JP2019129003A - Battery abnormality detection system - Google Patents

Abstract

To provide a battery abnormality detection system, capable of detecting a battery abnormality during parking.SOLUTION: A control unit 35 includes: a selection section 39 which selects one assumed adaptation coefficient α1 among a plurality of assumed adaptation coefficients α1 stored in a storage section 37, on the basis of temperature Tx0 measured by a first temperature detection device 31 and outside air temperature Ty0 measured by a second temperature detection device 32; a calculation section 41 which calculates an actually measured adaptation coefficient α2, on the basis of the temperature Tx0 and temperature Tx1 measured by the first temperature detection device 31 and outer air temperature Ty1 measured by the second temperature detection device 32; and a determination section 43 which determines that a battery is abnormal when the assumed adaptation coefficient α1 selected by the selection section 39 is more than the actually measured adaptation coefficient α2, and determines that a battery is normal when the assumed adaptation coefficient α1 is equal to or less than the actually measured adaptation coefficient α2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a battery abnormality detection system.

  A battery such as a lithium ion secondary battery is generally used as a battery stack having a plurality of batteries or a battery pack in which a plurality of the battery stacks are combined. Here, when a variation in temperature occurs in each battery in the same stack, a variation in battery performance may occur between the batteries. When the battery performance varies, the possibility of overcharging in each battery increases. Here, as a technique for detecting a temperature change of a battery, for example, Patent Document 1 discloses a technique using cooling air flowing toward the battery during high load traveling. Further, Patent Literature 2 and Patent Literature 3 are listed as control technologies based on the temperature of the battery.

JP, 2015-129677, A JP, 2016-167420, A JP, 2012-029491, A

  By the way, with the technique described in Patent Document 1, the cooling air flows only during high-load traveling, and does not flow during normal traveling. Further, even during parking, which is the most frequently used form in the market, the cooling air does not flow and the change in battery temperature cannot be detected. That is, it is not possible to detect a battery abnormality while parking.

  This invention is made in view of this point, The objective is to provide the battery abnormality detection system which can detect abnormality of a battery in parking.

  The battery abnormality detection system according to the present invention is mounted on a vehicle including a vehicle driving battery. The battery abnormality detection system is a first temperature detection device that measures a temperature Tx0 of the vehicle drive battery at the end of travel and a temperature Tx1 of the vehicle drive battery when a predetermined time has elapsed from the end of travel; The control apparatus is provided with a second temperature detection device that measures the outside air temperature Ty0 of the vehicle at the end of traveling and the outside air temperature Ty1 of the vehicle when the predetermined time has elapsed from the end of traveling. The control device is associated with the outside temperature Ty2 of the vehicle at the end of travel, and the temperature Tx2 of the battery for driving the vehicle at the end of travel and the outside temperature of the vehicle when the predetermined time has elapsed from the end of travel A plurality of assumed fitness coefficients α1 that are ratios {Tx3 / (Tx2−Ty3)} of the temperature Tx3 of the vehicle driving battery when the predetermined time has elapsed from the end of traveling with respect to the difference from Ty3 (Tx2−Ty3). And a plurality of storage units stored in the storage unit based on the storage unit storing the temperature, the temperature Tx0 measured by the first temperature detection device, and the outside air temperature Ty0 measured by the second temperature detection device. A selection unit for selecting one of the assumed adaptation coefficients α1 from the assumed adaptation coefficient α1, the temperature Tx0 and the temperature Tx1 measured by the first temperature detection device, and Based on the outside air temperature Ty1 measured by the temperature detecting device, the actual measurement is a ratio {Tx1 / (Tx0−Ty1)} of the temperature Tx1 to the difference (Tx0−Ty1) between the temperature Tx0 and the outside air temperature Ty1. A calculating unit that calculates the adaptation coefficient α2, and the estimated adaptation coefficient α1 selected by the selection unit are determined to be abnormal if they are larger than the measured adaptation coefficient α2, and the estimated adaptation coefficient α1 is the measured adaptation coefficient α2 or less And a determination unit that determines that the condition is normal.

  According to the battery abnormality detection system according to the present invention, it is possible to calculate the estimated conformity which is calculated based on the temperature of the battery and the outside air temperature of the vehicle when the predetermined time has elapsed from the time of the end of traveling at normal time By comparing the coefficient α1 with the actually measured end of travel and the battery temperature when a predetermined time has elapsed from the end of travel and the actually measured adaptation coefficient α2 calculated based on the outside air temperature of the vehicle, Abnormality of the vehicle drive battery can be determined. That is, the determination unit determines as abnormal if the assumed adaptation coefficient α1 is larger than the actual adaptation coefficient α2, and determines that it is normal if the expected adaptation coefficient α1 is equal to or less than the actual adaptation coefficient α2. As described above, even when the vehicle is parked, it is possible to accurately detect whether or not an abnormality occurs in the vehicle drive battery. Moreover, since the presence or absence of abnormality of a vehicle drive battery can be detected in the state which is not using the vehicle drive battery, it is excellent by safety | security.

FIG. 2 is a top view schematically showing a battery abnormality detection system mounted on a vehicle. It is a flowchart which shows the procedure which confirms the state of the vehicle drive battery after parking. It is a graph which shows the temperature change after the parking of the battery for a vehicle drive.

  Hereinafter, preferred embodiments of the present invention will be described. Matters necessary for the implementation of the present invention other than matters specifically mentioned in the present specification can be grasped as design matters of those skilled in the art based on the prior art in this field. The present invention can be implemented based on the contents disclosed in the present specification and common technical knowledge in the field. In addition, each drawing is drawn typically and does not necessarily reflect a real thing. Each drawing shows only an example, and each drawing does not limit the present invention unless otherwise specified. In addition, symbols F, Rr, L, and R in the drawings mean front, rear, left, and right, respectively. However, these are directions for convenience of explanation, and do not limit the installation mode of the battery abnormality detection system.

  As shown in FIG. 1, the vehicle 10 includes a battery pack 20 and a battery abnormality detection system 30. In the present embodiment, the battery pack 20 is disposed below the rear seat of the vehicle 10 and is fixed to the floor panel. However, the battery pack 20 may be disposed other than the lower side of the rear seat.

  The battery pack 20 includes a battery stack 22 and a case 23. The battery stack 22 includes four vehicle driving batteries 21. The four vehicle drive batteries 21 each have a rectangular outer shape, and are arranged in a line in the left-right direction of FIG. 1 so that a pair of flat surfaces face each other. The four vehicle drive batteries 21 are electrically connected to each other in series by bus bars. The four vehicle drive batteries 21 are integrally held by a restraining band or the like. However, the shape, number and arrangement of the vehicle driving battery 21 may be changed as appropriate. The vehicle drive battery 21 is typically a chargeable / dischargeable secondary battery, for example, a lithium ion secondary battery. The vehicle drive battery 21 typically includes a positive electrode, a negative electrode, an electrolytic solution, and a single battery case that houses them. The electrolytic solution includes, for example, a nonaqueous solvent such as carbonates and a supporting salt such as a lithium salt. In addition, about the structure of a cell, it may be the same as that of the past, and is not specifically limited.

  The case 23 is a housing that accommodates the battery stack 22. The material of the case 23 is, for example, metal or resin. The shape and size of the case 23 may be changed as appropriate depending on, for example, the size and the number of the battery stacks 22.

  As shown in FIG. 1, the battery abnormality detection system 30 includes a first temperature detection device 31, a second temperature detection device 32, and a control device 35.

  The first temperature detection device 31 is a device that measures the temperature of the vehicle drive battery 21. As the 1st temperature detection apparatus 31, a thermocouple is mentioned, for example. The first temperature detection device 31 is provided in each vehicle driving battery 21. The 1st temperature detection apparatus 31 is attached to the cell case of the vehicle drive battery 21, for example. The first temperature detection device 31 is electrically connected to the control device 35. The temperature information measured by the first temperature detection device 31 is transmitted to the control device 35.

  The first temperature detection device 31 measures the temperature Tx0 of the vehicle drive battery 21 at the end of travel. The first temperature detection device 31 measures the temperature Tx1 of the vehicle drive battery 21 when a predetermined time t has elapsed since the end of traveling (that is, when a predetermined time t has elapsed after parking). The predetermined time t can be arbitrarily set, for example, 10 minutes, 30 minutes, or 1 hour.

  The second temperature detection device 32 is a device that measures the outside air temperature of the vehicle 10. The second temperature detection device 32 may, for example, be a thermistor. The second temperature detection device 32 is provided, for example, on the back side of the front bumper of the vehicle 10. The second temperature detection device 32 is electrically connected to the control device 35. The temperature information measured by the second temperature detection device 32 is transmitted to the control device 35.

  The second temperature detection device 32 measures the outside air temperature Ty0 of the vehicle 10 at the end of traveling. The second temperature detection device 32 measures the outside air temperature Ty1 of the vehicle when a predetermined time t has elapsed since the end of traveling (that is, when a predetermined time t has elapsed after parking).

  The control device 35 includes a central processing unit (CPU) that executes control program instructions, a ROM that stores a program to be executed by the CPU, a RAM used as a working area to expand the program, and the above-described programs and various data. And a storage device such as a memory for storing the The control device 35 includes a storage unit 37, a selection unit 39, a calculation unit 41, a determination unit 43, and a notification unit 45. These units are realized by programs. This program can be downloaded through the Internet. Each of these units may be realized by a processor and / or a circuit. The specific control of each unit described above will be described later.

  The storage unit 37 stores a plurality of assumed adaptation coefficients α1. The assumed compatibility coefficient α1 is at the end of traveling with respect to the difference (Tx2-Ty3) between the temperature Tx2 of the battery 21 for driving the vehicle at the end of traveling and the outside temperature Ty3 of the vehicle 10 when a predetermined time t has elapsed from the end of traveling. The ratio {Tx3 / (Tx2-Ty3)} of the temperature Tx3 of the vehicle drive battery 21 when the predetermined time t has elapsed from the above. The assumed fitness coefficient α1 is associated with the outside temperature Ty2 of the vehicle at the end of traveling. That is, if the outside temperature Ty2 and the temperature Tx2 are determined, the assumed adaptation coefficient α1 is uniquely determined. The assumed fitness coefficient α1 is an assumed value obtained by a preliminary experiment.

  The selection unit 39 sets the plurality of assumed compatibility coefficients α1 stored in the storage unit 37 based on the temperature Tx0 measured by the first temperature detection device 31 and the outside air temperature Ty0 measured by the second temperature detection device 32. And select one assumed adaptation coefficient α1 from. That is, the selection unit 39 uniquely selects the assumed adaptation coefficient α1 by replacing the temperature Tx0 with the temperature Tx2 and replacing the outside air temperature Ty0 with the outside air temperature Ty2.

  Based on the temperature Tx0 and temperature Tx1 measured by the first temperature detection device 31 and the outside air temperature Ty1 measured by the second temperature detection device 32, the calculation unit 41 calculates the difference between the temperature Tx0 and the outside air temperature Ty1 ( A measured adaptation coefficient α2 which is a ratio {Tx1 / (Tx0−Ty1)} of the temperature Tx1 to Tx0−Ty1) is calculated. The actually measured adaptation coefficient α2 is a measured value calculated based on the actually measured temperature and the outside air temperature.

  The determination unit 43 determines that the case is abnormal when the assumed compatibility coefficient α1 selected by the selection unit 39 is larger than the actual measurement compatibility coefficient α2 calculated by the calculation unit 41. If the assumed compatibility coefficient α1 selected by the selection unit 39 is less than or equal to the measured compatibility coefficient α2 calculated by the calculation unit 41, the determination unit 43 determines that the condition is normal.

  The notification unit 45 notifies the user of the abnormality of the vehicle drive battery 21. Note that the notification method is not particularly limited, and examples thereof include visual display and notification by voice. In the present embodiment, the operator is visually notified through a display panel (not shown) provided in the vehicle 10.

  Next, a method for confirming the state of the vehicle drive battery 21 after parking will be described. FIG. 2 is a flowchart according to one embodiment. At the time of shipment of the vehicle 10, the assumed fitness coefficient α <b> 1 is stored in the storage unit 37. When the vehicle 10 is parked, charging / discharging of the vehicle drive battery 21 is not performed.

  First, when traveling of the vehicle 10 ends (that is, when the vehicle 10 is parked), in step S10, the first temperature detection device 31 measures the temperature Tx0 of the vehicle drive battery 21 at the end of traveling. Further, the second temperature detection device 32 measures the outside air temperature Ty0 of the vehicle 10 at the end of traveling.

  Next, when the predetermined time t has elapsed, in step S20, the first temperature detection device 31 measures the temperature Tx1 of the vehicle drive battery 21 when the predetermined time t has elapsed from the end of traveling. Further, the second temperature detection device 32 measures the outside air temperature Ty1 of the vehicle 10 when a predetermined time t has elapsed from the end of traveling.

  In step S30, the selection unit 39 selects one assumed adaptation coefficient α1 from the plurality of assumed adaptation coefficients α1 stored in the storage unit 37 based on the temperature Tx0 and the outside air temperature Ty0 measured in step S10.

  In step S40, the calculation unit 41 calculates the measured adaptation coefficient α2 based on the temperature Tx0 measured in step S10 and the temperature Tx1 and the outside air temperature Ty1 measured in step S20.

  In step S50, the determination unit 43 determines whether the assumed adaptation coefficient α1 selected in step S30 is larger than the actual measurement adaptation coefficient α2. If it is determined that the assumed fitness coefficient α1 is greater than the actual fitness coefficient α2, the process proceeds to step S60. On the other hand, when it is determined that the assumed compatibility coefficient α1 is equal to or less than the actual measurement adaptation coefficient α2, the process is ended because the vehicle drive battery 21 is in a normal state.

  In step S60, the notification unit 45 notifies the user of the abnormality of the vehicle drive battery 21 and ends the process.

  FIG. 3 is a graph showing a temperature change for one hour after parking of the vehicle drive battery 21. The solid line in FIG. 3 indicates the temperature change when the assumed adaptation coefficient α1 is equal to the actual adaptation coefficient α2 (normal state). The broken line in FIG. 3 indicates a temperature change when the assumed adaptation coefficient α1 is larger than the actual adaptation coefficient α2 (abnormal state). As shown in FIG. 3, when the assumed adaptation coefficient α1 is equal to the actual measurement adaptation coefficient α2, the temperature of the vehicle drive battery 21 is sufficiently lowered. On the other hand, when the assumed compatibility coefficient α1 is larger than the actual measurement adaptation coefficient α2, the temperature of the vehicle drive battery 21 is not sufficiently lowered. As a result, it can be confirmed that, for example, dust is deposited on the vehicle drive battery 21 and the heat can not be sufficiently dissipated.

  As described above, according to the battery abnormality detection system 30 according to the present embodiment, the abnormality of the vehicle drive battery 21 can be determined by comparing the assumed adaptation coefficient α1 with the actual measurement adaptation coefficient α2. That is, the determination unit 43 determines an abnormality if the assumed adaptation coefficient α1 is larger than the actual measurement adaptation coefficient α2, and determines normal if the assumed adaptation coefficient α1 is less than or equal to the actual measurement adaptation coefficient α2. As described above, even if the vehicle 10 is parked, it can be accurately detected whether or not an abnormality occurs in the vehicle drive battery 21. In addition, when the vehicle 10 is parked, charging and discharging of the vehicle drive battery 21 is not performed, and the presence or absence of abnormality of the vehicle drive battery 21 can be detected in a state where the vehicle drive battery 21 is not used. , Better by safety.

  As mentioned above, although variously demonstrated about the battery abnormality detection system proposed here, unless otherwise mentioned, embodiment and the example which were mentioned here do not limit this invention.

  For example, although the process of step S30 is performed after step S20 in the flowchart described above, step S30 may be processed before step S20.

DESCRIPTION OF SYMBOLS 10 Vehicle 21 Battery 30 for vehicle drive Battery abnormality detection system 31 1st temperature detection apparatus 32 2nd temperature detection apparatus 35 Control apparatus 37 Memory | storage part 39 Selection part 41 Calculation part 43 Determination part

Claims (1)

A battery abnormality detection system mounted on a vehicle including a vehicle driving battery,
A first temperature detection device for measuring a temperature Tx0 of the vehicle drive battery at the end of travel and a temperature Tx1 of the vehicle drive battery when a predetermined time has elapsed from the end of travel;
A second temperature detection device for measuring the outside air temperature Ty0 of the vehicle at the end of traveling and the outside air temperature Ty1 of the vehicle when the predetermined time has elapsed from the end of traveling;
And a controller.
The controller is
A difference between the temperature Tx2 of the vehicle driving battery at the end of traveling and the outside temperature Ty3 of the vehicle when the predetermined time has elapsed from the end of traveling, which is related to the outside temperature Ty2 of the vehicle at the end of traveling ( A storage unit that stores a plurality of assumed fitness coefficients α1 that is a ratio {Tx3 / (Tx2−Ty3)} of the temperature Tx3 of the vehicle driving battery when the predetermined time has elapsed since the end of traveling with respect to Tx2−Ty3) When,
Based on the temperature Tx0 measured by the first temperature detection device and the outside air temperature Ty0 measured by the second temperature detection device, a plurality of the assumed fitness coefficients α1 to 1 stored in the storage unit. A selection unit for selecting the two assumed fitness coefficients α1,
Based on the temperature Tx0 and the temperature Tx1 measured by the first temperature detection device and the outside air temperature Ty1 measured by the second temperature detection device, a difference between the temperature Tx0 and the outside air temperature Ty1 ( A calculation unit that calculates a measured adaptation coefficient α2 that is a ratio {Tx1 / (Tx0−Ty1)} of the temperature Tx1 to Tx0−Ty1);
A determination unit that determines that an abnormality occurs when the assumed adaptation coefficient α1 selected by the selection unit is larger than the actual measurement adaptation coefficient α2, and determines that the assumption is normal when the assumed adaptation coefficient α1 is less than or equal to the actual measurement adaptation coefficient α2. And a battery abnormality detection system.

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