KR20220045616A - Battery module with abnormal detecting function, and Abnormal detecting method - Google Patents

Abstract

The present invention relates to a battery module with an abnormality detection function to easily identify defects in connections, and an abnormality detection method thereof. More specifically, the battery module comprises: a battery cell including an electrode assembly and an electrode lead protruding from the electrode assembly; a plurality of bus bars connecting two or more battery cells; a connection bus bar connecting the plurality of bus bars; and a module case accommodating the battery cell, the bus bars, and the connection bus bar. A sensing unit capable of checking a connection state between the bus bars and the connection bus bar is provided inside the module case.

Description

A battery module with abnormality detecting function and a method for detecting abnormality in a battery module {Battery module with abnormal detecting function, and Abnormal detecting method}

The present invention relates to a battery module having an abnormality detection function and a method for detecting abnormality in a battery module, specifically, a connection part between an electrode lead and a bus bar, and a connection part between the busbar and a connection busbar connecting the busbar are normally connected. To a battery module equipped with an abnormality detection function capable of detecting whether there is an abnormality, and a method for detecting abnormality of the battery module.

Rechargeable batteries, which are used as energy sources for various electronic devices that are indispensable in modern society, are increasing in capacity due to the increase in usage and complexity of mobile devices, and the development of electric vehicles. A plurality of battery cells are disposed in a small device to satisfy a user's demand, but a battery module electrically connecting a plurality of battery cells or a battery pack having a plurality of such battery modules is used in automobiles and the like.

The battery module improves capacity and output by connecting a plurality of battery cells in series and parallel to each other, and in this case, the battery module includes a bus bar for electrical connection between the battery cells and a connection bus bar for connecting between the plurality of bus bars it is common to do

1 is a plan view of a battery module according to the prior art. As shown in FIG. 1, in the conventional battery module, the battery cell 10 including the cell case 11 in which the electrode assembly is accommodated, the positive lead 12 and the negative lead 13 protruding from the electrode assembly are serial or It is arranged in parallel, and two or more battery cells 10 are electrically connected by a bus bar 20 . In addition, the bus bars 20 positioned adjacent to each other are connected by a connecting bus bar 30 to constitute one battery module.

Here, the bus bar 20 and the connecting bus bar 30 are generally connected to each other by bonding, bolting, or fitting.

However, due to the change in the positions of the battery cells 10 due to external impact or swelling, the coupling force of the connection portion A, which is the portion where the bus bar 20 and the connection bus bar 30 are connected, is weakened, and as a result, the connection portion A ) may be reduced.

When the area of the connection portion A is reduced as described above, the resistance at the connection portion A increases and the temperature increases, which may lead to ignition or explosion of the battery module.

Patent Document 1 discloses that the temperature of a battery cell is detected using an infrared temperature sensor to detect a battery cell in which an abnormality has occurred inside the battery module, but does not disclose whether the connection between the bus bar and the connecting bus bar is defective. not.

Japanese Patent Publication No. 06157988 (2017.07.05)

The present invention is to solve the above problems, and to provide a battery module equipped with an abnormality detection function capable of confirming whether a connection between a bus bar and a connection bus bar inside the battery module is abnormal and a method for detecting abnormality of the battery module aim to

A battery module according to the present invention for achieving the above object includes an electrode assembly, a battery cell including an electrode lead protruding from the electrode assembly, a plurality of bus bars connecting two or more battery cells, and the plurality of bus bars A connecting bus bar to be connected and a module case for accommodating the battery cell, the bus bar and the connecting bus bar, wherein a sensing unit for checking a connection state between the bus bar and the connecting bus bar is provided inside the module case do it with

Also, in the battery module according to the present invention, the sensing unit is a temperature sensor for measuring a temperature of a connection portion between the bus bar and the connection bus bar.

In addition, in the battery module according to the present invention, the temperature sensor is characterized in that the non-contact temperature sensor.

In addition, in the battery module according to the present invention, when the temperature measured by the temperature sensor is out of a set range, a buzzer that generates a warning sound is further provided outside the module case.

In addition, the method for detecting whether a battery module is abnormal according to the present invention includes the steps of: (S1) measuring a temperature of a connection portion between the bus bar and the connecting bus bar; (S2) comparing the measured temperature with a set temperature range; and (S3) determining that the measured temperature is within a set temperature range as normal, and judging as an abnormal state when out of the set temperature range.

In addition, in the method for detecting whether the battery module is abnormal according to the present invention, the abnormality is characterized in that the battery module is inspected before shipment.

In addition, in the method for detecting whether the battery module is abnormal according to the present invention, the abnormality is characterized in that the battery module is used in the use step.

In addition, in the method for detecting whether a battery module is abnormal according to the present invention, the step (S1) of measuring the temperature of a connection portion between the bus bar and the connection bus bar is performed continuously.

In addition, in the method for detecting whether the battery module is abnormal according to the present invention, when the measured temperature is out of a set temperature range and in an abnormal state, the step (S4) of generating a warning sound is further performed.

In addition, in the method for detecting whether the battery module is abnormal according to the present invention, when the measured temperature is out of the set temperature range and in an abnormal state, the step (S4) of cutting off the power supplied to the battery module may be further performed. .

The present invention may be a battery pack including the above-mentioned battery module, and may also be a device in which the battery module is mounted.

In the present invention, one or two or more components that do not conflict among the above components may be selected and combined.

As described above, according to the battery module provided with an abnormality detection function and the abnormality detection method of the battery module of the present invention, it is possible to constantly measure the temperature change of the connection part between the busbar and the connection busbar inside the module case. Since the detection unit is provided, there is an advantage in that it is possible to easily determine whether the connection unit is defective.

In addition, according to the battery module equipped with an abnormality detection function of the present invention and the abnormality detection method of the battery module, when the temperature of the connection part falls within an abnormal range, it informs the administrator or cuts off the supplied power to prevent ignition or explosion in advance. It has the advantage of being able to prevent it.

1 is a plan view of a battery module according to the prior art.
2 is a plan view of a battery module according to a first preferred embodiment of the present invention.
3 is a plan view of a battery module according to a second preferred embodiment of the present invention.
4 is a plan view of a battery module according to a third preferred embodiment of the present invention.
5 is a flowchart for explaining a method of detecting whether a battery module is abnormal according to the present invention.

Hereinafter, embodiments in which those of ordinary skill in the art to which the present invention pertains can easily practice the present invention will be described in detail with reference to the accompanying drawings. However, when it is determined that a detailed description of a related well-known function or configuration may unnecessarily obscure the gist of the present invention in describing the operating principle of the preferred embodiment of the present invention in detail, the detailed description thereof will be omitted.

In addition, the same reference numerals are used throughout the drawings for parts having similar functions and functions. Throughout the specification, when it is said that a certain part is connected to another part, it includes not only a case in which it is directly connected, but also a case in which it is indirectly connected with another element interposed therebetween. In addition, the inclusion of any component does not exclude other components unless otherwise stated, but means that other components may be further included.

In addition, descriptions that limit or add elements may be applied to all inventions unless there are special limitations, and are not limited to specific inventions.

Also, throughout the description and claims of the present application, the singular includes the plural unless otherwise indicated.

Also, throughout the description and claims herein, "or" is intended to include "and" unless stated otherwise. Therefore, "comprising A or B" means all three cases including A, including B, or including A and B.

2 is a plan view of a battery module according to a first preferred embodiment of the present invention. As shown in FIG. 2 , the battery module according to the first embodiment of the present invention includes a plurality of battery cells 100 , a bus bar 200 , a connection bus bar 300 , a module case 400 , and a sensing unit. (500) is included.

First, if the battery cell 100 is described in detail, the battery cell 100 is a cell case 110 for accommodating an electrode assembly, and a positive lead ( 120 ) and a negative lead 130 .

Here, the electrode assembly is a jelly-roll type assembly having a structure in which a separator is interposed between a long sheet-shaped positive electrode and a negative electrode and then wound, or a rectangular positive electrode and a negative electrode are stacked with a separator interposed between unit cells A stack-type assembly consisting of a stack-folding assembly in which unit cells are wound by a long separation film, or a lamination-stack-type assembly in which unit cells are stacked with a separator interposed therebetween and attached to each other. However, it is not limited thereto.

The cell case 110 for accommodating the electrode assembly typically has a laminate sheet structure of an inner layer/metal layer/outer layer. Since the inner layer is in direct contact with the electrode assembly, it must have insulation and electrolyte resistance, and for sealing with the outside, the sealing property, that is, the sealing portion where the inner layers are thermally bonded to each other must have excellent thermal bonding strength. The material of the inner layer may be selected from polyolefin resins such as polypropylene, polyethylene, polyethylene acrylic acid, polybutylene, etc., polyurethane resins and polyimide resins having excellent chemical resistance and good sealing properties, but is not limited thereto, Polypropylene excellent in mechanical properties such as tensile strength, rigidity, surface hardness, and impact resistance and chemical resistance is the most preferable.

The metal layer in contact with the inner layer corresponds to a barrier layer that prevents moisture or various gases from penetrating into the battery from the outside.

And an outer layer is provided on the other side of the metal layer, and this outer layer can be made of a heat-resistant polymer with excellent tensile strength, moisture permeability and air permeability prevention so as to secure heat resistance and chemical resistance while protecting the electrode assembly. As an example, nylon or polyethylene terephthalate may be used, but is not limited thereto.

On the other hand, the electrode leads composed of the positive electrode lead 120 and the negative electrode lead 130 may have a structure in which the positive electrode tab and the negative electrode tab of the electrode assembly are electrically connected to each other and then exposed to the outside of the case, and without the positive electrode tab and the negative electrode tab The electrode lead may have a structure that directly connects the electrode assembly and the outside of the cell case, but is not limited thereto. Since the battery cell 100 as described above corresponds to generally known configurations, a more detailed description thereof will be omitted.

On the other hand, in order to meet the required capacity or output, a plurality of the above-described battery cells 100 are generally stacked side by side in a horizontal or vertical direction, and in this case, a bus bar to electrically connect these battery cells 100 to each other. (200) is provided.

The bus bar 200 connects the battery cells 100 in series or parallel, for example, as shown in FIG. A plurality of bus bars 200 may be mounted.

Here, the aforementioned leads and the bus bar 200 may be connected to each other through a known fixing means, for example, laser welding, resistance welding, or the like so that they can be firmly fixed to each other. In addition to this, a slit is provided in the bus bar 200, and the lead to be fixed may be fixed by welding after penetrating and bending the slit.

Subsequently, the connection bus bar 300 is configured to electrically connect a plurality of bus bars 200 adjacent to each other. Of course, it is also possible to omit the connection bus bar 300 , but in this case, the number of battery cells 100 accommodated in the battery module due to expansion in the thickness direction (left and right direction in FIG. 2 ) when the battery cell 100 swells. It is more preferable that the connection bus bar 300 is provided because it may be limited.

Here, the bus bar 200 and the connecting bus bar 300 may employ various means such as screw coupling in addition to laser welding and resistance welding, which are means for fixing the leads and the bus bar 200 .

Meanwhile, in FIG. 2 , after four battery cells are connected in parallel, it is illustrated that they are connected in series with four battery cells located adjacent to each other, but this is only an example and all battery cells may be connected to each other in parallel. is self-evident

The plurality of battery cells 100 , the bus bar 200 , and the connecting bus bar 300 described above are accommodated in the module case 400 to be protected from external shocks and the like. As an example, the module case 400 may be composed of a lower case having a predetermined space in which the lower part and the side surfaces are surrounded by a plate and accommodating the battery cell 100 and the like, and an upper case covering the lower case, if necessary. In some cases, it is also possible to include a flat lower case in which the battery cell 100 is seated, and an upper case in which the side and upper surfaces are sealed to surround the battery cell 100 .

On the other hand, the upper case and the lower case may be fixedly assembled with each other by a known fixing means such as a press fit method, a bolt fastening method, or a welding method.

Next, the sensing unit 500 will be described. The sensing unit 500 is configured to check the connection state between the electrode lead and the bus bar 200 and the connection state between the bus bar 200 and the connection bus bar 300 .

When a welding method is employed in fixing an unintentional assembly defect in the battery module assembly step, for example, the electrode lead and the bus bar 200, and the bus bar 200 and the connecting bus bar 300 to each other, the welding surface Due to various causes, such as foreign substances attached to the surface, there may be cases in which only a part of the surface is welded, or the fastening screw is loosely tightened when connecting the bus bar 200 and the connecting bus bar 300 , etc. It may not be securely fixed.

Of course, even if it is securely fastened at the time of assembly, the connection portion between the electrode lead and the bus bar 200 or the bus bar 200 and the connecting bus bar 300 may be spaced apart due to an external impact during use.

The sensing unit 500 is for monitoring whether the connection between the electrode lead and the bus bar 200 and the bus bar 200 and the connection bus bar 300 is securely connected, and is inside the module case 400 . It is preferable to be provided in the , and it is more preferable to be provided in plurality so that the state of each connection part can be accurately determined.

The sensing unit 500 performing the above function is a temperature sensor capable of detecting a change in temperature between the electrode lead and the bus bar 200 connecting unit, and the bus bar 200 and the connecting bus bar 300 connecting unit.

In general, when a lifting phenomenon occurs or a position is changed in some predetermined areas of the bonding surface of metals, specifically, the connection portion between the electrode lead and the bus bar 200, and the connection portion between the bus bar 200 and the connection bus bar 300, etc. When the area of the parts in contact with each other is reduced, the resistance increases and eventually the temperature rises in the center of the part.

In the module case 400 of the present invention, a non-contact temperature sensor capable of detecting a temperature change between the electrode lead and the bus bar 200 connection part, and the bus bar 200 and the connection bus bar 300 connection part is provided, Therefore, it is possible to constantly observe whether the temperature at these connection parts is outside the set predetermined range, so that it is possible to prevent ignition or explosion of the battery module in advance.

The above-described temperature sensor is more preferably a non-contact temperature sensor that can measure the temperature without contact so that the performance of the battery module is not deteriorated or affected, and if it is a sensor that can measure the temperature in a non-contact type, there is no particular limitation, one example It may be a multi-segment infrared temperature sensor.

Because the multi-segment UV temperature sensor does not need to wait for thermal equilibrium to be achieved, the temperature monitoring speed is fast, and there is a risk of damage or contamination of objects that are moving, rotate or vibrate, objects with rapid temperature changes, or contact with them. It is very advantageous for measuring the temperature of an object with a variable temperature distribution, a surface with a variable temperature distribution, an object with a temperature change upon contact, and an object with low thermal-conductivity.

On the other hand, although not shown in the drawings, when the value measured by the temperature sensor is out of a predetermined range, a notification means for notifying the state of the battery module audibly and visually to an administrator or the like may be additionally provided.

For example, a buzzer (not shown) and/or a flashing light (not shown) that generates a warning sound when the value measured by the temperature sensor is out of a predetermined range is provided outside the module case, so that the administrator can respond quickly, and the battery When the module is remotely managed, it is also possible to transmit a signal to the administrator's portable terminal.

In addition, a separate control unit (not shown) is provided to determine whether the value measured by the temperature sensor falls within a predetermined range, and when it is out of the predetermined range, a separate control unit (not shown) is provided, or a battery management system (Battery) It is also possible to design a management system (BMS) to perform the above functions.

3 is a plan view of a battery module according to a second preferred embodiment of the present invention. In the second preferred embodiment of the present invention, except that the connection bus bar 300 is excluded, the rest are the same as in the first embodiment. That is, when the battery cells constituting the battery module are connected only by the bus bar, only the sensing unit 500 capable of observing the temperature change of the leads, the bus bar, and the connection unit may be provided.

4 is a plan view of a battery module according to a third preferred embodiment of the present invention. In the third preferred embodiment of the present invention, the rest is the same as in the first embodiment, except that only the connection bus bar 300 is provided with the sensing unit 500 .

5 is a flowchart for explaining a method of detecting whether a battery module is abnormal according to the present invention.

With respect to the method for detecting whether the battery module is abnormal according to the present invention, the description will be focused on the first preferred embodiment.

The method of detecting whether the battery module is abnormal includes the steps of (S1) measuring the temperature of the connection part between the bus bar 200 and the connecting bus bar 300, (S2) comparing the measured temperature with a set temperature range; (S3) If the measured temperature is within the set temperature range, it is determined as normal, and if it is outside the set temperature range, it is determined as an abnormal state. can be

Specifically, in step (S1), the temperature of the connection portion between the electrode lead and the bus bar 200 and the connection portion between the bus bar 200 and the connection bus bar 300 is measured in a non-contact manner.

The measurement in step (S1) may be an inspection step before shipment of the battery module, and/or a step of using the battery module.

Of course, it is obvious that the measured value may be transmitted to a control unit (not shown) or a battery management system (BMS).

Step (S2) is a step of comparing and determining whether the temperature value measured in step (S1) is within a preset normal range.

If the measured temperature is within the set temperature range, the measured temperature is determined to be normal and the temperature is continuously measured.

Step (S4) is a step of transmitting various abnormal signals in the case of an abnormal state. Separately to generate a warning sound, operate a flashing lamp, transmit a signal to the manager's portable terminal, or cut off the power supplied to the corresponding battery module. of the control unit (not shown) or a battery management system (BMS) controls to transmit a signal.

Of course, it is obvious that the above-described warning sound, blinking light operation, etc. may be performed alone or simultaneously.

Meanwhile, the present invention includes a battery pack including the aforementioned battery module, and the battery module or battery pack may be applied to a device.

Here, the device is, for example, a notebook computer, a netbook, a tablet PC, a mobile phone, an MP3, a wearable electronic device, a power tool, an electric vehicle (EV), a hybrid electric vehicle (HEV) , a Plug-in Hybrid Electric Vehicle (PHEV), an electric bicycle (E-bike), an electric scooter (E-scooter), an electric golf cart, or a system for power storage. However, it is needless to say that the present invention is not limited thereto.

Those of ordinary skill in the art to which the present invention pertains will be able to perform various applications and modifications within the scope of the present invention based on the above content.

10, 100: battery cell
11, 110: cell case
12, 120: positive lead
13, 130: negative lead
20, 200: bus bar
30, 300: connection bus bar
400: module case
500: sensing unit
A: Connection

Claims (10)

a battery cell including an electrode assembly, an electrode lead protruding from the electrode assembly;
a plurality of bus bars connecting two or more battery cells;
a connection bus bar connecting the plurality of bus bars; and
Including; a module case for accommodating the battery cell, the bus bar and the connecting bus bar;
A battery module, characterized in that a sensing unit for checking a connection state between the bus bar and the connection bus bar is provided inside the module case. The method of claim 1,
The sensor unit is a battery module, characterized in that the temperature sensor for measuring the temperature of the connection portion between the bus bar and the connection bus bar. 3. The method of claim 2,
The temperature sensor is a battery module, characterized in that the non-contact temperature sensor. 3. The method of claim 2,
When the temperature measured by the temperature sensor is out of a set range, a buzzer that generates a warning sound is further provided on the outside of the module case. As a method of detecting the abnormality of the battery module according to any one of claims 1 to 4,
(S1) measuring a temperature of a connection portion between the bus bar and the connection bus bar;
(S2) comparing the measured temperature with a set temperature range; and
(S3) If the measured temperature is within a set temperature range, it is determined as normal, and if it is outside the set temperature range, it is determined as an abnormal state. 6. The method of claim 5,
The abnormality detection method of the battery module, characterized in that performed in the inspection step before shipment of the battery module. 6. The method of claim 5,
The abnormality detection method of the battery module, characterized in that performed in the step of using the battery module. 8. The method of claim 7,
The (S1) step of measuring the temperature of the connection portion between the bus bar and the connecting bus bar is performed continuously. 6. The method of claim 5,
When the measured temperature is out of the set temperature range and in an abnormal state, the step (S4) of generating a warning sound is further performed. 8. The method of claim 7,
When the measured temperature is out of the set temperature range and in an abnormal state, the step (S4) of cutting off the power supplied to the battery module is further performed.

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