terminals and the error due to the variation between lots of battery materials and processes, etc. are large, and the inspection accuracy cannot be increased. That is, a non-defective battery may be included in a battery determined to be defective, or conversely, a defective product may be included in a battery determined to be non-defective. Further, in the method of Patent Document 3, although the accuracy of identifying defects due to a minute internal short circuit or the like is improved as compared with the methods of Patent Documents 1 and 2, an error due to the environmental temperature at the time of measuring the voltage between terminals, Sufficient judgment accuracy could not be obtained due to the effect of errors due to variations between lots of battery materials and processes.

  This invention is made | formed in view of this present condition, Comprising: It aims at providing the manufacturing method of a secondary battery which can determine the quality of the electrical property of a secondary battery accurately.

  The solution means that, for each battery group including a predetermined number of secondary batteries as a set, for each secondary battery belonging to the battery group, a first inter-terminal voltage V1 that is a voltage between the terminals is measured. After the voltage measurement step and the first voltage measurement step, for each battery group, for each secondary battery belonging to the battery group, a second voltage for measuring a second inter-terminal voltage V2 that is a voltage between the terminals. For each secondary battery belonging to the battery group for each battery group, the electrical characteristics of the secondary battery are determined based on the first inter-terminal voltage V1 and the second inter-terminal voltage V2. A determination step of determining a secondary battery, wherein the first voltage measurement step and the second voltage measurement step are both placed in a high temperature atmosphere for a predetermined period. Or the first voltage measurement step is provided before the aging step, the second voltage measurement step is provided after the aging step, and the determination step is performed for each battery group. Any electrical characteristic value selected from three electrical characteristic values: terminal voltage V1, second terminal voltage V2, and voltage difference ΔV between first terminal voltage V1 and second terminal voltage V2. For the secondary battery belonging to the battery group, the absolute value of the difference between the electrical characteristic value and the average value is calculated as the average value and the standard deviation of the selected electrical characteristic value. Other secondary batteries excluding the secondary battery determined to be defective among the secondary batteries belonging to the battery group after determining that the secondary battery exceeding the value obtained by multiplying the standard deviation value by the predetermined value n as defective About again Calculating an average value of the electrical characteristic values, and calculating a standard deviation of the electrical characteristic values, and among the secondary batteries, an absolute value of a difference between the electrical characteristic value and the average value is the standard deviation. This is a method of manufacturing a secondary battery including a loop determination step in which a determination cycle for determining a secondary battery exceeding the value obtained by multiplying the above value by the predetermined value n as defective is repeated a plurality of times.

  In the manufacturing method of the present invention, a statistical deviation is obtained by using a standard deviation of one of the electrical characteristic values selected from the three electrical characteristic values of the first terminal voltage V1, the second terminal voltage V2, and the voltage difference ΔV. In particular, there is provided a loop determination step in which a determination cycle for determining defective electrical characteristics is repeated a plurality of times. As described above, by repeating the determination cycle using the standard deviation a plurality of times, it is possible to improve the accuracy of determining the quality of the secondary battery. That is, as the determination cycle is repeated, the secondary battery whose electrical characteristic value is significantly different from the average value is excluded, and the variation in the electrical characteristic value of the secondary battery to be determined can be reduced. For this reason, finally, it is possible to perform pass / fail determination using the standard deviation for a group of secondary batteries with small variations in electrical characteristic values, so that the determination accuracy can be improved. Therefore, according to the manufacturing method of the present invention, the quality of the secondary battery can be accurately determined.

  In the loop determination step, for example, one electrical characteristic value (for example, voltage difference ΔV) selected from the three electrical characteristic values of the first terminal voltage V1, the second terminal voltage V2, and the voltage difference ΔV is used. It can be carried out. Further, after one electrical characteristic value (for example, the first terminal voltage V1) is selected from the three electrical characteristic values and the loop determination step is performed, another electrical characteristic value (for example, the second terminal voltage V2) is selected. ) May be selected to perform the loop determination step.

Moreover, as a method of determining the defect of the secondary battery based on the first terminal voltage V1 and the second terminal voltage V2, for example, the respective values of the first terminal voltage V1 and the second terminal voltage V2 The method of judging by is mentioned. Specifically, for example, a secondary battery in which the first terminal voltage V1 is out of the appropriate range of the preset first terminal voltage V1 is determined to be defective, and the second terminal voltage V2 is This is a method of determining a secondary battery that is out of the appropriate range of the preset second terminal voltage V2 as defective.
Further, the secondary battery is defective due to the value of the voltage difference ΔV between the first terminal voltage V1 and the second terminal voltage V2 (corresponding to the value based on the first terminal voltage V1 and the second terminal voltage V2). A method for determining the above may be used. Specifically, for example, a secondary battery in which the voltage difference ΔV is outside the appropriate range of the preset voltage difference ΔV is determined to be defective.

  Furthermore, in the above method for manufacturing a secondary battery, the loop determination step may be a method for manufacturing a secondary battery that performs the determination cycle for the voltage difference ΔV.

  Since the minute internal short circuit of the secondary battery is promoted by placing the secondary battery in a high temperature atmosphere, aging occurs between the battery in which the minute internal short circuit occurs and the battery in which the minute internal short circuit does not occur (almost never occurs). As the process proceeds, the voltage difference ΔV between the terminals increases greatly. For this reason, if the quality of the secondary battery is judged based on the voltage difference ΔV, the difference between the battery in which a minute internal short circuit has occurred and the battery in which it has not occurred (almost never occurs) becomes clear. Accuracy can be increased. Therefore, according to the manufacturing method of the present invention, the quality of the secondary battery can be determined with high accuracy.

  Furthermore, in any one of the above secondary battery manufacturing methods, both the first voltage measuring step and the second voltage measuring step may be a secondary battery manufacturing method provided in the aging step.

  In the conventional secondary battery manufacturing method, the first voltage measurement step is provided before the aging step, and the second voltage measurement step is provided after the aging step. However, since the secondary battery is placed in a high-temperature atmosphere for a predetermined period in the aging process, the temperature of the secondary battery greatly increases. Therefore, in order to measure the voltage between the terminals under the same conditions before and after the aging process, after waiting for the temperature of the secondary battery to drop to the temperature before the aging process after the aging process, The voltage V2 between the second terminals could not be measured.

  On the other hand, in the manufacturing method of the secondary battery of this invention, both the 1st voltage measurement process and the 2nd voltage measurement process are provided in the aging process. For this reason, in both the first voltage measurement step and the second voltage measurement step, it is possible to measure the inter-terminal voltage while the temperature of the secondary battery is stable at a high temperature. Therefore, unlike the conventional method, the second inter-terminal voltage V2 can be measured without waiting for the temperature of the secondary battery to drop to the temperature before the aging process after the aging process. Moreover, since both the first voltage measurement process and the second voltage measurement process can be completed during the aging process, the process time can be greatly shortened, and the productivity of the secondary battery can be increased.

  Furthermore, in the method for manufacturing a secondary battery described above, a method for manufacturing the secondary battery in which the first voltage measurement step is performed after the temperature of the secondary battery is stabilized at a predetermined temperature in the aging step. Good.

  Since the temperature of the secondary battery continues to rise for a while after starting the aging process, it is not stable. On the other hand, in the method for manufacturing a secondary battery of the present invention, the voltage V1 between the first terminals is measured after the temperature of the secondary battery is stabilized at a predetermined temperature in the aging process. As a result, both the voltage V1 between the first terminals and the voltage V2 between the second terminals can be measured in a state where the temperature of the secondary battery is stable at a predetermined temperature, so that the reliability of the measured values V1 and V2 is improved. As a result, the accuracy of the quality determination of the secondary battery can be increased.

  Furthermore, in any of the above secondary battery manufacturing methods, the battery group includes a charge / discharge step of charging / discharging the secondary battery before the aging step and the first voltage measurement step. In the charging / discharging process, a method for manufacturing a secondary battery that is a set of a predetermined number of secondary batteries that are simultaneously charged and discharged by the same charging / discharging device may be used.

  The voltage between the terminals of the secondary battery is slightly different due to the influence of the time from charging / discharging to measuring the voltage, the charging / discharging environment (temperature, humidity, etc.) and the like. For this reason, when judging the quality of secondary batteries for battery groups in which secondary batteries that have been charged / discharged at different timings or secondary batteries that have been charged / discharged by different charge / discharge devices are mixed. Since the variation in the voltage between terminals of each secondary battery which belongs to a battery group becomes large, there exists a possibility that determination accuracy may fall.

  On the other hand, in the manufacturing method of the present invention, the first voltage measuring step, the second voltage, and the like, in which a set of a predetermined number of secondary batteries that are simultaneously charged and discharged by the same charging / discharging device are set as one battery group. A measurement process and a determination process are performed, and the quality of the secondary battery is determined. In a battery group that has been charged and discharged simultaneously by the same charging / discharging device, variation in the voltage between terminals of each secondary battery belonging to the battery group is reduced. Therefore, for each battery group, the first voltage measurement step, The determination accuracy can be improved by performing the two voltage measurement process and the determination process.

  Another solution is to measure a first inter-terminal voltage V1 which is a voltage between terminals of each secondary battery belonging to the battery group for each battery group including a predetermined number of secondary batteries as a set. After the first voltage measurement step and the first voltage measurement step, a second voltage V2 that is a voltage between the terminals of each secondary battery belonging to the battery group is measured for each battery group. For each secondary battery belonging to the battery group for each battery group, a voltage measurement step is performed on the basis of the voltage V1 between the first terminals and the voltage V2 between the second terminals. A determination process for determining pass / fail, wherein the first voltage measurement process and the second voltage measurement process are both placed in a high temperature atmosphere for a predetermined period of time. Do A method of manufacturing a secondary battery including in Jingu process.

  In the conventional secondary battery manufacturing method, the first voltage measurement step is provided before the aging step, and the second voltage measurement step is provided after the aging step. However, since the secondary battery is placed in a high-temperature atmosphere for a predetermined period in the aging process, the temperature of the secondary battery greatly increases. Therefore, in order to measure the voltage between the terminals under the same conditions before and after the aging process, after waiting for the temperature of the secondary battery to drop to the temperature before the aging process after the aging process, The voltage V2 between the second terminals could not be measured.

  On the other hand, in the manufacturing method of the secondary battery of this invention, both the 1st voltage measurement process and the 2nd voltage measurement process are provided in the aging process. For this reason, in both the first voltage measurement step and the second voltage measurement step, it is possible to measure the inter-terminal voltage while the temperature of the secondary battery is stable at a high temperature. Therefore, unlike the conventional method, the second inter-terminal voltage V2 can be measured without waiting for the temperature of the secondary battery to drop to the temperature before the aging process after the aging process. Moreover, since both the first voltage measurement process and the second voltage measurement process can be completed during the aging process, the process time can be greatly shortened, and the productivity of the secondary battery can be increased.

  In addition, as a method of determining the defect of the secondary battery based on the voltage V1 between the first terminals and the voltage V2 between the second terminals, for example, each value of the voltage V1 between the first terminals and the voltage V2 between the second terminals The method of judging by is mentioned. Further, the secondary battery is defective due to the value of the voltage difference ΔV between the first terminal voltage V1 and the second terminal voltage V2 (corresponding to the value based on the first terminal voltage V1 and the second terminal voltage V2). A method for determining the above may be used.

  Furthermore, in the method for manufacturing a secondary battery described above, a method for manufacturing the secondary battery in which the first voltage measurement step is performed after the temperature of the secondary battery is stabilized at a predetermined temperature in the aging step. Good.

  Since the temperature of the secondary battery continues to rise for a while after starting the aging process, it is not stable. On the other hand, in the method for manufacturing a secondary battery of the present invention, the voltage V1 between the first terminals is measured after the temperature of the secondary battery is stabilized at a predetermined temperature in the aging process. As a result, both the voltage V1 between the first terminals and the voltage V2 between the second terminals can be measured in a state where the temperature of the secondary battery is stable at a predetermined temperature, so that the reliability of the measured values V1 and V2 is improved. As a result, the accuracy of the quality determination of the secondary battery can be increased.

(Embodiment)
1 is a front view of a secondary battery 100 according to the present embodiment, FIG. 2 is a side view thereof, and FIG. 3 is a cross-sectional view thereof (corresponding to a cross-sectional view taken along line AA in FIG. 2).
The secondary battery 100 according to the present embodiment includes a battery case 110 made of metal (specifically, a nickel-plated steel plate), a safety valve device 113, and an electrode plate group 120 disposed in the battery case 110 (FIG. 3). And a sealed nickel-metal hydride storage battery including an electrolyte solution (not shown).

  As shown in FIG. 3, the electrode plate group 120 includes a plurality of positive electrode plates 121 having positive electrode active material layers 121 s and a plurality of negative electrode plates 123 having negative electrode active material layers 123 s stacked alternately via separators 125. Is configured. Of the negative electrode plate 123, the negative electrode lead portion 123r in which the negative electrode active material layer 123s is not formed extends in a predetermined direction (left side in FIG. 3). On the other hand, in the positive electrode plate 121, the positive electrode lead portion 121r in which the positive electrode active material layer 121s is not formed extends in the opposite direction (right side in FIG. 3) to the negative electrode lead portion 123r.

  As the positive electrode plate 121, for example, an electrode plate in which an active material support made of foamed nickel is supported with an active material containing nickel hydroxide (forming the positive electrode active material layer 121s) can be used. As the negative electrode plate 123, for example, an electrode plate in which an active material containing a hydrogen storage alloy or the like (forming the negative electrode active material layer 123s) is supported on an electrode support can be used. Moreover, as the separator 125, the nonwoven fabric which consists of a synthetic fiber by which the hydrophilic treatment was carried out can be used, for example. As the electrolytic solution, for example, an alkaline aqueous solution having a specific gravity of 1.2 to 1.4 containing KOH as a main component can be used.

  As shown in FIG. 3, the battery case 110 is made of a metal (specifically, a nickel-plated steel plate), a battery case 111 having a rectangular box shape, and a metal (specifically, a nickel-plated steel plate). And a sealing member 115 having a substantially rectangular plate shape. Among these, two through holes 111 h are formed in the third side wall 111 e of the battery case 111. A first positive terminal 140b and a second positive terminal 140c are inserted into the two through holes 111h with an electrically insulating seal member 145 interposed therebetween. The sealing member 115 is welded all around in a state where the sealing member 115 is in contact with the opening end surface 111f of the battery case 111 (see FIG. 3), and seals the opening 111g of the battery case 111. Thereby, the sealing member 115 and the battery case 111 are integrated to form the battery case 110.

  As shown in FIG. 3, each of the negative electrode lead portions 123r of the negative electrode plate 123 is joined to the inner side surface 115b of the sealing member 115 by electron beam welding or the like. Thereby, in the secondary battery 100 of this embodiment, the battery case 110 whole including the sealing member 115 becomes a negative electrode. Further, all of the positive electrode lead portions 121r of the positive electrode plate 121 are joined to the inner side surface 130b of the positive electrode current collector plate 130 by electron beam welding or the like. Furthermore, the positive electrode current collector plate 130 is joined to the first positive electrode terminal 140b and the second positive electrode terminal 140c by laser welding or the like. Thereby, the 1st positive electrode terminal 140b and the 2nd positive electrode terminal 140c, and the positive electrode plate 121 are electrically connected.

Next, a method for manufacturing the secondary battery 100 of the present embodiment will be described below.
(Assembly process)
First, the positive electrode plate 121 and the negative electrode plate 123 are alternately laminated while the separator 125 is interposed between the positive electrode plate 121 and the negative electrode plate 123 to form the electrode plate group 120. Next, the negative electrode lead portion 123r of the negative electrode plate 123 in the electrode plate group 120 is joined to the inner surface 115b side of the sealing member 115 by electron beam welding. Further, the positive electrode lead portion 121r of the positive electrode plate 121 is joined to the inner side surface 130b side of the positive electrode current collector plate 130 by electron beam welding.

  Separately, the first positive terminal 140 b and the second positive terminal 140 c are fixed to the battery case 111. Specifically, the seal member 145 is attached to the through hole 111h of the battery case 111, and the pole column portions 141 of the first positive terminal 140b and the second positive terminal 140c are inserted from the outside. Next, fluid pressure is applied to the inside of the pole column portion 141 to bulge one end side of the pole column portion 141 radially outward and further compressively deform in the axial direction to form a compression deformed portion 141h. Accordingly, the first positive terminal 140b and the second positive terminal 140c are fixed to the battery case 111 while being electrically insulated from the battery case 111.

  Next, among the joined body formed by joining the electrode plate group 120, the sealing member 115, and the positive electrode current collector plate 130, the positive electrode current collector plate 130 and the electrode plate group 120 are inserted into the battery case 111 from the opening 111g. At the same time, the battery case 111 is covered with the sealing member 115. Next, laser is irradiated from the outside, the sealing member 115 and the battery case 111 are joined, and the battery case 111 is sealed. Next, the laser is irradiated from the outside of the first positive electrode terminal 140b and the second positive electrode terminal 140c toward the depression of the pole column portion 141, and the compression deformation portion 141h of the pole column portion 141 and the positive electrode current collector plate 130 are joined. . Next, an electrolyte is injected from an inlet 111k located in the ceiling 111a of the battery case 111, and a safety valve 113 is attached so as to close the inlet 111k.

(Battery placement process)
Next, the plurality of secondary batteries 100 assembled as described above are arranged and fixed on a limiting jig 200 as shown in FIG.
Here, the limiting jig 200 according to the present embodiment will be described. As shown in FIG. 4, the limiting jig 200 includes substantially rectangular plate-like side plates 210 and 220, four connecting rods 230 having a regular hexagonal cross section, eight fastening bolts 240, and both side plates 210 and 220. And a plurality of expansion limiting members 250 and 260 located between the two. The side plate 210 and the side plate 220 are connected by four connecting rods 230 fixed by fastening bolts 240 at the respective corners.

  The expansion limiting member 250 is made of an electrically insulating resin, and as shown in FIGS. 4 (a) and 4 (b), a side wall portion 251 that is substantially E-shaped when viewed from above and extends in a direction perpendicular to the paper surface, and a rectangular plate shape And a bottom portion 252 of the main body. The expansion limiting member 260 is made of an electrically insulating resin and has a substantially flat plate shape as shown in FIGS. 4 (a) and 4 (b). In the present embodiment, the expansion limiting member 260 and the 50 expansion limiting members 250 are arranged in a line between the side plate 210 and the side plate 220 with a gap therebetween. Thereby, 100 battery accommodating parts S are formed in the limiting jig 200 of this embodiment.

  The expansion limiting member 250 is formed with through holes 254 that extend in the direction in which the expansion limiting members 250 are arranged (left and right in FIGS. 4A and 4B). Therefore, as shown in FIG. 4B, when the expansion limiting member 250 is disposed at a predetermined position, the through holes 254 of the respective expansion limiting members 250 are arranged in a line on the same axis. Further, the expansion limiting member 260 is also provided with a through hole 264 at a position aligned with the through hole 254 of the expansion limiting member 250 on the same axis line when arranged at a predetermined position. Furthermore, a through hole 214 and a through hole 224 are drilled in the side plate 210 and the side plate 220, respectively, at positions aligned on the same axis as the through hole 254 of the expansion limiting member 250 arranged at a predetermined position. .

  Furthermore, in the limiting jig 200, one insertion rod 272 is arranged on the same axis, the through hole 214 of the side plate 210, the through hole 264 of the expansion limiting member 260, the through hole 254 of the expansion limiting member 250, The through hole 224 of the side plate 220 is inserted and fixed to the side plates 210 and 220. Thereby, the expansion limiting member 260 and the 50 expansion limiting members 250 are movable between the side plate 210 and the side plate 220 in the direction in which the insertion rod 272 extends (left and right in FIG. 4A), Fixed.

  In the battery arrangement process of the present embodiment, first, 100 secondary batteries 100 are inserted and arranged in the battery accommodating portion S (see FIG. 4) of the limiting jig 200. Next, by fastening the fastening bolt 240, the gap between the side plate 210 and the side plate 220 is reduced, and the first side wall portion 111c and the second side wall portion 111d of the secondary battery 100 and the expansion limiting members 250 and 260 are brought into close contact with each other. . As a result, as shown in FIG. 5, 100 secondary batteries 100 can be fixed to the limiting jig 100 while being electrically insulated from each other.

  By the way, generally, when a secondary battery is charged or the battery temperature is increased, the internal pressure tends to expand due to an increase in internal pressure. In particular, in the secondary battery 100 of the present embodiment, the first side wall part 111c and the second side wall part 111d having the largest outer surface area in the battery case 111 tend to expand most. On the other hand, in this embodiment, as described above, by placing and fixing 100 secondary batteries 100 on the limiting jig 100, the expansion of each secondary battery 100 (battery case 110) is the most. It can restrict about the 1st side wall part 111c and the 2nd side wall part 111d which tend to expand. For this reason, expansion of the secondary battery 100 (battery case 110) can be appropriately suppressed in an initial charging process, a charging / discharging process, and an aging process described later.

  Note that, as shown in FIG. 4B, openings 256 are formed at positions on both sides of the expansion limiting member 250 of the limiting jig 200. As a result, when the secondary battery 100 is inserted and arranged in the battery housing portion S (see FIG. 4) of the limiting jig 200, as shown in FIG. The three side wall portions 111e (negative electrode) and the first and second positive electrode terminals 140b and 140c can be exposed to the outside. Therefore, in the initial charging step, the charging / discharging step, the first voltage measuring step, and the second voltage measuring step, which will be described later, the positive electrode terminal and the negative electrode terminal of each device can be easily set from the side of the secondary battery 100. In addition, the third side wall portion 111e (negative electrode) and the first and second positive electrode terminals 140b and 140c can be connected.

(Initial charging process)
Next, the limiting jig 200 (see FIG. 5) in which the secondary battery 100 is disposed is attached to an initial charging device (not shown), and the secondary battery 100 is disposed in the state in which the secondary battery 100 is disposed in the limiting jig 200. The initial charge was applied. Specifically, after the limiting jig 200 in which the secondary battery 100 is arranged is attached to the initial charging device, the negative electrode terminal of the initial charging device (not shown) is connected to the side of the secondary battery 100 (FIG. 5A). Are connected to the third side wall 111e (negative electrode) of the secondary battery 100 from above and below. At the same time, the positive terminal of the initial charging device (not shown) is connected to the second positive terminal 140c of the secondary battery 100 from the side of the secondary battery 100 (upper and lower in FIG. 5A).

Next, using a power supply device (not shown), each secondary battery 100 was charged to a SOC (State Of Charge) of 20 to 50% with a current of 0.1 C. Thereafter, the battery was further charged to 100% SOC at a current of 0.5C. In the present embodiment, 1C = 6.5A and SOC 100% = 6.5Ah. Thereafter, the limiting jig 200 was removed from the initial charging device while the secondary battery 100 was placed.
By the way, in the initial charging step of the present embodiment, as described above, the secondary battery 100 is arranged and fixed on the limiting jig 200 (specifically, the expansion of the battery case 110 tends to expand most). Initial charging is performed in a state where the first side wall 111c and the second side wall 111d are limited. For this reason, the expansion of the battery case 111 at the time of initial charge can be appropriately suppressed, and the distortion of the battery case 110 and the leakage of the electrolyte solution can be prevented.

(Charge / discharge process)
Next, the secondary battery 100 was mounted on a charging / discharging device (not shown) while being placed on the limiting jig 200, and the secondary battery 100 was charged / discharged. Specifically, first, after the restriction jig 200 in which 100 secondary batteries 100 are arranged is removed from the initial charging device, the 100 secondary batteries 100 are placed in the restriction jig 200, Attached to a charge / discharge device. Next, the negative electrode terminal of the charging / discharging device (not shown) is connected to the third side wall portion 111e (negative electrode) of the secondary battery 100 from the side of the secondary battery 100 (upper and lower in FIG. 5A). Let At the same time, the positive electrode terminal of the charging / discharging device (not shown) is connected to the first and second positive electrode terminals 140b and 140c of the secondary battery 100 from the side of the secondary battery 100 (above and below in FIG. 5A). , Connect them respectively.

Next, each secondary battery 100 was repeatedly charged and discharged using a power supply device (not shown). Specifically, a charge / discharge cycle of charging to SOC 100% with a current of 2 to 5C and then discharging until the battery voltage became 1.0V with a current of 5C was repeated several tens of cycles. Thereafter, the limiting jig 200 was removed from the charging / discharging device while the secondary battery 100 was disposed.
By the way, in the charging / discharging process of the present embodiment, as described above, the secondary battery 100 is arranged and fixed on the limiting jig 200 (specifically, the expansion of the battery case 110 tends to expand most). Charging / discharging is performed in a state where the first side wall 111c and the second side wall 111d are limited. For this reason, expansion of the battery case 111 at the time of charging / discharging can be suppressed appropriately, and distortion of the battery case 110, leakage of the electrolyte, and the like can be prevented.

(Aging process)
Next, it progressed to the aging process and the secondary battery 100 which performed charging / discharging was arrange | positioned in the aging apparatus 500 shown in FIG. Specifically, after the restriction jig 200 in which 100 secondary batteries 100 are arranged is removed from the charging / discharging device, 100 secondary batteries 100 are arranged in the restriction jig 200 as shown in FIG. As it was, it was placed in an aging device 500 maintained in a high temperature atmosphere at a substantially constant temperature within a range of 35-60 ° C., and placed for 5-10 days.

  As shown in FIG. 6, the aging device 500 of the present embodiment includes a conveyor 510 that extends from the inlet 501 to the outlet 502 of the aging device 500. The conveyor 510 slowly conveys the limiting jig 200 on which the secondary battery 100 is arranged from the inlet 501 to the outlet 502 of the aging device 500 over 5 to 10 days. Therefore, when the limiting jig 200 in which 100 secondary batteries 100 are arranged is placed on the conveyor 510 from the inlet 501, it is carried out from the outlet 502 after five to ten days. That is, the secondary battery 100 is placed in the aging apparatus 500 held in a high-temperature atmosphere at a substantially constant temperature in the range of 35 to 60 ° C. for 5 to 10 days while being placed in the limiting jig 200. Will be.

  Furthermore, the aging device 500 of this embodiment includes a first voltage measurement device (not shown) at the first voltage measurement position C1 (see FIG. 6). Thereby, when the limiting jig 200 in which 100 secondary batteries 100 are arranged is conveyed by the conveyor 510 and reaches the first voltage measurement position C1, the terminal of each secondary battery 100 is received by the first voltage measurement device. The first inter-terminal voltage V1 that is an inter-voltage can be measured. Specifically, from the side of the secondary battery 100 (the front side and the back side in FIG. 6), the negative electrode terminal of the first voltage measuring device (not shown) is connected to the third side wall portion 111e ( In addition, the positive terminal of the first voltage measuring device (not shown) is connected to the second positive terminal 140c of each secondary battery 100, and the first inter-terminal voltage V1 is measured.

  Furthermore, the aging device 500 of this embodiment includes a second voltage measurement device (not shown) at the second voltage measurement position C2 (see FIG. 6). Thereby, when the limiting jig 200 in which 100 secondary batteries 100 are arranged is conveyed by the conveyor 510 and reaches the second voltage measurement position C2, the terminal of each secondary battery 100 is obtained by the second voltage measurement device. The voltage V2 between the 2nd terminals which is an inter-voltage can be measured. Specifically, from the side of the secondary battery 100 (the front side and the back side in FIG. 6), the negative electrode terminal of the second voltage measuring device (not shown) is connected to the third side wall portion 111e ( And a positive electrode terminal of a second voltage measuring device (not shown) is connected to the second positive electrode terminal 140c of each secondary battery 100 to measure the voltage V2 between the second terminals.

  In the present embodiment, after 1 to 3 days have elapsed since the limiting jig 200 in which the secondary battery 100 is disposed is placed in the aging device 500 (loaded from the inlet 501), the first jig is measured at the first voltage measurement position C1. For example, after 5 to 10 days have passed, the second voltage measurement position C2 is adjusted. Therefore, the first terminal voltage V1 can be measured for each of the 100 secondary batteries 100 placed in the aging device 500 (in a high temperature atmosphere of about 40 ° C.) for 1 to 3 days. Further, the second inter-terminal voltage V2 can be measured for each of the 100 secondary batteries 100 placed in the aging device 500 (in a high temperature atmosphere of about 40 ° C.) for 5 to 10 days, for example.

  Furthermore, in this embodiment, for each group of 100 secondary batteries 100 arranged in the limiting jig 200, the secondary battery 100 of the secondary battery 100 is based on the first terminal voltage V1 and the second terminal voltage V2. Judge the quality of electrical characteristics, and discriminate between good and defective products. Here, flowcharts of the first voltage measurement process, the second voltage measurement process, and the determination process according to the present embodiment are shown in FIGS. 7 and 8, and the first voltage measurement process, The voltage measurement process and the determination process will be described in detail. In the present embodiment, step S1 corresponds to the first voltage measurement process, step S3 corresponds to the second voltage measurement process, and steps S2 and S4 to SD correspond to the determination process.

  First, when the limiting jig 200 in which 100 secondary batteries 100 are arranged reaches the first voltage measurement position C1, as shown in FIG. 7, in step S1, about 100 secondary batteries 100, respectively. The first terminal voltage V1 is measured. Subsequently, it progresses to step S2 and it is determined about each of the 100 secondary batteries 100 whether the measured 1st terminal voltage V1 exists in an appropriate range. Specifically, whether or not the measured first terminal voltage V1 is a value between a preset lower limit value V1min and upper limit value V1max of the first terminal voltage V1 (relationship of V1min <V1 <V1max). Or not) is determined. The secondary battery 100 in which the voltage V1 between the first terminals is not within the above-described appropriate range (NO) is determined as a defective product and excluded from the subsequent determination targets. In this embodiment, V1min = 1.0 (V) and V1max = 1.3 (V) are set.

  After that, when the limiting jig 200 in which 100 secondary batteries 100 are arranged reaches the second voltage measurement position C2, the process proceeds to step S3 and satisfies the relationship V1min <V1 <V1max (YES in step S2). For each of the batteries 100, the second terminal voltage V2 is measured. Subsequently, it progresses to step S4 and it is determined about each of the said secondary batteries 100 whether the measured 2nd terminal voltage V2 exists in an appropriate range. Specifically, whether or not the measured second terminal voltage V2 is a value between a preset lower limit value V2min and upper limit value V2max of the second terminal voltage V2 (relationship of V2min <V2 <V2max). Or not) is determined. Here, the secondary battery 100 (NO) in which the voltage V2 between the second terminals is not a value within the above range is determined as a defective product and excluded from the subsequent determination targets. In the present embodiment, V2min = 1.0 (V) and V2max = 1.3 (V) are set.

  Next, the process proceeds to step S5, and the average value V2a of the second terminal voltage V2 is calculated for the secondary battery 100 that satisfies the relationship of V2min <V2 <V2max (YES in step S4). In step S6, the standard deviation σV2 of the second terminal voltage V2 was calculated for the group of the secondary batteries 100. Subsequently, it progressed to step S7 and the quality of the electrical property of the secondary battery 100 was determined based on average value V2a and standard deviation (sigma) V2. Specifically, for the secondary batteries 100 belonging to the group, the absolute value | V2−V2a | of the difference between the voltage V2 between the second terminals and the average value V2a is a predetermined value n as the value of the standard deviation σV2. It is determined whether or not the value is less than or equal to the multiplied value n (σV2) (whether or not the relationship of | V2−V2a | ≦ n (σV2) is satisfied). Here, the secondary battery 100 (NO) in which the absolute value | V2−V2a | exceeds n (σV2) is determined as a defective product and excluded from the subsequent determination targets. The predetermined value n is set to a value in the range of 3 to 5, for example.

  Next, the process proceeds to step S8, and the secondary battery 100 satisfying the relationship of | V2−V2a | ≦ n (σV2) (YES in step S7), the voltage V1 between the first terminals and the voltage V2 between the second terminals, respectively. The voltage difference ΔV = | V1−V2 | is calculated. Next, the process proceeds to step S9, and it is determined whether or not the calculated voltage difference ΔV is within an appropriate range for each of the secondary batteries 100. Specifically, whether or not the calculated voltage difference ΔV is a value between a lower limit value ΔVmin and an upper limit value ΔVmax of the preset voltage difference ΔV (whether or not the relationship of ΔVmin <ΔV <ΔVmax is satisfied). Determine. Here, the secondary battery 100 (NO) in which the voltage difference ΔV is not a value within the above range is determined as a defective product and excluded from the subsequent determination targets. In this embodiment, ΔVmin = 0 (V) and ΔVmax = 0.2 (V) are set.

Next, the process proceeds to step SA, and loop determination is performed for the secondary battery 100 that satisfies the relationship of ΔVmin <ΔV <ΔVmax (YES in step S9). Specifically, as shown in FIG. 8, the determination cycle of step SA1 to step SA4 was repeated for a preset number of times. In the present embodiment, step SA corresponds to a loop determination process.
First, in step SA1, the average value ΔVam of the voltage difference ΔV is calculated for the secondary battery 100 that satisfies the relationship ΔVmin <ΔV <ΔVmax (YES in step S9). Next, the process proceeds to step SA2, and the standard deviation σmΔV of the voltage difference ΔV is calculated for the group of secondary batteries 100.

  Next, the process proceeds to step SA3, and the quality of the electrical characteristics of the secondary battery 100 is determined based on the average value ΔVam and the standard deviation σmΔV. Specifically, for the secondary batteries 100 belonging to the group, the absolute value | ΔV−ΔVam | of the difference between the voltage difference ΔV and the average value ΔVam is a value obtained by multiplying the value of the standard deviation σmΔV by a predetermined value n. It is determined whether or not the value is equal to or less than n (σmΔV) (whether or not the relationship | ΔV−ΔVam | ≦ n (σmΔV) is satisfied). Here, the secondary battery 100 (NO) in which the absolute value | ΔV−ΔVam | exceeds n (σmΔV) is determined as a defective product and excluded from the subsequent determination targets. Note that the predetermined value n is set to a value in the range of 3 to 5, for example, as described above.

Next, the process proceeds to step SA4, and it is determined whether or not the cycle number m of the determination cycle of steps SA1 to SA3 has reached a preset number of rules. If the number of cycles m has not yet reached the prescribed number (NO), the process returns to step SA1 again, and satisfies the relationship | ΔV−ΔVam | ≦ n (σmΔV) in the previous step SA3 (YES). For the determined group of secondary batteries 100, the above-described processing of Step SA1 to Step SA3 is performed again. When the determination cycle is repeated for the specified number of times, it is determined in step SA4 that the cycle number m has reached the specified number of times (YES), the loop determination in step SA is terminated, and the process returns to the main routine of FIG.
In addition, the regulation number of the cycle number m is set to a number within a range of 5 to 10 times, for example.

  Next, the process proceeds to step SB, and in the loop determination at step SA, the relationship | ΔV−ΔVam | ≦ n (σmΔV) is satisfied until the end (YES in step SA3 of the final cycle). An average value ΔVa of ΔV is calculated. Next, the process proceeds to step SC, and a final standard deviation σΔV of ΔV is calculated for the group of secondary batteries 100.

  Next, the process proceeds to step SD, and finally the quality of the electrical characteristics of the secondary battery 100 is determined based on the average value ΔVa and the standard deviation σΔV. Specifically, for the secondary batteries 100 belonging to the group, the absolute value | ΔV−ΔVa | of the difference between the voltage difference ΔV and the average value ΔVa is a value obtained by multiplying the value of the standard deviation σΔV by a predetermined value n. It is determined whether or not the value is equal to or less than n (σΔV) (whether or not the relationship | ΔV−ΔVa | ≦ n (σΔV) is satisfied). Here, the secondary battery 100 (NO) in which the absolute value | ΔV−ΔVa | exceeds n (σΔV) is determined as a defective product. On the contrary, the secondary battery 100 determined to satisfy the relationship of | ΔV−ΔVa | ≦ n (σΔV) (YES) is determined as a non-defective product. Note that the predetermined value n is set to a value in the range of 3 to 5, for example, as described above.

  Next, after the restriction jig 200 in which 100 secondary batteries 100 are arranged is carried out from the outlet 502 of the aging device 500 (see FIG. 6), the 100 secondary batteries 100 are taken out from the restriction jig 200. And about these secondary batteries 100, it discriminate | determines into the secondary battery 100 determined to be inferior goods in the determination process (step S2, S4-SD), and the secondary battery 100 determined to be good goods. Among these, the secondary battery 100 determined to be a non-defective product can be said to have good electrical characteristics, and is shipped after passing through the subsequent steps. On the contrary, the secondary battery 100 determined to be defective is discarded because it has a poor electrical characteristic.

  In the present embodiment, it is preferable to assign, for example, identification numbers of 1 to 100 to the 100 secondary batteries 100 arranged in the limiting jig 200. In this way, in the determination step (steps S2, S4 to SD), the secondary battery 100 determined to be defective and the secondary battery 100 determined to be non-defective can be managed by the identification number. It becomes possible to accurately and quickly discriminate between good and defective products.

  When the secondary battery 100 is manufactured as described above, a non-defective product is included in the secondary battery 100 determined to be defective, and conversely, the secondary battery 100 is determined to be non-defective. There was almost no defective product. That is, by using the manufacturing method of the present embodiment, the accuracy of determining the quality of the secondary battery 100 can be improved. This is thought to be due to the following factors.

  First, in step SA, the determination cycle of step SA1 to step SA4 is repeatedly performed a specified number of times (for example, 5 to 10 times), so that the determination accuracy of the electrical characteristics of the secondary battery 100 can be improved. It is done. Specifically, as the determination cycle of Step SA1 to Step SA4 is repeated, the secondary battery 100 in which the voltage difference ΔV deviates from the average value ΔVam by more than a predetermined value (specifically, n (σmΔV)) can be excluded. Therefore, the variation in the voltage difference ΔV of the secondary battery 100 to be determined can be reduced. Therefore, finally, in step SD, the quality determination using the standard deviation σΔV can be performed for the group of the secondary batteries 100 having a small variation in the voltage difference ΔV, so that the determination accuracy can be improved. It is thought that it was made.

  In step SA, it is considered that the determination accuracy can be improved by performing the determination cycle of steps SA1 to SA4 for the voltage difference ΔV. This is not caused by the secondary battery 100 in which the minute internal short circuit occurs because the minute internal short circuit of the secondary battery 100 is promoted by placing the secondary battery 100 in a high-temperature atmosphere. This is because, with the secondary battery 100, the voltage difference ΔV greatly increases as aging progresses. That is, by performing the determination cycle of step SA1 to step SA4 with respect to the voltage difference ΔV, the difference between a battery in which a minute internal short circuit has occurred and a battery that has not occurred (almost does not occur) becomes clear. It is thought that the accuracy could be improved.

  In the present embodiment, as shown in FIG. 6, both the first voltage measurement position C1 and the second voltage measurement position C2 are arranged in the aging device 500. That is, the first voltage measurement process (step S1) and the second voltage measurement process (step S3) are both provided in the aging process. In particular, the first voltage measurement position C <b> 1 is arranged at a position that reaches after the elapse of 1 to 3 days after the limiting jig 200 in which the secondary battery 100 is arranged is carried into the aging device 500. Although the temperature of the secondary battery 100 continues to rise for a while after being carried into the aging device 500, it is not stable. However, after 1 to 3 days have passed, the temperature reaches the temperature inside the aging device (about 40 ° C.). , Become stable.

  For this reason, in this embodiment, in the first voltage measurement step (step S1) and the second voltage measurement step (step S3), the temperature of the secondary battery 100 is stable at a high temperature (about 40 ° C.). The first terminal voltage V1 and the second terminal voltage V2 could be measured. Thereby, the reliability of the measured value of the voltage V1 between 1st terminals and the voltage V2 between 2nd terminals was able to be improved. Thus, the quality determination of the secondary battery 100 based on the highly reliable measurement values, the first inter-terminal voltage V1 and the second inter-terminal voltage V2 can also improve the accuracy of the quality determination. This is considered to be one of the factors.

Further, in the conventional method, the voltage between the terminals of the secondary battery was measured before and after the aging process, so after the aging process, the temperature of the secondary battery waited for the temperature to drop to the temperature before the aging process. Later, the voltage between terminals was measured. On the other hand, in the present embodiment, as described above, the temperature of the secondary battery 100 is stable at a high temperature (about 40 ° C.) at the first voltage measurement position C1 and the second voltage measurement position C2. Therefore, the voltage V1 between the first terminals and the voltage V2 between the second terminals could be measured promptly.
In addition, since both the first voltage measurement process (step S1) and the second voltage measurement process (step S3) can be completed during the aging process, the process time can be greatly reduced, and the secondary battery Productivity was improved.

  In the present embodiment, the 100 secondary batteries 100 arranged in the limiting jig 200 are set as one set of battery groups, and the initial charging process, the charging / discharging process, the aging process (the first voltage measuring process, the second voltage). Including a measurement process) and a determination process. In other words, the determination process (steps S2, S4 to SD) is performed on the group of the secondary batteries 100 that has been initially charged, charged / discharged, and aged under the same conditions. As described above, the group of the secondary batteries 100 that has been initially charged, charged / discharged, and aged under the same conditions has a small variation in the voltage V1 between the first terminals and the voltage V2 between the second terminals. The determination process (steps S2, S4 to SD) is also considered to be one of the factors that can improve the accuracy of the quality determination.

  By the way, in general, even in an aging process in which the temperature of the secondary battery becomes high, the internal pressure of the battery increases, so that the battery case may expand. In contrast, in the aging process of the present embodiment, as shown in FIG. 6, the secondary battery 100 is disposed and fixed on the limiting jig 200 (specifically, the expansion of the battery case 110 is expanded most). Aging is performed in a state where the first side wall 111c and the second side wall 111d tend to be in a tendency). Thereby, also in the aging process, the expansion of the battery case 111 can be appropriately suppressed, and distortion of the battery case 110, leakage of the electrolytic solution, and the like can be prevented.

In the above, the present invention has been described with reference to the embodiments. However, the present invention is not limited to the above embodiments, and it is needless to say that the present invention can be appropriately modified and applied without departing from the gist thereof.
For example, in the embodiment, in step SA, the determination cycle of steps SA1 to SA4 is performed for the voltage difference ΔV. However, the electrical characteristic value concerning the determination cycle of Step SA1 to Step SA4 is not limited to the voltage difference ΔV, and may be the second terminal voltage V2. Specifically, an average value V2ma of the second terminal voltage V2 is calculated in step SA1, and a standard deviation (σmV2) of the second terminal voltage V2 is calculated in step SA2. In step SA3, it may be determined whether or not | V2−V2ma | ≦ n (σmV2) is satisfied.

  Moreover, you may make it perform the determination cycle of step SA1-step SA4 about the voltage V1 between 1st terminals. Furthermore, two or more determination cycles selected from the determination cycle performed for the voltage difference ΔV, the determination cycle performed for the first inter-terminal voltage V1, and the determination cycle performed for the second inter-terminal voltage V2 may be combined.

  Moreover, although embodiment demonstrated the manufacturing method of the nickel hydride storage battery (secondary battery 100), the manufacturing method of this invention is not limited to a nickel hydride storage battery, but also about other secondary batteries (lithium ion battery etc.). Can be applied. Specifically, the quality of the secondary battery can be determined by performing the first voltage measurement process (step S1), the second voltage measurement process (step S3), and the determination process (steps S2, S4 to SD). Judgment can be made with high accuracy.

  Moreover, in the embodiment, the aging process (including the first voltage measurement process and the second voltage measurement process) was performed using the limiting jig 200 that can arrange the secondary batteries 100 in two rows of 50 pieces. However, the number of secondary batteries arranged in the limiting jig may be any number, and the form in which the secondary battery is arranged in the limiting jig may be any form. Moreover, you may make it perform an aging process, without arrange | positioning the secondary battery 100 to a restriction | limiting jig | tool.

1 is a front view of a secondary battery 100 according to an embodiment. 1 is a side view of a secondary battery 100 according to an embodiment. It is sectional drawing of the secondary battery 100 concerning embodiment, and is equivalent to AA sectional drawing of FIG. It is a figure which shows the limiting jig | tool 200 concerning embodiment, (a) is a top view, (b) is a side view. It is a figure which shows the state which has arrange | positioned and fixed the secondary battery 100 to the limiting jig | tool 200, (a) is a top view, (b) is a side view. It is explanatory drawing which shows the mode of the aging process (a 1st voltage measurement process and a 2nd voltage measurement process) concerning embodiment. It is a flowchart which shows the flow of the 1st voltage measurement process concerning embodiment, the 2nd voltage measurement process, and the determination process. It is a flowchart which shows the flow of the loop determination process concerning embodiment.

Explanation of symbols

100 Secondary battery 111e Third side wall (negative electrode)
140b First positive terminal 140c Second positive terminal 200 Limiting jig 500 Aging device C1 First voltage measurement position C2 Second voltage measurement position

Claims (7)

A first voltage measuring step for measuring, for each secondary battery belonging to the battery group, a first inter-terminal voltage V1 which is a voltage between terminals for each battery group including a predetermined number of secondary batteries as a set;
After the first voltage measurement step, for each battery group, for each secondary battery belonging to the battery group, a second voltage measurement step of measuring a voltage V2 between the second terminals, which is a voltage between the terminals,
For each of the battery groups, for each of the secondary batteries belonging to the battery group, determination for determining whether the electrical characteristics of the secondary battery are good or not based on the first inter-terminal voltage V1 and the second inter-terminal voltage V2. Process,
A method for producing a secondary battery comprising:
The first voltage measurement step and the second voltage measurement step are both provided in an aging step in which the secondary battery is placed in a high temperature atmosphere for a predetermined period, or
The first voltage measuring step is provided before the aging step, and the second voltage measuring step is provided after the aging step,
The determination process is as follows:
For each battery group, three electrical characteristic values are the first inter-terminal voltage V1, the second inter-terminal voltage V2, and the voltage difference ΔV between the first inter-terminal voltage V1 and the second inter-terminal voltage V2. For each of the electrical characteristic values selected from the above, the average value is calculated, the standard deviation of the selected electrical characteristic value is calculated, and among the secondary batteries belonging to the battery group, the electrical characteristic value and the average value are calculated. A secondary battery having an absolute value greater than the standard deviation value multiplied by a predetermined value n is determined to be defective,
For the other secondary batteries excluding the secondary battery determined to be defective among the secondary batteries belonging to the battery group, the average value of the electrical characteristic values is calculated again, and the standard deviation of the electrical characteristic values is calculated. Of the secondary batteries, a secondary battery in which the absolute value of the difference between the electrical characteristic value and the average value exceeds a value obtained by multiplying the standard deviation value by the predetermined value n is determined to be defective. A method for manufacturing a secondary battery including a loop determination step in which a determination cycle is repeated a plurality of times. A method of manufacturing a secondary battery according to claim 1,
The loop determination step is a method of manufacturing a secondary battery in which the determination cycle is performed for the voltage difference ΔV. A method of manufacturing a secondary battery according to claim 1 or claim 2,
A method for manufacturing a secondary battery, wherein both the first voltage measurement step and the second voltage measurement step are included in the aging step. It is a manufacturing method of the rechargeable battery according to claim 3,
The manufacturing method of the secondary battery which performs a said 1st voltage measurement process after the temperature of the said secondary battery is stabilized to predetermined | prescribed temperature among the said aging processes. It is a manufacturing method of the rechargeable battery according to any one of claims 1 to 4,
Before the aging step and the first voltage measurement step, a charge / discharge step of charging / discharging the secondary battery is provided,
The said battery group is the manufacturing method of the secondary battery which is the group of the predetermined number of secondary batteries which performed charging / discharging simultaneously by the same charging / discharging apparatus in the said charging / discharging process. A first voltage measuring step for measuring, for each secondary battery belonging to the battery group, a first inter-terminal voltage V1 which is a voltage between terminals for each battery group including a predetermined number of secondary batteries as a set;
After the first voltage measurement step, for each battery group, for each secondary battery belonging to the battery group, a second voltage measurement step of measuring a voltage V2 between the second terminals, which is a voltage between the terminals,
For each of the battery groups, for each of the secondary batteries belonging to the battery group, determination for determining whether the electrical characteristics of the secondary battery are good or not based on the first inter-terminal voltage V1 and the second inter-terminal voltage V2. Process,
A method for producing a secondary battery comprising:
A method of manufacturing a secondary battery, wherein the first voltage measurement step and the second voltage measurement step are both included in an aging step in which the secondary battery is placed in a high temperature atmosphere for a predetermined period. It is a manufacturing method of the rechargeable battery according to claim 6,
The manufacturing method of the secondary battery which performs a said 1st voltage measurement process after the temperature of the said secondary battery is stabilized to predetermined | prescribed temperature among the said aging processes.

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