JP2009099473A - Abnormality detecting device for power storage device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a precision in detecting failures of a thermistor to detect the temperature of a power storage device. <P>SOLUTION: A voltage detection part 12 detects potential Vt from a reference potential of a block B. A voltage detection part 14 calculates a temperature of the block B based on the potential Vs from the reference potential of a thermistor 42 installed on the surface of the block B constituting the battery pack 20. An abnormality determination part 16 detects abnormality of liquid leakage of the block B based on at least any of the potential Vs of the thermistor and the potential Vt of the block B. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an abnormality detection technique in a system including a power storage device.

  When a power storage device such as a secondary battery or a capacitor is repeatedly charged or discharged for a long period of time, the deterioration gradually proceeds and the electrolyte may leak out from the inside of the case. If such a phenomenon is left unattended, there is a risk of a decrease in input / output of the power storage device or an electric leakage. Therefore, it is desirable to detect and treat liquid leakage of the power storage device at an early stage.

  Patent Document 1 discloses a technique for detecting a liquid leak based on the presence or absence of a current flowing through the liquid using the conductivity of the liquid leaking from the battery. Specifically, the leakage is detected by using a leakage breaker in a circuit for detecting the leakage. Alternatively, if the entire battery is covered with an outer box of a metal case, and if a liquid leak occurs and a part of the battery is short-circuited via the metal case and the electrolyte, the liquid leak is detected via a transistor provided outside the metal case. is doing.

  In addition, a control device that controls charging and discharging of a power storage device such as a secondary battery or a capacitor may use temperature information of the power storage device as a control parameter. The temperature of the power storage device is detected using, for example, a temperature resistance element such as a thermistor disposed on the surface of the power storage device as disclosed in Patent Document 2. Here, when the power storage device leaks as described above, a short circuit may occur between the temperature resistance element and the power storage device. In this case, the temperature resistance element may detect an abnormal temperature due to the influence of the short circuit. However, the cause of the temperature resistance element detecting an abnormal temperature may be a malfunction of the temperature resistance element itself in addition to the liquid leakage of the power storage device. Therefore, even if the temperature detected by the temperature resistance element is abnormal, it is not easy to specify the cause.

JP-A-5-326032 Japanese Patent Laid-Open No. 5-15078

  By the way, it is difficult to detect at the initial stage of a liquid leak by the method of detecting a liquid leak with the earth-leakage circuit breaker, transistor, etc. which were provided in the outer side of the battery main body like patent document 1. FIG. Further, in the case of an assembled battery in which a plurality of battery blocks are connected in series, it is difficult to specify in which block the liquid leakage has occurred.

  Furthermore, when the detection of the liquid leakage of the power storage device as shown in Patent Document 1 is performed independently of the detection of the malfunction of the temperature resistance element such as a thermistor that detects the temperature of the power storage device, There is a possibility that the means for detecting the malfunction may erroneously detect that the temperature resistance element is abnormal in spite of the liquid leakage of the power storage device.

  An object of the present invention is to detect liquid leakage from a power storage device at an initial stage.

  An abnormality detection device for a power storage device according to the present invention includes a temperature detection unit that detects a potential Vs from a reference potential of a temperature resistance element provided on a surface of the power storage device, and a potential Vt from the reference potential of the power storage device. A voltage detection unit for detecting, and an abnormality detection unit for detecting a liquid leakage abnormality of the power storage device based on at least one of the potential Vs of the temperature resistance element and the potential Vt of the power storage device. And

  In one aspect of the abnormality detection device according to the present invention, the abnormality detection unit is configured to compare the potential Vt from the reference potential of the power storage device with the potential Vs of the temperature resistance element. It is characterized by determining the presence or absence of liquid leakage.

  In one aspect of the abnormality detection device according to the present invention, the abnormality detection unit includes a potential Vt from the reference potential of the power storage device and a potential Vcc from the reference potential of a power source supplied to the temperature resistance element. On the basis of the comparison, the presence or absence of liquid leakage of the power storage device is determined.

  In one aspect of the abnormality detection device according to the present invention, the abnormality detection unit detects whether or not there is a liquid leak in the power storage device based on a comparison between the reference potential and the potential Vt from the reference potential of the power storage device. This determination is performed.

  In one aspect of the abnormality detection device according to the present invention, the power storage device is at least one battery block electrically connected in series, and the abnormality detection unit is a potential from the reference potential of the power storage device. Based on a comparison between a value obtained by multiplying Vt by a coefficient determined based on the number of battery blocks constituting the power storage device and the potential Vs of the temperature resistance element, the presence or absence of liquid leakage of the power storage device is determined. It is characterized by that.

  In one aspect of the abnormality detection device according to the present invention, the abnormality detection unit sets the number of battery blocks constituting the power storage device to M, an integer not less than 1 and not more than M, m to the coefficient, m / M, a predetermined value. When the threshold value of S is S and m satisfying | Vs−m / M × Vt | ≦ S exists, an abnormality is detected as a leakage of the battery block connected m-th from the reference potential side. And

  An abnormality detection device for a power storage device according to the present invention includes a temperature detection unit that calculates a temperature of the power storage device based on a potential Vs from a reference potential of a temperature resistance element provided on a surface of the power storage device, and the temperature resistance An abnormality detection unit that detects an abnormality as a malfunction of the temperature resistance element when the potential Vs of the element is not included in a predetermined potential range, and prior to the detection of the malfunction of the temperature resistance element, An abnormality detection unit that performs the determination of the presence or absence of liquid leakage and detects the malfunction of the temperature resistance element only when the liquid leakage of the power storage device is not detected.

  According to the present invention, it is possible to detect liquid leakage of the power storage device at an initial stage.

  The best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described by taking an assembled battery as an example of a power storage device.

  FIG. 1 is a block diagram showing the configuration of the abnormality detection apparatus according to this embodiment. The abnormality detection device is mounted on, for example, a hybrid electric vehicle, and detects the voltage and temperature of the assembled battery. In FIG. 1, an assembled battery 20 as a power storage device is configured by connecting n battery blocks B1 to Bn (hereinafter simply referred to as blocks B1 to Bn) in series. Of both terminals of the block Bn connected to the terminal, the terminal tn + 1 to which the block is not connected in the subsequent stage is grounded (G2). Each of the blocks B1 to Bn is configured by electrically connecting two battery modules in series, and each battery module is configured by electrically connecting six unit cells in series. . As each single battery, a nickel metal hydride battery, a lithium ion battery, or the like can be used. In addition, the number of blocks, battery modules, and single cells is not particularly limited. For example, the block may be configured by one single cell. The configuration of the assembled battery 20 is not limited to the above example.

  In FIG. 1, a battery electronic control unit (hereinafter referred to as a battery ECU) 10 is grounded (the same potential as the grounding point G and the grounding point G2), and the battery pack 20 is charged based on the voltage or temperature of the battery pack 20. Control the discharge.

  The battery ECU 10 includes a voltage detection unit 12, a temperature detection unit 14, and an abnormality detection unit 16. The voltage detection unit 12 is sequentially connected to the terminals t1 to tn + 1 of the blocks B1 to Bn via the MUX (multiplexer) 30, and receives the potentials Vt1 to Vtn + 1 from the ground point G2, which are reference potentials of the terminals of the blocks. get. The voltage detector 12 calculates the inter-terminal voltage Vb of each block by calculating the potential difference between both ends of each block. The voltage detection unit 12 may obtain the potentials Vt1 to Vtn + 1 by sequentially acquiring the inter-terminal voltages Vb of the blocks B1 to Bn via the MUX 30 and sequentially adding them.

  The temperature detection unit 14 acquires temperature information of each block B1 to Bn from the temperature sensor 40 provided in each block B1 to Bn via the MUX 32, and calculates the temperature of each block B1 to Bn based on each temperature information. To do.

  The temperature information of each block B1 to Bn can be measured by detecting the potential from the ground point of a temperature resistance element such as a thermistor or a platinum thermometer. In this embodiment, the case where a thermistor is used as the temperature resistance element will be described below. The temperature sensor 40 includes a thermistor 42 and a resistor 44. The thermistor 42 is disposed in contact with the surface of the unit cell constituting the block B in an electrically insulated state. One end of the thermistor 42 is connected to the power source Vcc via the resistor 44, and the other end of the thermistor 42 is grounded. (Grounding point G1 and the same potential as the grounding point G of the battery ECU 10). The temperature of the thermistor 42 arranged in this way changes so as to be approximately equal to the surface temperature of the single cells constituting the block B, and the electrical resistance of the thermistor 42 changes according to the surface temperature of the block B. Therefore, the potential Vs from the ground point G1 that is the reference potential at the connection point C between the thermistor 42 and the resistor 44 also changes according to the surface temperature of the block B.

  Therefore, the temperature detection unit 14 acquires the potential Vs of the thermistor 42 as temperature information, and calculates the temperature Tb of the block B based on the potential Vs. The temperature detection unit 14 calculates the temperature Tb based on the potential Vs with reference to a map showing the relationship between the potential Vs and the temperature Tb as shown in FIG. 2, for example. The map may be created based on the measurement results obtained by measuring a plurality of potentials Vs and temperatures Tb in advance based on experiments or the like.

  In the abnormality detection device configured as described above, in the present embodiment, the abnormality detection unit 16 determines the presence or absence of liquid leakage of the blocks constituting the assembled battery 20 prior to the determination of whether or not the thermistor 42 is defective.

  More specifically, the abnormality detection unit 16 performs the process shown in the flowchart shown in FIG. 3 and determines whether or not there is a malfunction of the thermistor 42 after determining whether or not there is a liquid leak in the block. As described above, the abnormality detection unit 16 improves the accuracy of detecting the thermistor failure by determining the presence or absence of the liquid leakage of the block constituting the assembled battery 20 prior to the determination of the presence or absence of the failure of the thermistor 42. be able to. That is, when the potential Vs of the thermistor 42 does not show a normal value due to liquid leakage from the block, the abnormality detection unit 16 is based on the fact that the potential Vs of the thermistor 42 does not show a normal value. It is possible to prevent erroneous detection as a malfunction.

  In order for the abnormality detection unit 16 to detect liquid leakage from the block, it is necessary that the electrolytic solution leaking from the block directly contacts the thermistor 42. Examples of the direct contact include a case where the insulating film covering the thermistor 42 deteriorates and comes into contact with the electrolytic solution, or a case where the electrolytic solution crawls up from a conductor portion connecting the thermistor 42 and a circuit such as the MUX 32. . In addition, a hole is intentionally formed partially in the insulating film of the thermistor 42, and temperature measurement is performed without any trouble in a normal state where there is no liquid leakage. When the liquid leaks, the electrolyte is directly contacted through the hole, A leak may be detected.

  3, the abnormality detection unit 16 acquires the potential Vs of the thermistor 42 from the temperature detection unit 14 (S100), and further acquires the potentials Vt1 to Vtn + 1 of each terminal of each block from the voltage detection unit 12 (S102). Next, the abnormality detection unit 16 first determines the presence or absence of liquid leakage from the block based on the acquired potential information (S104).

  Here, the determination of the leakage of the block is specifically performed as follows.

First, when one terminal of any block and the connection point C of the thermistor 42 are short-circuited, the potential Vs of the thermistor 42 and the potential Vt of the terminal of the short-circuited block are substantially equal. Therefore, the abnormality detection unit 16 determines that the block is leaking when there is a terminal having a potential Vt whose difference from the potential Vs is equal to or less than a predetermined threshold S. That is, the abnormality detection unit 16 determines that there is liquid leakage from the block when there is a terminal that satisfies the following expression (1).
| Vt−Vs | ≦ S (1)

When one end D of the resistor 44 on the power supply side and one terminal of any block are short-circuited, the potential Vt of the short-circuited terminal becomes substantially equal to the potential Vcc of the power supply. Therefore, the abnormality detection unit 16 determines that there is liquid leakage in the block when there is a terminal having a potential Vt whose difference from the potential Vcc is equal to or less than a predetermined threshold S. That is, the abnormality detection unit 16 determines that there is liquid leakage from the block when there is a terminal that satisfies the following equation (2).
| Vt−Vcc | ≦ S (2)

Further, when the ground point G1 of the thermistor 42 and one terminal of any block are short-circuited, the potential Vt of the short-circuited terminal becomes zero. Therefore, the abnormality detection unit 16 determines that there is liquid leakage from the block when there is a terminal having a potential Vt that is equal to or lower than the predetermined threshold S. That is, the abnormality detection unit 16 determines that there is liquid leakage from the block when there is a terminal that satisfies the following expression (3).
| Vt | ≦ S (3)

  As described above, the case where any of the terminals at both ends of the block is short-circuited due to liquid leakage has been described. However, short-circuiting due to liquid leakage is not necessarily the terminals at both ends of the block. That is, it is also conceivable that single cells other than the single cells connected to the both ends of the block leak and short-circuit with the connection point C of the thermistor 42. In such a case, the presence or absence of liquid leakage in the block B can be determined under the following conditions.

That is, for example, the block is configured by connecting six single cells in series, and the positive electrode side of the second single cell from the negative electrode side (that is, the ground potential side that is the reference potential), and 3 from the negative electrode side. When a short circuit with the connection point C of the thermistor 42 occurs at the connection point with the negative electrode side of the first unit cell, the potential Vs of the thermistor 42 becomes substantially equal to 2/6 of the potential Vt on the positive electrode side of the block. . Further, at the connection point between the positive electrode side of the fifth unit cell from the negative electrode side and the negative electrode side of the sixth unit cell (that is, the most positive electrode side) from the negative electrode side, a short circuit with the connection point C of the thermistor 42 occurs. When it occurs, the potential Vs of the thermistor 42 is approximately equal to 5/6 of the potential Vt on the positive side of the block. As described above, the abnormality detection unit 16 causes the block to leak when there is a terminal satisfying the following expression (4), where M is the number of cells constituting the block, and m is an integer of 1 or more and M or less. It can be determined that
| Vs−m / M × Vt | ≦ S (4)

  Moreover, it can be narrowed down which cell in the block has caused the liquid leak by determining the liquid leak of the block based on the conditional expression (4). In other words, when m ′ is an integer that satisfies Equation (4), the positive side of the unit cell connected m ′ from the negative side or the negative side of the unit cell connected m ′ + 1 from the negative side The thermistor leaks and a short circuit occurs. Therefore, in this case, there is a high possibility that the m′-th or m ′ + 1-th unit cell is leaking. Further, when the storage performance is lost due to liquid leakage and the inter-terminal voltage Vb ′ is approximately 0 V, the integer satisfying the equation (4) is m ′. In this case, there is a high possibility that the m ′ + 1-th unit cell from the negative electrode side leaks and the positive electrode side or the negative electrode side of the m ′ + 1-th unit cell from the negative electrode side is short-circuited with the thermistor due to liquid leakage.

  In the process of losing the storage battery performance, the battery whose storage performance has deteriorated due to liquid leakage is finally stored after the voltage Vb between the terminals decreases to near 0 V during discharging and the terminal voltage Vb ′ recovers during charging. It is known to lose performance. Therefore, by referring to the time transition in the relationship between the charge / discharge current value and the potential, it is possible to further narrow down which single cell in the block is causing the liquid leakage.

  As described above, the abnormality detection unit 16 first determines whether any one of the potentials Vt1 to Vtn + 1 of each terminal of each block satisfies any of the above-described conditional expressions, so that the block B The presence or absence of liquid leakage is determined. As a result, when the liquid leakage of the block B has occurred, the abnormality detection unit 16 notifies the liquid leakage of the block B to the outside as an abnormality (S108).

  On the other hand, as a result of the determination in step S104, when the liquid leakage of the block B has not occurred (the determination result in step S106 is negative “N”), the abnormality detection unit 16 determines whether or not the thermistor 42 is defective. . Specifically, the abnormality detection unit 16 determines whether or not the thermistor 42 is defective based on whether or not the potential Vs of the thermistor 42 is included in a predetermined potential range.

  Here, the temperature range of each block B assumed when the assembled battery 20 normally charges and discharges is, for example, −30 ° C. to 80 ° C. Therefore, the range of the thermistor potential Vs corresponding to this temperature range can be determined to be, for example, 0.7 V to 4.5 V from a reference map as shown in FIG. That is, if the potential Vs of the thermistor is not included in this potential range, the thermistor 42 may be defective. Therefore, the abnormality detection unit 16 determines whether or not the thermistor 42 is defective based on whether or not the potential Vs of the thermistor is included in a predetermined potential range (S110).

  As a result of the determination, if the thermistor potential Vs is not included in the predetermined potential range (the determination result of step S110 is negative “N”), the abnormality detection unit 16 indicates that the thermistor 42 is not functioning normally. Assuming that there is a possibility of a malfunction of the thermistor 42, the malfunction of the thermistor 42 is notified to the outside as an abnormality (S112).

  As described above, in the present embodiment, the abnormality detection unit 16 determines whether or not there is a liquid leak in the block B prior to determining whether or not the thermistor 42 is defective. Thereby, the abnormality detection unit 16 can prevent erroneous determination that the thermistor 42 is abnormal in the case of the liquid leakage of the block B. Therefore, it is possible to improve the accuracy of detecting a malfunction of the thermistor. Moreover, in this embodiment, since the leak of the block B is detected using the thermistor 42 disposed in contact with the block B, the leak of the block B can be detected in the initial stage. That is, the liquid leakage can be detected earlier than when the liquid leakage is detected by an earth leakage circuit breaker or a transistor provided outside the assembled battery.

  In the above embodiment, the threshold value S in each of the equations (1) to (3) used for determining the leakage of the block represents an allowable error in measurement. Accordingly, the threshold value S is determined by noise, that is, an external noise or thermal noise, an error that is randomly generated due to a stochastic variation caused by a circuit configuration such as the voltage calculation circuit 12 or the like. In addition, it is determined in consideration of how much the design of the system affects the result of the equation obtained from the measured value. For example, when the battery voltage to be measured fluctuates at a high frequency, the measurement voltage varies greatly depending on the measurement timing of the storage battery potential and the thermistor potential, so the threshold S must be determined in consideration of the fluctuation speed of the measurement voltage. is there.

  Under the condition that the battery voltage does not fluctuate, for example, when charging or discharging is not performed, the influence of the tolerance can be reduced by performing the measurement a plurality of times and obtaining an average value thereof. Although depending on a measurement circuit such as a quantization error of an A / D conversion circuit that converts an analog value into a digital value, when the power supply Vcc is 5 V and the resolution of the A / D conversion circuit is 10 bits, for example, the threshold S is 10 It is preferable that it is 0.05 V or less corresponding to about a bit.

On the other hand, when the battery voltage fluctuates due to charging or discharging, if the thermistor 42 and the block are short-circuited, the potential of the thermistor 42 also fluctuates, so the threshold value S is set to a large value, for example, 0.2V. Set. Then, each of the above formulas based on voltage values acquired in time series (
By performing the determinations according to 1) to (3) and performing a process of determining that the condition of the expression has been established when the number of consecutive establishments of the expressions (1) to (3) determined in advance is exceeded, It is possible to prevent misjudgment while allowing the time difference of the A / D conversion between the battery voltage and the voltage of the thermistor 42 and the influence of noise.

  Further, the threshold value S in the equation (4) used for determining the liquid leakage of the block is used when determining which of the m-th cell and the m + 1-th cell has a liquid leak. Therefore, if the threshold value S is equal to or higher than the voltage between the terminals of the unit cell, it cannot be distinguished whether the leaked unit cell is the mth unit cell or the m ± 1 unit cell. Therefore, the threshold value S is desirably a nominal voltage of the battery, or 1.2 V for the nickel metal hydride battery. The nominal voltage of the battery is a voltage given for each battery for convenience, and it is difficult to say that the usage pattern of the battery is necessarily considered. Therefore, it is effective to use the voltage at which a normal battery is used as the threshold value S in consideration of the battery usage. For example, a nickel metal hydride battery mounted on a hybrid electric vehicle is generally controlled at a voltage of 1.0 V to 1.4 V during operation, and a lithium ion secondary battery is operated at a voltage of 3.4 V to 4.0 V. Be controlled. Therefore, it is effective to use a voltage within a range assumed during operation as the threshold S.

  Further, in the above-described embodiment, the example in which the presence / absence of the leakage of the block B is determined prior to the determination of the presence / absence of the malfunction of the thermistor 42 has been described. However, after determining that the potential Vs of the thermistor 42 is not included in the predetermined potential range, the abnormality detection unit 16 determines whether or not there is a liquid leak in the block B, and determines that there is no liquid leak in the block B. An abnormality may be detected as a malfunction of the thermistor 42 only when it is detected. That is, even when the abnormality detection unit 16 does not determine whether or not there is a leakage of the block B prior to determining whether or not the thermistor 42 is defective, the abnormality detection unit 16 gives priority to the leakage of the block B over the failure of the thermistor 42. Can be detected.

  Furthermore, in the above-described embodiment, an example in which the potential of the terminal is measured in units of blocks and compared with the potential Vs of the thermistor 42 has been described. However, for example, the potential of the terminal may be measured for each battery module constituting the block or each single cell constituting the battery module, and compared with the potential Vs of the thermistor 42 to determine the presence or absence of liquid leakage. . Thus, by measuring the potential of the terminal in units of battery modules or single cells, it becomes easier to identify the single cell in which liquid leakage has occurred.

  In the above embodiment, the case where the reference potential is the ground point has been described as an example. However, the reference potential is not limited to the ground point, and for example, the most negative potential of each battery block may be used as the reference potential of each battery block.

  Hereinafter, a modified example of the present embodiment for determining the presence or absence of liquid leakage for each cell will be described with reference to FIG. 4 with the most negative potential of each battery block as the reference potential of each battery block.

  FIG. 4 shows a configuration block of an abnormality detection apparatus according to a modification. In the above embodiment, the reference potential is the ground potential of the assembled battery. However, in the modification, the reference potential is the most negative potential G1n of the battery block B20n. This potential is the same as the ground point G1 of the thermistor 42 and the ground point G of the battery ECU 10 in the above embodiment. Also, the voltage regulator 46n has the same potential as the grounding point.

  In FIG. 4, the assembled battery 200 is represented by blocks B201 to B20N (hereinafter referred to as a block B20n when it is not necessary to distinguish between them). Each functional block is referred to as an electrical series connection). Each block B20n is configured by electrically connecting four unit cells Bn1 to Bn4 in series. The assembled battery 200 is insulated from the abnormality detection unit 160.

  Each terminal of each unit cell Bn1 to Bn4 is connected to a multiplexer (MUX) 30n via potential detection lines Ln1 to Ln5. The MUX 30n is sequentially connected to both ends of each of the unit cells Bn1 to Bn4 via each potential detection line Ln, sequentially A / D-converts the inter-terminal voltages Vbn1 to Vbn4, and outputs them to the voltage detection unit 12n. The voltage detector 12n sequentially detects the inter-terminal voltages Vbn1 to Vbn4 of the single cells Bn1 to Bn4 via the MUX 30n. The voltage detection unit 12n obtains the potentials Vtn1 to Vtn4 by sequentially adding the inter-terminal voltages Vbn1 to Vbn4, and outputs them to the abnormality detection unit 160.

  Similar to the above embodiment, the thermistor 42n is disposed in contact with the block B20n in a state of being electrically insulated as the temperature sensor 40n. The thermistor 42n is supplied with the reference voltage Vccn from the battery block B20n via the voltage regulator 46n. The temperature detection unit 14n detects the temperature of the block B20n based on the potential Vsn from the reference potential G1n of the thermistor 42n. The temperature detection unit 14n outputs a signal obtained by A / D converting the potential Vsn to the abnormality detection unit 160.

  Each signal indicating the potential Vtn1 to Vtn4 of each single cell output from the voltage detection unit 12n and the signal indicating the potential Vsn of each thermistor output from the temperature detection unit 14n are sent to the abnormality detection unit 160 via the insulating unit 60. Entered.

  In FIG. 4, the current sensor 50 detects the charging / discharging current I of the assembled battery 200 and inputs it to the current detector 52. The current detection unit 52 performs A / D conversion on the input charge / discharge current I signal and outputs the signal to the abnormality detection unit 160. The current sensor 50 measures the charge / discharge current I of the assembled battery 200 using a Hall element while maintaining the electrical insulation between the body of the hybrid electric vehicle and the assembled battery 200, for example.

  In the abnormality detection device configured as described above, the abnormality detection unit 160 is similar to that in the above embodiment based on the potentials Vtn1 to Vtn4 from the voltage detection unit 12n and the potential Vsn from the temperature detection unit 14n. On the basis of the processing procedure shown in FIG. 4, the determination of the presence or absence of liquid leakage for each unit cell and the determination of the presence or absence of malfunction of the thermistor are performed. Note that the description of “block” in FIG. 3 should be read as “single cell” as appropriate. Moreover, what is necessary is just to perform determination of the presence or absence of the liquid leak of a cell based on Formula (1)-(4) similarly to said embodiment.

  As described above, according to this modification, it is possible to detect the presence or absence of liquid leakage for each unit cell constituting the assembled battery.

It is a figure which shows the structural block of the abnormality detection apparatus in this embodiment. It is a figure which shows an example of the map referred when a temperature detection part calculates the temperature of a battery based on the electric potential of a thermistor. It is a flowchart which shows the procedure in which the abnormality detection part in this embodiment detects the malfunction of a thermistor or the liquid leak of a block. It is a figure which shows the structural block of the abnormality detection apparatus in the modification of this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Battery ECU, 12 Voltage detection part, 14 Temperature detection part, 16 Abnormality detection part, 20 assembled battery, 30, 32 multiplexer, 40 temperature sensor, 42 thermistor (temperature resistance element), 44 resistance.

Claims (8)

A temperature detector for detecting a potential Vs from a reference potential of a temperature resistance element provided on the surface of the power storage device;
A voltage detector that detects a potential Vt from the reference potential of the power storage device;
An abnormality detection unit that detects a liquid leakage abnormality of the power storage device based on at least one of the potential Vs of the temperature resistance element and the potential Vt of the power storage device;
An abnormality detection device for a power storage device comprising: The abnormality detection device according to claim 1,
The abnormality detection unit
Based on the comparison between the potential Vt from the reference potential of the power storage device and the potential Vs of the temperature resistance element, the presence or absence of liquid leakage of the power storage device is determined.
An abnormality detection device characterized by the above. The abnormality detection device according to claim 1,
The abnormality detection unit
Based on the comparison between the potential Vt from the reference potential of the power storage device and the potential Vcc from the reference potential of the power source supplied to the temperature resistance element, the presence or absence of liquid leakage of the power storage device is determined.
An abnormality detection device characterized by the above. The abnormality detection device according to claim 1,
The abnormality detection unit
Based on a comparison between the reference potential and the potential Vt from the reference potential of the power storage device, the presence or absence of liquid leakage of the power storage device is determined.
An abnormality detection device characterized by the above. The abnormality detection device according to claim 1,
The power storage device is at least one battery block electrically connected in series,
The abnormality detection unit
Based on a comparison between a value obtained by multiplying a potential Vt from the reference potential of the power storage device by a coefficient determined based on the number of battery blocks constituting the power storage device, and a potential Vs of the temperature resistance element, Judging whether there is liquid leakage from the device,
An abnormality detection device characterized by the above. In the abnormality detection device according to claim 5,
The abnormality detection unit
When the number of battery blocks constituting the power storage device is M, an integer not less than 1 and not more than M is m, the coefficient is m / M, and a predetermined threshold is S, | Vs−m / M × Vt | ≦ S is satisfied. When m is present, an abnormality is detected as a leakage of the battery block connected mth from the reference potential side.
An abnormality detection device characterized by the above. A temperature detector that calculates the temperature of the power storage device based on the potential Vs from the reference potential of the temperature resistance element provided on the surface of the power storage device;
An abnormality detection unit that detects a malfunction of the temperature resistance element based on the potential Vs of the temperature resistance element and a liquid leak of the power storage device, even if the potential Vs of the temperature resistance element is within a predetermined potential range. Even when it is not included, when a liquid leakage of the power storage device is detected, an abnormality detection unit that detects an abnormality as a liquid leakage of the power storage device, not a malfunction of the temperature resistance element,
An abnormality detection device for a power storage device comprising: A temperature detector that calculates the temperature of the power storage device based on the potential Vs from the reference potential of the temperature resistance element provided on the surface of the power storage device;
An abnormality detection unit that detects an abnormality as a malfunction of the temperature resistance element when the potential Vs of the temperature resistance element is not included in a predetermined potential range, and prior to the detection of the malfunction of the temperature resistance element, An abnormality detection unit that determines whether or not there is a liquid leakage of the power storage device and detects a failure of the temperature resistance element only when the liquid leakage of the power storage device is not detected;
An abnormality detection device for a power storage device comprising:

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