Mobile body

Abstract

To strike a balance between usual ventilation property and safety after extinction on a battery.SOLUTION: A mobile body includes: a battery; a storage part including a vent hole and storing the battery; and a blocking means for blocking the vent hole when the temperature exceeds a predetermined temperature.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a moving object. [Background technology]

[0002] Once a battery installed in a mobile vehicle catches fire, it continues to retain heat even after the fire is extinguished, and there is a risk of re-ignition. If re-ignition cannot be prevented, it is difficult to safely retrieve the battery after the fire is extinguished. To prevent re-ignition, it is necessary to keep the battery at a low temperature or discharge it by submerging it in water, etc.

[0003] For example, in the technology described in Patent Document 1, when the temperature of a battery (battery module) reaches a predetermined value (e.g., 100°C), a liquid such as water is supplied into the storage compartment in which the battery is housed, causing the battery to become submerged (submerged in liquid). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-122031 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the technology described in Patent Document 1, since the battery is enclosed in the housing, it is difficult to ensure ventilation of the battery under normal conditions. In particular, batteries installed in aircraft such as multicopters require good ventilation to easily dissipate heat. The present invention has been made in consideration of the above circumstances, and has an object to achieve both normal breathability and safety after a fire has been extinguished in a battery. [Means for solving the problem]

[0006] In order to achieve the above object, one embodiment of the present invention is a moving body, A battery; a housing portion having an air vent and housing the battery; a closing means for closing the ventilation hole when a predetermined temperature is exceeded; Equipped with. Effect of the Invention

[0007] According to the present invention, the vent of the storage unit that stores the battery is closed by the closing means when the closing means exceeds a predetermined temperature. This ensures ventilation to the battery through the vent under normal circumstances. In addition, when a fire breaks out or after the fire has been extinguished, a discharge liquid such as water can be stored in the storage unit with the vent closed to submerge the battery. This allows both normal ventilation of the battery and safety after the fire has been extinguished. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of an unmanned aerial vehicle according to an embodiment; [Diagram 2] 2 is a cross-sectional view of the battery unit according to the embodiment. FIG. [Diagram 3] 4 is a cross-sectional view showing a state of the battery unit in a normal state. FIG. [Figure 4] 1 is a cross-sectional view showing a state of a battery unit when it catches fire. FIG. [Diagram 5] 11 is a cross-sectional view showing the state of the battery unit after the fire has been extinguished. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] [Overall configuration of unmanned aerial vehicle] FIG. 1 is a perspective view of an unmanned aerial vehicle 1 according to this embodiment. As shown in Figure 1, the unmanned aerial vehicle (hereinafter simply referred to as "unmanned aircraft") 1 of this embodiment is an example of a moving body according to the present invention, and is a multicopter that obtains lift (thrust) by means of multiple rotating wing sections (propellers) 21.

[0011] Specifically, the drone 1 comprises a main body section 20 and a plurality of rotor sections 21. The multiple rotary blade portions 21 are provided at the tips of multiple arm portions 22 extending from the main body portion 20 in all four directions. The main body 20 is formed in a rectangular box shape, and includes a battery unit 5 (see FIG. 2) that supplies power to each part of the drone 1.

[0012] [Battery unit configuration] FIG. 2 is a cross-sectional view of the battery unit 5. As shown in FIG. As shown in FIG. 2, the battery unit 5 includes a battery case 52 that houses at least one battery cell 51 (two in this embodiment).

[0013] The battery case 52 is formed, for example, in the shape of a rectangular box. A first ventilation hole 52a that communicates between the inside and the outside of the battery case 52 is formed in the side plate and the bottom plate (lower plate) of the battery case 52. However, as long as the first ventilation hole 52a is formed in at least one (one location) of the side plate and the bottom plate of the battery case 52, the position, shape, number, etc. of the first ventilation hole 52a are not particularly limited. A plurality of slit holes 52b, which are slit-shaped holes, are formed in the upper plate of the battery case 52. As described later, the slit holes 52b are through holes for injecting a discharge treatment liquid such as a fire extinguishing agent 65 described later or water into the inside of the case when the battery cell 51 catches fire. In this embodiment, the slit holes 52b are formed directly above the battery cell 51.

[0014] A cooling fan 54 and a first cooling water pipe 55 for cooling the battery cells 51 are arranged inside the battery case 52. The cooling fan 54 is disposed, for example, to the side of the battery cell 51, and ventilates the inside of the battery case 52 when driven. The first cooling water pipe 55 is routed inside the battery case 52 so as to extend, for example, along the battery cells 51, and both ends are connected to an external cooling water pump (not shown). When the cooling water pump is driven, cooling water circulates through the first cooling water pipe 55, and the inside of the battery case 52 is cooled.

[0015] The battery case 52 is detachably housed in the battery mounting shelf 61. For example, the battery case 52 can be detached from the battery mounting shelf 61 by inserting and removing it in a direction perpendicular to the plane of the paper in FIG. The battery mounting shelf 61 is formed in a shape that opens upward, and is attached to the underside of the aircraft body 23, with the aircraft body 23 that closes the opening serving as a top plate. The aircraft body 23 is a part of the main body 20 of the drone 1. The battery mounting shelf 61 is formed in a shape that at least in a plan view substantially corresponds to the battery case 52, and houses the battery case 52 with almost no gap between the battery mounting shelf 61 and the side plates and bottom plate of the battery case 52.

[0016] Second ventilation openings 61a corresponding to the first ventilation openings 52a of the battery case 52 are formed in the side plates and bottom plate of the battery mounting shelf 61. The second ventilation openings 61a, together with the first ventilation openings 52a at a corresponding position, communicate between the inside of the battery case 52 and the outside of the battery mounting shelf 61. Note that the position, shape, quantity, etc. of the second ventilation openings 61a are not particularly limited as long as they are formed in at least one (one location) of the side plates and bottom plate of the battery mounting shelf 61 corresponding to the first ventilation openings 52a.

[0017] Each second ventilation opening 61a is provided with a blocking means 62 capable of blocking the second ventilation opening 61a. When a predetermined temperature is exceeded, the blocking means 62 automatically blocks the second ventilation opening 61a without relying on external electrical control. For example, a thermally expandable fireproof material can be used for the blocking means 62. The thermally expandable fireproof material is a fireproof material that expands several to several tens of times at a predetermined temperature, and is used, for example, for fire prevention measures and fire spread prevention in buildings. As the blocking means 62, such a thermally expandable fireproof material may be disposed around the periphery of the second vent 61a so as to block the second vent 61a as it expands. The specific configuration of the blocking means 62 is not particularly limited as long as it blocks the second ventilation opening 61a when the temperature exceeds a predetermined temperature. For example, the blocking means 62 may be a fireproof shutter that blocks the second ventilation opening 61a, which is biased with a metal wire that burns off at a predetermined temperature. When the blocking means 62 blocks the second ventilation opening 61a, it is preferable that the blocking means 62 can completely seal the second ventilation opening 61a so that air does not leak, but it is sufficient if a sealed state that does not cause a large amount of water (liquid) leakage is obtained.

[0018] The internal space S1 of the battery mounting shelf 61 (more precisely, the space defined by the battery mounting shelf 61 and the aircraft body 23) has a space (surplus space) above the battery case 52. A second cooling water pipe 64 and a fire extinguishing agent 65 are provided in the space within this internal space S1. The second cooling water pipe 64 is attached to a side plate of the battery mounting shelf 61, for example, in the vicinity of the battery case 52, and both ends are connected to an external cooling water pump (not shown). By driving the cooling water pump, cooling water circulates through the second cooling water pipe 64, cooling the battery case 52. The second cooling water pipe 64 may be the same cooling system as the first cooling water pipe 55, or may be a different cooling system. The extinguishing agent 65 is disposed above the battery case 52 and fixed to the underside of the aircraft body 23. The extinguishing agent 65 is enclosed so as to drop into the battery case 52 below when the ambient temperature in the internal space S1 exceeds a predetermined temperature. The "predetermined temperature" is the temperature in the internal space S1 at which the battery cell 51 is considered to have ignited. The extinguishing agent 65 is preferably disposed at least above the slit hole 52b. However, it is sufficient that the extinguishing agent 65 is provided so as to automatically apply to the battery cell 51 without relying on external control when the predetermined temperature is exceeded.

[0019] In addition, a pressure regulating valve 66 and a liquid supply port 67 are provided in the internal space S1 of the battery mounting shelf 61. The pressure regulating valve 66 is disposed in the aircraft body 23 to allow communication between the internal space S1 and the outside, and is closed in a normal state (normal state). When a predetermined temperature is reached (or when manually operated), the pressure regulating valve 66 allows communication between the internal space S1 and the outside. The liquid supply port 67 is disposed in the machine body 23 to allow communication between the internal space S1 and the outside, and is normally closed. The outside side of the liquid supply port 67 (the upper side in the figure) is a socket to which, for example, a liquid supply hose or the like can be attached. By attaching a liquid supply hose or the like to the outside side of the liquid supply port 67, liquid for discharge treatment can be supplied from the outside into the internal space S1.

[0020] The battery mounting shelf 61 is covered by a battery cover 71 . The battery cover 71 is exposed to the outside of the drone 1. Specifically, the battery cover 71 is formed in a shape that opens upward, and is attached to the underside of the aircraft body 23 so that the opening is closed by the aircraft body 23. The battery cover 71 is disposed so as to surround the entire underside of the battery mounting shelf 61, including the sides thereof, with a predetermined ventilation space S2 interposed between the battery cover 71 and the battery mounting shelf 61. Mesh-like ventilation holes 71a that communicate between the outside of the drone 1 and the ventilation space S2 are formed on the side plate of the battery cover 71. Note that the position, shape, number, etc. of the ventilation holes 71a are not particularly limited as long as they are provided to communicate between the outside and the ventilation space S2.

[0021] [Battery unit functions and operations] Next, the function and operation of the battery unit 5 will be described. 3 to 5 are cross-sectional views showing the states of the battery unit 5, with FIG. 3 being in a normal state, FIG. 4 being at the time of ignition, and FIG. 5 being after the fire has been extinguished. "Normal times" refers to times other than emergencies, including when a fire breaks out and after the fire has been extinguished.

[0022] <Normal time> Under normal circumstances (for example, when the drone 1 is flying), the battery unit 5 supplies the necessary power to each part of the drone 1 by generating power from the battery cells 51. At this time, the battery cells 51 are air-cooled by the cooling fan 54 that ventilates the inside of the battery case 52, as shown in Fig. 3. Specifically, first, the outside air of the drone 1 flows into the ventilation space S2 in the battery cover 71, for example, through the ventilation hole 71a on the front side of the drone 1. The air in the ventilation space S2 flows into the battery case 52, for example, through the first ventilation port 52a and the second ventilation port 61a on the lower side, and cools the battery cells 51, and then flows out again into the ventilation space S2 from the first ventilation port 52a and the second ventilation port 61a on the side. The air that flows out from inside the battery case 52 into the ventilation space S2 flows out to the outside of the drone 1, for example, through the ventilation hole 71a on the rear side of the drone 1. In this way, the battery unit 5 has a structure with good ventilation, and heat from the battery cells 51 is preferably removed under normal circumstances.

[0023] At this time, the battery case 52 is water-cooled (liquid-cooled) by the cooling water passed (liquid-passed) through the first cooling water pipe 55 and the second cooling water pipe 64. Specifically, a cooling water pump (not shown) circulates the cooling water through the first cooling water pipe 55 inside the battery case 52 and the second cooling water pipe 64 outside the battery case 52. The first cooling water pipe 55 directly cools the battery cells 51, and the second cooling water pipe 64 indirectly cools the battery cells 51 from outside the battery case 52.

[0024] <When ignited> If the battery cell 51 catches fire for some reason, the battery unit 5 performs a fire extinguishing operation. Specifically, as shown in Fig. 4, first, the blocking means 62 blocks the second ventilation opening 61a of the battery mounting shelf 61 to isolate the source of fire from the outside air. The blocking means 62 in this embodiment is a thermally expandable fire-resistant material, and when the battery cell 51 ignites, the temperature rises to a predetermined temperature and expands to block the second ventilation opening 61a. This makes it possible to suppress the spread of the fire.

[0025] In addition, the fire extinguishing agent 65 arranged above the battery case 52 melts and drops due to the rise in the ambient temperature caused by the ignition of the battery cell 51. This fire extinguishing agent 65 drops to the battery case 52 below and falls onto the battery cells 51 inside the battery case 52 through the slit holes 52b, extinguishing the fire.

[0026] Also, a valve may be provided in the second cooling water pipe 64, and the cooling water in the second cooling water pipe 64 may be discharged (discharged) by opening the valve manually or automatically (automatically according to temperature). The valve may be replaced with a configuration that allows the cooling water in the second cooling water pipe 64 to be discharged to the outside manually or automatically. For example, a part of the second cooling water pipe 64 may be provided with a heat-sensitive portion that automatically leaks the cooling water therein at a predetermined temperature. Furthermore, the first cooling water pipe 55 may also be provided with a similar configuration that allows the cooling water inside to be discharged to the outside manually or automatically. As a result, the cooling water can be discharged (discharged) into the internal space S1 of the battery mounting shelf 61 to extinguish the fire in the battery cells 51.

[0027] <After extinguishing> As described above, the fire in the battery cell 51 is extinguished by dropping the fire extinguishing agent 65 or further by spraying (discharging) cooling water. In this case, when cooling water is discharged (discharged) into the internal space S1 of the battery mounting shelf 61 during fire extinguishing (ignition), the internal space S1 is filled with cooling water because the second ventilation opening 61a of the battery mounting shelf 61 is blocked by the blocking means 62, as shown in FIG. 5. If the amount of water (liquid) in the internal space S1 is insufficient (for example, the battery case 52 is not completely submerged in water (liquid)), or if cooling water is not discharged (discharged) during fire extinguishing in the first place, further cooling water can be discharged (discharged), or liquid for discharge processing can be supplied from the outside into the internal space S1 through the liquid supply port 67. This allows the battery cells 51 to be submerged in water (liquid immersion) together with the battery case 52. Therefore, the battery cells 51 can be cooled and discharged with a sufficient amount of water (liquid).

[0028] The liquid for discharge treatment supplied into the internal space S1 is not particularly limited as long as it accelerates the discharge of the battery cell 51. The liquid is, for example, a sodium chloride aqueous solution of a predetermined concentration, water, an anionic surfactant described in Japanese Patent No. 6847716, an aqueous solution of an alkali metal weak acid salt described in Japanese Patent Laid-Open No. 2005-347162, or the like. Furthermore, when supplying the liquid, the pressure regulating valve 66 may be opened to release the air (including the generated gas) in the internal space S1 to the outside. The opening of this pressure regulating valve 66 may be performed manually or automatically when ignition occurs.

[0029] [Technical effect of the present embodiment] As described above, according to this embodiment, the second ventilation opening 61a of the battery mounting shelf 61 that houses the battery case 52 (battery cell 51) is closed by the closing means 62 when the closing means 62 exceeds a predetermined temperature. Therefore, ventilation to the battery case 52 (battery cells 51) through the second ventilation opening 61a can be ensured under normal circumstances. In addition, when a fire breaks out or after the fire has been extinguished, liquid for discharge processing can be stored in the internal space S1 of the battery mounting shelf 61 with the second ventilation opening 61a blocked, and the battery case 52 can be submerged in water (liquid submersion). This allows the battery cells 51 to be appropriately discharged, and the risk of re-ignition or electric shock can be suppressed, allowing the battery case 52 to be safely collected. Therefore, it is possible to achieve both normal breathability in the battery and safety after the fire has been extinguished.

[0030] Further, according to this embodiment, the internal space S1 of the battery mounting shelf 61 is provided with liquid supply means (at least one of the first cooling water pipe 55, the second cooling water pipe 64, and the liquid supply port 67) capable of supplying liquid for discharge treatment. This allows the liquid for discharge treatment to be quickly supplied to the internal space S1 when a fire breaks out or after the fire has been extinguished, and the battery cells 51 can be suitably extinguished or submerged in water (liquid submersion).

[0031] Furthermore, according to this embodiment, the blocking means 62 is a heat-expandable fire-resistant material that expands at a predetermined temperature, and is disposed around the periphery of the second vent 61a to block the second vent 61a when expanded. This makes it possible to suitably close the second ventilation opening 61a at a predetermined temperature with a simple configuration and an automatic operation that does not require electrical control.

[0032] Furthermore, according to this embodiment, the extinguishing agent 65 that drops at a predetermined temperature is disposed above the battery case 52 in the internal space S1 of the battery mounting shelf 61. This makes it possible to suitably extinguish a fire in the battery case 52 (battery cell 51) in the event of a fire, with a simple configuration and an automatic operation that does not require electrical control.

[0033] Furthermore, according to this embodiment, the battery mounting shelf 61 detachably houses the battery case 52 in which the battery cells 51 are housed. This allows a plurality of battery cells 51 and the like to be modularized (unitized), making it possible to easily handle the module, including recovery after extinguishing a fire.

[0034] [others] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments (including modified examples). For example, in the above embodiment, the fire in the battery cell 51 is extinguished by the fire extinguishing agent 65 and the cooling water. However, the fire may be extinguished only by the fire extinguishing agent 65 without using the cooling water. In this case, the first cooling water pipe 55 and the second cooling water pipe 64 are not necessary. The liquid used in the cooling system of the battery cells 51 is water (cooling water) or a liquid containing an additive such as an antifreeze agent.

[0035] In the above embodiment, the second ventilation opening 61a of the battery mounting shelf 61 is closed by the closing means 62, and the liquid for discharging treatment is supplied to the internal space S1 of the battery mounting shelf 61. However, a closing means may be disposed in the first ventilation opening 52a of the battery case 52, and in the event of ignition, the first ventilation opening 52a may be closed by the closing means, and liquid may be supplied into the battery case 52. With such a configuration, the battery cells 51 can also be submerged in water (liquid submerged).

[0036] In the above embodiment, an unmanned aerial vehicle has been described as an example of a moving body according to the present invention. However, the present invention can be widely applied to moving bodies equipped with a battery (for example, vehicles, ships, toys imitating these, etc.). However, the moving body according to the present invention can be more suitably applied to aircraft, which have a strong demand for breathability and lightweight batteries under normal conditions, than automobiles (electric vehicles) and the like, in which the batteries are sealed in a robust housing.

[0037] In addition, the details shown in the above embodiment can be modified as appropriate without departing from the spirit of the invention. [Explanation of symbols]

[0038] 1 Unmanned aerial vehicle (mobile) 5 Battery Unit 23 Aircraft body 51 Battery Cell 52 Battery case (case material) 52a First Vent 52b Slit hole 54 Cooling fan 55 1st cooling water piping (liquid supply means) 61 Battery mounting shelf (storage section) 61a Second Vent (Vent) 62 Obstruction means 64 2nd cooling water piping (liquid supply means) 65 Fire extinguishing agents 66 Pressure Regulating Valve 67 Liquid supply port (liquid supply means) 71 Battery cover 71a Ventilation hole S1 interior space S2 Ventilation space

Claims

1. A battery; a housing portion having an air vent and housing the battery; a closing means for closing the ventilation hole when a predetermined temperature is exceeded; A mobile body comprising:

2. A liquid supply means capable of supplying a liquid for discharge treatment into the storage unit is provided. The moving body according to claim 1 .

3. The blocking means is a heat expandable fire-resistant material that expands at a predetermined temperature, and is disposed around the periphery of the vent hole to block the vent hole when expanded. The moving body according to claim 1 .

4. A fire extinguishing agent that falls at a predetermined temperature is disposed above the battery in the storage section. The moving body according to claim 1 .

5. the battery is a battery cell housed in a case member, The housing portion detachably houses the case member. The moving body according to claim 1 .

Images