JP2013137867A - Secondary battery device and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a secondary battery device in which a plurality of battery cells are appropriately allocated and which has leveled performance and less excess battery cells in manufacture, and a method of manufacturing the same.SOLUTION: A secondary battery device includes a first battery cell group having a first battery cell and a second battery cell connected in parallel, and a second battery cell group having a third battery cell and a fourth battery cell connected in parallel. The first battery cell group and the second battery cell group are connected in series. The first battery cell has a capacity value less than an average value of battery capacities of the first battery cell, the second battery cell, the third battery cell and the fourth battery cell. The second battery cell has a capacity value more than the average value. The third battery cell has a capacity value less than the average value. The fourth battery cell has a capacity value more than the average value.

Description

  Embodiments described herein relate generally to a secondary battery device and a manufacturing method thereof.

  Secondary batteries are used as power sources for a wide variety of applications. As a main application, it was used as a power source for small electric devices such as mobile phones, personal computers, and portable music players, but in recent years it is used for devices that require relatively large power, such as electric vehicles and power storage power sources. The development of large-sized battery devices has been promoted.

  There is a method of manufacturing a secondary battery device (battery pack) in which a plurality of batteries are connected in parallel in multiple series in order to deal with the above-described devices that require relatively large power, and using the secondary battery device as a large-scale power source.

JP2011-171032

  Each battery cell constituting a large-sized secondary battery device (battery pack) that repeatedly charges and discharges is often used connected in multiple parallel multiple series. For example, in a two-parallel multi-series secondary battery device, a battery cell having a similar capacity characteristic or self-discharge amount characteristic is selected as a method of maximizing the capacity of the battery cell in the battery apparatus. Has been preferred.

  However, when the method of collecting battery cells having similar characteristics is used, battery cells having similar characteristics are connected in parallel (hereinafter referred to as a battery cell group) as the first stage, and the battery cells are used as the second stage. The battery cell group having characteristics similar to the group had to be connected in series, and this was a battery cell selection method that was very easy to leave. This is because, when mass-producing a plurality of battery cells, the number distribution with respect to the capacity or self-discharge amount of the battery cells becomes a substantially normal distribution.

  The secondary battery device according to the present embodiment appropriately distributes a plurality of battery cells and leveles the performance, thereby maximizing the capabilities of each battery cell and selecting / selecting the battery cell at the time of manufacture. It is an object of the present invention to provide a secondary battery device or a method of manufacturing the secondary battery device that hardly causes a remainder due to the combination.

  The secondary battery device includes a first battery cell group having a first battery cell and a second battery cell connected in parallel, and a third battery cell and a fourth battery cell connected in parallel. And a second battery cell group. The first battery cell group and the second battery cell group are connected in series. The first battery cell has a capacity value smaller than an average value of battery capacities of the first battery cell, the second battery cell, the third battery cell, and the fourth battery cell, The second battery cell has a capacity value larger than the average value, the third battery cell has a capacity value smaller than the average value, and the fourth battery cell has a capacity value smaller than the average value. Large capacity value.

The perspective view which shows an example of the external appearance of the secondary battery apparatus 10 which concerns on 1st Embodiment. The perspective view which shows an example of the external appearance of the battery cell 12 which concerns on 1st Embodiment. The figure which looked at the secondary battery device 10 concerning a 1st embodiment from the upper surface. The figure which shows an example of the capacity | capacitance value of the battery cell 12 (alpha), (beta), (gamma), (delta) which concerns on 1st Embodiment. The figure showing an example of the number distribution of the capacity | capacitance or self-discharge amount of the battery cell 12 which concerns on 1st Embodiment. The perspective view which shows an example of the external appearance of the secondary battery apparatus 10 which concerns on 2nd Embodiment. The figure which looked at the rechargeable battery device 10 concerning a 2nd embodiment from the upper surface. The figure showing an example of the number distribution of the capacity | capacitance or self-discharge amount of the battery cell 12 which concerns on 1st Embodiment. The perspective view which shows an example of the external appearance of the secondary battery apparatus 10 which concerns on the modification 1. FIG. The figure which looked at the secondary battery apparatus 10 which concerns on the modification 1 from the upper surface. The perspective view which shows an example of the external appearance of the secondary battery apparatus 10 which concerns on the modification 2. FIG. The figure which looked at the secondary battery apparatus 10 which concerns on the modification 2 from the upper surface. The block diagram which shows an example of the arithmetic system which concerns on the modification 3. FIG. The figure which shows an example of the battery apparatus 2000 which concerns on the modification 3. The figure which shows an example of operation | movement of the arithmetic system which concerns on the modification 3.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is a perspective view illustrating an appearance of a secondary battery device 10 according to the present embodiment. A secondary battery device may be referred to as a battery module, and a device including a plurality of secondary battery devices (battery modules) may be referred to as a battery pack.

  As shown in FIG. 1, the secondary battery device 10 has, for example, a configuration having a plurality of secondary battery cells 12α,. These four battery cells 12 are arranged in series by two battery cells and electrically connected by a bus bar 14 to form two battery cell rows. The two battery cell rows are arranged in parallel and electrically connected using the bus bar 14 to constitute the secondary battery device 10.

  FIG. 2 is a perspective view showing the appearance of the secondary battery cell 12.

  Each battery cell 12 (12α,... 12δ) is a non-aqueous electrolyte secondary battery such as a lithium ion battery, for example, a flat, substantially rectangular parallelepiped outer container 21 formed of aluminum or an aluminum alloy, and an outer container The electrode body accommodated together with the non-aqueous electrolyte, the positive electrode terminal 22a, and the negative electrode terminal 22b are provided. Instead of the aluminum can, the outer container 21 may be a can made of another metal such as iron, a laminate film (pouch, polymer), or a resin material.

  The outer container 21 has a container main body with an open upper end and a rectangular plate-shaped lid body that is welded to the container main body and closes the opening of the container main body, and is formed fluid-tight. The electrode body is formed in a flat rectangular shape, for example, by winding a positive electrode plate and a negative electrode plate in a spiral shape with a separator interposed therebetween, and further compressing in a radial direction.

  The positive electrode (positive electrode terminal) 22 a and the negative electrode (negative electrode terminal) 22 b are provided at both ends in the longitudinal direction of the lid body 23, and project from the lid body 23. The positive electrode terminal 22a and the negative electrode terminal 22b are connected to the positive electrode and the negative electrode of the electrode body, respectively. One terminal, for example, the positive electrode terminal 22 a is electrically connected to the lid body 23 and has the same potential as the outer container 21. The negative terminal 22 b extends through the lid body 23. Between the negative electrode terminal 22b and the lid 23, a sealing material made of an insulating material such as synthetic resin or glass, for example, a gasket is provided.

  An insulating film is wound around the container body except for the upper end and the lower end of the container. This film regulates expansion of the outer container and prevents a short circuit between the outer container and the other battery cell 12 or a short circuit between the outer container and the other member.

  As shown in FIG. 1, the bus bar 14 (14α,..., 14δ) is a conductive member that electrically connects the plurality of battery cells 12 in series or in parallel. The plurality of battery cells 12 are arranged in the direction in which the positive electrode terminals and the negative electrode terminals of adjacent battery cells 12 are aligned. Each bus bar 14 is formed of a metal plate made of a conductive material, for example, aluminum. One end of the bus bar 14 is joined to the positive terminal 22a of the battery cell 12, and the other end is welded to the negative terminal 22b of the adjacent battery cell 12 to electrically connect these electrode terminals. Thus, the nine battery cells 12 are connected in series by the plurality of bus bars 14. Similarly, the plurality of battery cells 12 are also used when the positive electrodes and the negative electrodes are connected in parallel.

  FIG. 3 is a view of the secondary battery device 10 according to the first embodiment as viewed from above.

  FIG. 4 is a diagram illustrating an example of capacity values of the battery cells 12α, β, γ, and δ according to the first embodiment.

  In this embodiment, the battery cell 12α is 18.0 [Ah], the battery cell 12β is 22.0 [Ah], the battery cell 12γ is 19.5 [Ah], and the battery cell 12δ is 20.5 [Ah]. It has.

The intermediate value of the battery capacity of these four battery cells is
(18.0 + 22.0 + 19.5 + 20.5) /4=20.0 [Ah]
It is.

  Among these, since the battery cell 12α is lower than the intermediate value, the battery cell 12β or 12δ is selected as a parallel connection candidate.

(Example 1) For example, when the battery cell 12α and the battery cell 12β are connected in parallel,
A battery cell group 1 connected in parallel with an average value of battery capacity of 20.0 [Ah] and a total of 40.0 [Ah] is formed.

The other battery cell group 2 is composed of the remaining battery cells 12γ and 12δ. Similarly, a battery cell group 2 connected in parallel with an average battery capacity value of 20.0 [Ah] and a total of 40.0 [Ah] It is formed.

  The battery cell group 1 and the battery cell group 2 can be connected to battery cells whose average and total battery capacities are similar as the battery cell group.

(Example 2) When battery cell 12α and battery cell 12δ are connected in parallel,
A battery cell group 1 connected in parallel with an average value of battery capacity of 19.25 [Ah] and a total of 38.5 [Ah] is formed.

In addition, the battery cell 12β and the battery cell 12γ are connected in parallel,
The battery cell group 2 connected in parallel with an average value of 20.75 [Ah] for battery capacity and a total of 41.5 [Ah] is formed.

  In this case, the difference between the average values of the battery capacities of the battery cell groups is 1.5 [Ah], and the difference between the total values is 3.0 [Ah].

  On the other hand, the case where the battery cell groups 1 and 2 are comprised with similar battery cells is described.

(Example 3) For example, when battery cell 12α and battery cell 12γ are connected in parallel,
A battery cell group 1 connected in parallel with an average value of battery capacity of 18.75 [Ah] and a total of 37.5 [Ah] is formed.

On the other hand, the battery cell 12β and the battery cell 12γ are connected in parallel,
The battery cell group 2 connected in parallel with an average value of battery capacity of 21.25 [Ah] and a total of 42.5 [Ah] is formed.

  When these two battery cell groups are connected in series, the difference between the average values of the battery capacities is 2.5 [Ah], and the difference between the total values is 5.0 [Ah].

  When the secondary battery device is configured by battery cells or battery cell groups connected in series, the capacity characteristic of the secondary battery device described above is the capacity of the battery cell or battery cell group having the lowest battery capacity. Therefore, the capacity characteristics of the secondary battery device of Example 3 are also lower than those of Examples 1 and 2. On the other hand, the working voltage range of the secondary battery device can be forcibly expanded, and the secondary battery device of Example 3 can be operated with the same battery capacity as in Examples 1 and 2. In that case, a battery cell or a battery cell group in an overdischarged state or an overcharged state is generated, and the life of the secondary battery device is remarkably shortened. Therefore, when connected in series, it is evaluated as a secondary battery device that matches the battery cell group with the lowest battery capacity, and the performance of the secondary battery device of Example 3 compared to Examples 1 and 2 above is from the viewpoint of battery capacity. It will be low to see.

(Example 4) In addition, when the selection method of the battery cell of the similar characteristic is taken similarly,
The battery cell group 1 is formed by a combination of the battery cell 12γ and the battery cell 12δ. The other battery cell 12α and the battery cell 12β are not selected because they do not have similar characteristics, and a secondary battery device that is not used or hardly exhibits performance, such as being discarded as a surplus battery cell, must be configured.

  That is, as shown in FIG. 5, the battery cell 12 is divided into a region 1 (small capacity side) and a region 2 (large capacity side), and battery cells selected from different regions are connected in parallel. A battery cell group is formed. By connecting the battery cell groups in series, the secondary battery device of the present embodiment is formed.

  In general, when the environmental temperature is high in a secondary battery, a chemical reaction not related to charging / discharging increases, and deterioration is accelerated. Therefore, when the temperature rise due to internal heat generation of the secondary battery device is not uniform, even if the total amount of self-heating of the battery cell or battery cell group is the same in the secondary battery device, the battery is exposed to a high environmental temperature. A cell or battery cell group is generated, and the battery cell or battery cell group deteriorates intensively. As described above, in the case of a secondary battery device in which battery cells or battery cell groups are connected in series, the capacity characteristic of the secondary battery device is a secondary battery device that matches the battery cell or battery cell group having the lowest battery capacity. Be evaluated. Therefore, when the temperature rise due to internal heat generation of the secondary battery device is not uniform, the lifetime as the secondary battery device is shortened compared to the case where the temperature rise is uniform.

  On the other hand, the battery self-heats during charge / discharge due to its internal resistance. Self-heating is larger when the ratio of current / capacitance flowing through the battery cells is larger, and smaller when the ratio is smaller. In a secondary battery device composed of a plurality of battery cells or battery cell groups connected in series, the value of the flowing current is constant. Therefore, the self-heating amount of the battery cell or the battery cell group having a smaller capacity becomes larger. Further, since the internal resistance increases at the end of discharge, the amount of self-heat generation increases. In a secondary battery device composed of a plurality of battery cells or battery cell groups connected in series, a plurality of battery cells or battery cell groups are closely stored in the secondary battery device. The temperature environment is largely due to the self-heating of the battery cell or battery cell group. Therefore, in order to improve the uniformity of temperature rise in the secondary battery device, by arranging the large capacity and low capacity battery cells or the large self discharge amount and low self discharge amount alternately, The heat distribution of the self-heating amount of the battery cell due to the difference in the charged state (or discharged state) after storage can be made uniform, and the life of the secondary battery device can be extended. For example, in the battery cell group 1, when the amount of self-discharge of the battery cell 12β is large and heat is likely to be generated at the end of discharge, in the other battery cell group 2, the battery cell 12δ having a small self-discharge amount is directly connected to the bus bar 14. It is easy to disperse heat by installing it at a position where it is not connected.

  As described above, in the secondary battery device composed of a plurality of battery cell groups, the battery cells in parallel relation are the average of the battery capacities (or self-discharge amounts) of all the battery cells constituting the secondary battery cell. A combination of battery cells having higher and lower battery capacities is selected. By connecting these battery cell groups in series, a secondary battery device with a certain performance or more is obtained. In addition, the secondary battery device is less likely to have a surplus in mass production of a plurality of secondary battery devices.

  Next, the self-discharge amount is illustrated. As an example, battery cell 12ε (15.0 [mAh / day]), battery cell 12γ (25.0 [mAh / day]), battery cell 12φ (18.0 [mAh / day]), and battery cell 12η (22 .0 [mAh / day]) is manufactured.

(Example 5) For example, when the battery cell 12ε and the battery cell 12γ are connected in parallel,
A battery cell group 3 connected in parallel with an average value of self-discharge amount of 20.0 [mAh / day] and a total of 40.0 [mAh / day] is formed.

The other battery cell group 4 is composed of the remaining battery cells 12φ and 12η, and similarly connected in parallel with an average self-discharge amount of 20.0 [mAh / day], totaling 40.0 [mAh / day]. It is formed as a battery cell group.

  The battery cell group 3 and the battery cell group 4 can be connected to those whose average value and total value of the self-discharge amount are similar as the battery cell group.

(Example 6) When battery cell 12ε and battery cell 12η are connected in parallel,
Battery cell group 3 connected in parallel with an average self-discharge amount of 18.5 [mAh / day] and a total of 37.0 [mAh / day] is formed.

In addition, the battery cell 12γ and the battery cell 12φ are connected in parallel,
A battery cell group 4 connected in parallel with an average value of self-discharge amount of 21.5 [mAh / day] and a total of 43.0 [mAh / day] is formed.

  In this case, the difference between the average values of the self-discharge amounts of the battery cell groups is 3.0 [mAh / day], and the difference between the total values is 6.0 [mAh / day].

  On the other hand, the case where the battery cell groups 3 and 4 are constituted by battery cells having similar self-discharge amounts will be described.

(Example 7) For example, when battery cell 12ε and battery cell 12φ are connected in parallel,
The battery cell group 3 connected in parallel with an average value of self-discharge amount of 16.5 [mAh / day] and a total of 33.0 [mAh / day] is formed.

On the other hand, the battery cell 12γ and the battery cell 12η are connected in parallel,
A battery cell group 4 connected in parallel with an average self-discharge amount of 23.5 [mAh / day] and a total of 47.0 [mAh / day] is formed.

  When these two battery cell groups are connected in series, the difference in the average value of the self-discharge amount is 7.0 [mAh / day], and the difference in the total value is 14.0 [mAh / day].

  When a secondary battery device is configured with battery cells or battery cell groups connected in series, if the secondary battery device is stored for a long period of time without being charged and discharged arbitrarily, the battery cell or battery cell group can be charged individually. The state (or discharge state) is different here, and the balance of the secondary battery device as a whole is lost.

  When a secondary battery device is discharged after being stored for a long period of time and significantly out of balance, the battery cell that has a large self-discharge amount and is more discharged than other battery cells or battery cell groups first reaches the lower limit voltage However, when charged, the amount of self-discharge is small, and the battery cells that are not discharged more than the other battery cells or battery cell groups first reach the upper limit voltage for use, and the capacity of the secondary battery device is less than before storage It will be. Therefore, in the secondary battery device of Example 7 as compared with Examples 5 and 6, the storage period must be set shorter from the viewpoint of maintaining the capacity, or the capacity is reduced by short-term storage.

  Note that the secondary battery device of Example 7 can be operated in the same environment as in Examples 5 and 6 by forcibly extending the storage period and the operating voltage range of the secondary battery device. In this case, overcharged or overcharged battery cells or battery cell groups are generated, and the life of the secondary battery device is remarkably shortened.

(Second Embodiment)
FIG. 6 is a perspective view showing an appearance of the secondary battery device 10 according to the present embodiment.

  As shown in FIG. 6, the secondary battery device 10 has, for example, a configuration having a plurality of secondary battery cells 12 a,. These nine battery cells 12 are arranged in series by three battery cells and electrically connected by the bus bar 14 to form three battery cell rows. These three battery cell rows are arranged in parallel and electrically connected using the bus bar 14 to constitute the secondary battery device 10.

  The description of the same components (battery cells 12, bus bars 14, etc.) as in the first embodiment is omitted.

  FIG. 8 is a diagram illustrating an example of the dispersion of the capacity values of the battery cells 12a,..., 12i according to the first embodiment. The small capacity region is 18.5 to 19.5 [Ah], the medium capacity region is 19.5 to 20.5 [Ah], and the large capacity region is 20.5 to 21.5 [Ah].

  In the present embodiment, the battery cells 12a, 12b, and 12c belong to the region 1 (small capacity region), the battery cells 12d, 12e, and 12f belong to the region 2 (medium capacity region), and the battery cells 12g, 12h, and 12i belong to the region. 3 (large capacity area). In the present embodiment, the number of these three regions is determined by dividing the number of battery cells into three equal parts depending on whether the battery capacity is large or small. For example, in the present embodiment, since nine battery cells exist, three battery cells exist in each region. The battery cells belonging to these small capacity areas are less than the battery capacity of the battery cells belonging to the medium capacity area and the large capacity area. A battery cell belonging to the medium capacity region has a larger battery capacity than a battery cell belonging to the small capacity region, and has a smaller battery capacity than a battery cell belonging to the large capacity region. The battery cell belonging to the large capacity region has a larger battery capacity than the battery cell belonging to the small capacity region and the medium capacity region.

  Further, when the fraction is obtained, it is preferable to divide into three equal parts by excluding the battery with the smallest capacity or the battery with the largest capacity.

  In addition, the upper and lower critical points between the regions may be set so that the number of battery cells is exactly divided into three, and the regions may be divided.

  For example, when there are 21 battery cells, if there are 8 in the set small capacity area, 6 in the medium capacity area, and 7 in the large capacity area, the lower limit of the medium capacity area is set to the small capacity area. It is preferable to reset to 7 in the small capacity area, 7 in the medium capacity area, and 7 in the large capacity area. It can be used for correction from the normal distribution due to each manufacturing process difference.

  A battery cell group in which three battery cells are connected in parallel is formed using one battery cell belonging to each of the regions 1, 2, and 3. The battery cells are connected in series to form a secondary battery device.

  By combining the secondary battery devices in this way, it is possible to realize a secondary battery device in which battery cells having similar characteristics compared to the case of connecting two battery cells in parallel are connected in parallel in the order of capacity.

(Modification 1)
This embodiment is a modification of the first embodiment.

  The classification of the component and the capacity is large and small, as in the first embodiment.

  Thus, the battery cells 12α and 12γ are regarded as one battery cell, and the battery cells 12β and 12δ are regarded as one battery cell.

  By doing in this way, it is hard to produce a more unnecessary battery cell. It is also effective when the capacity difference between the plurality of battery cells is very small.

(Modification 2)
This embodiment is a modification of the second embodiment.

  The components and the capacity are large and small are the same as in the first embodiment.

  Thus, the battery cells 12a, 12b, and 12c are regarded as one battery cell, the battery cells 12d, 12e, and 2f are regarded as one battery cell, and the battery cells 12g, 12h, and 12i are regarded as one battery cell.

  By doing in this way, the secondary battery apparatus which is hard to produce a more unnecessary battery cell is made.

(Modification 3)
The present embodiment is an example of a manufacturing method for manufacturing the secondary battery device of the first embodiment and the second embodiment.

  For example, when there are a plurality of secondary battery devices used as in-vehicle batteries, they are disassembled and disassembled in units of battery cells. In this case, a secondary battery device using the same number of cycles is preferable. The battery capacity or self-discharge amount of the plurality of battery cells is measured and classified. At this time, it is desirable to create a distribution table or a distribution table as shown in FIGS. 5 and 8 by an arithmetic unit including a CPU and a ROM shown in FIG.

  The arithmetic device 1000 of this modification includes a CPU 100, a RAM (RWM) 110, a communication IF 120, an input IF 130, a display IF 140, a ROM 150, a storage unit 160, and a timer 170. In addition, an IF (interface) for mounting an external storage device such as a USB memory may be provided. The arithmetic device 1000 is a computer that executes and calculates a program.

  Arithmetic device 1000 collects data such as current value and environmental temperature from secondary battery device 2000 through communication IF 120, and uses the collected data to determine the capacity, CMU (cell monitoring unit) or two of each battery cell. Arithmetic processing such as assigning a number to a BMU (Battery management unit) of a secondary battery device (which may be referred to as a battery module) is performed.

  The CPU 100 is an arithmetic processing unit (microprocessor) that reads each program written in advance in the ROM 150 into the RAM 110 and performs arithmetic processing. The CPU 100 can be composed of a plurality of CPU groups in accordance with functions. Further, a built-in memory having a RAM function may be provided in the CPU.

  A RAM (RWM) 110 is a storage area used when the CPU 100 executes a program, and is a memory used as a working area. It is suitable for temporarily storing data necessary for processing.

  The communication IF 120 is a communication device and a communication unit that exchange data with the secondary battery device. For example, there is a router. In the present embodiment, the connection between the communication IF 20 and the secondary battery device 2000 is described as in wired communication, but can be replaced with various wireless communication networks. In addition, the connection between the communication IF 20 and the secondary battery device 2000 may be performed via a network that is capable of one-way or two-way communication.

  The input IF 130 is an interface that connects the input unit 130 and the arithmetic device 1000. You may have the input control function which converts the input signal sent from the input part 131, and converts it into the signal which CPU100 can recognize. This IF is not an essential component as a terminal or the like, and may be directly connected to wiring in the arithmetic device.

  The input unit 131 is an input device or an input unit that performs input control of various keyboards and buttons that are generally provided in a computer device. In addition, a function of recognizing or detecting an input signal by recognizing a voice uttered by a person may be provided. In this embodiment, it is installed outside the arithmetic device 1000, but may be incorporated in the arithmetic device.

  The display IF 140 is an interface that connects the display unit 140 and the arithmetic device 1000. Display control of the display unit 130 may be performed from the CPU 100 via the display IF 141, or display control may be performed by an LSI (GPU) that performs drawing processing such as a graphic board. As a display control function, for example, there is a decoding function for decoding image data. It may be configured to be directly connected to the inside of the arithmetic device 1000 without using the IF.

  The display unit 141 is an output device or output unit such as a liquid crystal display, an organic EL display, or a plasma display. In addition, you may provide the function to emit a sound. In this embodiment, it is installed outside the arithmetic device 1000, but may be incorporated in the arithmetic device 1000.

  The ROM 150 is a program memory that stores a capacity calculation program 151, a numbering program 152, a distribution calculation program 153, an area calculation program 154, and a redistribution program 155. A non-primary storage medium that cannot write data is preferably used, but a storage medium such as a semiconductor memory that can read and write data at any time may be used. In addition, a display program for displaying image data on characters and designs that can be recognized by a person on the display unit 141, a program for transmitting content to an external device via the communication IF 120, and acquired data are predetermined in the storage unit 160. In addition, a registration program to be stored every time may be stored.

  The capacity calculation program 151 is a means for causing the CPU 100 to realize a function of acquiring the capacity value [Ah] of the battery cell 12 or calculating from the current value, voltage value, and the like. The acquired or generated capacity value is stored in the capacity value DB 161.

  The numbering program 152 is a means for causing the CPU 100 to realize a function of giving an identification number (ID) to each battery cell 12. These numbers are transmitted to the BMU of each secondary battery device (battery module) and the CMU of each battery cell via the communication unit 120 to give the numbers. The given number is stored in the numbering DB 162. For example, when there are 12 battery cells, numbers 1 to 12 are assigned in order.

  The distribution calculation program 153 is a means for causing the CPU 100 to realize the function of calculating the number distribution for each capacity [Ah] using the capacity value [Ah] obtained in the capacity calculation program 151. The calculation processing result is stored in the distribution DB 163 in a table format or a data format. For example, a distribution map as shown in FIGS. 5 and 8 is created.

  The area calculation program 154 is means for causing the CPU 100 to realize a function of calculating an area from the number distribution. The calculated area is stored in the area DB 164. For example, the number of regions is divided according to the number of battery cells 12 input in the input unit 131 and desired to be arranged in parallel. The CPU 100 may further have a function of realizing a function of adjusting the critical point of each region so as to match the number of battery cells 12.

  The redistribution program 155 is a means for causing the CPU 100 to realize a function of distributing the positions of the battery cells 12 in the secondary battery device in accordance with the area where the battery cells 12 are distributed. The calculated result is stored in the redistribution DB 165. For example, in the case of three parallel secondary battery devices, the CPU 100 is caused to realize a function of rearranging the battery cells according to the battery cells, distribution, and regions stored in the numbering DB 162, the distribution DB 163, and the region DB 164.

  The storage unit 160 stores a capacity value DB 161, a numbering DB 162, a distribution DB 163, an area DB 164, and a redistribution DB 165. In addition, data necessary for the arithmetic processing of the CPU 100 is stored.

  The capacity value DB 161 stores the acquired or calculated capacity value of the battery cell 12 stored in the target secondary battery device 2000.

  The numbering DB 162 stores the identification number (ID) of the target battery cell.

The distribution DB 163 stores the capacity values of the target battery cells and information indicating the distribution of the self-discharge amount. The area DB 164 is the number of areas divided by the parallel number of secondary battery devices to be manufactured after redistribution and the criticality. Stores a value.

  The redistribution DB 165 stores battery cell arrangement information suitable for the secondary battery device after redistribution.

  The timer 170 is a clock for measuring time. Using the measured time, the CPU 100 measures and stores current values and voltage values. Arithmetic device 1000 may be configured to acquire time via a network instead of timer 170, or may be configured to calculate time from measurement by timer 170 and time obtained from the network.

  The secondary battery device 2000 is a device including a battery and a control circuit (BMU, CMU, etc.) that measures the current value, voltage value, and the like of the battery. Various secondary batteries can be used as the battery.

  Next, the manufacture of the secondary battery device according to Modification 3 will be described with reference to FIG.

  FIG. 15 is a flowchart showing a method for manufacturing a double secondary battery device using the arithmetic system of the third modification.

  First, a target secondary battery device is selected.

  First, the capacity value of the battery cell in the selected secondary battery device is acquired and calculated (S102).

Next, each battery cell 12 is given a number, and distribution information is created according to the capacity and the number of battery cells (S103).
The arrangement position of the battery cells is determined according to the number of battery cells to be arranged in parallel. A secondary battery device is created according to the rearranged information (S104).

  Thus, according to this modification, appropriate battery cell distribution can be realized when reusing a secondary battery once used.

  The lithium-ion secondary battery that constitutes the secondary battery device described in each of the above embodiments and modifications, for example, is a non-aqueous secondary battery, such as an electric vehicle, a hybrid electric vehicle, a power source of an electric bicycle, or an electric It can be used as a power source for equipment.

  In addition, when applied to these, the secondary battery has a plurality of battery cells arranged in a case in order to increase the capacity and output, and these battery cells are connected in parallel or in series. The secondary battery device can be used as a battery pack in which a plurality of secondary battery devices are connected.

  As mentioned above, although embodiment of this invention was described, this embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. For example, in the present embodiment, the upper surface cover and the connecting member are described as metal members, but a battery cell using a so-called laminate as an exterior material may be used, or a plurality of coils may be provided inside one exterior material. The battery cell provided may be sufficient. In each of the embodiments, four battery cells are described in the first embodiment and nine battery cells are used in the second embodiment. However, the number of battery cells is not limited to this number. 4, 6..., A multiple of 3 (3, 6, 9...), And a multiple of n (n is a positive integer) (n, 2n, 3n... Nn).

  Instead of a nonaqueous electrolyte secondary battery such as a lithium ion battery, a secondary battery such as a nickel metal hydride battery, a nickel cadmium battery, a lead storage battery, an aluminum battery, a magnesium battery, a solid electrolyte battery, or an air battery may be used. Compared to lead-acid batteries, nickel-cadmium batteries, and lead-acid batteries, lithium-ion batteries, aluminum batteries, etc. have higher output characteristics per unit capacity, causing large currents to flow through the battery cells, thus increasing self-heating. is there. Therefore, the present embodiment is more suitable for a high output secondary battery such as a lithium ion battery.

  These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

10 ... Secondary battery device 12 (12a, ... 12s) ... Battery cell (cell)
14 (14a, ..., 14t) ... bus bar 21 ... outer can 22a ... positive electrode (positive electrode terminal)
22b ... Negative electrode (negative electrode terminal)
23 ... Lid (lid)

Claims (10)

A first battery cell group having a first battery cell and a second battery cell connected in parallel;
A second battery cell group having a third battery cell and a fourth battery cell connected in parallel;
With
A secondary battery device for connecting the first battery cell group and the second battery cell group in series,
The first battery cell has a capacity value smaller than an average value of battery capacity of the first battery cell, the second battery cell, the third battery cell, and the fourth battery cell,
The second battery cell has a capacity value larger than the average value,
The third battery cell has a capacity value smaller than the average value,
The fourth battery cell is a secondary battery device having a capacity value larger than the average value. A first battery cell group having a first battery cell, a second battery cell, and a third battery cell connected in parallel;
A second battery cell group having a fourth battery cell, a fifth battery cell, and a sixth battery cell connected in parallel;
With
A secondary battery device for connecting the first battery cell group and the second battery cell group in series,
According to the battery capacity values of the first battery cell, the second battery cell, the third battery cell, the fourth battery cell, the fifth battery cell, and the sixth battery cell. When divided into three areas of small capacity area, medium capacity area and large capacity area,
The first battery cell and the fourth battery cell belong to a small capacity region,
The second battery cell and the fifth battery cell belong to a medium capacity region,
The third battery cell and the sixth battery cell are secondary battery devices belonging to a large capacity region. A first battery cell group having a first battery cell and a second battery cell connected in parallel;
A second battery cell group having a third battery cell and a fourth battery cell connected in parallel;
With
A secondary battery device for connecting the first battery cell group and the second battery cell group in series,
The first battery cell has a self-discharge amount smaller than an average value of battery capacities of the first battery cell, the second battery cell, the third battery cell, and the fourth battery cell,
The second battery cell has a self-discharge amount larger than the average value,
The third battery cell has a self-discharge amount smaller than the average value,
The fourth battery cell is a secondary battery device having a self-discharge amount larger than the average value. A first battery cell row having a first battery cell and a second battery cell connected in series;
A second battery cell row having a third battery cell and a fourth battery cell connected in series;
With
Connecting the first battery cell row and the second battery cell row in parallel;
The first battery cell constituting the first battery cell row is based on an average value of battery capacities of the first battery cell, the second battery cell, the third battery cell, and the fourth battery cell. Is less capacity value,
The second battery cell has a capacity value smaller than the average value,
The third battery cell has a capacity value larger than the average value,
The fourth battery cell is a secondary battery device having a capacity value larger than the average value. The average value of the battery capacity of the first battery cell and the second battery cell is
The capacity value is smaller than the average value,
The average value of the battery capacity of the third battery cell and the fourth battery cell is
The secondary battery device according to claim 4, wherein the capacity value is larger than the average value. A first battery cell group having a first battery cell and a second battery cell;
A second battery cell group having a third battery cell and a fourth battery cell;
With
A method of manufacturing a secondary battery device for connecting the first battery cell group and the second battery cell group,
The first battery cell having a capacity value smaller than an average value of battery capacities of the first battery cell, the second battery cell, the third battery cell, and the fourth battery cell, and the average value Connecting the second battery cell having a larger capacity value in parallel,
Connecting the third battery cell having a capacity value smaller than the average value and the fourth battery cell having a capacity value larger than the average value in parallel;
A method for manufacturing a secondary battery device, wherein the first battery cell group and the second cell group are connected in series. The first battery cell having a small capacity value, the third battery cell, the second battery cell having a large capacity, and the fourth battery cell are installed so as to be alternately adjacent to each other. To manufacture a secondary battery. A first battery cell group having a first battery cell, a second battery cell, and a third battery cell;
A second battery cell group having a fourth battery cell, a fifth battery cell, and a sixth battery cell;
With
A method of manufacturing a secondary battery device for connecting the first battery cell group and the second battery cell group,
2 depending on the value of the battery capacity of the first battery cell, the second battery cell, the third battery cell, the fourth battery cell, the fifth battery cell, and the sixth battery cell. When divided into three areas,
Connecting the first battery cell belonging to the small capacity region, the second battery cell belonging to the medium capacity region, and the third battery cell belonging to the large capacity region in parallel;
Connecting the fourth battery cell belonging to the small capacity region, the fifth battery cell belonging to the medium capacity region, and the sixth battery cell belonging to the large capacity region in parallel;
The manufacturing method of the secondary battery apparatus which connects the said 1st battery cell group and the said 2nd battery cell group in series. Installing the first battery cell and the sixth battery cell adjacent to each other;
The method for manufacturing a secondary battery according to claim 8, wherein the third battery cell and the fourth battery cell are installed adjacent to each other. In an arithmetic device equipped with an arithmetic processing unit,
A first calculation process for calculating the battery capacity of a plurality of battery cells constituting the secondary battery device;
A second calculation process for giving an identification number to the plurality of secondary battery cells;
A third calculation process for calculating a number distribution for the capacity of the plurality of secondary battery cells;
A fourth calculation process for setting an area in the number distribution;
A fifth calculation process for determining an arrangement position of the plurality of battery cells in the secondary battery device according to the region;
How to realize.

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