Pressure release mechanism

Abstract

To provide a technique which can smoothly release a pressure in a battery case while protecting an on-off valve.SOLUTION: A pressure release mechanism may include: an on-off valve which opens or closes a gas discharge port; and a cover member which covers the on-off valve. A cover state in which the cover member covers the on-off valve may be released by valve opening operation of the on-off valve.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology disclosed herein relates to pressure relief mechanisms. [Background technology]

[0002] Patent Document 1 discloses a pressure release valve for a battery pack that is attached to an opening formed in a pack case of a battery pack. The pressure release valve for a battery pack in Patent Document 1 includes a case having a vent hole that communicates with the opening of the pack case and a valve mechanism capable of opening and closing the vent hole, and a cover that, when attached to the case, forms a passage between the cover and the case for discharging gas discharged from the vent hole. The valve mechanism includes a valve member that can close the vent hole, and a biasing portion that biases the valve member to a closed position that closes the vent hole. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-194719 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the pressure relief valve of Patent Document 1, gas discharged from the exhaust hole passes through a passage between the case and the cover and is discharged to the outside, which creates a problem in that the airflow resistance increases when the pressure is released, making it impossible to smoothly release the pressure inside the pack case.

[0005] The present specification provides a technique that can smoothly release the pressure inside the battery case while protecting the on-off valve. [Means for solving the problem]

[0006] A first aspect of the present technology relates to a pressure release mechanism attached to a gas exhaust port of a battery case in order to release pressure inside the battery case. The pressure release mechanism may include an on-off valve that opens and closes the gas exhaust port, and a covering member that covers the on-off valve. An opening operation of the on-off valve may release a covering state in which the covering member covers the on-off valve.

[0007] According to this configuration, the on-off valve can be protected by the covering member. In addition, the covering state is released by the opening operation of the on-off valve, so that the gas inside the battery case that is discharged from the gas exhaust port when the valve is opened can be smoothly discharged to the outside. Therefore, the pressure inside the battery case can be smoothly released while protecting the on-off valve.

[0008] In a second aspect, in the first aspect, the covering state may be released by breaking the covering member by opening the on-off valve. With this configuration, the pressure inside the battery case can be smoothly released with a simple configuration.

[0009] In a third aspect, in the first aspect, the covering member may include an engagement portion that engages with another member to maintain the covered state. The covered state may be released by disengaging the engagement portion through an opening operation of the on-off valve. With this configuration, the pressure inside the battery case can be released smoothly with a simple configuration. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing a schematic diagram of a battery pack equipped with a pressure release mechanism of a first embodiment. [Diagram 2] FIG. 2 is a diagram showing a battery pack including a pressure release mechanism according to the first embodiment (showing an open / close valve in an open state). [Diagram 3] FIG. 13 is a schematic diagram showing a battery pack equipped with a pressure release mechanism according to a second embodiment. [Figure 4]FIG. 13 is a diagram showing a battery pack including a pressure release mechanism according to a second embodiment (showing an on-off valve in an open state). [Diagram 5] FIG. 13 is a diagram showing a battery pack including a modified pressure release mechanism. [Figure 6] FIG. 13 is a diagram showing a battery pack including a modified pressure release mechanism. [Figure 7] FIG. 13 is a schematic diagram showing a battery pack including a pressure release mechanism according to a modified example (showing the on-off valve in an open state). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] (First embodiment) A battery pack 100 of the first embodiment will be described with reference to the drawings. As shown in Fig. 1, the battery pack 100 of the first embodiment includes a battery case 10 and a pressure release mechanism 2 attached to the battery case 10.

[0012] The battery case 10 is made of, for example, metal or resin. The battery case 10 houses a battery 90, such as a lithium ion battery or a nickel metal hydride battery. The type of the battery 90 is not particularly limited. The battery case 10 includes an upper surface member 12 and a gas exhaust port 14 provided in the upper surface member 12. In this battery pack 100, gas inside the battery case 10 can be exhausted to the outside of the battery case 10 through the gas exhaust port 14. The position where the gas exhaust port 14 is formed is not particularly limited. For example, the gas exhaust port 14 may be provided in a side surface member 19 of the battery case 10.

[0013] The pressure release mechanism 2 will be described. The pressure release mechanism 2 includes an on-off valve 30 that opens and closes the gas discharge port 14 of the battery case 10, and a covering member 20 that covers the on-off valve 30. The on-off valve 30 includes a valve body 32 that opens and closes the gas discharge port 14, and a hinge member 34 connected to the valve body 32. The valve body 32 seals the gas discharge port 14 when the on-off valve 30 is in a closed state. The valve body 32 abuts against the upper surface member 12 of the battery case 10 when the valve is closed. The upper surface member 12 functions as a valve seat for the on-off valve 30.

[0014] The valve body 32 includes a main body 32a and a sealing member 32b fixed to the main body 32a. The sealing member 32b is fixed to the surface of the main body 32a facing the battery case 10. The sealing member 32b seals the gas discharge port 14 when the on-off valve 30 is in a closed state.

[0015] The hinge member 34 of the on-off valve 30 is configured to be rotatable relative to the battery case 10. The hinge member 34 is connected to the main body 32a of the valve body 32 and the top member 12 of the battery case 10. The hinge member 34 rotates the valve body 32 relative to the battery case 10. The rotation of the hinge member 34 opens or closes the on-off valve 30. The on-off valve 30 opens, for example, when the pressure inside the battery case 10 becomes equal to or higher than a predetermined threshold pressure. When the pressure inside the battery case 10 is lower than the threshold pressure, the on-off valve 30 does not open.

[0016] Next, the covering member 20 will be described. The covering member 20 is, for example, a waterproof filter or a waterproof film. An example of a waterproof filter is a fluororesin porous film (for example, TEMISH (registered trademark) manufactured by Nitto Denko Corporation). The covering member 20 is disposed so as to cover the entire on-off valve 30. An outer peripheral end 22 of the covering member 20 is fixed to the upper surface member 12 of the battery case 10. The outer peripheral end 22 of the covering member 20 is bonded to the upper surface member 12 of the battery case 10 by, for example, an adhesive. The covering member 20 prevents the on-off valve 30 from getting wet. In addition, the covering member 20 prevents dust from adhering to the on-off valve 30.

[0017] Next, the operation of the pressure release mechanism 2 will be described. In the above pressure release mechanism 2, when the pressure inside the battery case 10 becomes equal to or higher than a threshold pressure, the on-off valve 30 opens (see FIG. 2). When the on-off valve 30 opens, gas inside the battery case 10 is discharged from the gas discharge port 14 to the outside of the battery case 10.

[0018] Furthermore, in the pressure release mechanism 2, when the on-off valve 30 opens, the covering member 20 covering the on-off valve 30 breaks. The opening operation of the on-off valve 30 presses the covering member 20, causing the covering member 20 to break. When the covering member 20 breaks, the gas inside the battery case 10 that is discharged from the gas discharge port 14 is discharged to the outside of the covering member 20 through the broken portion of the covering member 20. This releases the pressure inside the battery case 10.

[0019] (effect) The first embodiment has been described above. As described above, the pressure release mechanism 2 of the first embodiment includes the on-off valve 30 that opens and closes the gas discharge port 14, and the covering member 20 that covers the on-off valve 30. The opening operation of the on-off valve 30 releases the covering state in which the covering member 20 covers the on-off valve 30. In the first embodiment, the opening operation of the on-off valve 30 breaks the covering member 20, releasing the covering state.

[0020] According to this configuration, the on-off valve 30 can be protected by the covering member 20. In addition, since the covered state is released by the opening operation of the on-off valve 30, the gas inside the battery case 10 that is discharged from the gas exhaust port 14 when the valve is opened can be smoothly discharged to the outside. Therefore, the pressure inside the battery case 10 can be smoothly released while protecting the on-off valve 30. The pressure inside the battery case 10 can be smoothly released with a simple configuration.

[0021] Although the first embodiment has been described above, the specific aspects are not limited to the above embodiment. In the following description, detailed description of the same configuration as in the above description may be omitted.

[0022] (Second Example) In the above-described first embodiment, the covering member 20 is broken by the valve opening operation of the on-off valve 30, but in the second embodiment, the covering member 20 may be configured not to break. In the second embodiment, the covering member 20 has a first engagement portion 25 as shown in FIG. 3. The first engagement portion 25 is provided on the outer circumferential end portion of the covering member 20.

[0023] The covering member 20 of the second embodiment is made of, for example, metal or resin, and is configured in a substantially cup shape.

[0024] In the second embodiment, the top member 12 of the battery case 10 is provided with a second engagement portion 15. The second engagement portion 15 of the battery case 10 engages with a first engagement portion 25 of the covering member 20. The first engagement portion 25 and the second engagement portion 15 are, for example, configured as a snap fit. The first engagement portion 25 of the covering member 20 is inserted into the second engagement portion 15 of the battery case 10, thereby engaging the first engagement portion 25 with the second engagement portion 15. The first engagement portion 25 and the second engagement portion 15 engage with each other in a state in which the covering member 20 covers the entire on-off valve 30. The engagement of the first engagement portion 25 and the second engagement portion 15 maintains the covering state of the covering member 20.

[0025] 4, when the on-off valve 30 opens, gas inside the battery case 10 is discharged to the outside of the battery case 10 through the gas discharge port 14. In the second embodiment, when the on-off valve 30 opens, the covering member 20 is pressed by the opening operation of the on-off valve 30, and the engagement between the first engagement portion 25 of the covering member 20 and the second engagement portion 15 of the battery case 10 is released. This releases the covering state in which the covering member 20 covers the on-off valve 30.

[0026] (effect) As described above, in the second embodiment, the covering member 20 has the first engagement portion 25 that engages with the top member 12 of the battery case 10 to maintain the covered state. The engagement of the first engagement portion 25 is released by the opening operation of the on-off valve 30, thereby releasing the covered state of the covering member 20. With this simple configuration, the pressure inside the battery case 10 can be released smoothly.

[0027] (Modification) (1) In a modified example, as shown in Figures 5 and 6, the pressure release mechanism 2 may include a seat member 50. The seat member 50 is attached to the top member 12 of the battery case 10. The seat member 50 includes an outer member 52 and an insertion member 54 fixed to the outer member 52.

[0028] The outer member 52 is disposed on the top member 12 of the battery case 10. The insert member 54 is inserted into the gas exhaust port 14 of the battery case 10. A second gas exhaust port 56 is provided in the insert member 54. A seal member 58 is disposed between the insert member 54 and the top member 12 of the battery case 10. The seal member 58 provides a seal between the insert member 54 and the top member 12.

[0029] In the pressure release mechanism 2 of the modified example, when the on-off valve 30 is opened, the gas inside the battery case 10 is discharged to the outside of the battery case 10 through the second gas discharge port 56 of the seat member 50 .

[0030] (2) In a modified example, as shown in Fig. 6, the outer member 52 of the base member 50 may have a second engagement portion 15. The second engagement portion 15 of the base member 50 engages with the first engagement portion 25 of the covering member 20. The first engagement portion 25 and the second engagement portion 15 have, for example, a snap-fit ​​configuration. For example, the first engagement portion 25 of the covering member 20 is inserted into the second engagement portion 15 of the base member 50, thereby engaging the first engagement portion 25 and the second engagement portion 15. The first engagement portion 25 and the second engagement portion 15 engage with each other in a state in which the covering member 20 covers the entire on-off valve 30.

[0031] (3) In a modified example, as shown in Figures 7 and 8, the on-off valve 30 may include a connecting member 38. The connecting member 38 is a substantially rod-shaped member and includes a base end 38a and a tip end 38b.

[0032] A base end 38a of the connecting member 38 is fixed to the valve body 32 of the on-off valve 30. A tip end 38b of the connecting member 38 is inserted into the insertion hole 28 provided in the covering member 20. The tip end 38b of the connecting member 38 has a plurality of protrusions 39 that protrude toward the inner circumferential surface of the insertion hole 28. The tip end 38b of the connecting member 38 is inserted into the insertion hole 28 in a snap-fit ​​state, for example, and is fitted into the insertion hole 28. In this way, the connecting member 38 connects the valve body 32 and the covering member 20.

[0033] In this configuration, when the on-off valve 30 is opened, the covering member 20 is pressed by the opening operation of the on-off valve 30. The covering member 20 is pressed via the connecting member 38 of the on-off valve 30. As a result, the covering state of the covering member 20 is released.

[0034] Although specific examples of the present invention have been described above in detail, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives is itself technically useful. [Explanation of symbols]

[0035] 2: pressure release mechanism, 10: battery case, 12: upper surface member, 14: gas exhaust port, 15: second engagement portion, 20: covering member, 22: outer peripheral end portion, 25: first engagement portion, 28: insertion hole, 30: on-off valve, 32: valve body, 34: hinge member, 38: connecting member, 50: base member, 52: outer member, 54: insertion member, 56: second gas exhaust port, 58: sealing member, 90: battery, 100: battery pack

Claims

1. A pressure relief mechanism attached to a gas exhaust port of a battery case for relieving pressure inside the battery case, an on-off valve for opening and closing the gas exhaust port; A covering member that covers the on-off valve, a pressure release mechanism for releasing the covering member from covering the on-off valve by an opening operation of the on-off valve;

2. 2. The pressure relief mechanism of claim 1, A pressure release mechanism, characterized in that the covering member is broken by the opening operation of the on-off valve, thereby releasing the covered state.

3. 2. The pressure relief mechanism of claim 1, the covering member includes an engaging portion that engages with another member to maintain the covering state, a pressure release mechanism, characterized in that the covered state is released by disengaging the engaging portion through an opening operation of the on-off valve.

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