阅读说明：本技术 包括并联电池单元的电池单元切换装置的电池组和电池单元切换方法 (Battery pack including cell switching device for parallel-connected cells and cell switching method ) 是由 金正完 于 2020-11-30 设计创作，主要内容包括：本发明涉及一种包括并联电池单元的电池单元切换装置的电池组和电池单元切换方法,具体而言,涉及一种包括电池单元切换装置的电池组和电池单元切换方法,如果在并联电池单元中由于并联连接线开路或CID操作而出现故障电池单元,则该电池单元切换装置将故障电池单元替换为正常的替换用电池单元。(The present invention relates to a battery pack including a cell switching device of parallel-connected cells and a cell switching method, and more particularly, to a battery pack including a cell switching device which replaces a failed cell with a normal replacement cell if the failed cell occurs in parallel-connected cells due to open of parallel-connected lines or CID operation.)

1. A battery pack including at least one parallel row of battery cells formed by arranging a plurality of battery cells in parallel, the battery pack comprising:

a first cell group configured by connecting a predetermined number of sequentially adjacent battery cells in parallel from a first battery cell among the battery cells constituting the parallel rows of battery cells; and

a second cell group configured by connecting in parallel the remaining battery cells, excluding the battery cells arranged as the first cell group, among the battery cells constituting the parallel rows of the battery cells,

wherein the first cell stack and the second cell stack are electrically separated,

wherein, among the battery cells of the second cell line, the battery cell closest to the first cell line is set as a replacement battery cell,

wherein, when a faulty battery cell occurs in the first battery cell group, the replacement battery cell is electrically separated from the second battery cell group and is connected in parallel to the first battery cell group to replace the faulty battery cell.

2. The battery pack according to claim 1, further comprising a switch configured to perform a switching operation to replace a failed battery cell occurring in the first cell group with the replacement battery cell,

wherein the switch comprises:

a first switch provided on a first parallel connection line connecting the replacement battery cell of the second battery cell group and the battery cell of the first battery cell group in parallel to control a connection current between the replacement battery cell and the first battery cell group; and

and a second switch provided on a second parallel connection line connecting the replacement battery cell and the remaining battery cells of the second battery cell group in parallel to control a connection flow between the replacement battery cell and the remaining battery cells.

3. The battery pack according to claim 2, further comprising a control unit configured to control switching operations of the first and second switches according to whether a faulty battery cell occurs in the first cell group due to an open parallel connection line or a CID operation.

4. The battery pack according to claim 3, wherein, in the case where a normal state of a failed battery cell does not occur in the first cell group, the control unit turns off the first switch and turns on the second switch, thereby cutting off the connection of the replacement battery cell with the battery cell of the first cell group and connecting the replacement battery cell to the remaining battery cells of the second cell group.

5. The battery pack according to claim 4, wherein, when a faulty battery cell occurs in the first cell group, the control unit turns on the first switch and turns off the second switch to separate the replacement battery cell from the second cell group and connect the replacement battery cell to the battery cell of the first cell group, thereby replacing the faulty battery cell with the replacement battery cell.

6. The battery pack according to any one of claims 1 to 5, wherein the first cell group operates as a main power source of a device in which the battery pack is mounted, and the second cell group operates as an auxiliary power source of the device.

7. A battery cell switching method, comprising:

a battery cell parallel row forming step of arranging a plurality of battery cells in parallel to form a battery cell parallel row;

a cell group setting step of connecting a predetermined number of battery cells in parallel in order from a first battery cell among the battery cells constituting the parallel rows of battery cells to set up as a first cell group, and connecting the remaining battery cells except the battery cells set up as the first cell group in parallel to set up as a second cell group;

a defective cell detecting step of detecting whether a defective cell occurs in the first cell group due to an open circuit of a parallel connection line or a CID operation; and

and a defective battery cell replacement step of replacing, when a defective battery cell occurs in the first battery cell group, the defective battery cell with a replacement battery cell belonging to the second battery cell group.

8. The method of claim 7, wherein the faulty cell replacement step comprises:

a replacement battery cell separation step of electrically separating the replacement battery cell from the second battery cell group by turning off a second switch provided on a parallel connection line between the replacement battery cell and the remaining battery cells of the second battery cell group; and

a replacement battery cell connection step of connecting in parallel the replacement battery cells separated from the second battery cell group to the first battery cell group by turning on a first switch provided on a parallel connection line between the replacement battery cells and the battery cells of the first battery cell group.

9. The method according to claim 8, wherein the replacement battery cell is closest to the first cell stack among the battery cells of the second cell stack.

10. The method according to any one of claims 7 to 9, wherein the first cell group operates as a main power source of a device in which a battery pack is installed, and the second cell group operates as an auxiliary power source of the device.

Technical Field

The present invention relates to a battery pack including a cell switching device that connects battery cells in parallel and a cell switching method, and more particularly, to a battery pack including a cell switching device that replaces a specific disconnected battery cell among the battery cells connected in parallel with a replacement battery cell and a cell switching method.

Background

Unlike primary batteries that cannot be recharged, rechargeable secondary batteries are widely used in various fields of electric bicycles, electric vehicles, and Energy Storage Systems (ESS) as well as small high-technology electronic devices such as smart phones, notebook computers, and tablet PCs.

Since middle-and large-sized devices, such as electric bicycles, electric vehicles, and Energy Storage Systems (ESS), require high power and large capacity, when the secondary battery is applied to the middle-and large-sized devices, a plurality of battery cells are connected in series/parallel to use a battery pack electrically connected to each other.

Generally, a battery cell included in a battery pack is equipped with a Current Interrupt Device (CID), which is a protective element that ensures safety during charging, and when the pressure inside the battery cell increases, the CID is cut off to prevent current from flowing through the battery cell, thereby safely preventing overcharge of the battery.

However, when the battery cells are connected in parallel, if the CID of a specific battery cell operates, the connection of the corresponding defective battery cell is disconnected, and an overcurrent flows in the remaining normal battery cells connected in parallel to the defective battery cell due to the current flowing through the defective battery cell, so that an overload occurs on the normal battery cells. In addition, even when disconnection of a specific cell occurs in parallel-connected cells due to reasons such as open of parallel connection lines of the specific cell, in addition to the operation of the protection element such as the CID described above, overcurrent flows through the remaining normal cells.

This phenomenon has a problem of promoting deterioration of the battery cell, resulting in reduction of battery performance and life.

(patent document 1) KR10-2018-0034138A

Disclosure of Invention

[ problem ] to provide a method for producing a semiconductor device

The present invention is to solve the above-mentioned problems, and provides a battery cell switching device capable of replacing a corresponding battery cell with a replacement battery cell when a plurality of battery cells are connected in parallel and an open or disconnected parallel connection line of a specific battery cell occurs due to CID operation.

[ technical solution ] A

According to the present invention, a battery pack including at least one parallel row of battery cells formed by arranging a plurality of battery cells in parallel, the battery pack includes: a first cell group configured by connecting a predetermined number of sequentially adjacent battery cells in parallel from a first battery cell among the battery cells constituting the parallel rows of battery cells; and a second cell group configured by connecting in parallel remaining battery cells, except for the battery cell set as the first cell group, among the battery cells constituting the parallel rows of battery cells, wherein the first and second cell groups are electrically separated, wherein, among the battery cells of the second cell group, a battery cell closest to the first cell group is set as a replacement battery cell, wherein, when a failed battery cell occurs in the first cell group, the replacement battery cell is electrically separated from the second cell group and is connected in parallel to the first cell group to replace the failed battery cell.

In addition, the battery pack may further include a switch configured to perform a switching operation to replace the defective battery cell occurring in the first battery cell group with the replacement battery cell, wherein the switch includes: a first switch provided on a first parallel connection line connecting the replacement battery cell of the second battery cell group and the battery cell of the first battery cell group in parallel to control a connection current between the replacement battery cell and the first battery cell group; and a second switch provided on a second parallel connection line connecting the replacement battery cell and the remaining battery cells of the second battery cell group in parallel to control a connection flow between the replacement battery cell and the remaining battery cells.

Further, the battery pack may further include a control unit configured to control switching operations of the first and second switches according to whether a faulty battery cell occurs in the first cell group due to an open parallel connection line or a CID operation.

In the case where a normal state of a failed battery cell does not occur in the first cell line, the control unit turns off the first switch and turns on the second switch, thereby cutting off the connection of the replacement battery cell with the battery cell of the first cell line and connecting the replacement battery cell to the remaining battery cells of the second cell line.

Further, when a defective battery cell occurs in the first cell group, the control unit turns on the first switch and turns off the second switch to separate the replacement battery cell from the second cell group and connect the replacement battery cell to the battery cell of the first cell group, thereby replacing the defective battery cell with the replacement battery cell.

Further, the first cell group operates as a main power source of a device in which a battery pack is mounted, and the second cell group operates as an auxiliary power source of the device.

According to the present invention, a battery cell switching method includes: a battery cell parallel row forming step of arranging a plurality of battery cells in parallel to form a battery cell parallel row; a cell group setting step of connecting a predetermined number of battery cells in parallel in order from a first battery cell among the battery cells constituting the parallel rows of battery cells to set up as a first cell group, and connecting the remaining battery cells except the battery cells set up as the first cell group in parallel to set up as a second cell group; a defective cell detecting step of detecting whether a defective cell occurs in the first cell group due to an open circuit of a parallel connection line or a CID operation; and a defective battery cell replacement step of replacing, when a defective battery cell occurs in the first battery cell group, the defective battery cell with a replacement battery cell belonging to the second battery cell group.

Specifically, the defective battery cell replacing step may include: a replacement battery cell separation step of electrically separating the replacement battery cell from the second battery cell group by turning off a second switch provided on a parallel connection line between the replacement battery cell and the remaining battery cells of the second battery cell group; and a replacement battery cell connection step of connecting the replacement battery cells separated from the second battery cell group in parallel to the first battery cell group by turning on a first switch provided on a parallel connection line between the replacement battery cell and the battery cell of the first battery cell group.

Here, among the battery cells of the second cell line, the replacement battery cell is closest to the first cell line.

Further, the first cell group operates as a main power source of a device in which a battery pack is mounted, and the second cell group operates as an auxiliary power source of the device.

[ PROBLEMS ] the present invention

The present invention replaces a specific battery cell, which causes an open circuit or disconnection of parallel connection lines due to CID operation, among parallel-connected battery cells, with a normal replacement battery cell through a switching operation, so that it is possible to prevent safety problems and battery cell degradation problems occurring in the remaining normal battery cells due to the influence of a connection failure of the specific battery cell, and further it is possible to prevent battery performance degradation due to these problems.

Drawings

Fig. 1 is a diagram schematically illustrating a battery pack having a battery cell switching device according to the present invention.

Fig. 2 is a diagram schematically showing an electrical connection state in a normal state of a non-faulty battery cell.

Fig. 3 is a diagram schematically showing an electrical connection state in a state where a faulty battery cell occurs and a switching operation is performed.

Fig. 4 is a flowchart illustrating a battery cell switching method according to the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in various forms and is not limited to the embodiments described herein. In the drawings, portions irrelevant to the description are omitted for clarity of description of the present invention, and like reference numerals denote like elements throughout the specification.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1. Battery pack including cell switching device of parallel-connected cells

Fig. 1 is a diagram schematically showing the overall configuration of a battery pack including a battery cell switching device according to the present invention. Referring to this drawing, a battery pack including a battery cell switching device according to the present invention may include the following configuration.

Referring to fig. 1, in a battery pack 100, a plurality of battery cells 101 are arranged in parallel to form one battery cell parallel row, and at least one battery cell is arranged in parallel and in series. This can be classified and explained as follows.

1.1. First cell group 112

As described above, the plurality of battery cells 101 are arranged in parallel to form one battery cell parallel row, and among the battery cells forming the battery cell parallel row, a predetermined number of adjacent battery cells are grouped in order from a first battery cell, and these battery cells are connected in parallel, the formed group being referred to as a first battery cell group 112 as a main power supply of the battery pack-equipped apparatus.

As shown in fig. 1, the same number of battery cells are divided into first cell groups 112a to 112N for each parallel row of battery cells (first to nth parallel rows of battery cells), and the battery cells constituting the first cell group in one parallel row of battery cells are connected in parallel, and the battery cells of the first cell group in the adjacent parallel row of battery cells are connected in series, so that all the battery cells constituting the first cell group included in the battery pack 100 are electrically connected to each other in a series/parallel state to form one battery module. Here, a battery module configured by connecting at least one first cell group in series is referred to as a first battery module 110.

That is, the battery cells constituting the first cell group 112a in parallel with the first battery cell are connected in series with the battery cells constituting the first cell group 112b in parallel with the second battery cell facing thereto, and the battery cells constituting the first cell group 112N-1 in parallel with the (N-1) th battery cell are connected in series with the battery cells constituting the first cell group 112N in parallel with the nth battery cell, thereby constituting the first battery module 110.

The first battery module 110 configured as described above may be used as a main power source in a device equipped with a battery pack. When the device mounted with the battery pack is, for example, a vehicle, the first battery module 110 serves as a battery module for driving the motor that provides power to drive the motor.

That is, since the first battery module serves as a main power source of the apparatus, it is preferable for the number of battery cells constituting the first cell group 112 to divide most of the battery cells constituting the parallel rows of battery cells into the first cell group.

For example, when one battery cell parallel row is composed of 13 battery cells, at least 8 or more battery cells may be disposed as the first battery cell group.

The first cell stack 112 is electrically separated from a second cell stack 122, which will be described later.

1.2. Second cell group 122

As described above, by connecting the remaining battery cells, excluding the battery cells divided into the first cell line, in parallel in one parallel battery cell line, the remaining battery cells as a group may be referred to as a second cell line. As shown in fig. 1, the same number of battery cells of each parallel row of battery cells are divided into a second cell group 122, the battery cells 101 constituting the second cell group in one parallel row of battery cells are connected in parallel, the battery cells of the second cell group of the adjacent parallel row of battery cells are connected in series, and all the battery cells 101 constituting the second cell groups 122a to 122n included in the battery pack 100 are electrically connected to each other in a series/parallel state to form one battery module. Here, a battery module configured by connecting at least one second cell group in series is referred to as a second battery module 120.

That is, the battery cells constituting the second cell group 122a of the first battery cell parallel row are connected in series with the battery cells constituting the second cell group 122b of the second battery cell parallel row opposite thereto, and the battery cells constituting the second cell group 122N-1 of the (N-1) th battery cell parallel row are connected in series with the battery cells constituting the second cell group 122N of the nth battery cell parallel row, so as to constitute the second battery module 120.

The second battery module 120 configured as described above may be used as an auxiliary power source in a device equipped with a battery pack. When the device mounted with the battery pack is, for example, a vehicle, the second battery module 120 functions as a battery module for driving additional devices, such as an audio device, a navigation device, and a black box, to provide power for driving the additional devices mounted on the vehicle.

That is, since the second battery module serves as an auxiliary power source of the apparatus, it is preferable for the number of battery cells constituting the second cell group to divide a small number of battery cells among the battery cells constituting the parallel rows of battery cells into the second cell group.

For example, when 13 battery cells form one battery cell parallel row, 11 battery cells may be disposed as a first battery cell group, and the remaining two battery cells may be disposed as a second battery cell group. However, the present invention is not limited thereto, and the above is an example for understanding the description, and the first cell group is a main power source of the device, and the configuration ratio of the second cell group may be changed as long as it can sufficiently function as an auxiliary power source of the device.

Generally, for example, when the device is a vehicle, a lead-acid battery is used as a power source for additional devices such as a navigation device, a black box, an audio device, and the like. In contrast, the present invention constitutes the second cell group instead of the existing lead-acid battery, and allows the battery cells constituting the second cell group to be used as a power source for additional devices, which function as the existing lead-acid battery, and sets one of the battery cells as a replacement battery cell. Therefore, it is not necessary to separately prepare a new replacement battery cell, thereby simplifying the circuit configuration, and since the replacement battery cell is also used as a power source, even if a defective battery cell used as a main power source is replaced with a replacement battery cell, it is possible to maintain SOH more consistent with the remaining normal battery cells of the first cell line than with the individual unused battery cells. Therefore, the life management efficiency of the battery cell can be improved.

A. Replacement battery unit 1222

In a specific battery cell among the battery cells constituting the first cell line 112, when a connection failure occurs due to an open circuit of the parallel connection lines or a CID operation, the replacement battery cell may function to replace the failed battery cell.

The replacement battery cell may be provided as any one of the battery cells constituting the second cell group 122.

For example, as shown in fig. 1, among the battery cells of the second cell line 122, the battery cell closest to the battery cell of the first cell line 112 may be provided as the replacement battery cell 1222. In this case, the defective battery cell occurring in the first battery cell group may be replaced with a replacement battery cell having a non-complicated circuit configuration.

1.3. Switch 130

The switch is a configuration that controls a connection flow such that the replacement battery cell replaces a defective battery cell occurring in the first cell group by operating on/off under the control of a control unit described later, and may include a first switch 132 and a second switch 134.

A. First switch 132

The first switch is provided on a first parallel connection line a connecting the replacement battery cell 1222 of the second battery cell group 122 and the first battery cell group 112 in parallel, and may be configured to control the flow of electrical connection between the battery cell of the first battery cell group 112 and the replacement battery cell 1222 of the second battery cell group 122. Here, as shown in fig. 1, since the first parallel connection lines a are formed at the upper and lower ends of the battery cells, the first switches 132 are also provided at the upper and lower ends of the battery cells.

In a normal state in which no faulty cell has occurred in the first cell group 112, the first switch 132 is controlled to an off state, and as shown in fig. 2, the flow of electrical connection between the first cell group 112 and the replacement cell 1222 is cut off.

Thereafter, for example, when a faulty battery cell occurs in the first cell group 112a of the first cell group parallel row, the first switch 132a in the first cell group parallel row is controlled to an on state, and as shown in fig. 3, the replacement battery cell 1222a may perform its function as a member of the first cell group 112 by interrupting the flow of electrical connection between the battery cell of the first cell group 112a and the replacement battery cell 1222 a.

B. Second switch 134

The second switch is provided on the second parallel connection line b connecting the replacement battery cell 1222 of the second cell group 122 and the remaining battery cells in parallel, and may be a configuration for controlling a connection flow between the replacement battery cell 1222 of the second cell group 122 and the remaining battery cells. Here, as shown in fig. 1, when N parallel rows of battery cells are arranged in the battery pack, the second parallel connection lines b are formed only at the upper ends of the battery cells in the first to (N-1) th parallel rows of battery cells, and at the upper and lower ends of the battery cells in the nth parallel row of battery cells located at the bottom. Therefore, only one second switch 134 is provided for each of the first through (N-1) th parallel rows of battery cells, but the second switches 134 are provided at both the upper and lower ends of the battery cells in the Nth parallel row of battery cells.

In a normal state in which no faulty battery cell has occurred in the first cell group 112, the second switch 134 is controlled to be in an on state, and as shown in fig. 2, the replacement battery cell 1222 of the second cell group 122 and the remaining battery cells are electrically connected to each other such that the replacement battery cell 1222 functions as a member of the second cell group 122.

Then, as shown in fig. 3, for example, when a faulty battery cell occurs in the first cell group 112a of the first battery cell parallel row, the second switch 134a of the first battery cell parallel row is controlled to an off state, the second switch 134b of the second battery cell parallel row is controlled to an on state, and when the replacement battery cell 1222a of the second cell group 122a is disconnected from the second cell group 122a by cutting off an electrical connection current between the replacement battery cell 1222a and the remaining battery cells, the remaining battery cells constituting the second battery module 120 may be electrically connected to each other in a series/parallel state.

C. Third switch 136

As shown in fig. 1, in the case where N parallel rows of battery cells are arranged in the battery pack 100, in the parallel rows of battery cells other than the first and nth parallel rows of battery cells among the first to nth parallel rows of battery cells, that is, in the second to (N-1) th parallel rows of battery cells, each battery cell of the second cell group is connected in series with each battery cell of the second cell group of the adjacent parallel rows of battery cells, and in this case, a third switch 136 for controlling the connection flow may be additionally provided on the series connection line c.

The third switch 136 may cut off the connection between the replacement battery cell connected in parallel to the first cell line 112 to replace the failed battery cell and the remaining battery cells of the second battery module 120.

Initially, all the third switches 136 are controlled to an on state to connect the replacement battery cells arranged in each of the parallel rows of battery cells in series with each other, and for example, if a defective battery cell occurs in the first cell group 112a of the first parallel row of battery cells, the third switch 136a disposed on the series connection line c between the replacement battery cell 1222a of the first parallel row of battery cells and the replacement battery cell 1222b of the second parallel row of battery cells is controlled to an off state to block the flow of electrical connection.

1.4. Control unit (not shown)

The control unit is a configuration that controls the on/off of the first switch 132, the second switch 134, and the third switch according to whether or not the external faulty battery cell detection system detects a faulty battery cell, and allows the replacement battery cell 1222 of the second battery cell group 122 to replace the faulty battery cell occurring in the first battery cell group 112.

< example 1: when arranging the individual cells in parallel rows >

Specifically, as described above, in the normal state in which no faulty cell has occurred in the first cell group 112, by controlling the first switch 132 to the off state and the second switch 134 to the on state, the first cell group 112 and the second cell group 122 may be electrically separated, and the replacement cell 1222 may be used as a member of the second cell group 122.

In this state, when a control signal indicating that a defective battery cell occurs in the battery cells belonging to the first cell group 112 due to an open circuit of parallel connection lines or a CID operation is received from the external defective battery cell detection system, the first switch 132, which is configured on the parallel rows of the battery cells including the first cell group 112 to which the corresponding defective battery cell belongs, is controlled to an on state, and the second switch 134 is controlled to an off state, based on the control signal, so that the replacement battery cell 1222 may serve as a member of the first cell group 112 by replacing the corresponding defective battery cell by separating the replacement battery cell 1222 from the second cell group 122 and allowing the replacement battery cell 1222 to be included in the first cell group 112.

< example 2: when a plurality of battery cells are arranged in parallel row >

As shown in fig. 1, when a plurality of cells are arranged in parallel in N, the above-described third switch 136 may be additionally controlled.

In the case of embodiment 2, in a normal state in which no faulty battery cell occurs, all the first switches 132 of the battery pack are controlled to an off state, the second switch 134a of the first battery cell parallel row and the second switch 134N located at the lower end of the nth battery cell parallel row are controlled to an on state, and the remaining second switches are controlled to an off state, and further, the third switch 136 may be controlled to an on state to electrically connect the battery cells constituting the second battery cell group of each battery cell parallel row to each other in a series/parallel state.

Thereafter, for example, if a faulty battery cell occurs in the first cell group 112a of the first parallel battery cell row, the first switch 132a of the first parallel battery cell row is controlled to an on state, the second switch 134a is controlled to an off state, and the third switch 136a is controlled to an off state, so that the replacement battery cell 1222a of the first parallel battery cell row is separated from the second battery module 120 and connected in parallel to the first cell group 112a, thereby allowing the replacement battery cell 1222a to function as a component of the first battery module 110. In addition, the remaining battery cells constituting the second battery module 120 may be electrically connected to each other in a series/parallel state by switching the second switch 134b of the second battery cell parallel row, which is the next row of the first battery cell parallel row, to an on state.

Here, the external faulty battery cell detection system is, for example, the manner disclosed in korean patent application nos. 10-2019 and 0122268 and 0122269 filed by the present applicant, and may be configured as a system for detecting the occurrence of faulty battery cells due to the open of parallel connection lines or CID operation.

The control signal from the external faulty battery cell detection system configured as described above may include, for example, a cell group identification number or a parallel-row battery cell identification number to identify, in the first battery module 110 included in the battery pack 100, the first cell group or the parallel row battery cell to which the faulty battery cell belongs.

For example, when a faulty battery cell occurs in the first cell group 112a included in the first parallel row of battery cells, the control signal from the external faulty battery cell detection system includes a first parallel row of battery cells identification number or a corresponding first cell group 112a identification number. The control unit receiving the transmission identifies the failed battery cell in the first cell group 112a belonging to the first parallel battery cell row based on the control signal. Therefore, by controlling the first switch 132a located on the first cell parallel row to be turned on and the second switch 134a to be turned off, as shown in fig. 3, the replacement battery cell 1222a can be replaced for use by replacing a failed battery cell.

In this way, the present invention can replace a failed battery cell by replacing the failed battery cell with a normal replacement battery cell through a simple switching operation if a case of the failed battery cell occurs due to an open circuit of parallel connection lines or a CID operation, among the parallel battery cells. Accordingly, it is possible to prevent the normal battery cell from being overloaded when overcurrent flows to the remaining normal battery cells connected in parallel with the failed battery cell due to the current flowing through the failed battery cell. Therefore, it is possible to fundamentally solve the problem of the degradation of the performance and life of the battery due to the promotion of the degradation of the remaining normal battery cells.

In addition, the present invention does not separately provide a replacement battery cell as an unused new battery cell, but instead, sets a battery cell, which serves as a power source for additional equipment installed in the equipment, as a replacement battery cell, instead of an existing lead-acid battery. Therefore, it is possible to balance the battery cells of the first cell line used as a power source and the degree of deterioration of the battery cells, i.e., SOH, as compared to the unused battery cells. Therefore, an effect of maintaining more uniform life of the battery cell may be brought about.

2. Battery cell switching method (see FIG. 4)

The battery cell switching method of parallel battery cells according to the present invention may include the following steps.

2.1. Parallel row forming step S100 of battery cells

The cell parallel row forming step is a step of forming one cell parallel row by arranging a plurality of battery cells 101 in parallel.

As shown in fig. 1, one or more of the parallel rows of battery cells may be arranged in a battery pack 100, and in this case, the battery cells constituting one parallel row of battery cells are connected in series with the battery cells constituting an adjacent parallel row of battery cells.

In this case, not all of the battery cells constituting the parallel rows of battery cells are electrically connected in parallel, and not all of the battery cells constituting one parallel row of battery cells are electrically connected in series with all of the battery cells constituting the parallel rows of adjacent battery cells, the battery cells are classified according to their functions/functions, and are electrically interconnected in a series/parallel connection state. This will be described in detail in a cell group setting step described later.

2.2. Cell group setting step S200

In order to distinguish between a main power supply and an auxiliary power supply for a device having a battery pack, among battery cells constituting parallel rows of battery cells, a predetermined number of sequentially adjacent battery cells are connected in parallel, starting from a first battery cell, to be set as one group, i.e., a first battery cell group 112, and the remaining battery cells are connected in parallel to be set as one group, i.e., a second battery cell group 122, the first battery cell group 112 and the second battery cell group 122 being electrically separated.

Meanwhile, among the battery cells constituting the second cell group 122, the battery cell closest to the first cell group 112 is configured as the replacement battery cell 1222.

As described above, the replacement battery cell refers to a battery cell that is electrically separated from the second cell stack 122 and connected to the first cell stack to replace a failed battery cell when the failed battery cell occurs due to an open circuit of parallel connection lines or a CID operation in the first cell stack 112.

As described above, based on the replacement battery cell 1222, the first switch 132 is disposed on the parallel connection line a between the replacement battery cell and the battery cell of the first battery cell group 112, and the second switch 134 is disposed on the parallel connection line b between the replacement battery cell and the remaining battery cell of the second battery cell group 122, so that the replacement battery cell 1222 is electrically separated from the first battery cell group 112 by the first switch 112 and the second switch 122 and is connected to the second battery cell group 122 to serve as a member of the second battery cell group 122 in a normal state in which a faulty battery does not currently occur in the first battery cell group 112.

Meanwhile, when there are more than one parallel battery cells, the same number of battery cells are disposed as the first cell group 112a to 122N for each parallel battery cell (first to nth parallel battery cells), as shown in fig. 1, in which the battery cells constituting the first cell group are connected in parallel and the battery cells of the first cell group of the parallel adjacent battery cells are connected in series, so that the first battery module 110 is configured by electrically connecting all the battery cells constituting the first cell group 112a to 112N included in the battery pack 100 to each other in a series/parallel state.

In addition, the battery cells constituting the second cell group 122 in the parallel rows of the battery cells are also connected in parallel, and the battery cells of the second cell group of the adjacent parallel rows of battery cells (the first to nth battery cells are parallel rows) are connected in series, so that the second battery module 120 is configured by electrically connecting all the battery cells constituting the second cell groups 122a to 122N included in the battery pack 100 to each other in a series/parallel state.

The first cell groups 112a to 112n of the first battery module 110 configured as described above may be used as a main power supply in a battery pack-equipped apparatus. When the device in which the battery pack is mounted is, for example, a vehicle, the first cell group 112a to 112n of the first battery module functions as a battery module of a driving motor that supplies electric power for driving the motor.

Meanwhile, the second cell groups 122a to 122n of the second battery module 120 may be used as auxiliary power sources in the device in which the battery pack is mounted. When the device is, for example, a vehicle, the second cell groups 122a to 122n of the second battery module serve as battery modules for driving additional devices, such as an audio device, a navigation device, and a black box, that provide power for driving the additional devices mounted on the vehicle.

Therefore, when the first and second cell stacks are disposed, it is preferable to dispose more battery cells than the second cell stack 122 as the first cell stack 112 among the battery cells in parallel rows.

2.3. Faulty battery cell detection step S300

The defective cell detecting step is a step of detecting whether a defective cell occurs due to an open circuit of the parallel connection lines or a CID operation in the cells included in the first cell group 112 set in the cell group setting step S200.

As described above, detecting whether a faulty battery cell occurs among the battery cells of the first cell group 112 connected in parallel may be performed by an external faulty battery cell detection system, and when a faulty battery cell is detected, a control signal indicating the faulty battery cell is transmitted to a control unit (not shown), so that the control unit may recognize that a faulty battery cell occurs in the first cell group 112.

In this case, the control signal received by the control unit (not shown) from the external faulty battery cell detection system may include, for example, a cell group identification number or a parallel battery cell row identification number to identify, among the first battery modules included in the battery pack, the first cell group or the parallel battery cell row to which the faulty battery cell belongs.

Here, the external faulty battery cell detection system is, for example, in the manner disclosed in korean patent application nos. 10-2019 and 10-2019 through 0122268 and 10-2019, which are filed by the present applicant, and may be configured as a system for detecting faulty battery cells due to an open parallel connection line or a CID operation.

2.4. Failed battery cell replacement step S400

The defective cell replacing step is a step of electrically separating the replacement battery cell 1222 from the second cell stack 122 and connecting in parallel to the first cell stack 112 to replace the defective battery cell, when the defective cell occurs due to the open of the parallel connection lines or the CID operation among the battery cells of the first cell stack 112 is detected in the defective cell detecting step S300.

The defective battery cell replacing step may include the following steps.

A. Replacement cell separation step S410

The replacement battery cell separation step is a step of electrically separating the replacement battery cell 1222 from the second cell group 122.

This step electrically separates the replacement battery cell 1222, which initially operates as a member of the second cell group 122, from the second cell group 122, and may be implemented by turning off the second switch 134 provided on the parallel connection line b between the replacement battery cell 1222 and the remaining battery cells of the second cell group 122.

B. Replacement battery cell connection step S420

The replacement-battery-unit connecting step is a step of connecting the replacement battery unit 1222 in parallel to the first battery cell group 112 to replace the failed battery cell, after electrically separating the replacement battery cell from the second battery cell group 122 in the replacement-battery-unit separating step S410.

This step may be implemented by turning on the first switch 132 disposed on the parallel connection line a between the replacement battery cell 1222 and the battery cell of the first cell group 112.

Through these steps, the replacement battery cell 112, which originally serves as a member of the second cell group 122, is electrically separated from the second cell group 122 and connected in parallel to the first cell group 112, so that the replacement battery cell 1222 may operate as a member of the first cell group 112 by replacing a defective battery cell generated in the first cell group 112.

For example, when a faulty battery cell occurs in the first cell group 112a included in the first parallel battery cell row, the control unit (not shown) receiving a control signal from the external faulty battery cell detection system controls the first switch 132a located on the first parallel battery cell row to an on state and controls the second switch 134a to an off state. Therefore, as shown in fig. 3, while the replacement battery cell 1222a is electrically separated from the second cell stack 122a and electrically connected in parallel with the battery cells of the first cell stack 112a, the replacement battery cell 1222a replaces the failed battery cell to serve as a member of the first cell stack 112 a.

On the other hand, although the technical idea of the present invention is specifically described according to the above embodiments, it should be noted that the above embodiments are for the purpose of explanation and not limitation. In addition, those skilled in the art of the present invention will appreciate that various embodiments are possible within the spirit of the present invention.