JP2010045001A - Fault detecting system for power supply, and vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fault detecting system for a power supply which has a function of more certainly detecting the generation of gas from the power supply. <P>SOLUTION: The fault detecting system for a battery includes a battery pack 12 mounted to a vehicle, a battery housing case 13 housing the battery pack 12, an non-compressive liquid 23 housed in the battery housing case 13, a pressure sensor unit 41 which acquires a parameter value on the internal pressure of the battery housing case 13 (e.g., pressure change rate, pressure value), and a battery ECU 42 which outputs a fault signal when the parameter value reaches a given value. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an abnormality detection system that detects an abnormality of a power supply body and a vehicle including the abnormality detection system.

  A hybrid battery, an electric car, and a fuel cell car are equipped with a secondary battery as a driving or auxiliary power source. As a secondary battery of this type, a configuration in which an assembled battery in which a plurality of single cells are connected in series is housed in a battery pack is widely known. The single battery is provided with a safety valve. When the battery is in an abnormal state (for example, discharged with a large current or overcharged), gas may be generated inside the battery, and the internal pressure of the battery may become abnormally high. If it will be in this state, the safety valve of a cell will open and gas will be discharged to the space inside a battery pack. As a method for detecting that the safety valve has been opened, Patent Document 1 discloses the following configuration.

  Patent Document 1 discloses an abnormality warning device for a lithium ion secondary battery. The battery pack contains four lithium ion secondary batteries and a control circuit, and a pressure sensor is disposed in the space between the lithium ion secondary battery and the control circuit. This pressure sensor is connected to a control circuit. When gas is generated from the lithium ion secondary battery and the internal pressure of the battery pack rises, the pressure sensor detects this and outputs a signal to the control circuit. The control circuit outputs a signal to an alarm provided outside the battery pack and instructs the outside to issue an alarm.

  Patent Document 2 discloses a detection device that detects the state of a safety valve of a sealed battery. When the internal pressure of the battery increases, the safety valve breaks and releases the gas inside the battery. This detection device is provided integrally with a portion where the safety valve breaks, and includes a conducting wire that is disconnected when the safety valve is broken, and a detecting unit that detects a conduction state of the conducting wire. It is possible to detect that the safety valve of the battery has changed from the closed state to the open state by detecting that the conducting wire is disconnected at the time of breaking of the safety valve and the disconnection state is detected.

Patent Document 3 discloses an electric storage element module including an electric element whose electrical characteristics change when an exhaust discharged from the opened safety valve comes into contact therewith. The operating state of the safety valve is detected by detecting a change in the electrical characteristics of the electrical element.
JP 2000-123887 A JP 2005-322471 A JP 2007-265658 A

  However, since the configuration of Patent Document 1 is intended for cardiac pacemakers, the following problems arise when this is applied to an in-vehicle power supply device.

  In an in-vehicle power supply device, since the size (volume) of the battery pack is larger than that of a cardiac pacemaker, when gas is generated from the power supply element (corresponding to the lithium ion secondary battery of Patent Document 1), the inside of the battery pack The air is compressed and the pressure rise is alleviated. Therefore, as a first condition, the detection pressure of the pressure sensor must be set low so that an alarm is activated when gas is generated from the power supply element.

  On the other hand, the internal pressure of the battery pack may increase due to thermal expansion of the air inside the battery pack due to external heat or the like. In this case, since the power supply element operates normally, the detection pressure of the pressure sensor must be set high so as not to activate the alarm. That is, as a second condition, when the power supply element is operating normally, if the air inside the battery pack is thermally expanded due to external heat or the like, the detected pressure of the pressure sensor is set so that the alarm is not activated. Must be set.

  Therefore, when the pressure increase is larger in the state of thermal expansion due to external heat or the like than in the gas generation state where gas is generated from the power supply element, both the first and second conditions cannot be satisfied. That is, the detection pressure of the pressure sensor cannot be set to an appropriate value.

  Therefore, an object of the present invention is to provide an abnormality detection system for a power supply body having a function capable of more reliably detecting the generation of gas from the power supply body.

  In order to solve the above problems, an abnormality detection system for a power supply body according to the present invention includes (1) a power supply body mounted on a vehicle, a sealed container for housing the power supply body, and an uncompressed container accommodated in the sealed container And an acquisition unit for acquiring a parameter value related to the internal pressure of the sealed container, and a controller that outputs an abnormal signal when the parameter value reaches a predetermined value.

  According to the structure of (1), the said predetermined value can be set higher than the parameter value regarding the internal pressure of the said airtight container when the said incompressible liquid thermally expands in the normal state of the said power supply body. . Thereby, it is possible to prevent an abnormal signal from being output from the controller when the internal pressure of the sealed container rises due to a factor other than a power supply abnormality that generates gas from the power supply body.

  (2) In the configuration of (1), the rate of change of the internal pressure value of the sealed container can be used as the parameter value.

  (3) In the configuration of (2), the predetermined value is set to be higher than a rate of change of the internal pressure value of the sealed container when the incompressible liquid is thermally expanded in a normal state of the power supply body. Can do. Here, the “normal state” is intended to eliminate the thermal expansion of the liquid in an abnormal state where gas is generated from the power supply body due to overcharge or overdischarge.

  (4) In the configuration of (1), the internal pressure value of the closed container can be used as the parameter value.

  (5) In the configuration of (4), the predetermined value can be set higher than the internal pressure value of the sealed container when the incompressible liquid is thermally expanded in a normal state of the power supply body. Here, the “normal state” means to eliminate the thermal expansion of the liquid in an abnormal state in which gas is generated from the power source due to overcharge or overdischarge, as described above.

  (6) In the configuration of (1) to (5), the acquisition unit is disposed inside the sealed container and has a space that is isolated from the incompressible liquid; And an output unit that outputs a signal corresponding to the pressure difference.

  According to the configuration of (6), since the internal pressure value of the sealed container can be detected based on the pressure difference between the inside and outside of the tank disposed inside the sealed container, the sealed container can be detected regardless of the atmospheric pressure fluctuation outside the sealed container. The parameter value related to the internal pressure can be accurately detected.

  (7) In the configurations of (1) to (6), the incompressible liquid also serves as a cooling medium for cooling the power supply body. According to the structure of (7), the temperature rise of a power supply body can be suppressed and deterioration of a power supply body can be suppressed.

  (8) In the configuration of (7), oil can be used as the cooling medium. By using oil with high specific heat, thermal conductivity and high boiling point, the power source can be efficiently cooled.

  (9) In the configurations of (1) to (8), a protection unit that cuts off the current of the power supply body can be provided based on the abnormal signal output from the controller. According to the structure of (9), an electric current can be interrupted immediately after gas discharge from a power supply body. Thereby, the temperature rise of a power supply body can be suppressed.

  (10) In the configurations of (1) to (9), a notifying unit for notifying the abnormality of the power supply body can be provided based on the abnormality signal output from the controller. According to the configuration of (10), it is possible to notify the vehicle occupant of the abnormality immediately after releasing the gas from the power supply body.

  (11) In the configurations of (1) to (10), the power supply body can be configured from a power supply element group in which a plurality of power supply elements are connected in series. Even in a sealed container that needs to accommodate a plurality of power supply elements, an abnormality of the power supply body can be detected.

  (12) In the configuration of (11), the power supply element includes a power generation element and a case for housing the power generation element, and in the case, a valve for discharging the gas generated in the case to the outside Can be provided. Thereby, the gas generated from the power supply element can be discharged out of the case, and an increase in the internal pressure of the case can be suppressed.

  According to the present invention, it is possible to more reliably detect the generation of gas from the power supply body.

Examples of the present invention will be described below.
Example 1
FIG. 1 is a cross-sectional view of the power storage device taken along the YZ plane, and the X axis, the Y axis, and the Z axis indicate three axes that are orthogonal to each other. FIG. 2 is a cross-sectional view of the cylindrical battery taken along the YZ plane. FIG. 3 is a block diagram illustrating a circuit configuration of the battery protection unit, and illustrates an internal structure of the pressure sensor unit together with the block diagram.

  In FIG. 1, the power storage device 1 includes an assembled battery (power supply body) 12, an assembled battery 12, and a battery housing case (sealed container) 13 that houses an incompressible liquid 23. The battery housing case 13 includes a case main body 13a and an upper lid 13b. The power storage device 1 of the present embodiment is used for driving an electric vehicle, a hybrid vehicle, and a fuel cell vehicle or as an auxiliary power source.

  The assembled battery 12 is configured by connecting a plurality of cylindrical batteries (power supply elements) 122 in series. Cylindrical battery 122 is supported by a pair of battery folders 123 arranged to face each other. The battery folder 123 is formed in a flat plate shape.

Protruding terminal electrodes 131 and 132 are provided at both ends of each cylindrical battery 122.
In the pair of battery folders 123, through holes (not shown) for penetrating the terminal electrodes 131 and 132 are formed. The terminal electrodes 131 and 132 protrude from the battery folder 123 through the through holes.

  Screw grooves 131 a and 132 a are formed on the outer surfaces of the terminal electrodes 131 and 132. Cylindrical batteries 122 are connected in series via bus bars 124. The bus bar 124 is formed in a flat plate shape, and terminal electrodes 131 and 132 are inserted into openings (not shown) formed in the bus bar 124.

  By fastening the fastening nut 125 to the thread grooves 131a and 132a of the terminal electrodes 131 and 132, the bus bar 124 and the terminal electrodes 131 and 132 can be electrically and mechanically connected.

  The configuration of the cylindrical battery 122 will be described in detail with reference to FIG. A power generation element 135 is housed in a single battery case (case) 134 in a wound state.

  The power generation element 135 includes a positive electrode body 135b, a negative electrode body 135c, and a separator 135a disposed between the positive electrode body 135b and the negative electrode body 135c. Here, the positive electrode body 135b includes a current collector and a positive electrode layer formed on the surface of the current collector. The positive electrode layer can be formed on one side or both sides of the current collector. The positive electrode layer is a layer containing an active material, a conductive agent, or the like corresponding to the positive electrode.

  The negative electrode body 135c is composed of a current collector and a negative electrode layer formed on the surface of the current collector. The negative electrode layer can be formed on one side or both sides of the current collector. The negative electrode layer is a layer containing an active material, a conductive agent, or the like corresponding to the negative electrode.

  Note that an electrode (a so-called bipolar electrode) in which a positive electrode layer is formed on one surface of the current collector and a negative electrode layer is formed on the other surface of the current collector can also be used. In this embodiment, an electrolytic solution is used, but a solid electrolyte formed of particles can also be used. Examples of the solid electrolyte include a polymer solid electrolyte and an inorganic solid electrolyte.

Here, when the cylindrical battery 122 is a nickel-hydrogen battery, nickel oxide is used as the active material for the positive electrode layer, and MmNi _(5-xyz) Al _x is used as the active material for the negative electrode layer. Mn _y Co _z: can be used (Mm misch metal) hydrogen absorbing alloy or the like. When the unit cell 1 is a lithium ion battery, a lithium-transition metal composite oxide can be used as the active material for the positive electrode layer, and carbon can be used as the active material for the negative electrode layer. As the conductive agent, acetylene black, carbon black, graphite, carbon fiber, or carbon nanotube can be used.

  Disc-shaped collector plates 136 are welded to both ends of the power generation element 135 in the battery longitudinal direction (Y direction). As the current collector plate 136, an aluminum foil, a stainless steel foil, or a copper foil can be used. The current collecting plate 136 is electrically and mechanically connected to the holding plate 139 through a conductive wire 137. The holding plate 139 holds the terminal electrodes 131 and 132. A destructive valve 139 a is formed on the holding plate 139 at a position different from the position where the terminal electrodes 131 and 132 are attached. A destructive valve 139a can be formed by punching the holding plate 139.

  When the cylindrical battery 122 is overcharged, overdischarged, etc., the electrolyte contained in the power generation element 135 is electrolyzed to generate gas, and the internal pressure of the unit cell case 134 increases. When the internal pressure of the battery case 134 becomes a predetermined value (for example, 2.8 atmospheres) or more, the destructive valve 139a is destroyed and gas is released to the outside of the cylindrical battery 122. Thereby, the internal pressure rise of the cell case 134 can be suppressed. In the following description, a phenomenon in which gas is generated from the cylindrical battery 122 is referred to as battery abnormality.

When the gas is released to the outside of the cylindrical battery 122, the internal pressure value of the battery housing case 13 increases. As described above, the inside of the battery housing case 13 is filled with the incompressible liquid 23. Here, assuming that the internal pressure value of the battery housing case 13 when the battery is abnormal is P ₁ , and the internal pressure value of the battery housing case 13 when the liquid 23 is thermally expanded in a normal state of the assembled battery 12 is P ₂ , P ₁ > is P ₂ (if the inside of the battery case 13 is filled with air, the magnitude relationship is reversed and this). In order to create such an internal pressure state, in this embodiment, the inside of the battery housing case 13 is filled with an incompressible liquid 23. Details will be described later.

  A capacitor (power storage unit) may be used instead of the cylindrical battery 122. The capacitor is an electric double layer capacitor based on the principle of operation of an electric double layer generated at the interface between activated carbon and electrolyte. When activated carbon is used as a solid and an electrolytic solution (dilute sulfuric acid aqueous solution) is used as a liquid and brought into contact with each other, positive and negative electrodes are relatively distributed at very short intervals at the interface. When a pair of electrodes are immersed in an ionic solution and a voltage is applied to such an extent that electrolysis does not occur, ions are adsorbed on the surface of each electrode, and positive and negative electricity are stored (charging). When electricity is discharged to the outside, positive and negative ions leave the electrode and return to the neutralized state. Further, a square battery can be used instead of the cylindrical battery 122.

  The case body 13a is open on the upper side, and an upper lid 13b is fixed to the upper end surface of the case body 13a. A fastening hole portion (not shown) is formed in the upper end surface of the case main body 13a, and the upper lid 13b and the case main body 13a can be integrated by fastening a fastening bolt in the fastening hole portion. For the battery housing case 13, a metal having high thermal conductivity and high pressure resistance can be used. For example, an iron-based alloy or an aluminum-based alloy can be used. A plurality of radiating fins (not shown) are formed on the outer surface of the battery housing case 13. By providing a plurality of heat radiation fins, the heat radiation area of the battery housing case 13 can be increased.

  The inside of the battery housing case 13 is filled with an incompressible liquid 23. In a normal flow, the liquid is an incompressible liquid (see Kojien). In the present application, the expression “incompressible” is used for comparison with air that is easily compressed.

  Specifically, a material having high specific heat, thermal conductivity, and high boiling point, which does not corrode the battery housing case 13 and the assembled battery 12 and hardly undergoes thermal decomposition, air oxidation, electrolysis and the like is suitable. Furthermore, an electrically insulating liquid is desirable in order to prevent a short circuit between the electrode terminals. For example, a fluorinated inert liquid can be used. As the fluorine-based inert liquid, Fluorinert, Novec HFE (hydrofluorether), and Novec 1230 manufactured by 3M can be used. In addition, a liquid other than the fluorine-based inert liquid (for example, silicon oil) can be used.

  The battery housing case 13 is disposed below a passenger seat (not shown). However, it can also be arranged in a space formed between the rear seat and the trunk room.

  A pressure sensor unit (acquisition unit) 41 is provided inside the battery housing case 13. The pressure sensor unit 41 detects the internal pressure value of the battery housing case 13. The detection result by the pressure sensor unit 41 is output to the battery protection unit 44 via the signal line 48.

  The battery protection unit 44 and the pressure sensor unit 41 will be described in detail with reference to FIG. The battery protection unit 44 includes a battery ECU (controller) 42, a vehicle ECU 43, and a current interruption unit 46. The assembled battery 12, the battery housing case 13, the incompressible liquid 23, the pressure sensor unit 41, and the battery ECU 42 constitute a power supply abnormality detection system. Further, the battery ECU 42 and the vehicle ECU 43 can be configured by a single controller.

  The battery ECU 42 is electrically and mechanically connected to the pressure sensor unit 41 via a signal line 48. The battery ECU 42 is electrically and mechanically connected to the vehicle ECU 43 via a signal line 49. The battery ECU 42 is electrically and mechanically connected to the current interrupter 46 via a signal line 47.

  The battery ECU 42 monitors the internal pressure of the battery housing case 13 based on the pressure information output from the pressure sensor unit 41. If the rate of change of the internal pressure value of the battery housing case 13 exceeds a predetermined value, the battery ECU 43 and the current interrupter An abnormal signal is output to the unit 46.

Here, the predetermined value is set higher than the rate of change of the internal pressure value of the battery housing case 13 when the incompressible liquid 23 is thermally expanded. As factors for the thermal expansion of the incompressible liquid 23, charging / discharging of the battery pack 12, external heat, and the like are assumed. That is, if it meets the interior of the battery case 13 with incompressible liquid 23, the internal pressure value P ₁ of the battery case 13 at the time of battery abnormality, the battery case 13 when the liquid 23 is thermally expanded greater than the internal pressure value _{P 2.} Thereby, it is possible to prevent the battery ECU 42 from outputting an abnormal signal when the incompressible liquid 23 is thermally expanded. As a result, it is possible to prevent the current interrupting section 46 from interrupting the current and the alarm lamp 55 from being lit when the battery is normal.

  More specifically, the battery ECU 42 samples the signal output from the pressure sensor unit 41 at a cycle of 1 second. When the internal pressure value of the battery housing case 13 increases by 0.45 atm in 1 second, an abnormal signal is output. Output.

  In this embodiment, the rate of change of the internal pressure value of the battery housing case 13 when an abnormal signal is output is set to 0.45 atm. This is the case when gas is released from one cylindrical battery 122. This corresponds to the rate of change of the internal pressure value of the battery housing case 13. Therefore, it can be appropriately changed according to the size and type of the cylindrical battery 122, the volume of the battery housing case 13, and the like.

Further, in the present embodiment, based on the rate of change of the internal pressure of the battery case 13, but to output the abnormal signal, abnormal when the internal pressure value P ₁ of the battery case 13 at the time of battery abnormality reaches a predetermined value You may comprise so that a signal may be output. The predetermined value can be set to a value higher than the internal pressure value P ₂ of the battery case 13 when the liquid 23 is thermally expanded in a normal state of the battery pack 12.

  The vehicle ECU 43 is mechanically and electrically connected to the alarm lamp 55 via the signal line 51. As the alarm lamp 55, a caution lamp provided in a combination meter in front of the driver's seat can be used. The caution lamp is lit based on a signal output from the vehicle ECU 43.

  The current interrupting unit 46 includes a switching unit 46a. The power line 81 takes out the electric power of the assembled battery 12 to the outside, and a motor (not shown) is driven by the extracted electric power. The current interrupting unit 46 operates the switching unit 46a in the opening direction based on the abnormal signal output from the battery ECU 42. By operating the switching unit 46a in the opening direction, the power line 81 can be disconnected. Thereby, since discharge or charge of the assembled battery 12 is prohibited, the temperature rise of the assembled battery 12 can be suppressed.

  Next, the pressure sensor unit 41 will be described with reference to FIG. The pressure sensor unit 41 includes a tank 41 a and a strain gauge (output unit) 41 b interposed between the tank 41 a and the incompressible liquid 23. As shown in FIG. 1, the outside of the tank 41 a is filled with an incompressible liquid 23. The strain gauge 41b outputs an electrical signal corresponding to the pressure difference between the inside and outside of the tank 41a. The electrical signal output from the strain gauge 41 b is transmitted to the battery ECU 42 via the signal line 48. Gas or liquid can be enclosed in the tank 41a. Nitrogen can be used as the gas sealed inside the tank 41a. The internal pressure value of the tank 41a is set to 1 atmosphere.

  The pressure sensor unit 41 is fixed to the battery folder 123. However, since the pressure changes uniformly inside the battery housing case 13, the battery housing case 13 can be disposed in a portion other than the battery folder 123 (for example, the inner surface of the battery housing case).

  The effect of the pressure sensor unit 41 will be described in detail in comparison with a reference example. In the reference example, the internal pressure value of the battery housing case 13 is detected based on the pressure difference between the inside and outside of the battery housing case 13, and the other configurations are the same as those of the first embodiment. Further, it is assumed that the internal pressure value of the battery housing case 13 is set to 2 atmospheres on the basis of the flat ground (assuming that it is 0 m above sea level).

  In the configuration of the reference example, the internal pressure value of the battery housing case 13 is calculated by adding 1 atmosphere to the pressure difference inside and outside the battery housing case 13. At 0 m above sea level, the pressure difference between the inside and outside of the battery housing case 13 is 1 atmosphere, so the internal pressure value of the battery housing case 13 is calculated as 2 atmospheres. Here, when the vehicle moves to a high altitude (for example, 4500 m above sea level), the atmospheric pressure drops from 1 atm to 0.7 atm, so the pressure difference inside and outside the battery housing case 13 increases from 1 atm to 1.3 atm. . The internal pressure value of the battery housing case 13 is calculated as 2.3 atmospheres by adding 1 atmosphere to 1.3 atmospheres.

  That is, in the configuration of the reference example, the internal pressure value of the battery housing case 13 may be calculated higher than the actual value due to a change in atmospheric pressure. In this state, if the liquid 23 is thermally expanded and the internal pressure value of the battery housing case 13 is increased, an abnormal signal may be output from the battery ECU 42. That is, although the gas is not released from the assembled battery 12, an abnormal signal may be output from the battery ECU.

  In contrast, in the configuration of the present embodiment, a tank 41a is provided inside the battery housing case 13, and the internal pressure value of the battery housing case 13 is detected based on the pressure difference between the inside and outside of the tank 41a. Since the internal pressures of the battery housing case 13 and the tank 41a do not change due to fluctuations in atmospheric pressure, the internal pressure value of the battery housing case 13 can be accurately detected regardless of the altitude during vehicle travel. As a result, when the assembled battery 12 is normal, an abnormal signal is output from the battery ECU 42 when the internal pressure value of the battery housing case 13 increases due to fluctuations in atmospheric pressure and thermal expansion of the incompressible liquid 23. Can be prevented.

  Returning to the description of the power storage device 1 with reference to FIG. A gas discharge port 113b for discharging gas generated from the assembled battery 12 is formed in the upper lid 13b. The gas discharge port 113b is located substantially at the center of the upper lid 13b when viewed in the Z-axis direction. The inner surface of the upper lid 13b (the surface on the side in contact with the incompressible liquid 23) extends along the XY plane. However, the inner surface of the upper lid 13b can be inclined upward as it approaches the gas discharge port 113b. In this case, since the gas discharged from the assembled battery 12 travels along the inclined surface formed on the inner surface of the upper lid 13b, the gas discharge can be accelerated.

  A gas discharge pipe 15 is connected to the gas discharge port 113b. Resin and metal can be used for the gas discharge pipe 15. The gas discharge port of the gas discharge pipe 15 is provided outside the passenger compartment (for example, a quarter trim of the vehicle). A gas relief valve 21 is provided at a connection portion between the gas discharge pipe 15 and the gas discharge port 113b.

  The gas relief valve 21 operates when the internal pressure value of the battery housing case 13 reaches a predetermined value (operating pressure value), and allows the gas inside the battery housing case 13 to move to the gas discharge pipe 15. Note that the operating pressure value of the gas relief valve 21 can be set to 2.8 atm, for example.

  Next, the operation of the abnormality detection system will be described with reference to the flowchart of FIG. First, in step S101, pressure measurement by the pressure sensor unit 41 is started. The battery ECU 42 samples the pressure information output from the pressure sensor unit 41 at a cycle of 1 second, and determines whether or not the rate of change of the internal pressure value of the battery housing case 13 exceeds 0.45 atm in step S102. .

  In step S102, when the rate of change of the internal pressure value of the battery housing case 13 exceeds 0.45 atm, the process proceeds to step S103. In this case, gas is generated from the cylindrical battery 122 due to battery abnormality in the battery housing case 13. In step S102, when the internal pressure increase value of the battery housing case 13 is 0.45 atm or less, the process returns to step S101 and the monitoring of the pressure information output from the pressure sensor unit 41 is continued.

  In step S <b> 103, the battery ECU 42 outputs an abnormality signal to the vehicle ECU 43 and the current interrupting unit 46. The vehicle ECU 43 turns on the alarm lamp 55 based on the abnormality signal output from the battery ECU 42. Thereby, the battery abnormality of the assembled battery 12 can be alert | reported with respect to the passenger | crew in a vehicle interior.

  The current interrupting unit 46 switches the switching unit 46 a from the on state to the off state, and interrupts the current of the assembled battery 12. Thereby, it can suppress that the assembled battery 12 raises a temperature further.

When the internal pressure value of the battery housing case 13 further increases, the gas relief valve 21 is actuated and the gas can be discharged out of the vehicle via the gas discharge pipe 15. Thereby, an internal pressure rise can be relieved.
(Modification)
In the above-described embodiment, the alarm lamp 55 is turned on to notify the increase in the internal pressure of the battery housing case 13 (gas has been released from the assembled battery 12). For example, an increase in internal pressure of the battery housing case 13 can be notified by sound output from a speaker (notification unit) provided on the door. Further, the internal pressure increase can be notified by displaying the internal pressure increase of the battery housing case 13 on a display (notification unit) mounted on the vehicle.

  A modification of the pressure sensor unit 41 will be described with reference to FIG. FIG. 5 is a block diagram of the pressure sensor unit (acquisition unit) 71, where a solid line is a signal line and an arrow indicates a direction in which a signal flows. The pressure sensor unit 71 detects the internal pressure value of the battery housing case 13 in the internal pressure sensor 71a. The battery ECU 72 outputs an abnormal signal to the vehicle ECU 73 and the current interrupting unit 74 when the internal pressure value of the battery housing case 13 exceeds a predetermined value. The vehicle ECU 73 turns on the alarm lamp 75 based on the abnormality signal output from the battery ECU 72. Since the configuration of the vehicle ECU 73, the current interrupting unit 74, and the alarm lamp 55 is the same as that of the first embodiment, the description thereof is omitted.

  The pressure sensor unit 71 further includes an external air pressure sensor 71b that detects the external air pressure. The battery ECU 72 converts the internal pressure value of the battery housing case 13 detected by the internal pressure sensor 71a into the pressure at the reference atmospheric pressure based on the external air pressure detected by the external air pressure sensor 71b. In the above-described configuration, by taking into account fluctuations in the internal pressure of the battery housing case 13 due to the influence of the external air pressure, the battery ECU 72 is abnormal when the internal pressure value of the battery housing case 13 exceeds a predetermined value, regardless of whether it is a high altitude or a flat ground. A signal can be output.

Specifically, the external air pressure is detected by the external air pressure sensor 71b, and the internal pressure value of the battery housing case 13 detected by the internal pressure sensor 71a based on the external air pressure is converted into a pressure at the reference atmospheric pressure by the battery ECU 72. That is, it is assumed that the external air pressure detected by the external air pressure sensor 71b is P ₁₀ in absolute pressure, and the gauge pressure inside the battery housing case 13 detected by the internal pressure sensor 71a at this time is P ₁₁ . On the other hand, if the reference atmospheric pressure as an absolute pressure and P _12, the internal pressure value P ₁₃ of the battery case 13 after the pressure correction,
P ₁₃ = (P ₁₀ + P ₁₁ ) −P ₁₂ (1)
Can be represented.

For example, the reference atmospheric pressure _{P 12} and 1 atm, if the internal pressure value _{P 11} of the battery case 13 to the outside air pressure _{P 10} is measured at highlands 0.8 atm was 2 atm P from (1) ₁₃ = (0.8 + 2) -1 = 1.8 atm.

If the internal pressure value _{P 11} of the battery case 13 to the outside air pressure _{P 10} is measured by the level ground 1 atm was 1.8 _{atm, P 13 = (1 + 1.8} ) -1 = 1 by (1). 8 atm.

  According to the above-described configuration, the internal pressure value of the battery housing case 13 can be accurately detected regardless of fluctuations in the external air pressure. Thereby, when the pressure rises due to a factor other than battery abnormality, it is possible to prevent the abnormality signal from being output from the battery ECU 72.

In the above-described configuration, the inside of the battery housing case 13 is filled with the incompressible liquid 23. However, the incompressible liquid 23 may be filled so as to provide a slight air layer. However, the internal pressure value P ₂ of the battery case 13 at the time of thermal expansion, so as not higher than the internal pressure value P ₁ of the battery case at the time of battery abnormality, it is necessary to set the volume of the air layer.

It is sectional drawing of an electrical storage apparatus. It is sectional drawing of a cylindrical battery. It is a block diagram which shows the circuit structure of a battery protection part, and has shown the internal structure of the pressure sensor part. It is the flowchart which showed operation | movement of the abnormality detection system. It is the block diagram which illustrated the modification of the pressure sensor part.

Explanation of symbols

12 battery pack (power supply)
13 Battery storage case (sealed container)
23 Incompressible liquid 41 Pressure sensor part (acquisition part)
42 Battery ECU (controller)

Claims (13)

A power supply mounted on the vehicle;
A sealed container for housing the power supply body;
An incompressible liquid contained in the sealed container;
An acquisition unit for acquiring a parameter value related to the internal pressure of the sealed container;
A controller that outputs an abnormal signal when the parameter value reaches a predetermined value;
An abnormality detection system for a power supply unit comprising:   The power supply unit abnormality detection system according to claim 1, wherein the parameter value is a change rate of an internal pressure value of the sealed container.   The power supply body according to claim 2, wherein the predetermined value is higher than a rate of change of an internal pressure value of the sealed container when the incompressible liquid is thermally expanded in a normal state of the power supply body. Anomaly detection system.   The system according to claim 1, wherein the parameter value is an internal pressure value of the sealed container.   The abnormality detection of the power supply unit according to claim 4, wherein the predetermined value is higher than an internal pressure value of the sealed container when the incompressible liquid is thermally expanded in a normal state of the power supply unit. system.   The acquisition unit includes a tank that is disposed inside the sealed container and has a space isolated from the incompressible liquid, and an output unit that outputs a signal corresponding to a pressure difference between the inside and the outside of the tank. The abnormality detection system for a power supply body according to any one of claims 1 to 5.   The power supply body abnormality detection system according to claim 1, wherein the incompressible liquid also serves as a cooling medium for cooling the power supply body.   The power supply body abnormality detection system according to claim 7, wherein the cooling medium is oil.   The power supply unit abnormality detection system according to any one of claims 1 to 8, further comprising a protection unit that cuts off a current of the power supply unit based on an abnormality signal output from the controller.   The power supply unit abnormality detection system according to any one of claims 1 to 9, further comprising a notification unit configured to notify an abnormality of the power supply unit based on an abnormality signal output from the controller.   The power supply unit abnormality detection system according to claim 1, wherein the power supply unit includes a power supply element group in which a plurality of power supply elements are connected in series.   Each of the power supply elements includes a power generation element and a case for housing the power generation element, and the case is formed with a valve for discharging gas generated in the case to the outside. The abnormality detection system for a power supply body according to claim 11. A vehicle equipped with the abnormality detection system for a power source body according to any one of claims 1 to 12.

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