Battery pack for preventing overheating misdiagnosis due to ambient temperature and method for preventing misdiagnosis

Abstract

The present invention provides a battery pack and an overheat diagnosis method which perform battery overheat diagnosis by measuring each of an internal temperature and an external temperature of the battery pack from different temperature sensors respectively provided in battery cells, a BMS, and a battery pack case of the battery pack for a predetermined period of time, and comparing the same with a predetermined reference value, in particular, it is possible to determine whether the diagnosed overheating is caused by external factors or internal factors of the battery pack.

Description

Technical Field

[0001] The present invention relates to a technology for detecting battery overheating. In particular, the present invention relates to a battery pack and a detection method for detecting the cause of battery overheating by distinguishing between a temperature increase of the battery itself and a temperature increase due to external environmental factors. Background Art

[0002] Overheating usually occurs due to an increase in the temperature of the battery during battery operation. In this case, it is usually difficult to determine whether the cause is due to an increase in the temperature of the battery itself or an increase in the temperature of the external environment.

[0003] In this regard, in cases such as Patent Document 1, in order to solve the problem of determining temperature abnormality based only on the absolute temperature of the battery cell itself without reflecting any change in the ambient temperature of the battery cell, temperature sensors are respectively installed around the battery cell and on the surface of the battery cell to detect an increase in the ambient temperature even before the temperature of the battery cell rises, thereby quickly diagnosing an abnormal temperature condition of the battery cell by using the difference between the temperature of the battery cell itself and the temperature around the battery cell.

[0004] In the case of Patent Document 2, a technology is disclosed in which the battery pack temperature of a battery pack case is measured to balance the temperatures of battery cells, and only when the battery pack temperature is below an appropriate temperature range, battery cells having a battery cell temperature lower than an average battery cell temperature are heated to balance the battery pack temperature to an appropriate temperature range.

[0005] However, none of the above-mentioned prior arts provides a technique for diagnosing battery overheating by distinguishing whether the battery overheating is due to overheating of the battery cells or to an increase in the temperature of the external environment.

[0006] The following are prior arts related to the present invention. Summary of the invention

[0007] Technical issues

[0008] The present invention provides a method for diagnosing whether overheating is caused by an increase in the temperature of a battery pack due to an increase in the temperature of a battery cell or an increase in the external temperature (this method is not provided in the above-mentioned related art) and a battery pack implementing the diagnosis method.

[0009] Technical Solution

[0010] In order to solve the above-mentioned problems, a battery pack configured to perform overheat diagnosis of the battery pack includes: one or more battery cells; a battery management system (BMS), the BMS being configured to diagnose overheating of the battery pack based on an increase in the internal temperature of the battery pack or an increase in the external temperature of the battery pack, and determine whether the cause of the overheat diagnosis is due to the increase in the internal temperature of the battery pack or the increase in the external temperature; a battery pack case, the battery pack case being configured to accommodate the battery cells and the BMS; one or more battery cell temperature sensors, the one or more battery cell temperature sensors being arranged adjacent to the battery cells and being configured to provide measurement values ​​for determining the increase in the internal temperature of the battery pack; and one or more battery pack temperature sensors, the one or more battery pack temperature sensors being attached to the inner surface or the outer surface of the battery pack case and being configured to provide measurement values ​​for determining the increase in the external temperature of the battery pack.

[0011] Here, the BMS may be configured to receive measurement values ​​from the battery cell temperature sensor at a predetermined time period so as to determine an increase in the internal temperature of the battery pack, and to receive measurement values ​​from the battery pack temperature sensor at a predetermined time period so as to determine an increase in the external temperature of the battery pack, and may be configured to receive measurement values ​​from the battery cell temperature sensor and the battery pack temperature sensor so as to calculate the battery pack internal temperature and the battery pack external temperature based on the measurement values, and to perform overheating diagnosis of the battery pack based on the battery pack internal temperature value and the battery pack external temperature value, wherein, if the external temperature value of the battery pack increases earlier than the internal temperature value of the battery pack so that the overheating is diagnosed, it may be determined that the cause of the overheating diagnosis is caused by external factors of the battery pack.

[0012] In addition, the battery pack according to the present invention may further include a BMS temperature sensor disposed adjacent to the BMS, wherein the BMS may be configured to receive measurement values ​​from the cell temperature sensor and the BMS temperature sensor at a predetermined period of time so as to determine an increase in the internal temperature of the battery pack. The battery pack temperature sensor according to the present invention may be mounted on an inner surface or an outer surface of the battery pack housing, and when the battery pack temperature sensor is mounted on the outer surface, the battery pack housing may be provided with a temperature measurement hole at a position corresponding to a portion to which the battery pack temperature sensor is attached, and a heat dissipation film may be attached to a top surface of the battery pack temperature sensor facing the inner surface of the battery pack housing to block heat.

[0013] In addition, the present invention provides a system for diagnosing overheating of a battery pack, the system comprising: one or more of the above-mentioned battery packs; and an upper-level controller configured to receive the internal temperature of the battery pack and the external temperature of the battery pack from the battery pack so as to perform overheating diagnosis of the battery pack. When diagnosing overheating of the battery pack, the upper-level controller may be configured to determine that the overheating is caused by an external factor of the battery pack when the external temperature of the battery pack rises to a value higher than a predetermined reference value earlier than the internal temperature of the battery pack.

[0014] In addition, the present invention provides a method for diagnosing overheating of a battery pack, the method comprising: a battery pack internal temperature measurement process, wherein the battery pack internal temperature measurement process measures the internal temperature of the battery pack during a predetermined period; a battery pack external temperature measurement process, wherein the battery pack external temperature measurement process measures the external temperature of the battery pack during a predetermined period; a battery pack overheat diagnosis process, wherein the battery pack overheat diagnosis process diagnoses whether the battery pack is overheated based on the battery pack internal temperature and the battery pack external temperature; and an overheat diagnosis cause determination process, wherein the overheat diagnosis cause determination process determines that the overheat diagnosis is misdiagnosed when the external temperature of the battery pack rises earlier than the internal temperature of the battery pack during the overheat diagnosis process.

[0015] Here, in the overheat diagnosis process, when the internal temperature of the battery pack is greater than the predetermined reference value, the overheat may be diagnosed as overheating of the battery pack, and in the overheat diagnosis cause determination process, when the external temperature of the battery pack increases earlier than the internal temperature of the battery pack, the overheat may be diagnosed as being caused by an increase in the external temperature. Here, the battery pack internal temperature may be acquired from a battery cell accommodated inside a battery pack case of the battery pack or a temperature sensor mounted on a BMS, and the battery pack external temperature may be acquired from a temperature sensor attached to the battery pack case of the battery pack.

[0016] In addition, the present invention provides: a battery pack temperature measurement process, in which each battery pack measures the internal temperature and external temperature of each battery pack; a measurement value receiving process, in which the upper controller receives the measurement values ​​of the internal temperature and external temperature of each battery pack; an overheating diagnosis process, in which the upper controller performs overheating diagnosis of each battery pack based on the received internal temperature and external temperature measurement values ​​of each battery pack; and an overheating diagnosis cause determination process, in which the overheating diagnosis causes determination process determines whether the overheating diagnosis is caused by internal factors or external factors of the battery pack.

[0017] Here, each battery pack measures the internal temperature and the external temperature from different temperature sensors attached to different positions of the battery pack, the internal temperature is obtained from a temperature sensor contained inside a battery pack case of the battery pack or mounted on a BMS, and the external temperature is obtained from a temperature sensor attached to the battery pack case of the battery pack.

[0018] Beneficial Effects

[0019] According to the present invention, the internal temperature and external temperature of the battery pack can be measured from different temperature sensors installed in each battery cell, BMS and battery pack case of the battery pack during a predetermined period, and then compared with a predetermined reference value to perform battery overheating diagnosis, specifically, to determine whether the cause of overheating is due to internal factors or external factors of the battery pack, thereby preventing misdiagnosis of overheating or investigating the cause of overheating so as to improve the efficiency of battery operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following drawings attached to this specification illustrate preferred embodiments of the present invention and are used to further understand the technical spirit of the present invention and the detailed description of the present invention. The present invention should not be interpreted as being limited to the drawings.

[0021] Figure 1 is a diagram showing a structure of a battery pack according to an embodiment of the present invention.

[0022] Figure 2 : is a diagram showing a structure in which a cell temperature sensor according to an embodiment of the present invention is mounted on a battery cell.

[0023] Figure 3 : is a diagram showing a structure in which a BMS temperature sensor is mounted on a BMS according to an embodiment of the present invention.

[0024] Figure 4 1 is a diagram showing a structure of a battery pack case and a structure in which a battery pack temperature sensor is mounted on the battery pack case according to an embodiment of the present invention.

[0025] Figure 5 is a diagram illustrating a structure of an FPCB including a temperature sensor according to an embodiment of the present invention.

[0026] Figure 6 is a block diagram showing a configuration of a system in which a plurality of battery packs are controlled by a superior controller according to the present invention.

[0027] Figure 7 is a flowchart illustrating a method for diagnosing a temperature of a battery pack according to the present invention. DETAILED DESCRIPTION

[0028] Hereinafter, a structure of a battery pack and an overheat diagnosis method according to the present invention will be described with reference to the accompanying drawings.

[0029] 1. Structure of the battery pack (100) according to the present invention

[0030] A battery pack 100 according to the present invention may include a plurality of battery cells 10, a battery management system (BMS) 20 for managing the battery cells, a battery pack case 30 for accommodating the plurality of battery cells and the BMS, one or more first sensors 40 for measuring the temperature of the battery cells, and one or more battery pack temperature sensors 60 for measuring the temperature of the battery pack, and may also include one or more BMS temperature sensors 50 for measuring the temperature of the BMS.

[0031] (1)Battery cells (10)

[0032] The battery pack 100 according to the present invention includes a typical battery cell 10. One or more cell temperature sensors 40 measuring the temperature of the battery cell are mounted on the battery cell 10.

[0033] like Figure 2 As shown, the cell temperature sensor 40 may be attached to the battery cell through an FPCB 70 for mounting a temperature sensor. Figure 2 a is a side cross-sectional view showing a state in which two cell temperature sensors 40 are mounted at different positions of a battery cell 10 by using an FPCB 70 for mounting a temperature sensor, and Figure 2 b is a plan view showing a state where the cell temperature sensor 40 is mounted.

[0034] (2) BMS (20)

[0035] The battery pack 100 according to the present invention includes a typical BMS 20. A BMS temperature sensor 50 for measuring the temperature around the BMS 20 is mounted on a board constituting the BMS 20. Figure 3 As shown in the block diagram of FIG. 1 , the BMS temperature sensor 50 may be disposed around other elements 21 constituting the BMS 20 and ... Figure 3 Detailed circuit diagrams such as connection relationships between components are omitted in the block diagram.

[0036] The BMS 20 according to the present invention adopts a typical BMS in its structure, but its function is to perform the method for diagnosing the temperature of a battery pack according to the present invention.

[0037] The BMS 20 reads the temperature measurement signals at the respective sensor installation positions from the cell temperature sensor 40, the battery pack temperature sensor 60 or the additional BMS temperature sensor 50 to calculate the temperatures of the battery cells, the BMS and the battery pack case based on the read temperature measurement signals. The battery pack case temperature calculated based on the measurement value of the battery pack temperature sensor 60 calculates the ambient temperature outside the battery pack 100.

[0038] The BMS 20 performs overheat diagnosis of the battery pack using the battery cell temperature and the battery pack case temperature or the additional BMS ambient temperature. When overheat is diagnosed, it is determined whether the cause of the overheat diagnosis is due to an increase in the temperature of the internal battery cell or BMS or an increase in the external ambient temperature of the battery pack 100. The following describes a specific procedure and method for determining whether the cause of the overheat diagnosis is due to an increase in the temperature inside the battery pack or an increase in the temperature outside the battery pack.

[0039] (3) Battery pack housing (30)

[0040] like Figure 1 As shown, the battery pack case 30 according to the present invention accommodates a plurality of battery cells 10 and the BMS 20 , and includes one or more battery pack temperature sensors 60 .

[0041] like Figure 4 As shown in FIG. 1 , the battery pack temperature sensor 60 may be attached to the outer surface of the battery pack housing 30 or as shown in FIG. Figure 4 As shown in FIG. 2 , the battery pack temperature sensor 60 may be attached to the inner surface of the battery pack housing 30. When attached to the inner surface or the outer surface, the battery pack temperature sensor 60 may be mounted and attached to the sensor-mounted FPCB 70, such as Figure 4 shown.

[0042] like Figure 4 C and Figure 4 As shown in d, the battery pack case 30 according to the present invention may include a temperature measurement hole 31. The temperature measurement hole 31 is defined to correspond to the attachment position of the battery pack temperature sensor 60, especially when the battery pack temperature sensor 60 is mounted on the inner surface of the battery pack case 30, and therefore, the battery pack temperature sensor 60 is more affected by the external temperature than by the internal temperature of the battery pack case 30, so that the battery pack temperature sensor 60 is configured to be more sensitive to the external ambient temperature.

[0043] like Figure 4 As shown in c, the top surface of the inner surface of the battery pack housing 30 of the sensor-mounted FPCB 70 facing the battery pack temperature sensor 60, that is, the top surface of the battery pack temperature sensor, can be provided with a heat dissipation film for heat dissipation, so that the battery pack temperature sensor 60 is configured to be less sensitive to the internal temperature of the battery pack housing 30.

[0044] Figure 4 C and Figure 4 d shows a configuration in which a temperature transfer pin 32 is provided in the temperature measurement hole 31 for sealing purposes such as waterproofing or for transferring external temperature. One end of the temperature transfer pin 32 contacts the battery pack temperature sensor 60 attached to the inner surface of the battery pack case, and the other end of the temperature transfer pin 32 is exposed to the outside of the battery pack case 30 through the temperature measurement hole 31 to transfer the external temperature to the battery pack temperature sensor 60.

[0045] exist Figure 4 In d, it is shown that there are holes in the temperature measurement hole 31 and the temperature transfer pin 32, but this is shown for identification in the figure, and in fact, for the shell sealing, the hole between the temperature transfer pin 32 and the inner peripheral surface of the temperature measurement hole 31 can be filled with the same material as the temperature transfer pin 32, the same material as the battery pack shell 30, or a heat transfer material. The temperature transfer pin 32 can be made of a known heat transfer material to better transfer the temperature outside the battery pack shell 30 to the battery pack temperature sensor 60.

[0046] like Figure 4 As shown, the battery pack temperature sensor 60 can be mounted on an FPCB 31 (flexible printed circuit board) having printed wiring for connecting to the BMS20 signal, and the FPCB can be attached to the inner surface or outer surface of the battery pack housing 30 so that the battery pack temperature sensor 60 measures the temperature of the battery pack housing 30.

[0047] (4) Battery cell temperature sensor (40)

[0048] The cell temperature sensor 40 is disposed on the surface of the battery cell 10 to measure the battery cell surface temperature at predetermined periodic intervals, and is connected to transmit a signal for calculating the measured temperature to the BMS.

[0049] The cell temperature sensor 40 may be attached to each surface of the plurality of battery cells 10 to calculate the temperature of each of the plurality of battery cells 10, and as shown in FIG. Figure 2 As shown, individual battery cells 10 can be attached to a plurality of locations.

[0050] (5) BMS temperature sensor (50)

[0051] The BMS temperature sensor 50 is installed on the BMS 20 to measure the ambient temperature. Figure 3 As shown, the BMS temperature sensor 50 is mounted on a printed circuit board (PCB) constituting the BMS 20 to measure the temperature around the BMS 20 .

[0052] The installation position of the BMS temperature sensor 50 according to the present invention is not limited to the BMS PCB, and may be configured to be mounted on a sensor-mounted FPCB 70 and attached around the BMS 20 .

[0053] (6) Battery pack temperature sensor (60)

[0054] As mentioned above Figure 4 As described, one or more battery pack temperature sensors 60 are attached to the inner or outer surface of the battery pack case 30 to measure the temperature outside the battery pack 30 instead of the temperature of the battery cells 10 or the BMS 20 , thereby transmitting the measured value to the BMS 20 .

[0055] (7) Sensor mounted FPCB (70)

[0056] In the present invention, the type of attachment of the first cell temperature sensor to the battery pack temperature sensor is not limited to a specific type. However, as an example of the attachment type, it can be achieved by Figure 5 The sensor-mounted FPCB 70 shown is attached to the inner or outer surface of the battery cell 10, the BMS 20, or the battery pack case 30. Figure 5 Specific circuit patterns are omitted.

[0057] like Figure 5 As shown, the sensor-mounted FPCB 70 forms a sensor mounting portion 73, and the temperature sensor is mounted on the sensor mounting portion 73. The temperature sensor is attached to the sensor mounting portion 73 to form a temperature measuring portion, and the temperature sensor connecting wire 71 of the sensor-mounted FPCB 70 is connected to the conductor pattern of the FPCB 70, and the temperature sensors 40, 50 and 60 are connected to the conductor pattern to transmit the measured value from the sensor to the BMS20, and the measured value of the temperature sensor is transmitted to the BMS. When the sensor-mounted FPCB 70 on which the battery pack temperature sensor 60 is mounted is attached to the outer surface of the battery pack housing 30, the sensor-mounted FPCB 70 is connected inside the battery pack housing 30 to transmit the measured value of the battery pack temperature sensor 60 to the BMS. To this end, a wire connection hole (not shown) for internal connection of the temperature sensor connecting wire 71 may be defined in the battery pack housing 30.

[0058] 2. System 200 for diagnosing overheating of a battery pack

[0059] Figure 6 A configuration of a system 200 for diagnosing overheating of a battery pack is shown, which diagnoses overheating of a battery pack 100 in a battery system including one or more (ie, n) battery packs (100_a, a=1, 2, 3, . . . , n) described above.

[0060] In a system 200 for diagnosing overheating of a battery pack, i.e., a battery system including one or more (i.e., n) battery packs (100_a, a=1, 2, 3, ..., n), as described above, the battery pack 100 measures the temperature inside and outside the battery pack by including a cell temperature sensor or a battery pack temperature sensor, and when diagnosing overheating of each battery pack 100, the BMS 20 of each battery pack 100 uses the measurement value of the cell temperature sensor or the battery pack temperature sensor to determine whether the cause of the overheating diagnosis is due to an increase in the internal temperature of the battery pack 100 or an increase in the external temperature, and then transmits the determined result to the upper controller 210.

[0061] The upper controller 210 may be a controller of a battery rack BMS composed of a plurality of battery packs 100 or a system composed of a plurality of battery packs 100 and a plurality of battery racks.

[0062] In another embodiment, the BMS 20 of the battery pack 100 transmits the temperature measurement value to the upper controller 210, and the upper controller 210 receives the temperature measurement results from each battery pack 100 to perform overheat diagnosis of each battery pack 100, and determines whether the cause of the overheat diagnosis is due to the temperature increase inside the battery pack or the temperature increase outside the battery pack.

[0063] The following describes a specific procedure and method for determining whether the cause of the overheat diagnosis is due to a temperature increase inside the battery pack or a temperature increase outside the battery pack.

[0064] 3. Method for diagnosing overheating of battery pack

[0065] refer to Figure 7 , a method for diagnosing overheat of a battery according to the present invention will be described.

[0066] (1) Battery pack internal temperature measurement process (S10)

[0067] This process is a process in which the battery pack BMS 20 measures the temperature of the battery cell 10 from at least one or more cell temperature sensors 40 attached to the battery cell 10 at predetermined periodic intervals.

[0068] Furthermore, the battery internal temperature measurement process may include a process in which the battery pack BMS 20 measures the BMS temperature from the BMS temperature sensor 50 attached around the BMS 20 in addition to the cell temperature sensor 40 .

[0069] The BMS 20 may calculate a maximum value of the measured temperatures of the battery cells 10 and the BMS as the battery internal temperature to determine overheating by comparing the maximum value with a predetermined first reference value.

[0070] (2) Battery Pack External Temperature Measurement Process (S20)

[0071] This process is a process in which the BMS 20 determines the external temperature of the battery pack using a measurement value from at least one or more battery pack temperature sensors 60 attached to the case 30 of the battery pack 100. The BMS 20 may determine overheating by comparing the external temperature of the battery pack with a predetermined second reference value.

[0072] (3) Battery Pack Overheat Diagnosis Process (S30)

[0073] This process is a process in which the BMS 20 diagnoses overheating of the battery by comparing the internal temperature of the battery measured in operation S10 and the external temperature of the battery pack measured in operation S20 with a predetermined reference value.

[0074] In the battery overheat diagnosis process, if the internal temperature of the battery pack is higher than a predetermined first reference value, or the external temperature of the battery pack is higher than a predetermined second reference value, overheating is diagnosed. The first reference value and the second reference value may be set to be the same or may be set to be different from each other.

[0075] In another embodiment, during the battery overheat diagnosis process, when the internal temperature of the battery pack is not higher than a predetermined first reference value, even if the external temperature of the battery pack is higher than a second reference value, it may not be diagnosed as overheating during a predetermined temperature measurement cycle, and it may be diagnosed as overheating only when the internal temperature of the battery pack is higher than the predetermined first reference value.

[0076] (4) Overheating diagnosis cause determination process (S40)

[0077] The BMS 20 performs operations S10 to S30 at predetermined periodic intervals, and when overheating of the battery is diagnosed in operation S30 for a predetermined period, determines whether the overheating is diagnosed due to an increase in the internal temperature of the battery or an increase in the external temperature of the battery.

[0078] That is, if the external temperature of the battery is higher than a predetermined second reference value, but the internal temperature of the battery is not higher than a predetermined first reference value within a predetermined period of time, even if the battery is determined to be overheated, it is determined that the overheating is not caused by overheating of the battery cell or the BMS but by external factors of the battery, and further, even if the internal temperature of the battery is higher than the predetermined first reference value within a subsequent period of time, it is determined that the battery overheating diagnosis is caused by external factors of the battery, or the overheating diagnosis is misdiagnosed.

[0079] In the battery overheat diagnosis process (S30), in a predetermined temperature measurement cycle, when the internal temperature of the battery pack is not higher than the predetermined first reference value, even if the external temperature of the battery pack is higher than the second reference value, it may not be diagnosed as overheating, and only when the internal temperature of the battery pack is higher than the predetermined first reference value, it can be diagnosed as overheating. However, even in this case, in the overheat diagnosis cause determination process (S40), when the internal temperature of the battery pack is higher than the predetermined first reference value, it is determined that the external temperature of the battery pack rises before the predetermined second reference value, and then, if the internal temperature of the battery pack is higher than the predetermined first reference value, the BMS 20 determines that the cause of the overheat diagnosis is due to external factors of the battery pack.

[0080] like Figure 6 As shown, even in a system where a plurality of battery packs 100a (a=1, 2, 3, . . . , n) are provided and in which the upper controller 210 performs overheat diagnosis of the plurality of battery packs, the method in which the upper controller 210 performs overheat diagnosis of each battery pack is the same. When the BMS 20 of each battery pack receives the overheat diagnosis result or the battery pack internal temperature measurement value and the battery pack external temperature measurement value from each battery pack 100a through operations S10 to S40, the upper controller 210 performs overheat diagnosis on each battery pack and determines the cause of overheating.

[0081] That is, the present invention provides a method for diagnosing overheating of a battery system, the battery system comprising: one or more battery packs, the one or more battery packs being provided with a separate temperature sensor to measure each of an internal temperature and an external temperature of the battery pack; and an upper-level controller, the upper-level controller receiving the internal temperature and the external temperature of each battery pack from the battery pack, and the method comprising: a battery pack temperature measurement process, in which each battery pack measures the internal temperature and the external temperature of each battery pack; a measurement value receiving process, in which the upper-level controller receives the measurement values ​​of the internal temperature and the external temperature of each battery pack; an overheat diagnosis process, in which the upper-level controller performs overheat diagnosis of each battery pack based on the received internal temperature measurement values ​​and the external temperature measurement values ​​of each battery pack; and an overheat diagnosis cause determination process, the overheat diagnosis cause determination process determining whether the overheat diagnosis is caused by internal factors or external factors of the battery pack.

[0082] Here, each battery pack measures the internal temperature and the external temperature from different temperature sensors attached to different positions of the battery pack, the internal temperature is acquired from the battery cells accommodated inside the battery pack case of the battery pack or the temperature sensor mounted on the BMS, and the external temperature is acquired from the temperature sensor attached to the battery pack case of the battery pack. The corresponding temperature sensors correspond to the above-mentioned battery cell temperature sensor 40, the BMS temperature sensor 50, and the battery pack temperature sensor 60.

[0083] According to the present invention described above, overheating diagnosis or overheating diagnosis cause determination of each battery pack can be well understood by those skilled in the art, that is, the overheating diagnosis method is performed by installing a series of processor execution algorithms, which perform operations S10 to S40 in the BMS20 or the upper controller 210 of each battery pack.

[0084] As described above, in the battery pack and the method for diagnosing overheat of the battery pack according to the present invention, when overheating diagnosis is performed for stable operation of the battery, it can be distinguished whether the overheating is diagnosed due to overheating of the battery cells constituting the battery pack or the BMS itself, or whether the overheating is diagnosed due to environmental factors outside the battery pack, so as to achieve more accurate battery operation.

[0085] In the present invention, reference numerals and names of each component used are as follows.

[0086] 100 battery pack 200 system for diagnosing overheating of a battery pack

[0087] 10 battery pack 20BMS

[0088] 30 battery pack housing 31 temperature measurement hole

[0089] 32 Temperature transmission pin 40 Battery cell temperature sensor

[0090] 50BMS temperature sensor 60Battery pack temperature sensor

[0091] 70 Sensor mounted FPCB 71 Temperature sensor connection wire

[0092] 72 heat dissipation film 73 sensor installation part

[0093] 210 Upper controller

Claims

1. A battery pack, the battery pack being configured to perform overheat diagnosis of the battery pack, the battery pack comprising: one or more battery cells; a battery management system (BMS) configured to diagnose overheating of the battery pack according to an increase in an internal temperature of the battery pack or an increase in an external temperature of the battery pack, and determine whether a cause of the overheating diagnosis is due to an increase in the internal temperature of the battery pack or an increase in the external temperature; a battery pack housing configured to accommodate the battery cells and the BMS; one or more cell temperature sensors disposed adjacent the battery cells and configured to provide measurements for determining an increase in an internal temperature of the battery pack; as well as One or more battery pack temperature sensors are attached to an interior or exterior surface of the battery pack housing and are configured to provide measurements for determining an increase in an exterior temperature of the battery pack.

2. The battery pack according to claim 1, wherein: The BMS is configured to receive measurement values ​​from the cell temperature sensor at a predetermined period to determine an increase in an internal temperature of the battery pack, and to receive measurement values ​​from the battery pack temperature sensor at a predetermined period to determine an increase in an external temperature of the battery pack.

3. The battery pack according to claim 2, wherein: The BMS is configured to receive measurement values ​​from the battery cell temperature sensor and the battery pack temperature sensor to calculate a battery pack internal temperature and a battery pack external temperature according to the measurement values, and perform the overheat diagnosis of the battery pack based on the battery pack internal temperature value and the battery pack external temperature value, If the external temperature value of the battery pack increases earlier than the internal temperature value of the battery pack so that the overheat is diagnosed, it is determined that the cause of the overheat diagnosis is caused by an external factor of the battery pack.

4. The battery pack according to claim 3, further comprising a BMS temperature sensor disposed adjacent to the BMS, in, The BMS is configured to receive measurement values ​​from the cell temperature sensor and the BMS temperature sensor at a predetermined period in order to determine an increase in an internal temperature of the battery pack.

5. The battery pack according to claim 1, wherein: The battery pack temperature sensor is mounted on the inner surface of the battery pack housing, and The battery pack case is provided with a temperature measurement hole at a position corresponding to a portion to which the battery pack temperature sensor is attached.

6. The battery pack according to claim 5, wherein: The battery pack case further includes a temperature transfer pin configured to transfer the external temperature of the battery pack to the battery pack temperature sensor attached to the inner surface of the battery pack case through the temperature measurement hole.

7. The battery pack according to claim 5, wherein: A heat dissipation film is attached to a top surface of the pack temperature sensor facing the inner surface of the pack case to block heat.

8. A system for diagnosing overheating of a battery pack, the system comprising: One or more batteries according to any one of claims 1 to 7; as well as An upper level controller is configured to receive measured values ​​of the internal temperature of the battery pack and the external temperature of the battery pack from the battery pack so as to perform the overheat diagnosis of the battery pack.

9. The system according to claim 8, wherein: When overheating of the battery pack is diagnosed, the superior controller is configured to determine that the overheating is caused by an external factor of the battery pack when the external temperature of the battery pack rises above a predetermined reference value earlier than the internal temperature of the battery pack.

10. A method for diagnosing overheating of a battery pack, the method comprising: a battery pack internal temperature measurement process, wherein the battery pack internal temperature measurement process measures the internal temperature of the battery pack during a predetermined period of time; a battery pack external temperature measurement process, wherein the battery pack external temperature measurement process measures the external temperature of the battery pack during a predetermined period of time; a battery pack overheating diagnosis process, wherein the battery pack overheating diagnosis process diagnoses whether the battery pack is overheated based on the internal temperature of the battery pack and the external temperature of the battery pack; as well as An overheat diagnosis cause determination process determines that the overheat diagnosis is misdiagnosed when an external temperature of the battery pack increases earlier than an internal temperature of the battery pack in the overheat diagnosis process.

11. The method according to claim 10, wherein: In the overheat diagnosis process, when the internal temperature of the battery pack is greater than a predetermined reference value, the overheat is diagnosed as overheat of the battery pack. In the overheat diagnosis cause determination process, when the external temperature of the battery pack increases earlier than the internal temperature of the battery pack, the overheat is diagnosed as the overheat being caused by the increase in the external temperature.

12. The method according to claim 10 or 11, wherein: The internal temperature of the battery pack is acquired from a battery cell contained in a battery pack case of the battery pack or a temperature sensor mounted on a BMS, and The battery pack external temperature is obtained from a temperature sensor attached to the battery pack case of the battery pack.

13. A method for diagnosing overheating of a battery system, the battery system comprising one or more battery packs and an upper level controller, the one or more battery packs being provided with a separate temperature sensor to measure each of an internal temperature and an external temperature of the battery pack, the upper level controller receiving the internal temperature and the external temperature of each battery pack from the battery packs, the method comprising: a battery pack temperature measurement process, in which each battery pack measures the internal temperature and the external temperature of each battery pack; a measurement value receiving process, in which the upper controller receives the measurement values ​​of the internal temperature and the external temperature of each battery pack; an overheat diagnosis process in which the superior controller performs overheat diagnosis of each battery pack based on the received internal temperature and external temperature measurement values ​​of each battery pack; as well as An overheat diagnosis cause determination process determines whether the overheat diagnosis is caused by an internal factor or an external factor of the battery pack.

14. The method according to claim 13, wherein: Each battery pack measures the internal temperature and the external temperature from different temperature sensors attached at different locations of the battery pack.

15. The method according to claim 14, wherein: The internal temperature is acquired from a battery cell accommodated inside a battery pack case of the battery pack or a temperature sensor mounted on a BMS, and The external temperature is obtained from a temperature sensor attached to an outer surface or an inner surface of the battery pack case of the battery pack.

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