Battery Management Device

Abstract

To appropriately detect abnormality of a battery cell.SOLUTION: A battery management device includes: a battery module having a plurality of battery cells; a cooling plate for cooling the battery module; a first optical fiber arranged between the battery module and the cooling plate; a heat insulating member arranged between the cooling plate and the first optical fiber; and a temperature detection device for detecting the temperature of the plurality of battery cells based on scattered light generated when light enters the first optical fiber.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a battery management device.

Background Art

[0002] For example, Patent Document 1 discloses a technique for detecting the temperatures of a plurality of single cells based on Raman scattered light generated when light is incident on an optical fiber extending along the side surfaces of the plurality of single cells. In the technique of Patent Document 1, when the temperature of a single cell is relatively higher than the temperatures of other single cells, it is determined that the single cell is faulty.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the technique of Patent Document 1, the optical fiber on the side surface of the single cell located on the outer periphery among the plurality of single cells (battery cells) arranged together is liable to be damaged. If the optical fiber is damaged, it may become impossible to appropriately detect the temperature of the single cell. Further, in the technique of Patent Document 1, the optical fiber located between the plurality of single cells is affected by the temperatures of the respective single cells sandwiching the optical fiber. Then, it becomes unclear which of the plurality of single cells sandwiching the optical fiber has an abnormality.

[0005] Therefore, an object of the present invention is to provide a battery management device capable of appropriately detecting an abnormality in a battery cell.

Means for Solving the Problems

[0006] In order to solve the above problems, a battery management device according to an embodiment of the present invention is A battery module having multiple battery cells, A cooling plate for cooling the aforementioned battery module, A first optical fiber is disposed between the battery module and the cooling plate, A heat insulating member is disposed between the cooling plate and the first optical fiber, A temperature detection device that detects the temperature of the plurality of battery cells based on scattered light generated when light is incident on the first optical fiber, It is equipped with. [Effects of the Invention]

[0007] According to the present invention, it becomes possible to appropriately detect abnormalities in battery cells. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic diagram showing the configuration of the battery management device 1 according to this embodiment. [Figure 2] Figure 2 is a cross-sectional view of the cooling plate and battery module in the left-right direction of Figure 1. [Figure 3] Figure 3 is a cross-sectional view of the cooling plate and battery module in the vertical direction of Figure 1. [Figure 4] Figure 4 illustrates an example of the operation of the battery management unit. [Figure 5] Figure 5 illustrates another example of the operation of the battery management unit. [Figure 6] Figure 6 is a flowchart illustrating the operation flow of the battery management unit. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described in detail below with reference to the attached drawings. The specific dimensions, materials, numerical values, etc., shown in these embodiments are merely examples to facilitate understanding of the invention and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to avoid redundant explanations, and elements not directly related to the present invention are omitted from the illustrations.

[0010] Figure 1 is a schematic diagram showing the configuration of the battery management device 1 according to this embodiment. The battery management device 1 is applied to, for example, a vehicle 2. The vehicle 2 is, for example, an electric vehicle equipped with a motor generator as a drive source. The vehicle 2 may also be a hybrid electric vehicle equipped with a motor generator and an engine as drive sources.

[0011] The battery management device 1 comprises a battery pack 10, a battery module 12, a battery cell 14, a cooling plate 16, a first optical fiber 18, a second optical fiber 20, a temperature detection device 22, a heat insulating member 24, a control device 26, and an notification device 28.

[0012] The battery pack 10 is formed in a hollow box shape and is mounted on the vehicle 2. The battery pack 10 houses multiple battery modules 12. Figure 1 shows an example in which 10 battery modules 12 are housed inside the battery pack 10. Note that the number of battery modules 12 inside the battery pack 10 is not limited to the number shown as an example; it may be one or any number of modules.

[0013] In the example shown in Figure 1, when the battery pack 10 is viewed from above, the battery modules 12 are arranged in a 5x2 grid. Note that the arrangement of the battery modules 12 is not limited to this example; any arrangement that allows the battery modules 12 to be properly housed in the battery pack 10 is acceptable. For the sake of explanation, the battery modules 12 in the left column of Figure 1 may be referred to as the first column battery modules, and the battery modules 12 in the right column of Figure 1 may be referred to as the second column battery modules.

[0014] The battery module 12 has a plurality of battery cells 14. The battery cells 14 are rechargeable secondary batteries such as, for example, lithium-ion batteries. In FIG. 1, an example in which one battery module 12 has five battery cells 14 is shown. Note that the number of battery cells 14 included in one battery module 12 is not limited to the illustrated number and may be any plurality.

[0015] The plurality of battery cells 14 in one battery module 12 are electrically connected in series. That is, the plurality of battery cells 14 connected in series constitute a battery pack. Note that the battery module 12 may include a sensor that detects the voltage and current of the battery pack.

[0016] The battery cells 14 are formed, for example, in a flat plate shape and arranged so as to be stacked in the horizontal direction. In the example of FIG. 1, when the battery pack 10 is viewed from above the battery pack 10, the battery cells 14 are arranged so as to be stacked in the column direction.

[0017] The cooling plate 16 is formed in a flat plate shape and is located below the battery module 12. A plurality of battery modules 12 are in contact with a part of the cooling plate 16. Inside the cooling plate 16, a heat medium flow path 30 through which a heat medium flows is formed. The heat medium is a refrigerant such as, for example, water. The heat medium flow path 30 is formed so that the heat medium flows below the battery module 12.

[0018] For example, the heat medium flow path 30 is formed for each column of the battery modules 12 and extends across all of the battery modules 12 in one column. In the example of FIG. 1, a first column heat medium flow path 30a and a second column heat medium flow path 30b are formed as the heat medium flow path 30. The first column heat medium flow path 30a is continuously formed across the uppermost battery module 12 to the lowermost battery module 12 in the first column battery modules in FIG. 1. The second column heat medium flow path 30b is continuously formed across the uppermost battery module 12 to the lowermost battery module 12 in the second column battery modules in FIG. 1. The width in the left-right direction of the first column heat medium flow path 30a is not less than the width in the left-right direction of the first column battery modules. The width in the left-right direction of the second column heat medium flow path 30b is not less than the width in the left-right direction of the second column battery modules. The first column heat medium flow path 30a and the second column heat medium flow path 30b are connected on the side of the uppermost battery module 12 and are also connected on the side of the lowermost battery module 12.

[0019] A heat medium inlet 32 and a heat medium outlet 34 are formed in the cooling plate 16. The heat medium inlet 32 and the heat medium outlet 34 are each in communication with the heat medium flow path 30 inside the cooling plate 16. Further, the heat medium inlet 32 and the heat medium outlet 34 are each connected to a predetermined heat exchanger. The predetermined heat exchanger is, for example, a radiator or the like and cools the heat medium. The heat medium circulates between the predetermined heat exchanger and the cooling plate 16.

[0020] The heat medium is fed into the heat medium flow path 30 inside the cooling plate 16 through the heat medium inlet 32. The heat medium fed into the inside of the cooling plate 16 is split into the first column heat medium flow path 30a and the second column heat medium flow path 30b and flows through each of the first column heat medium flow path 30a and the second column heat medium flow path 30b. The heat medium that has flowed through each of the first column heat medium flow path 30a and the second column heat medium flow path 30b merges and is sent out of the cooling plate 16 through the heat medium outlet 34.

[0021] The first optical fiber 18 and the second optical fiber 20 are arranged along the surface of the cooling plate 16. The first optical fiber 18 and the second optical fiber 20 are arranged in a meandering manner along their longitudinal direction to cover multiple battery modules 12 and multiple battery cells 14.

[0022] For example, the first optical fiber 18 and the second optical fiber 20 extend from the top battery module 12 to the bottom battery module 12 along the right side of the second row of battery modules. The first optical fiber 18 and the second optical fiber 20 bend to the left side of the second row of battery modules at the bottom battery module 12 of the second row of battery modules, and extend along the left side of the second row of battery modules to the top battery module 12. The first optical fiber 18 and the second optical fiber 20 bend to the right side of the first row of battery modules from the second row of battery modules, and extend along the right side of the first row of battery modules from the top battery module 12 to the bottom battery module 12. The first optical fiber 18 and the second optical fiber 20 bend to the left side of the first row of battery modules at the bottom battery module 12 of the first row of battery modules, and extend along the left side of the first row of battery modules to the top battery module 12.

[0023] Figure 2 is a cross-sectional view of the cooling plate 16 and battery module 12 in the left-right direction of Figure 1. Figure 3 is a cross-sectional view of the cooling plate 16 and battery module 12 in the up-down direction of Figure 1.

[0024] As shown in Figures 2 and 3, a first groove 40 and a second groove 42 are formed in the cooling plate 16. The first groove 40 is formed on the surface of the cooling plate 16 facing the battery module 12 and is recessed from that surface. The first groove 40 is formed to be located below the battery cell 14.

[0025] The second groove 42 is formed on the back surface of the cooling plate 16, which is the surface opposite to the battery module 12 side, and is recessed compared to the back surface. The second groove 42 is formed to be located below the first groove 40. A heat transfer medium flow path 30 exists between the first groove 40 and the second groove 42. The first groove 40 is larger than the second groove 42.

[0026] The first groove 40 houses the heat insulating member 24 and the first optical fiber 18. The heat insulating member 24 and the first optical fiber 18 are housed such that the heat insulating member 24 is positioned relative to the cooling plate 16 side of the first optical fiber 18. That is, the first optical fiber 18 is positioned between the battery module 12 and the cooling plate 16, and the heat insulating member 24 is positioned between the cooling plate 16 and the first optical fiber 18. The first optical fiber 18 is positioned to be in contact with the battery cell 14 of the battery module 12.

[0027] Since the first optical fiber 18 is housed in the first groove 40, the first groove 40 extends along the longitudinal direction of the first optical fiber 18. In other words, the first groove 40 is formed along the path through which the first optical fiber 18 extends.

[0028] The heat insulating member 24 suppresses the transfer of heat from the heat transfer medium flowing through the heat transfer medium channel 30 of the cooling plate 16 to the first optical fiber 18. The heat insulating member 24 may be molded from any material that can appropriately suppress the transfer of heat from the heat transfer medium to the first optical fiber 18, such as urethane foam.

[0029] The second groove 42 houses the second optical fiber 20. That is, the second optical fiber 20 is positioned on the side of the cooling plate 16 opposite to the side where the first optical fiber 18 is positioned.

[0030] Since the second optical fiber 20 is housed in the second groove 42, the second groove 42 extends along the longitudinal direction of the second optical fiber 20. In other words, the second groove 42 is formed along the path through which the second optical fiber 20 extends.

[0031] As shown in Figure 1, the first optical fiber 18 and the second optical fiber 20 are connected to the temperature detection device 22. The temperature detection device 22 is configured to allow light to be incident on the first optical fiber 18 and the second optical fiber 20.

[0032] When light is incident on the first optical fiber 18 from its incident end, scattered light is generated at various points along the longitudinal direction of the first optical fiber 18, and some of the scattered light returns to the incident end of the first optical fiber 18. The temperature detection device 22 is configured to detect the backscattered light that returns to the incident end of the first optical fiber 18.

[0033] When light is incident on the second optical fiber 20 from its incident end, scattered light is generated at various points along the longitudinal direction of the second optical fiber 20, and some of the scattered light returns to the incident end of the second optical fiber 20. The temperature detection device 22 is configured to detect the backscattered light that returns to the incident end of the second optical fiber 20.

[0034] The temperature detection device 22 is configured to detect the temperature of multiple battery cells 14 based on scattered light generated when light is incident on the first optical fiber 18.

[0035] For example, the temperature detection device 22 can detect Brillouin scattered light, which is a type of backscattered light. The frequency of the Brillouin scattered light depends on the temperature at the longitudinal position of the first optical fiber 18 where the Brillouin scattered light was generated. For example, the frequency of the Brillouin scattered light generated at a high temperature will have a large frequency difference from the frequency of the incident light. Therefore, the temperature detection device 22 can determine the temperature at the location where the Brillouin scattered light was generated by converting the frequency difference between the frequency of the Brillouin scattered light and the frequency of the incident light of the first optical fiber 18 into a temperature.

[0036] Furthermore, the temperature detection device 22 can determine the location where the Brillouin scattered light was generated from the time it takes from the time when the incident light is incident on the first optical fiber 18 until the Brillouin scattered light is received.

[0037] Furthermore, as shown in Figure 1, the first optical fiber 18 extends along its longitudinal direction to cover multiple battery modules 12 and multiple battery cells 14. As a result, each of the multiple battery cells 14 is associated with a distance from the incident end of the first optical fiber 18. The distance from the incident end of the first optical fiber 18 is associated with the time from when incident light is incident on the first optical fiber 18 until the Brillouin scattered light is received. Also, since the first optical fiber 18 is positioned in contact with the battery cells 14, the temperature at each position along the longitudinal direction of the first optical fiber 18 depends on the temperature of the battery cells 14.

[0038] In other words, the temperature detection device 22 can identify the battery cell 14 whose temperature is to be detected from the time from when incident light is incident on the first optical fiber 18 until the Brillouin scattered light is received, and then detect the temperature of the identified battery cell 14 from the frequency of the Brillouin scattered light at that time.

[0039] The temperature detection device 22 can use the first optical fiber 18 to detect the temperature of each battery cell 14 housed in the battery pack 10. Therefore, the battery management device 1 can suppress the increase in cost for detecting the temperature of the battery cells 14 compared to a configuration in which multiple thermocouples are provided for each battery module 12 or battery cell 14.

[0040] Furthermore, as shown in Figure 2, the first optical fiber 18 is positioned between the battery module 12 and the cooling plate 16. Therefore, the battery management device 1 can prevent damage to the first optical fiber 18. Additionally, the battery management device 1 can suppress the need for additional space to accommodate components for detecting the temperature of the battery cells 14.

[0041] Furthermore, as shown in Figure 2, a heat insulating member 24 is placed between the first optical fiber 18 and the cooling plate 16. This makes it difficult for heat from the heat transfer medium inside the cooling plate 16 to be transferred to the first optical fiber 18, and makes it easier for the temperature of the battery cell 14 to be transferred to the first optical fiber 18. As a result, the battery management device 1 can accurately detect the temperature of the battery cell 14 using the first optical fiber 18 while suppressing the influence of heat from the heat transfer medium by the heat insulating member 24.

[0042] The temperature detection device 22 is configured to detect the temperature of the heat transfer medium flowing inside the cooling plate 16 based on scattered light generated when light is incident on the second optical fiber 20.

[0043] For example, the temperature detection device 22 can receive Brillouin scattered light that returns to the incident end of the second optical fiber 20. The temperature detection device 22 can determine the location where the Brillouin scattered light originated from the time between the incident light being incident on the second optical fiber 20 and the reception of the Brillouin scattered light.

[0044] Furthermore, as shown in Figure 2, the second optical fiber 20 is positioned in contact with the cooling plate 16. Therefore, the temperature of the second optical fiber 20 depends on the temperature of the heat transfer medium flowing through the heat transfer medium channel 30 inside the cooling plate 16.

[0045] Furthermore, the second optical fiber 20 is arranged parallel to the first optical fiber 18 with a cooling plate 16 in between. This allows the longitudinal distance of the second optical fiber 20 to be correlated with the longitudinal distance of the first optical fiber 18.

[0046] From these observations, the temperature detection device 22 can detect the temperature of the heat transfer medium inside the cooling plate 16 from the frequency of the Brillouin scattered light received by injecting incident light into the second optical fiber 20. Furthermore, the temperature detection device 22 can determine which of the multiple battery cells 14 corresponds to the temperature of the heat transfer medium at the detected location, based on the time elapsed from the time in which incident light is injected into the second optical fiber 20 until the Brillouin scattered light is received.

[0047] The temperature detection device 22 may associate the temperature of the battery cell 14 with the temperature of the heat transfer medium at the location corresponding to the battery cell 14 and store this information in a predetermined storage device for each battery cell 14.

[0048] In the battery management device 1, a second optical fiber 20 is provided for detecting the temperature of the heat transfer medium, in addition to the first optical fiber 18 for detecting the temperature of the battery cell 14, so that the temperature of the heat transfer medium can be detected with high accuracy.

[0049] Furthermore, the second optical fiber 20 extends along the first column of heat transfer fluid channels 30a and the second column of heat transfer fluid channels 30b. Therefore, the battery management device 1 can accurately detect the temperature distribution of the heat transfer fluid while suppressing the influence of heat transfer fluid movement.

[0050] This section described a configuration having both a first optical fiber 18 for detecting the temperature of the battery cell 14 and a second optical fiber 20 for detecting the temperature of the heat transfer medium. However, it is sufficient to have at least the first optical fiber 18 for detecting the temperature of the battery cell 14, and the second optical fiber 20 for detecting the temperature of the heat transfer medium may be omitted.

[0051] As shown in Figure 1, the control device 26 comprises one or more processors 50 and one or more memories 52 connected to the processors 50. The memories 52 include ROM, which stores programs, and RAM, which serves as a work area. The processors 50 also function as a battery management unit 60 in cooperation with the programs contained in the memories 52.

[0052] Figure 4 illustrates an example of the operation of the battery management unit 60. The battery management unit 60 acquires the temperature of the battery cell 14 and the temperature of the heat transfer medium detected by the temperature detection device 22. Here, the temperature of the heat transfer medium is assumed to be the temperature of the heat transfer medium associated with the temperature of the battery cell 14. The solid line T1 in Figure 4 shows an example of the time course of the temperature of the battery cell 14. The dashed line T2 in Figure 4 shows an example of the time course of the temperature of the heat transfer medium.

[0053] When the battery cell 14 is properly cooled by the heat transfer medium, the temperature of the battery cell 14 is maintained at approximately a constant level. Now, suppose that at time TM1, some abnormality occurs in the battery cell 14, and from time TM1 onward, the temperature of the battery cell 14 gradually rises. In this case, as the amount of heat that the heat transfer medium needs to cool increases, the temperature of the heat transfer medium gradually rises from time TM2 onward, following the rise in the temperature of the battery cell.

[0054] In Figure 4, "ΔT" represents the temperature of the battery cell 14, the temperature of the heat transfer medium, and the temperature difference. In the example in Figure 4, the temperature difference after time point TM2 does not increase significantly compared to the temperature difference before time point TM2. Furthermore, the temperature difference after time point TM2 remains roughly constant.

[0055] The battery management unit 60 performs a predetermined first notification control, which causes the notification device 28 to issue a predetermined first notification, when the temperature of the battery cell 14 exceeds a predetermined threshold. The notification device 28 may be, for example, a display device that displays a warning light, or a speaker that outputs a warning sound.

[0056] The predetermined threshold is set to be less than or equal to the cooling limit value, which is the limit of the cooling capacity of the cooling plate 16. In Figure 4, "Tc" shows an example of the cooling limit value, and "Tth" shows an example of the predetermined threshold value.

[0057] The first notification is, for example, a notification indicating that the temperature of the battery cell 14 is relatively high and that there is a suspicion of an abnormality in the battery cell 14. In other words, the battery management unit 60 notifies the passengers of the vehicle 2 via the notification device 28 that there is a suspicion of an abnormality in the battery cell 14.

[0058] This allows the battery management device 1 to alert the occupants of vehicle 2 to a suspected abnormality in the battery cell 14. As a result, the occupants of vehicle 2 can receive the first notification and consider inspecting and repairing vehicle 2.

[0059] Figure 5 illustrates another example of the operation of the battery management unit 60. The solid line T11 in Figure 5 shows an example of the time course of the temperature of the battery cell 14, and the dashed line T12 shows an example of the time course of the temperature of the heat transfer medium. Here, the temperature of the heat transfer medium is assumed to be the temperature of the heat transfer medium associated with the temperature of the battery cell 14.

[0060] For example, suppose that at time TM11, thermal runaway occurs in the battery cell 14 due to damage to the separator inside the battery cell 14. Thermal runaway means that the battery cell 14 continues to generate heat uncontrollably due to an internal short circuit or the like.

[0061] In the example shown in Figure 5, assume that the temperature of the battery cell 14 rises rapidly from time point TM11 onwards. In this case, the temperature of the heat transfer medium rises gradually from time point TM12 onwards, which is later than time point TM11, due to the effect of the temperature rise of the battery cell 14. Here, the heat transfer medium attempts to cool the battery cell 14, whose temperature is rising rapidly, but due to the influence of the heat capacity of the heat transfer medium, etc., it may not be able to sufficiently suppress the rapid temperature rise of the battery cell 14.

[0062] As a result, as shown in Figure 5, the time course of the heat transfer medium's temperature becomes slower than the time course of the battery cell 14's temperature, and the temperature difference "ΔT" between the battery cell 14's temperature and the heat transfer medium's temperature increases over time.

[0063] The battery management unit 60 then derives the temperature difference between the temperature of the battery cell 14 and the temperature of the heat transfer medium associated with the temperature of the battery cell 14. If the temperature difference is greater than or equal to a predetermined temperature difference, the battery management unit 60 executes a predetermined second notification control to cause the notification device 28 to issue a predetermined second notification.

[0064] The second notification is a specific notification indicating, for example, that the cooling of the battery module 12 by the cooling plate 16 is not working effectively. "Cooling is not working effectively" means that the temperature of the battery cells 14 is rising rapidly, and the cooling of the battery cells 14 by the heat transfer medium is not keeping up. It should also be noted that "cooling is not working effectively" may include cases where a malfunction occurs in the cooling of the heat transfer medium itself, resulting in the inability to cool the battery cells 14 by the heat transfer medium and a rapid rise in the temperature of the battery cells 14.

[0065] The predetermined temperature difference is set to an arbitrary value that allows for distinction between the mode in which the temperature difference "ΔT" increases over time, as shown in Figure 5, and the mode in which the temperature difference "ΔT" remains approximately constant over time, as shown in Figure 4.

[0066] The second notification contains information indicating a higher degree of urgency or importance than the first notification, such as a warning to evacuate immediately. Specifically, the battery management unit 60 notifies the occupants of the vehicle 2 via the notification device 28 that the cooling of the battery module 12 by the cooling plate 16 is not working effectively.

[0067] This allows the battery management device 1 to promptly notify the occupants of vehicle 2 of any abnormality of high urgency or importance. As a result, the occupants of vehicle 2 can receive the second notification and immediately evacuate from vehicle 2 to ensure their safety.

[0068] Figure 6 is a flowchart illustrating the operation flow of the battery management unit 60. The battery management unit 60 repeatedly executes the series of processes shown in Figure 6 each time a predetermined interrupt timing occurs at a predetermined interval.

[0069] When a predetermined interrupt timing arrives, the battery management unit 60 causes the temperature detection device 22 to detect the temperature of the battery cells 14 and the temperature of the heat transfer medium, and obtains the temperature of the battery cells 14 and the temperature of the heat transfer medium detected by the temperature detection device 22 (S10). At this time, the battery management unit 60 obtains the temperature of each battery cell 14 and the temperature of the corresponding heat transfer medium for all of the battery cells 14.

[0070] Next, the battery management unit 60 determines whether the acquired temperature of the battery cell 14 is above a predetermined threshold (S11). At this time, the battery management unit 60 performs the determination in step S11 for all of the battery cells 14.

[0071] If the temperature of any of the battery cells 14 is above a predetermined threshold (YES in S11), the battery management unit 60 causes the notification device 28 to issue a first notification (S12) and proceeds to the process in step S13. At this time, the battery management unit 60 may include in the content of the first notification content information the battery cell 14 whose temperature is above the predetermined threshold.

[0072] If the temperature of all battery cells 14 is below a predetermined threshold (NO in S11), the battery management unit 60 proceeds directly to step S13.

[0073] In step S13, the battery management unit 60 derives a temperature difference by subtracting the temperature of the heat transfer medium from the temperature of the battery cell 14 (S13). In this case, the battery management unit 60 derives the temperature difference from the temperature of the battery cell 14 and the temperature of the heat transfer medium corresponding to that battery cell 14. The battery management unit 60 also derives the temperature difference for all of the battery cells 14.

[0074] Next, the battery management unit 60 determines whether the temperature difference is greater than or equal to a predetermined temperature difference (S14). At this time, the battery management unit 60 performs the determination in step S14 for all of the multiple temperature differences for each battery cell 14.

[0075] If, in any temperature difference, the temperature difference is greater than or equal to a predetermined temperature difference (YES in S14), the battery management unit 60 causes the notification device 28 to execute a second notification (S15), and terminates the series of processes. At this time, the battery management unit 60 may include in the content of the second notification content information an identification of the battery cell 14 whose temperature difference is greater than or equal to the predetermined temperature difference.

[0076] If, in all of the multiple temperature differences, the temperature difference is less than a predetermined temperature difference (NO in S14), the battery management unit 60 terminates the series of processes.

[0077] This section described a method for executing a second notification in accordance with the temperature difference. However, if the second optical fiber 20 is omitted, the derivation of the temperature difference and the execution of the second notification in accordance with the temperature difference may be omitted.

[0078] Furthermore, in the flowchart described above, regardless of whether the determination in step S11 that the temperature of the battery cell 14 is above a predetermined threshold is YES or NO, the determination of whether the temperature difference in step S14 is above a predetermined temperature difference was made each time. However, the battery management unit 60 may perform the processing from step S13 onward only if the temperature of the battery cell 14 is above a predetermined threshold (YES in step S11), and may terminate the series of processes if the temperature of the battery cell 14 is below the predetermined threshold (NO in step S11). In other words, the determination of whether the temperature difference is above a predetermined temperature difference may be made only when the temperature of the battery cell 14 is above a predetermined threshold. This embodiment reduces the processing load compared to the embodiment in which the determination of whether the temperature difference is above a predetermined temperature difference is made each time.

[0079] As described above, in the battery management device 1 of this embodiment, a first optical fiber 18 is placed between the battery module 12 and the cooling plate 16, and a heat insulating member 24 is placed between the cooling plate 16 and the first optical fiber 18. The temperature of the multiple battery cells 14 is detected based on the scattered light generated when light is incident on the first optical fiber 18.

[0080] In the battery management device 1 of this embodiment, the first optical fiber 18 is located between the heat insulating member 24 and the battery module 12, thus preventing the first optical fiber 18 from being damaged. As a result, the battery management device 1 of this embodiment can prevent the temperature of the battery cell 14 from becoming undetectable. Furthermore, in the battery management device 1 of this embodiment, the heat insulating member 24 is located on the side of the first optical fiber 18 opposite to the battery module 12, thus blocking heat transfer from heat sources other than the battery cell 14. As a result, the battery management device 1 of this embodiment can identify the battery cell 14 and accurately detect its temperature.

[0081] Therefore, according to the battery management device 1 of this embodiment, it is possible to appropriately detect abnormalities in the battery cells 14.

[0082] Furthermore, in the battery management device 1 of this embodiment, if the temperature of the battery cell 14 detected using the first optical fiber 18 exceeds a predetermined threshold, a predetermined first notification control is executed.

[0083] As a result, the battery management device 1 of this embodiment makes it possible to appropriately recognize, for example, that there is a suspected abnormality in the battery cell 14, to the passengers of the vehicle 2.

[0084] Furthermore, in the battery management device 1 of this embodiment, the second optical fiber 20 is arranged on the side of the cooling plate 16 opposite to the side on which the first optical fiber 18 is arranged. The temperature of the heat transfer medium flowing inside the cooling plate 16 is detected based on the scattered light generated when light is incident on the second optical fiber 20.

[0085] As a result, the battery management device 1 of this embodiment can appropriately detect the temperature of the heat transfer medium that cools the battery module 12.

[0086] Furthermore, in the battery management device 1 of this embodiment, if the temperature difference between the temperature of the battery cell 14 detected using the first optical fiber 18 and the temperature of the heat transfer medium detected using the second optical fiber 20 is greater than or equal to a predetermined temperature difference, a predetermined second notification control is executed.

[0087] As a result, the battery management device 1 of this embodiment makes it possible to appropriately recognize to the occupants of the vehicle 2, for example, that the cooling of the battery module 12 by the cooling plate 16 is not working effectively.

[0088] Furthermore, in the battery management device 1 of this embodiment, the second notification control executes a notification indicating a higher degree of urgency or importance than the first notification control.

[0089] As a result, the battery management device 1 of this embodiment makes it possible to clearly distinguish and recognize abnormalities of relatively high urgency or importance to the occupants of the vehicle 2. Consequently, the battery management device 1 of this embodiment makes it possible to recognize the urgency or importance of abnormalities in the battery cells 14 to the occupants of the vehicle 2 at an early stage, thereby appropriately ensuring the safety of the occupants of the vehicle 2.

[0090] In the above embodiment, the temperature of the battery cell 14 and the temperature of the heat transfer medium were detected based on Brillouin scattered light. However, the temperature of the battery cell 14 and the temperature of the heat transfer medium are not limited to being detected based on Brillouin scattered light. For example, the temperature of the battery cell 14 and the temperature of the heat transfer medium may be detected based on Raman scattered light generated when light is incident on an optical fiber.

[0091] Embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to these embodiments. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention.

[0092] For example, in the above embodiment, the temperature detection device detected the temperature of the battery cell using a first optical fiber and the temperature of the heat transfer medium using a second optical fiber. However, the temperature detection device may also detect strain or pressure related to the battery cell using the first optical fiber, or detect strain or pressure related to the heat transfer medium using the second optical fiber. [Explanation of symbols]

[0093] 1 Battery management device 12 Battery Modules 14 battery cells 16 Cooling Plate 18. First Optical Fiber 20. Second optical fiber 22 Temperature detection device 24 Insulation material 26 Control device 50 processors 52 memory

Claims

1. A battery module having multiple battery cells, A cooling plate for cooling the aforementioned battery module, A first optical fiber is disposed between the battery module and the cooling plate, A heat insulating member is disposed between the cooling plate and the first optical fiber, A temperature detection device that detects the temperature of the plurality of battery cells based on scattered light generated when light is incident on the first optical fiber, A battery management device equipped with the following features.

2. Further equipped with a control device, The control device is One or more processors, One or more memories connected to the processor, It has, The aforementioned processor, When the temperature of the battery cell detected using the first optical fiber exceeds a predetermined threshold, a predetermined first notification control is executed. The battery management device according to claim 1, which performs a process including the following:

3. The cooling plate further comprises a second optical fiber disposed on the side opposite to the side on which the first optical fiber is disposed, The temperature detection device is The battery management device according to claim 1, wherein the temperature of a heat transfer medium flowing inside the cooling plate is detected based on scattered light generated in response to light being incident on the second optical fiber.

4. Further equipped with a control device, The control device is One or more processors, One or more memories connected to the processor, It has, The aforementioned processor, If the temperature difference between the temperature of the battery cell detected using the first optical fiber and the temperature of the heat transfer medium detected using the second optical fiber is greater than or equal to a predetermined temperature difference, a predetermined second notification control is executed. The battery management device according to claim 3, which performs a process including the following:

5. The aforementioned processor, When the temperature of the battery cell detected using the first optical fiber exceeds a predetermined threshold, a predetermined first notification control is executed. Execute the process that includes, The battery management device according to claim 4, wherein the second notification control executes a notification indicating a higher degree of urgency or importance than the first notification control.

Images