Battery pack

Abstract

To provide a battery pack capable of reducing carbon monoxide and hydrogen fluoride contained in gas exhausted to the outside.SOLUTION: A battery pack according to the present invention includes a battery cell, and an exhaust pipe that releases gas exhausted from the battery cell to the outside, and the inlet of the exhaust pipe is provided above the battery cell, and the outlet of the exhaust pipe is provided with a pressure control valve. A carbon monoxide reduction device and a hydrogen fluoride reduction device are arranged in order from the inlet side to the outlet side of the exhaust pipe.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a battery pack. [Background technology]

[0002] Patent Document 1 discloses a battery pack having a vent valve configured to vent internal gas to the outside when the internal pressure increases. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-197622 Summary of the Invention [Problem to be solved by the invention]

[0004] Gases discharged from battery cells housed in a battery pack contain carbon monoxide and hydrogen fluoride, so there is room for consideration on reducing the amounts of carbon monoxide and hydrogen fluoride contained in the gases discharged to the outside of the battery pack.

[0005] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a battery pack that can reduce the carbon monoxide and hydrogen fluoride contained in gas discharged to the outside. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, the battery pack of the present invention is a battery pack comprising a battery cell and an exhaust pipe that releases gas exhausted from the battery cell to the outside, wherein the inlet of the exhaust pipe is provided above the battery cell, a pressure control valve is provided at the outlet of the exhaust pipe, and a carbon monoxide reduction device and a hydrogen fluoride reduction device are arranged in this order from the inlet side to the outlet side of the exhaust pipe. [Effects of the Invention]

[0007] The battery pack according to the present invention has an effect of reducing carbon monoxide and hydrogen fluoride contained in gas discharged to the outside. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a side view showing a schematic configuration of a battery pack according to the first embodiment. [Figure 2] FIG. 2 is a side view showing a schematic configuration of a battery pack according to the second embodiment. [Figure 3] FIG. 3 is a side view showing a schematic configuration of a battery pack according to the third embodiment. [Figure 4] FIG. 4 is a side view showing a schematic configuration of a battery pack according to the fourth embodiment. [Figure 5] FIG. 5 is a top view showing a schematic configuration of a battery pack according to the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] (Embodiment 1) A battery pack according to a first embodiment of the present invention will be described below, although the present invention is not limited to this embodiment.

[0010] FIG. 1 is a side view showing a schematic configuration of a battery pack 6 according to a first embodiment. The battery pack 6 according to the first embodiment includes a battery cell 1, an exhaust pipe 2 that forms a gas exhaust path through which generated gas G1 from the battery cell 1 is exhausted to the outside, and a battery pack case 61 that houses the battery cell 1. A plurality of battery cells 1 are arranged in a predetermined direction inside the battery pack case 61 to form a battery module. The exhaust pipe 2 is connected to a top plate 611, which is the upper wall in the height direction of the battery pack case 61, and the interior of the battery pack case 61 communicates with the interior of the exhaust pipe 2 via an inlet 21 of the exhaust pipe 2. The inlet 21 of the exhaust pipe 2 is provided above the battery cell 1. An outlet 22 of the exhaust pipe 2 is provided with a pressure control valve 3 for exhausting gas that has passed through the exhaust pipe 2 to the outside. A carbon monoxide reduction device 4 and a hydrogen fluoride reduction device 5 are arranged in this order inside the exhaust pipe 2, from the inlet 21 side toward the outlet 22 side of the exhaust pipe 2.

[0011] The carbon monoxide reduction device 4 is provided with a catalyst containing a precious metal such as platinum (Pt) or palladium (Pd), for example, an oxidation catalyst used in automobile exhaust gas catalysts. This catalyst can be configured to be longer than the exhaust pipe 2, or to have a smaller lattice size, or to have a larger contact area to allow the precious metal of the catalyst to come into contact with and react with a larger amount of carbon monoxide gas. In the carbon monoxide reduction device 4, carbon monoxide contained in the gas undergoes an oxidation reaction with the catalyst, producing carbon dioxide (2CO + O → 2CO).

[0012] The hydrogen fluoride reduction device 5 is provided with a structure made of slaked lime. Note that soda lime or the like may be used instead of slaked lime. The structure is a structure through which the gas passes while coming into contact with slaked lime, and for example, a filter structure containing slaked lime as a component, a filter structure with a surface coated with slaked lime, or a catalyst structure made of slaked lime may be employed. In the hydrogen fluoride reduction device 5, the hydrogen fluoride contained in the gas reacts with the slaked lime to produce calcium fluoride and water (Ca(OH)2 + HF → CaF2 + 2H2O).

[0013] In the battery pack 6, the battery cells 1 become hot, and high-temperature generated gas G1 is discharged from the battery cells 1. The generated gas G1 fills the battery pack case 61 and flows into the exhaust pipe 2 connected to the top of the battery pack case 61. When the pressure inside the battery pack 6 rises and exceeds a predetermined threshold, the pressure control valve 3 provided at the outlet 22 of the exhaust pipe 2 opens, and the generated gas G1 flows from the battery pack case 61 into the exhaust pipe 2 due to the pressure difference. In the flow direction of the generated gas G1, which flows from the inlet 21 side to the outlet 22 side of the exhaust pipe 2, the carbon monoxide contained in the generated gas G1 reacts with a catalyst in the carbon monoxide reduction device 4 located upstream in the flow direction of the generated gas G1, generating carbon dioxide and reducing the carbon monoxide contained in the generated gas G1. Then, in the hydrogen fluoride reduction device 5 located downstream in the flow direction of the generated gas G1, the hydrogen fluoride contained in the generated gas G1 reacts with slaked lime to generate calcium fluoride and water, thereby reducing the hydrogen fluoride contained in the generated gas G1. The generated gas G1 that flows through the exhaust pipe 2 and passes through the carbon monoxide reduction device 4 and the hydrogen fluoride reduction device 5 in this manner is discharged from the exhaust pipe 2 through the pressure control valve 3 in a state containing the generated carbon dioxide, calcium fluoride, and water.

[0014] As described above, in the battery pack 6 according to the first embodiment, the carbon monoxide and hydrogen fluoride contained in the exhaust gas G2 discharged from the pressure control valve 3 to the outside of the exhaust pipe 2 can be reduced.

[0015] (Embodiment 2) A battery pack according to a second embodiment of the present invention will be described below. Note that the description of the second embodiment common to the first embodiment will be omitted as appropriate.

[0016] FIG. 2 is a side view showing a schematic configuration of a battery pack 6 according to a second embodiment. The hydrogen fluoride reduction device 5 in the battery pack 6 according to the second embodiment includes an openable and closable cylindrical storage member 51 that stores slaked lime, and a wire 52 that constitutes an opening / closing mechanism for opening and closing the storage member 51. The storage member 51 is formed, for example, of a container or a bag. The wire 52 is connected to an openable / closable portion of the storage member 51 and the pressure control valve 3. In the hydrogen fluoride reduction device 5, the pressure control valve 3 opens and pulls the wire 52, thereby opening the openable / closable portion of the storage member 51 and releasing the slaked lime stored in the storage member 51 into the exhaust pipe 2 (the hollow interior of the storage member 51). As a result, the generated gas G1 flowing in the exhaust pipe 2 (the hollow interior of the storage member 51) comes into contact with the slaked lime, and the hydrogen fluoride contained in the generated gas G1 reacts with the slaked lime to produce calcium fluoride and water, thereby reducing the hydrogen fluoride contained in the generated gas G1. The generated gas G1 that flows through the exhaust pipe 2 and passes through the carbon monoxide reduction device 4 and the hydrogen fluoride reduction device 5 in this manner is discharged from the exhaust pipe 2 through the pressure control valve 3 in a state containing the generated carbon dioxide, calcium fluoride, and water.

[0017] As described above, in the battery pack 6 according to the second embodiment, the carbon monoxide and hydrogen fluoride contained in the exhaust gas G2 discharged from the pressure control valve 3 to the outside of the exhaust pipe 2 can be reduced.

[0018] The storage member 51 may also be a container or a bag made of a material having temperature characteristics that cause it to melt at the temperature of the generated gas G1 flowing inside the exhaust pipe 2. The storage member 51 is melted by the temperature (heat) of the generated gas G1 that flows inside the exhaust pipe 2 and passes through the hydrogen fluoride reduction device 5, and the slaked lime inside the storage member 51 is released into the exhaust pipe 2.

[0019] (Embodiment 3) A battery pack according to a third embodiment of the present invention will be described below. Note that the description of the third embodiment common to the first embodiment will be omitted as appropriate.

[0020] FIG. 3 is a side view showing a schematic configuration of a battery pack 6 according to a third embodiment. In the battery pack 6 according to the third embodiment, the diameter of the portion of the exhaust pipe 2 where the hydrogen fluoride reduction device 5 is disposed is larger than the diameter of the portion of the exhaust pipe 2 where the carbon monoxide reduction device 4 is disposed. In this way, the spatial volume of the portion of the exhaust pipe 2 where the hydrogen fluoride reduction device 5 is disposed is increased, and a diffuser plate 54 is disposed on a gas exhaust path formed inside a cylindrical storage member 53 that stores slaked lime. The diffuser plate 54 has a side surface positioned in a direction intersecting the longitudinal direction of the exhaust pipe 2, for example, a direction perpendicular to the longitudinal direction of the exhaust pipe 2, and is disposed so that the generated gas G1 flowing inside the exhaust pipe 2 collides with the diffuser plate 54. As a result, the generated gas G1 flowing inside the exhaust pipe 2 (the hollow interior of the storage member 53) collides with the diffuser plate 54, thereby disturbing and diffusing the flow of the generated gas G1. Then, by releasing slaked lime from the storage member 53 into this diffused generated gas G1, the hydrogen fluoride contained in the generated gas G1 and the slaked lime can be brought into efficient contact and reaction with each other, thereby reducing the amount of hydrogen fluoride contained in the generated gas G1. The generated gas G1 that flows through the exhaust pipe 2 and passes through the carbon monoxide reduction device 4 and the hydrogen fluoride reduction device 5 in this manner is discharged from the pressure control valve 3 to the outside of the exhaust pipe 2 in a state containing the produced carbon dioxide, calcium fluoride, and water.

[0021] As described above, in the battery pack 6 according to the third embodiment, the carbon monoxide and hydrogen fluoride contained in the exhaust gas G2 discharged from the pressure control valve 3 to the outside of the exhaust pipe 2 can be reduced.

[0022] In the battery pack 6 according to the third embodiment, the storage member 53 for storing slaked lime can be a container or bag made of a material having temperature characteristics that cause it to melt at the temperature of the generated gas G1 flowing through the exhaust pipe 2.

[0023] Furthermore, in the battery pack 6 according to the third embodiment, a configuration can be adopted in which a rotating member such as a turbine is used instead of the diffusion plate 54 to disturb the flow of the generated gas G1 flowing through the portion of the exhaust pipe 2 where the hydrogen fluoride reduction device 5 is located.

[0024] (Embodiment 4) A battery pack according to a fourth embodiment of the present invention will be described below. Note that the description of the fourth embodiment common to the first embodiment will be omitted as appropriate.

[0025] FIG. 4 is a side view showing a schematic configuration of a battery pack 6 according to a fourth embodiment. FIG. 5 is a top view showing a schematic configuration of the battery pack 6 according to the fourth embodiment. In the battery pack 6 according to the fourth embodiment, a battery pack case 61 is divided into a battery cell storage section 621, which is a first space in which battery cells 1 are installed via a partition wall 7, and an exhaust pipe section 622, which is a second space forming a gas exhaust path. An inlet section 201 of the exhaust pipe section 622 is formed in the partition wall 7 above the battery cells 1 and on the upstream side of the gas exhaust path formed in the exhaust pipe section 622 so as to communicate between the battery cell storage section 621 and the exhaust pipe section 622. An outlet section 202 of the exhaust pipe section 622 is formed in the top plate section 611 of the battery pack case 61 on the downstream side of the gas exhaust path formed in the exhaust pipe section 622. A pressure control valve 3 is provided in the outlet section 202 of the exhaust pipe section 622. Furthermore, a carbon monoxide reduction device 4 and a hydrogen fluoride reduction device 5 are arranged in this order within the exhaust pipe section 622 from the inlet section 201 side toward the outlet section 202 side of the exhaust pipe section 622. The battery pack 6 according to the fourth embodiment is configured so that the generated gas G1 flowing through the gas exhaust path formed in the exhaust pipe section 622 always passes through the carbon monoxide reduction device 4 and then the hydrogen fluoride reduction device 5.

[0026] In the battery pack 6 according to the fourth embodiment, the generated gas G1, which is generated when the battery cells 1 reach a high temperature, fills the battery cell housing section 621 and the exhaust pipe section 622 inside the battery pack case 61. When the pressure inside the battery pack case 61 rises and exceeds a predetermined threshold, the pressure control valve 3 provided at the outlet section 202 of the exhaust pipe section 622 opens. This pressure difference causes the generated gas G1 to flow from the battery cell housing section 621 into the exhaust pipe section 622. Then, in the flow direction of the generated gas G1, which flows from the inlet section 201 side to the outlet section 202 side of the exhaust pipe section 622, the carbon monoxide contained in the generated gas G1 reacts with a catalyst in the carbon monoxide reduction device 4 arranged upstream, producing carbon dioxide and reducing the carbon monoxide contained in the generated gas G1. Furthermore, the hydrogen fluoride reduction device 5, which is disposed downstream in the flow direction of the generated gas G1, causes the hydrogen fluoride contained in the generated gas G1 to react with slaked lime, thereby producing calcium fluoride and water, and reducing the hydrogen fluoride contained in the generated gas G1. The generated gas G1, which flows through the exhaust pipe section 622 and passes through the carbon monoxide reduction device 4 and the hydrogen fluoride reduction device 5 in this manner, is discharged from the pressure control valve 3 to the exhaust pipe section 622 and eventually to the outside of the battery pack case 61, in a state containing the produced carbon dioxide, calcium fluoride, and water.

[0027] As described above, in the battery pack 6 according to the fourth embodiment, it is possible to reduce the carbon monoxide and hydrogen fluoride contained in the exhaust gas G2 discharged from the pressure control valve 3 to the outside of the exhaust pipe section 622 (battery pack case 61). [Explanation of symbols]

[0028] 1 battery cell 2 exhaust pipes 3 Pressure control valve 4 Carbon monoxide reduction device 5 Hydrogen fluoride reduction device 6 Battery pack 7 Bulkhead 21,201 Entrance 22,202 Exit section 61 Battery pack case 611 Top plate 621 Battery cell housing 622 Exhaust pipe section G1 Gas generated G2 exhaust gas

Claims

[Claim 1] A battery cell; an exhaust pipe for discharging gas discharged from the battery cell to the outside; A battery pack comprising: the inlet of the exhaust pipe is provided above the battery cell, a pressure control valve is provided at the outlet of the exhaust pipe; a carbon monoxide reduction device and a hydrogen fluoride reduction device are disposed in this order from the inlet side to the outlet side of the exhaust pipe; The hydrogen fluoride reduction device is an openable and closable storage member in which a material for reacting with hydrogen fluoride is stored; a wire that constitutes an opening / closing mechanism for opening and closing the storage member and is connected to the opening / closing portion of the storage member and the pressure control valve; A battery pack comprising:

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