JP2006139928A - Battery system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery system capable of short-circuiting a serial connection in a battery module and separating thin batteries from each other even when a large acceleration is impressed. <P>SOLUTION: The battery system is composed of a battery module 30, in which terminals of one side having the same polarity out of electrode terminals 104 or 105 of each of the thin batteries arrayed in plurality are electrically connected to each other by a pair of bus bars 21, a plurality of sub assemblies 20a to 20j each composed of the thin battery and the bus bar pair are laminated and electrically connected to each other, and the plurality of sub assemblies 20a to 20j are airtightly stored in a box 31; an acceleration sensor detecting the acceleration impressed on the battery module 30; a bellows 32 expanding the box 31 by air; an expansion rubber 38 expanded by the air to enlarge a space S; a cooling device supplying the air to the inside of the box 31 and the expansion rubber 38; and a controller controlling the cooling device depending on the detected acceleration. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a battery system including a battery module configured by stacking a plurality of thin batteries.

  A plurality of thin batteries in which a positive electrode terminal and a negative electrode terminal are led out from the outer peripheral edge of the battery exterior are arranged side by side, and one of the thin electrode is connected in parallel by a pair of bus bars. Conventionally, a battery module in which a plurality of subassemblies including these thin batteries and bus bar pairs are stacked and electrically connected in series is known (for example, see Patent Document 1).

Such a battery module can be used for vehicles such as an electric vehicle (EV), a fuel cell vehicle (FCV), and a hybrid electric vehicle (HEV). A large acceleration may be applied to the battery module mounted on the vehicle, for example, when the vehicle suddenly stops.
JP 2004-55492 A

The present invention more effectively prevents the battery module from entering the vehicle compartment even when a large acceleration is applied, and peels off the connection portion between the thin battery and the bus bar in the battery module. An object of the present invention is to provide a battery system capable of short-circuiting series connections and separating thin batteries.
In order to achieve the above object, according to the present invention, a plurality of thin batteries in which a positive electrode terminal and a negative electrode terminal are led out from the outer peripheral edge of the battery exterior are arranged side by side. The same-polarity terminals are electrically connected in parallel by a pair of bus bars, and a plurality of subassemblies consisting of these thin batteries and bus bar pairs are stacked and electrically connected in series, and the plurality of subassemblies are hermetically sealed inside the housing. A battery module housed in a state; acceleration detecting means for detecting an acceleration applied to an object on which the battery module is mounted; and expansion means capable of being expanded by a fluid and expanding a predetermined portion of the battery module A fluid supply means for supplying fluid to the expansion means, and a control means for controlling the fluid supply means based on the detection result of the acceleration detection means When, the battery system with a provided.

  In the present invention, the acceleration applied to the object on which the battery module is mounted is detected by the acceleration detection means, and the control means controls the fluid supply means based on the detection result, and the fluid supply means according to the control command. Supplies fluid to the expansion means, and the expansion means is expanded by the fluid to expand a predetermined portion of the battery module.

  When acceleration is applied to the object to be mounted, a predetermined part of the battery module is expanded to absorb the acceleration applied to the battery module by the expanded part, or the thin battery terminal inside the battery module The joint with the bus bar can be peeled off.

  By absorbing the acceleration by the expansion part, it is possible to more effectively prevent the battery module from entering the vehicle interior. In addition, the expansion means expands the thin battery and the bus bar so that the thin battery can be separated from each other by short-circuiting the serial connection in the battery module.

BEST MODE FOR CARRYING OUT THE INVENTION

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, the thin battery which comprises a battery module in embodiment of this invention is demonstrated. FIG. 1 is a plan view of an entire thin battery according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II in FIG. 1 and 2 show one thin battery 10 (unit battery), and a battery having a desired voltage and capacity is configured by connecting a plurality of the thin batteries 10.

  A thin battery 10 according to an embodiment of the present invention is a flat plate-like lithium ion secondary battery that can be stacked. As shown in FIGS. 1 and 2, three positive plates 101, five separators 102, It comprises three negative plates 103, a positive electrode terminal 104, a negative electrode terminal 105, an upper exterior member 106, a lower exterior member 107, and an electrolyte (not shown), and has a total thickness of, for example, 10 mm or less. Have. Among these, the positive electrode plate 101, the separator 102, the negative electrode plate 103, and the electrolyte are particularly referred to as a power generation element 108.

  The positive electrode plate 101 constituting the power generation element 108 includes a positive electrode current collector 101a extending to the positive electrode terminal 104, and positive electrode layers 101b and 101c formed on both main surfaces of a part of the positive electrode current collector 101a, respectively. And have.

  The positive electrode side current collector 101a of the positive electrode plate 101 is, for example, an electrochemically stable metal foil such as an aluminum foil, an aluminum alloy foil, a copper foil, or a nickel foil.

The positive electrode layer 101b of the positive electrode plate 101, 101c, for example lithium-nickel composite oxide such as LiNiO _2, lithium-manganese-based composite oxide such as LiMn ₂ O _4, or a lithium-cobalt composite oxide such as LiCoO _2, A mixture of a positive electrode active material such as an oxide or a chalcogen (S, Se, Te) compound, a conductive agent such as carbon black, and a binder such as an aqueous dispersion of polyfluorinated ethylene. It is formed by applying to both main surfaces of a part of the current collector 101a, drying and compressing.

  The negative electrode plate 103 constituting the power generation element 108 includes a negative electrode side current collector 103a extending to the negative electrode terminal 105, and negative electrode layers 103b and 103c formed on both main surfaces of a part of the negative electrode side current collector 103a, respectively. And have.

  The negative electrode side current collector 103a of the negative electrode plate 103 is an electrochemically stable metal foil such as a nickel foil, a copper foil, a stainless steel foil, or an iron foil.

  The negative electrode layers 103b and 103c of the negative electrode plate 103 include negative electrode actives that occlude and release lithium ions of the positive electrode active material, such as amorphous carbon, non-graphitizable carbon, graphitizable carbon, or graphite. Mainly a substance in which an aqueous dispersion of a styrene butadiene rubber resin powder as a precursor material of an organic fired body is mixed with a substance, dried, and pulverized to carry carbonized styrene butadiene rubber on the surface of carbon particles. The material is formed by further mixing a binder such as an acrylic resin emulsion with the mixture, applying the mixture to both main surfaces of a part of the negative electrode side current collector 103a, and drying and compressing the mixture.

  In particular, when amorphous carbon or non-graphitizable carbon is used as the negative electrode active material, the flatness of the potential during charge / discharge is poor and the output voltage decreases with the amount of discharge. Although unsuitable, it is advantageous when used as a power source for an electric vehicle because there is no sudden drop in output.

  The separator 102 of the power generation element 108 prevents a short circuit between the positive electrode plate 101 and the negative electrode plate 103 described above, and may have a function of holding an electrolyte. This separator 102 is a microporous film made of polyolefin such as polyethylene (PE) or polypropylene (PP), for example. When an overcurrent flows, the pores of the layer are blocked by the heat generation and the current is cut off. It also has a function to

  The separator 102 of the present invention is not limited to a single-layer film such as polyolefin, but may be a three-layer structure in which a polypropylene film is sandwiched with a polyethylene film, or a laminate of a polyolefin microporous film and an organic nonwoven fabric or the like. I can do it. Thus, by making the separator 102 into multiple layers, various functions such as an overcurrent prevention function, an electrolyte holding function, and a separator shape maintenance (stiffness improvement) function can be provided.

  In the power generation element 108 described above, the positive electrode plates 101 and the negative electrode plates 103 are alternately stacked via the separators 102. The three positive plates 101 are respectively connected to the positive terminal 104 made of metal foil via the positive current collector 101a, while the three negative plates 103 are connected to the negative current collector 103a. In the same manner, each is connected to a negative electrode terminal 105 made of metal foil.

  In addition, the positive electrode plate 101, the separator 102, and the negative electrode plate 103 of the power generation element 108 are not limited to the above number in the present invention. For example, one positive electrode plate 101, three separators 102, and 1 The power generation element 108 can also be configured with a single negative plate 103, and can be configured by selecting the number of positive plates, separators, and negative plates as required.

  The positive electrode terminal 104 and the negative electrode terminal 105 are not particularly limited as long as they are electrochemically stable metal materials. Examples of the positive electrode terminal 104 include, for example, an aluminum foil and an aluminum alloy foil, similar to the positive electrode current collector 101a described above. , Copper foil, or nickel foil. Moreover, as the negative electrode terminal 105, nickel foil, copper foil, stainless steel foil, iron foil, etc. can be mentioned similarly to the above-mentioned negative electrode side collector 103a, for example.

  The power generation element 108 is accommodated and sealed in the upper exterior member 106 and the lower exterior member 107. The upper exterior member 106 and the lower exterior member 107 in the present embodiment are not particularly illustrated, but are excellent in electrolytic solution resistance and heat fusion properties such as polyethylene and polypropylene from the inside to the outside of the thin battery 10. An inner layer composed of a resin film, an intermediate layer composed of a metal foil such as aluminum, and a resin film excellent in electrical insulation such as a polyamide resin or a polyester resin. It is composed of a resin-metal thin film laminate material having a three-layer structure including an outer layer.

These exterior members 106 and 107 enclose the power generation element 108, a part of the positive electrode terminal 104 and a part of the negative electrode terminal 105, and in the space formed by the exterior members 106 and 107, perchloric acid is added to the organic liquid solvent. While injecting a liquid electrolyte in which a lithium salt such as lithium (LiClO ₄ ), lithium borofluoride (LiBF ₄ ), or lithium hexafluorophosphate (LiPF ₆ ) is used as a solute, a space formed by the exterior members 106 and 107 is formed. The exterior members 106 and 107 are heat-sealed by hot pressing along their outer peripheral edges and sealed in a vacuum state by suction.

  Examples of the organic liquid solvent include ester solvents such as propylene carbonate (PC), ethylene carbonate (EC), dimethyl carbonate (DMC), and methyl ethyl carbonate (MEC). Without being limited thereto, an ether solvent such as γ-butylactone (γ-BL), dietoshikiethane (DEE), or other mixed or prepared organic liquid solvent can be used as the ester solvent.

  In the present embodiment, the battery module 30 is formed by connecting a plurality of the thin batteries 10 described above, and a specific structure thereof will be described with reference to FIGS.

  3 is a partially exploded perspective view showing the battery module according to the embodiment of the present invention, FIG. 4 is a schematic sectional view of the battery module according to the first embodiment of the present invention, and FIG. 5 is an external view of the battery module according to the embodiment of the present invention. It is a perspective view shown.

  In the battery module 30 according to the embodiment of the present invention, as shown in FIG. 3, four thin batteries 10 are electrically connected in parallel to form sub-assemblies 20a to 20j. That is, the positive terminals 104 of the four thin batteries 10 are connected to one bus bar 21 in such a posture that the same polarity terminals 104, 105 of the four thin batteries 10 face in the same direction, and the negative terminals 105 are connected to each other. Connect to another bus bar 21. The connection between the electrode terminal 104 or 105 and the bus bar 21 is not specifically limited as long as it is electrically connected. For example, welding can be performed. The bus bar 21 is a flat plate member made of a material having excellent conductivity, such as copper, nickel, and stainless steel. When the four thin batteries 10 are arranged side by side, the four homopolar terminals 104 or 105 are connected to the bus bar 21. Has a connectable length.

  Ten subassemblies 20a-20j configured by connecting bus bars 21 in parallel to the same polarity terminals 104, 105 of the four thin batteries 10 are stacked as shown in FIGS. The assemblies 20a to 20j are stacked so as to be sequentially connected in series. That is, the subassembly 20a and the subassembly 20b in the next stage are configured so that the lead-out direction of the negative electrode terminal 105 in the subassembly 20a and the leadout direction of the positive terminal 104 in the subassembly 20b in the next stage are substantially the same. Are stacked.

  Similarly, in the subassembly 20b and the subassembly 20c in the next stage, the lead-out direction of the negative electrode terminal 105 in the subassembly 20b and the leadout direction of the positive terminal 104 in the subassembly 20c in the next stage are substantially the same. Are stacked. That is, the n-stage so that the lead-out direction of the electrode terminals 104 and 105 in the n-th subassembly from the top is substantially the same as the lead-out direction of the different polarity terminals 105 and 104 in the (n + 1) -th subassembly. The sub-assembly of the eye and the sub-assembly of the (n + 1) th stage are stacked (where n is a natural number).

  In the present embodiment, as shown in FIG. 4, the bus bar 21 connecting the negative terminals 105 of the subassembly 20a stacked in the upper stage and the positive terminals 104 of the subassembly 20b stacked in the lower stage are connected. The bus bar 21 is also used. Therefore, a space S surrounded by these is formed between the negative terminal 105 of the upper subassembly 20a, the bus bar 21, and the positive terminal 104 of the lower subassembly 20b.

  Similarly, the bus bar 21 that joins the negative terminals 105 of the sub-assembly 20b and the bus bar 21 that connects the positive terminals 104 of the sub-assembly 20c stacked below the bus bar 21 are also used. A space S is formed between them. That is, the bus bar 21 that joins the negative terminals 105 of the n-th sub-assembly and the bus bar 21 that joins the positive terminals 104 of the sub-assemblies stacked on the lower stage are also used. A space S is formed between them.

  Furthermore, in this embodiment, as shown in FIG. 4, an expansion rubber 38 (expansion member) is disposed in each space S. The inflatable rubber 38 is made of a material having excellent flexibility, such as synthetic rubber, and has a shape that can be inflated in a balloon shape. Each expansion rubber 38 is connected to the expansion valve 36 via a gas injection tube 37, and can be expanded by the air supplied from the cooling device 50 to expand the space S.

  Note that the bus bar 21 connecting the positive terminals 104 in the uppermost subassembly 20a is not shared with the bus bar connecting the electrode terminals of other subassemblies. Instead, the bus bar 21 is connected to a positive electrode side external terminal 33 for electrically connecting the battery module 30 to the outside. Similarly, the bus bar 21 that connects the negative electrode terminals 105 of the lowermost subassembly 20j is not used as the bus bar that connects the electrode terminals of other subassemblies. Instead, the bus bar 21 is connected to a negative external terminal 34 for electrically connecting the battery module 30 to the outside.

  As described above, the ten subassemblies 20a to 20j electrically connected in series are accommodated in the housing 31. The casing 31 is made of a material having excellent electrical insulation, such as synthetic resin, and can accommodate ten subassemblies 20a to 20j in an airtight state.

  In the housing 31 in the present embodiment, as shown in FIGS. 4 and 5, a bellows 32 (bellows portion) is provided in a part of the housing 31, and a predetermined direction (white in FIGS. 4 and 5). The casing 31 can be expanded and contracted in the direction of the arrow). Note that FIG. 3 does not show the side surface of the housing 31 on which the bellows 32 is formed.

  As shown in FIGS. 3 to 5, a cooling duct 35 and an expansion valve 36 are attached to the front surface of the housing 31. On the other hand, the external terminals 33 and 34 described above are provided on the rear surface of the casing 31. It should be noted that a discharge port for discharging the cooling air may be formed on the back surface of the housing 31 in order to improve the ventilation of the cooling air.

  The cooling duct 35 can communicate with the inside of the casing 31, and in normal use, the cooling duct 35 sends air supplied from a cooling device 50 to be described later as cooling air into the casing 31. Each thin battery 10 included in the ten subassemblies 20a to 20j accommodated in the interior 31 can be cooled.

  The expansion valve 36 is a switching valve capable of switching the air supply destination to either the expansion rubber 38 or the inside of the housing 31, and a gas injection tube 37 communicating with each expansion rubber 38 is provided at one outlet. While being connected, the other outlet is directly opened toward the inside of the housing 31. The expansion valve 36 can switch the air supply destination to either the expansion rubber 38 or the inside of the casing 31 according to the control of the controller 60 of the battery system 1 described later. By connecting the cooling device 50 and the expansion rubber 38 with the expansion valve 36, air is supplied to the expansion rubber 38 and the space S can be expanded. On the other hand, by connecting the cooling device 50 and the inside of the casing 31 with the expansion valve 36, air is supplied into the casing 31 and the bellows 32 can be extended to expand the casing 31 itself.

  Next, a battery system according to this embodiment using the battery module 30 described above will be described. FIG. 6 is a block diagram showing the overall configuration of the battery system according to the first embodiment of the present invention, and FIG. 7 is a schematic diagram showing an electric vehicle equipped with the battery system according to the first embodiment of the present invention.

  As shown in FIG. 6, the battery system 1 according to the first embodiment of the present invention is applied to the battery module 30 having the ten subassemblies 20a to 20j and the electric vehicle C (mounting object) as described above. An acceleration sensor 40 for detecting acceleration, a cooling device 50 for cooling the battery module 30 during normal driving, a cooling device power supply 51 for supplying power to the cooling device 50, and air of the cooling device 50 A main valve 52 that switches the supply destination, and a controller 60 that controls switching of the fan rotation speed of the cooling device 50 and the valves 36 and 52 based on the detection result of the acceleration sensor 40 are provided. In FIG. 6, the air flow is indicated by a solid line, the flow of the acceleration detection signal and the control command signal is indicated by a one-dot chain line, and the power flow is indicated by a two-dot chain line.

  As shown in FIG. 7, the acceleration sensor 40 of the battery system 1 is installed in the front part of the electric vehicle C, and can detect the acceleration applied when the electric vehicle C is suddenly stopped. It has become. The acceleration sensor 40 is connected to the controller 60, and the detection result can be sent to the controller 60.

  As shown in the figure, the cooling device 50 of the battery system 1 is installed in the rear part of the electric vehicle C together with the battery module 30. For example, the cooling air is supplied to the battery module 30 via the cooling duct 35 by a cooling fan or the like. It is possible to supply. The cooling air supplied through the cooling duct 35 enters the inside of the casing 31 of the battery module 30 and cools by passing between the thin batteries 10. The cooling device 50 is provided with a motor (not shown) for rotating the cooling fan, and power is supplied to the motor from the cooling device power supply 51.

  The main valve 52 of the battery system 1 is provided in a communication path that connects the cooling device 50 and the cooling duct 35 of the battery module 30. The main valve 52 is a switching valve capable of switching the air supply destination of the cooling device 50, and one outlet communicates with the cooling duct 35 via the communication path, whereas the other outlet It communicates with the expansion valve 36 of the battery module 30 through the communication path. The main valve 52 can switch the air supply destination of the cooling device 50 to either the cooling duct 35 or the expansion valve 36 under the control of the controller 60.

  Below, the expansion operation process of the battery system 1 according to the present embodiment when a large acceleration is applied, for example, when the electric vehicle C suddenly stops will be described. FIG. 8 is a flowchart showing an expansion operation process in the battery system according to the first embodiment of the present invention.

  As a precondition, when the electric vehicle C is traveling normally, the main valve 52 is switched so as to supply the air of the cooling device 50 to the cooling duct 35, and the air supplied from the cooling device 50 is the battery module. This is used as cooling air for cooling 30. Further, the expansion valve 36 in the initial state is switched so as to communicate with each expansion rubber 38 via the gas injection tube 37, and does not communicate with the inside of the housing 31.

  For example, when a large acceleration is applied due to, for example, a sudden stop of the electric vehicle C, first, the acceleration sensor 40 detects the acceleration in step S10 of FIG.

  The detection result by the acceleration sensor 40 is sent to the controller 60. Based on the detection result, the controller 60 controls the main valve 52 so that the air supply destination of the cooling device 50 is switched from the cooling duct 35 to the expansion valve 36 (step S20). As a determination method of switching of the main valve 52 in the controller 60, for example, a method of comparing a detection result with a predetermined threshold value and determining whether the detection result is larger than the threshold value can be cited.

  Next, the controller 60 controls the cooling device 50 so as to increase the rotation speed of the cooling fan (step S30). The air supplied from the cooling device 50 to the expansion valve 36 via the main valve 52 is further supplied to each expansion rubber 38 via the gas injection tube 37, whereby the internal pressure of each expansion rubber 38 increases. The expansion is started (step S40).

  When each expansion rubber 38 is expanded by the air supplied from the cooling device 50, each space S surrounded by the bus bars 21 and the terminals 104 and 105 is expanded in the battery module 30. Here, since the joint portion between the electrode terminals 104 and 105 and the bus bar 21 has a structure that is weak against external force, the joint portion is easily peeled off by the expansion of the space S due to the expansion of the expansion rubber 38, and the electrode terminal. 104 and 105 and the bus bar 21 are electrically disconnected (step S50).

  As described above, in the battery system 1 according to the present embodiment, the expansion rubber 38 is expanded using the air supplied from the cooling device 50 as the expansion air. Then, by expanding the expansion rubber 38 and expanding the space S, the joint portion between the electrode terminals 104 and 105 of the thin battery 10 and the bus bar 21 is peeled off. Thereby, the serial connection in a battery module is short-circuited, and thin batteries can be separated from each other.

  As another method for electrically separating the thin batteries of the battery module, a method using a relay or the like is conceivable, but in this case, the reliability of disconnection of the relay is not so high. On the other hand, in the battery system according to the present embodiment, since the joint portion itself is physically peeled off, the reliability is improved.

  When the joint between the electrode terminals 104 and 105 and the bus bar 21 is peeled off (when a sufficient amount of inflation air is supplied to peel off the joint), the controller 60 injects the supply destination of the inflation air. A control command is sent to the expansion valve 36 so as to switch from the tube 37 to the inside of the housing 31. The expansion valve 36 supplies expansion air into the housing 31 in accordance with this control command. At this time, since the rotation speed of the cooling fan is increased in the above-described step S30, the internal pressure of the casing 31 is increased, and the bellows 32 is extended in a predetermined direction (the direction of the white arrow in FIGS. 4 and 5). Then, the casing 31 is expanded (step S60).

  In the case where a discharge port is formed on the rear surface of the casing 31, an opening / closing valve is provided at the discharge port, and the opening / closing valve is closed simultaneously with the switching control of the expansion valve 36 in step S20. May be performed. Thereby, the internal pressure of the housing | casing 31 can be raised rapidly.

  As described above, in the battery system 1 according to the present embodiment, the air supplied from the cooling device 50 is used as expansion air to increase the internal pressure of the housing 31 and extend the bellows 32, thereby Inflate. Since the applied acceleration can be absorbed by the casing 31 thus expanded, it is possible to more effectively prevent the battery module 30 from entering the vehicle interior.

[Second Embodiment]
FIG. 9 is a block diagram showing the overall configuration of the battery system according to the second embodiment of the present invention, and FIG. 10 is a flowchart showing expansion operation processing in the battery system according to the second embodiment of the present invention. In FIG. 9, the flow of air is indicated by a solid line, the flow of hydrogen is indicated by a dotted line, the flow of acceleration detection signals and control command signals is indicated by a one-dot chain line, and the flow of power is indicated by a two-dot chain line.

  In the second embodiment of the present invention, a battery system when applied to a fuel cell vehicle (mounted object) that travels by generating power with a fuel cell 70 that generates power with hydrogen and oxygen and driving a drive motor M is provided. explain.

  As shown in FIG. 9, the battery system 1 ′ according to the present embodiment includes a battery module 30, an acceleration sensor 40, a cooling device 50, a cooling device power supply 51, a main valve 52, and a controller 60. Although common to the battery system 1 according to the first embodiment, the fuel system 70 includes a fuel cell 70, a hydrogen tank 71, a compressor motor 72, hydrogen valves 73 and 74, and air valves 75 and 76. It is different from the embodiment. Further, in the battery system 1 ′ according to the present embodiment, the controller 60 is common to the first embodiment in that the controller 60 can control the expansion valve 36, the main valve 52, and the cooling device 50. In addition, It is different in that the valves 73 to 76 can be controlled. Regarding the battery system 1 ′ according to the second embodiment, description of points that are common to the battery system 1 according to the first embodiment is omitted, and points that are different from the battery system 1 according to the first embodiment are described below. .

  The fuel cell 70 is a fuel cell that generates electricity by electrochemically reacting hydrogen and oxygen in the presence of a catalyst, and the vehicle is driven by driving a driving motor M with the electric power generated by the fuel cell 70. Run. The hydrogen tank 71 stores a hydrogen-rich hydrogen-containing gas supplied to the fuel cell 70. The compressor motor 72 can supply an oxygen-containing gas (air) to the fuel cell 70.

  As shown in FIG. 9, a first hydrogen valve 73 is provided in the communication path between the hydrogen tank 71 and the fuel cell 70. The first hydrogen valve 73 is a switching valve for switching the supply destination of the hydrogen-containing gas in the hydrogen tank 71, and one outlet is directly connected to the hydrogen inlet of the fuel cell 70, while the other The outlet communicates with the expansion valve 36 of the battery module 30 through the communication path. The first hydrogen valve 73 can switch the supply destination of the hydrogen-containing gas in the hydrogen tank 71 to either the fuel cell 70 or the battery module 30 under the control of the controller 60.

  Further, a second hydrogen valve 74 is provided in the communication path between the first hydrogen valve 72 and the expansion valve 36 of the battery module 30. The second hydrogen valve 74 is an open / close valve that opens and closes the communication path, and allows the first hydrogen valve 73 and the battery module 30 to communicate with each other under the control of the controller 60.

  As shown in the figure, a first air valve 75 is provided in the communication path between the compressor motor 72 and the fuel cell 70. The first air valve 75 is a switching valve for switching the air supply destination of the compressor motor 72. One outlet is directly connected to the oxygen inlet of the fuel cell 70, whereas the other outlet is connected. It communicates with the expansion valve 36 of the battery module 30 through the communication path. The first air valve 75 can switch the air supply destination of the compressor motor 72 to either the fuel cell 70 or the battery module 30 under the control of the controller 60.

  Further, a second air valve 76 is provided in the communication path between the first air valve 75 and the expansion valve 36 of the battery module 30. The second air valve 76 is a switching valve that switches a supply source of air to the battery module 30. One inlet is in communication with the cooling device 50 through the communication path, whereas the other inlet is Communicates with the first air valve 75 via the communication path. The second air valve 76 can switch the supply source of air to the battery module 30 to either the cooling device 50 or the compressor motor 72 according to the control of the controller 60.

  The main valve 52 described in detail in the first embodiment is provided in a communication path between the second air valve 76 and the expansion valve 36 of the battery module 30, and, as in the first embodiment, The other outlet communicates with the expansion valve 36 of the battery module 30 via the communication path, whereas the other outlet communicates with the cooling duct 35 of the battery module 30 via the communication path.

  Hereinafter, an expansion operation process of the battery system 1 ′ according to the present embodiment when a large acceleration is applied, for example, when the fuel cell vehicle suddenly stops will be described with reference to FIG. 10.

  As a precondition, in a state where the fuel cell vehicle is normally running, the first hydrogen valve 73 is switched and the second hydrogen is supplied so that the hydrogen-containing gas is supplied from the hydrogen tank 71 to the fuel cell 70. Valve 74 is closed. The first air valve 75 is switched so that air is supplied from the compressor motor 72 to the fuel cell 70, and the second air is supplied so that cooling air is supplied from the cooling device 50 to the battery module 30. The air valve 76 and the main valve 52 are switched. Similarly to the first embodiment, the expansion valve 36 in the initial state is set so as to communicate with each expansion rubber 38 via the gas injection tube 37, and communicates with the inside of the housing 31. Absent.

  For example, when a large acceleration is applied due to, for example, a sudden stop of the fuel cell vehicle, the acceleration sensor 40 first detects the acceleration in step S110 of FIG.

  The detection result by the acceleration sensor 40 is sent to the controller 60. The controller 60 performs control to switch the main valve 52, the hydrogen valves 73 and 74, and the air valves 75 and 76 based on the detection result (step S120).

  Specific valve switching operations of the valves 52 and 73 to 76 in step S120 are as follows. That is, the main valve 52 switches the air supply destination from the cooling duct 35 of the battery module 30 to the expansion valve 36 of the battery module 30. The first hydrogen valve 73 switches the supply destination of the hydrogen-containing gas from the fuel cell 70 to the battery module 30, and the second hydrogen valve 74 opens the communication path. The first air valve 75 switches the air supply destination from the fuel cell 70 to the battery module 30, and the second air valve 76 switches the air supply source from the cooling device 50 to the compressor motor 72.

  As a method for determining the switching of the valves 52 and 73 to 76 in the controller 60, for example, a method of comparing the detection result with a predetermined threshold can be cited as in the first embodiment.

  Next, the controller 60 controls the cooling device 50 to stop the rotation of the cooling fan (step S130).

  On the other hand, the hydrogen-containing gas supplied from the hydrogen tank 71 through the hydrogen valves 73 and 74 to the expansion valve 36 of the battery module 30 and the battery module from the compressor motor 72 through the oxygen valves 75 and 76. The air supplied to the expansion valve 36 is further supplied to each expansion rubber 38 via the gas injection tube 37 in the battery module 30 (step S140), whereby the internal pressure of each expansion rubber 38 is increased. Ascend and start expanding (step S150).

  When each expansion rubber 38 is expanded by the hydrogen-containing gas and air supplied as described above, each space S surrounded by each bus bar 21 and the different polarity terminals 104 and 105 in the battery module 30 is expanded. Here, since the joint portion between the electrode terminals 104 and 105 and the bus bar 21 has a structure that is weak against external force, the joint portion is easily peeled off by the expansion of the space S due to the expansion of the expansion rubber 38, and the electrode terminal. 104 and 105 and the bus bar 21 are electrically disconnected (step S160).

  Thus, in the battery system 1 ′ according to the present embodiment, the expansion rubber 38 is expanded by using the hydrogen-containing gas and air supplied to the fuel cell 70 as the expansion fluid. Then, by expanding the expansion rubber 38 and expanding the space S, the joint portion between the electrode terminals 104 and 105 of the thin battery 10 and the bus bar 21 is peeled off. Thereby, the serial connection in a battery module is short-circuited, and thin batteries can be separated from each other.

  When the joint between the electrode terminals 104 and 105 and the bus bar 21 is peeled off (when a sufficient amount of hydrogen-containing gas and air is supplied to peel off the joint), the controller 60 supplies the hydrogen-containing gas and air. A control command is sent to the expansion valve 36 so that the tip is switched from the gas injection tube 37 to the inside of the housing 31. The expansion valve 36 switches the valve in accordance with this control command and supplies the expansion air into the housing 31. At this time, in step S120, the valves 52 and 73 to 76 are switched so that the hydrogen-containing gas and air are supplied to the battery module 30 from the hydrogen tank 71 and the compressor motor 72. The internal pressure rises, the bellows 32 extends in a predetermined direction, and the housing 31 expands (step S170).

  As described above, in the battery system 1 ′ according to the present embodiment, the hydrogen containing gas or air supplied from the hydrogen tank 71 or the compressor motor 72 provided for the fuel cell 70 is used as the expansion fluid. The casing 31 is inflated by increasing the internal pressure of 31 and extending the bellows 32. Since the applied acceleration can be absorbed by the casing 31 thus expanded, it is possible to more effectively prevent the battery module 30 from entering the vehicle interior.

[Third Embodiment]
FIG. 11 is a diagram showing an overall configuration of a battery system according to the third embodiment of the present invention, and FIG. 12 is a flowchart showing expansion operation processing in the battery system according to the third embodiment of the present invention. In FIG. 11, the flow of the exhaust gas is shown by a solid line, and the flow of the acceleration detection signal and the control command signal is shown by a one-dot chain line.

  In the third embodiment of the present invention, a hybrid electric vehicle (mounting object) that includes an engine 80 as a power source and a drive motor (not shown) as a power source and that is operated simultaneously or individually depending on the situation. The battery system 1 ″ when applied will be described.

  As shown in FIG. 11, the battery system 1 ″ according to the present embodiment includes a battery module 30 having ten subassemblies 20a to 20j, an acceleration sensor 40 that detects acceleration applied to the battery module 30, An engine 80 as a power source, a muffler 81 connected to the engine 80 via an exhaust manifold or an exhaust pipe (not shown), and an opening / closing valve for opening and closing a communication path between the muffler 81 and the battery module 30 82, and a controller 60 that controls the number of revolutions of the engine 80 and the opening / closing of the opening / closing valve 82. The battery module 30 and the acceleration sensor 40 of the battery system 1 ″ according to this embodiment are the first embodiment. It is the same structure as what was demonstrated in the form. In FIG. 11, the flow of the exhaust gas is shown by a solid line, and the flow of the acceleration detection signal and the control command signal is shown by a one-dot chain line.

  The engine 80 is an internal combustion engine such as a gasoline engine or a diesel engine. Exhaust gas generated by the engine 80 is guided to the muffler 81 through an exhaust manifold and an exhaust pipe (not shown). The muffler 81 reduces the temperature and pressure of the exhaust gas to mute it, and exhausts it outside the vehicle.

  Furthermore, in this embodiment, a communication path is provided so that the inside of the muffler 81 and the expansion valve 36 of the battery module 30 communicate with each other, and an open / close valve 82 is provided so as to be able to open and close the communication path. .

  Hereinafter, an expansion operation process of the battery system 1 ″ according to the present embodiment when a large acceleration is applied, for example, when the hybrid electric vehicle suddenly stops will be described with reference to FIG.

  As a precondition, when the hybrid electric vehicle is running normally, the opening / closing valve 82 is closed, and the muffler 81 and the expansion valve 36 of the battery module 30 are not in communication. Similarly to the first embodiment, the expansion valve 36 in the initial state is set to communicate with each expansion rubber 38 via the gas injection tube 37, and communicates with the inside of the housing 31. Absent.

  For example, when a large acceleration is applied due to, for example, a sudden stop of the hybrid electric vehicle, first, the acceleration sensor 40 detects the acceleration in step S210 of FIG.

  The detection result is sent to the controller 60 by the acceleration sensor 40. The controller 60 performs control to open the opening / closing valve 82 based on the detection result (step S220). As a method for determining the opening / closing of the opening / closing valve 82 in the controller 60, for example, a method of comparing the detection result with a predetermined threshold can be cited as in the first embodiment.

  The opening operation of the opening / closing valve 82 causes the muffler 81 and the battery module 30 to communicate with each other, and exhaust gas is supplied from the engine 80 to the expansion valve 36 of the battery module 30 via the muffler 81 (step S230). At this time, the controller 60 may control the engine 80 to increase the rotational speed, thereby increasing the pressure of the exhaust gas supplied to the battery module 30.

  The exhaust gas supplied to the expansion valve 36 of the battery module 30 is further supplied to each expansion rubber 38 via the gas injection tube 37 in the battery module 30, thereby increasing the internal pressure of each expansion rubber 38. Then, expansion is started (step S240).

  When each expansion rubber 38 is expanded by the exhaust gas supplied as described above, each space S surrounded by each bus bar 21 and the different polarity terminals 104 and 105 in the battery module 30 is expanded. Here, since the joint portion between the electrode terminals 104 and 105 and the bus bar 21 has a structure that is weak against external force, the joint portion is easily peeled off by the expansion of the space S due to the expansion of the expansion rubber 38, and the electrode terminal. 104 and 105 and the bus bar 21 are electrically disconnected (step S250).

  As described above, in the battery system 1 ″ according to the present embodiment, the expansion rubber 38 is expanded using the exhaust gas exhausted from the engine 80 via the muffler 81 as the expansion fluid. By extending the space S, the joint between the electrode terminals 104 and 105 of the thin battery 10 and the bus bar 21 is peeled off, whereby the series connection in the battery module is short-circuited and the thin batteries are separated from each other. It is possible.

  When the joint between the electrode terminals 104 and 105 and the bus bar 21 is peeled off (when a sufficient amount of exhaust gas is supplied to peel off the joint), the controller 60 supplies the exhaust gas to the gas injection tube 37. A control command is sent to the expansion valve 36 so as to switch from the inside to the inside of the casing 31. The expansion valve 36 switches the valve in accordance with this control command and supplies exhaust gas into the housing 31. At this time, since the open / close valve 82 is opened so that the exhaust gas is supplied from the engine 80 via the muffler 81 in step S220, the internal pressure of the housing 31 rises and the bellows 32 extends in a predetermined direction. Then, the casing 31 expands (S260). In particular, in step S230, when the controller 60 controls the engine 80 to increase the rotational speed, the internal pressure of the housing 31 can be increased more quickly.

  Thus, in the battery system 1 ″ according to the present embodiment, the exhaust gas exhausted from the engine 80 via the muffler 81 is used as an expansion fluid to increase the internal pressure of the casing 31 and extend the bellows 32. Thus, the casing 31 is expanded, and the applied acceleration can be absorbed by the casing 31 thus expanded, so that the battery module 30 can be more effectively prevented from entering the vehicle interior. It becomes.

  The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

FIG. 1 is an overall plan view of a thin battery according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a partially exploded perspective view showing the battery module in the embodiment of the present invention. FIG. 4 is a schematic cross-sectional view of the battery module in the embodiment of the present invention. FIG. 5 is a perspective view showing an appearance of the battery module in the embodiment of the present invention. FIG. 6 is a block diagram showing the overall configuration of the battery system according to the first embodiment of the present invention. FIG. 7 is a schematic diagram showing an electric vehicle equipped with the battery system according to the first embodiment of the present invention. FIG. 8 is a flowchart showing an expansion operation process in the battery system according to the first embodiment of the present invention. FIG. 9 is a block diagram showing the overall configuration of the battery system according to the second embodiment of the present invention. FIG. 10 is a flowchart showing an expansion operation process in the battery system according to the second embodiment of the present invention. FIG. 11 is a block diagram showing the overall configuration of the battery system according to the third embodiment of the present invention. FIG. 12 is a flowchart showing an expansion operation process in the battery system according to the third embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Battery system 10 ... Thin battery 101 ... Positive electrode plate 101a ... Positive electrode side collector 101b, 101c ... Positive electrode layer 102 ... Separator 103 ... Negative electrode plate 103a ... Negative electrode side collector 103b, 103c ... Negative electrode layer 104 ... Positive electrode terminal 105 ... Negative electrode terminal 106 ... Upper battery exterior 107 ... Lower battery exterior 20 ... Subassembly 21 ... Bus bar 30 ... Battery module 31 ... Housing 32 ... Bellows 33, 34 ... External terminal 35 ... Cooling duct 36 ... Expansion valve 37 ... Gas injection Tube 38 ... Expanded rubber 40 ... Acceleration sensor 50 ... Cooling device 51 ... Cooling device power supply 52 ... Main valve 60 ... Controller 70 ... Fuel cell 71 ... Hydrogen tank 72 ... Compressor motor 73, 74 ... Hydrogen valve 75, 76 ... Air Valve 80 ... engine 81 ... muffler 82 ... open / close valve C ... Electric vehicle M ... Drive motor S ... Space

Claims (6)

A plurality of thin batteries in which a positive electrode terminal and a negative electrode terminal are led out from the outer periphery of the battery exterior are arranged side by side, and one of the positive terminals of each of the thin batteries is connected in parallel electrically by a pair of bus bars. A battery module in which a plurality of subassemblies consisting of these thin batteries and bus bar pairs are stacked and electrically connected in series, and the plurality of subassemblies are housed in an airtight state inside the housing;
Acceleration detecting means for detecting an acceleration applied to an object on which the battery module is mounted;
An expansion means that is expandable by a fluid, and expands a predetermined portion of the battery module;
Fluid supply means for supplying fluid to the expansion means;
And a control unit that controls the fluid supply unit based on a detection result of the acceleration detection unit. The expansion means includes an expansion member that expands a space surrounded by electrode terminals of the thin battery stacked on each other and a bus bar joined to the electrode terminals,
The battery system according to claim 1, wherein the control unit controls the fluid supply unit to supply a fluid to the inside of the expansion member based on a detection result of the acceleration detection unit. The expansion means includes a bellows portion provided in the casing so as to extend the casing in a predetermined direction,
The battery system according to claim 1, wherein the control unit controls the fluid supply unit so as to supply a fluid to the inside of the housing based on a detection result of the acceleration detection unit. The fluid supply means includes
Cooling means for cooling the battery module;
The supply destination of the fluid of the cooling means includes a cooling channel for cooling the battery module or a valve that can be switched to either the expansion means. Battery system. The fluid supply means includes
Hydrogen supply means for supplying hydrogen to the fuel cell;
A hydrogen valve capable of switching the hydrogen supply destination of the hydrogen supply means to either the fuel cell or the expansion means;
Oxygen supply means for supplying oxygen to the fuel cell;
The battery system according to any one of claims 1 to 3, further comprising an air valve capable of switching an oxygen supply destination of the oxygen supply means to either the fuel cell or the expansion means. The fluid supply means includes
An internal combustion engine;
A battery system according to any one of claims 1 to 3, further comprising a valve capable of supplying exhaust gas exhausted from the internal combustion engine to the expansion means.

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