Energy storage device

Abstract

This utility model relates to an energy storage device having a battery pack comprising at least one battery cell and an exhaust pipe for discharging gas generated inside the battery pack. The exhaust pipe connects the interior of the battery pack to the exterior of the energy storage device. The exhaust pipe has: a first exhaust path through which gas generated inside the battery pack flows; a second exhaust path through which outside air flows; and a confluence section where the first and second exhaust paths merge. The angle between the first and second exhaust paths toward the confluence section is less than 90 degrees. Using this utility model, gas generated in the battery pack can be discharged to the outside through the exhaust pipe at a reduced gas temperature.

Description

Technical Field

[0001] This utility model relates to an energy storage device. Background Technology

[0002] Japanese Patent Application Publication No. 2020-134346 discloses an anomaly detection device that detects smoke emanating from battery cells inside the casing of a battery pack.

[0003] Considering that when smoke is generated inside the battery pack casing due to smoke from the battery cells, the smoke is discharged to the outside of the casing, and the smoke discharged from the battery pack casing to the outside of the vehicle or other body housing the battery pack. However, since the smoke discharged from the battery pack casing is a high-temperature exhaust gas, if the exhaust gas is discharged to the outside of the body while maintaining a constant high temperature, the high-temperature gas may come into contact with people if people are nearby. Utility Model Content

[0004] This invention was made in view of the above circumstances, and its purpose is to provide an energy storage device that can discharge gas generated in the battery pack to the outside in a state of reduced gas temperature when the gas is discharged through the exhaust pipe.

[0005] The first technical solution of this utility model is an energy storage device, comprising a battery pack including at least one battery cell and an exhaust pipe for discharging gas generated inside the battery pack. The exhaust pipe connects the interior of the battery pack to the exterior of the energy storage device. The exhaust pipe has: a first exhaust path in which gas generated inside the battery pack flows; a second exhaust path in which external air flows; and a confluence section in which the first exhaust path and the second exhaust path merge, wherein the angle between the first exhaust path and the second exhaust path toward the confluence section is less than 90 degrees.

[0006] The second technical solution of this utility model is based on the first technical solution, wherein the exhaust pipe has: a first inlet, which is the inlet of the first exhaust path, into which gas generated inside the battery pack flows; a second inlet, which is the inlet of the second exhaust path, into which external air flows; and an outlet, which is located downstream of the confluence section, into which the gas mixed in the confluence section is discharged to the outside of the energy storage device, wherein the first exhaust path allows the gas flowing in from the first inlet to flow into the confluence section, and the second exhaust path allows the external air flowing in from the second inlet to flow into the confluence section.

[0007] The third technical solution of this utility model is that, based on the second technical solution, the first exhaust path is longer than the second exhaust path.

[0008] The fourth technical solution of this utility model is, based on the third technical solution, the first exhaust path is an airflow forming path, through the generation of the gas, the internal pressure of the battery pack is higher than the atmospheric pressure, forming the flow of the gas from the first inlet to the outlet; the second exhaust path draws in external air from the second inlet through the negative pressure generated at the confluence of the gas flowing from the first inlet to the outlet inside the first exhaust path.

[0009] The fifth technical solution of this utility model is, based on the fourth technical solution, that the second inlet has the same cross-sectional area as the outlet and opens in a direction different from the opening direction of the outlet.

[0010] This invention enables the gas generated in the battery pack to be discharged to the outside through the exhaust pipe while the gas temperature is reduced. Attached Figure Description

[0011] Figure 1 This is a schematic diagram illustrating the energy storage device in the embodiment.

[0012] Figure 2 This is a diagram used to illustrate the state of gases generated in the battery pack being discharged from the exhaust pipe.

[0013] Figure 3 It is a diagram used to illustrate the confluence.

[0014] Figure 4 This is a schematic diagram illustrating the energy storage device in a modified example.

[0015] Figure 5 This is a diagram used to illustrate the state of gas generated in the battery pack being discharged from the exhaust pipe in a modified example. Detailed Implementation

[0016] The energy storage device in the embodiments of this utility model will be described in detail below. However, this utility model is not limited to the embodiments described below.

[0017] Figure 1 This diagram schematically illustrates the energy storage device in the embodiment. The energy storage device 1 includes a battery pack 2 and an exhaust pipe 3. The energy storage device 1 is mounted on a small mobile vehicle, etc. For example, in a small mobile vehicle with a passenger capacity of about 1 to 2 people, the passenger is located near the part where the energy storage device 1 is mounted. The energy storage device 1 is configured such that when high-temperature gas is generated in the battery pack 2 due to smoke from the battery cells, the high-temperature gas does not blow onto the passenger.

[0018] Battery pack 2 is a battery pack having multiple battery cells. Battery pack 2 has a battery pack housing that accommodates the multiple battery cells. Battery pack 2 is formed such that smoke is discharged upwards from the battery pack housing. The battery cells are composed of lithium-ion batteries. Each battery cell has a smoke exhaust valve located on the upper surface of the housing. An exhaust pipe 3 is disposed above the smoke exhaust valve of the battery cell.

[0019] The exhaust pipe 3 discharges the gas generated inside the battery pack 2 to the outside of the energy storage device 1. The exhaust pipe 3 is located outside the battery pack 2 and has a flow path for the gas generated by the smoke from the battery cells to flow to the outside of the battery pack 2. For example, the exhaust pipe 3 is composed of a pipe component separate from the battery pack 2. The exhaust pipe 3 is installed on the battery pack 2 from the outside of the battery pack casing. The exhaust pipe 3 connects the inside of the battery pack 2 to the outside of the energy storage device 1.

[0020] The exhaust duct 3 has a first exhaust path 10, a second exhaust path 20, a confluence section 30, a first inlet 41, a second inlet 42, and an outlet 50. The exhaust duct 3 has two inlets including the first inlet 41 and the second inlet 42 and one outlet including the outlet 50.

[0021] The first exhaust path 10 is an exhaust path that allows gas generated inside the battery pack 2 to flow to the outside of the battery pack 2. The first exhaust path 10 forms a path from the first inlet 41 to the outlet 50. The first inlet 41 is the inlet of the first exhaust path 10, and the outlet 50 is the outlet of the first exhaust path 10. The first exhaust path 10 is a flow path that allows high-temperature gas discharged from the battery pack 2 due to smoke from the battery cells to flow to the outside of the device. The outside of the device is synonymous with the outside of the energy storage device 1.

[0022] The first inlet 41 is the inlet for gas generated inside the battery pack 2 to flow into the exhaust pipe 3. The first inlet 41 is located above the battery pack 2, opening downwards, and gas discharged from the battery pack casing of the battery pack 2 flows into the first inlet 41. Figure 2 As shown, the gas emitted from the battery pack 2 through the smoke from the battery cell flows into the exhaust pipe 3 through the first inlet 41.

[0023] Outlet 50 is an exhaust port for discharging the gas flowing in the first exhaust path 10. Outlet 50 is located below the first inlet 41 and opens towards the outside of the housing. That is, outlet 50 opens towards atmospheric pressure. Since gas flows from the side of high pressure to the side of low pressure, gas flows from the high-pressure side of the first inlet 41 towards the low-pressure side of the outlet 50 within the first exhaust path 10. Specifically, when gas is generated in the battery cell through the outlet 50 opening at atmospheric pressure, and the internal pressure of the battery pack 2 becomes higher than atmospheric pressure, the first exhaust path 10 forms a flow of gas from the first inlet 41 towards the outlet 50. The gas flowing in the first exhaust path 10 is discharged towards the outside of the housing through outlet 50.

[0024] The first exhaust path 10 includes a first flow path 11 and a second flow path 12. The first flow path 11 extends horizontally from the first inlet 41. The second flow path 12 extends vertically downward from the first flow path 11. The first flow path 11 is the upstream flow path, and the second flow path 12 is the downstream flow path. Inside the first exhaust path 10, gas flows from the first inlet 41 through the first flow path 11 and the second flow path 12 to the outlet 50. A confluence section 30 is provided midway through the second flow path 12. Figure 2 As shown, the first exhaust path 10 allows the gas F1 flowing in from the first inlet 41 to flow into the confluence section 30.

[0025] The confluence section 30 is the part where the gas F1 flowing in the first exhaust path 10 and the air F2 flowing in the second exhaust path 20 merge. For example... Figure 2 As shown, in the first exhaust path 10, only gas F1 flows upstream of the confluence section 30, while gas F3, which contains gas F1 and air F2, flows downstream of the confluence section 30.

[0026] In detail, only gas F1 flows inside the first flow path 11. The gas F1 inside the first flow path 11 flows horizontally. Only air F2 flows inside the second exhaust path 20. The air F2 inside the second exhaust path 20 flows downwards in the vertical direction. Inside the second flow path 12, only gas F1 flows upstream of the confluence section 30, while gas F3, containing both gas F1 and air F2, flows downstream of the confluence section 30. The outlet 50 is located downstream of the confluence section 30 and discharges the gas F3 mixed in the confluence section 30 to the outside of the energy storage device 1. The gas F3 inside the second flow path 12 flows downwards in the vertical direction.

[0027] The second exhaust path 20 is a confluence path that allows external air entering from the second inlet 42 to flow through. The second exhaust path 20 forms a path from the second inlet 42 to the confluence port 43. The second inlet 42 is the inlet of the second exhaust path 20, and the confluence port 43 is the outlet of the second exhaust path 20. The second inlet 42 opens upwards and serves as an external air inlet for drawing in air from the atmosphere. For example, the second inlet 42 is positioned above and forward of the confluence port 43. The second exhaust path 20 is a flow path where one end on the second inlet 42 side opens into the atmosphere, and the other end on the confluence port 43 side connects to the first exhaust path 10. Inside the second exhaust path 20, air F2 flows from the second inlet 42 toward the confluence port 43.

[0028] The confluence port 43 is a supply port for supplying air F2 flowing in the second exhaust path 20 to the first exhaust path 10. The confluence port 43 opens into the second flow path 12, connecting the second exhaust path 20 and the first exhaust path 10. Air F2 flowing inside the second exhaust path 20 flows into the interior of the first exhaust path 10 via the confluence port 43. The second exhaust path 20 functions as a supply path for supplying external air drawn in from the second inlet 42 to the confluence section 30. Figure 3 As shown, in the confluence section 30, the angle θ formed by the first exhaust path 10 and the second exhaust path 20 towards the confluence section 30 is less than 90 degrees. The angle θ formed by the direction of gas F1 flowing in the second flow path 12 and the direction of air F2 flowing from the confluence port 43 to the second flow path 12 is set to be greater than 0 degrees and less than 90 degrees. The extension direction of the first exhaust path 10 and the extension direction of the second exhaust path 20 are determined in such a way that the angle θ satisfies 0 degrees or greater and less than 90 degrees.

[0029] In the exhaust duct 3, by causing gas to flow from the first inlet 41 toward the outlet 50 inside the first exhaust path 10, a negative pressure is generated at the confluence 30. This negative pressure is used to draw in outside air from the second inlet 42 through the confluence port 43. Since the gas flows from the side with the shorter flow path to the side with the longer flow path, the first exhaust path 10 is formed to be longer than the second exhaust path 20. The flow path from the confluence 30 to the outlet 50 in the first exhaust path 10 is formed to be longer than the second exhaust path 20. Consequently, the gas flowing inside the first exhaust path 10 has a higher velocity. Therefore, in the flow path configuration where the first exhaust path 10 and the second exhaust path 20 are connected via the confluence port 43, the gas on the second exhaust path 20 side via the confluence port 43 is drawn toward the side with the higher velocity (the first exhaust path 10 side).

[0030] Furthermore, the second inlet 42 has the same cross-sectional area as the outlet 50, and opens in a direction different from that of the outlet 50. The outlet 50 is located below the battery pack 2 and opens downwards. The direction of the outlet 50 opening is opposite to the direction of the second inlet 42 opening. This prevents gas discharged from the outlet 50 from being drawn into the second inlet 42.

[0031] In addition, in order to reduce the temperature of the gas discharged from outlet 50, exhaust pipe 3 needs to reduce the temperature of the gas as it flows through the first exhaust path 10. The temperature of the outside air is lower than that of the gas. Therefore, by drawing in outside air from the second inlet 42 and supplying this outside air to the first exhaust path 10 from the confluence port 43, the gas mixes with the air in the confluence section 30, and the air can be used to reduce the temperature of the gas.

[0032] As explained above, according to the embodiment, by allowing the gas generated in the battery pack 2 to circulate in the exhaust pipe 3, the gas can be discharged from the outlet 50 at a reduced temperature.

[0033] Furthermore, there is no limitation on the number of battery cells contained in battery pack 2. For example, battery pack 2 can be a battery pack containing only one battery cell. That is, battery pack 2 only needs to have at least one battery cell.

[0034] Furthermore, the direction of the outlet 50 opening is not limited to downward; it can also be horizontal. Similarly, the direction of the second inlet 42 opening is not limited to upward; it can also be horizontal.

[0035] Alternatively, the exhaust duct 3 may have multiple second inlets 42. The exhaust duct 3 can be constructed to have both a first inlet 41 and a second inlet 42 relative to a single outlet 50, or multiple second inlets 42 may be provided.

[0036] Furthermore, the exhaust duct 3 is not limited to a duct composed of duct components. For example, the exhaust duct 3 may also be a structure composed of a frame or the like on the fuselage side. Alternatively, the exhaust duct 3 may be partially composed of duct components and the remaining part may be composed of components on the fuselage side. Figure 4 , Figure 5 This is an example of a variation of the energy storage device 1.

[0037] like Figure 4 , Figure 5 As shown, in the modified example, the energy storage device 1 is configured such that the exhaust pipe 3 has multiple second inlets 42. A portion of the exhaust pipe 3 is composed of a first component 31 and a second component 32 on the body side. The first component 31 is disposed above the battery pack 2. The second component 32 is disposed below the battery pack 2. Both the first component 31 and the second component 32 are composed of body-side sheet metal, heat-insulating material, heat-insulating sheets, etc.

Claims

1. An energy storage device, characterized in that, It has a battery pack containing at least one battery cell and an exhaust pipe for discharging gases generated inside the battery pack. The exhaust pipe connects the interior of the battery pack to the exterior of the energy storage device. The exhaust pipe has: A first exhaust path, in which gas generated inside the battery pack flows; The second exhaust path allows outside air to flow through it. and At the confluence section, the first exhaust path and the second exhaust path merge. The angle between the first exhaust path and the second exhaust path toward the confluence is less than 90 degrees.

2. The energy storage device according to claim 1, characterized in that, The exhaust pipe has: The first inlet is the inlet of the first exhaust path, and the gas generated inside the battery pack flows into the first inlet; The second inlet is the inlet of the second exhaust path, through which the external air flows into the second inlet; and The outlet, located downstream of the confluence section, discharges the gas mixed in the confluence section to the outside of the energy storage device. The first exhaust path allows gas flowing in from the first inlet to flow into the confluence section. The second exhaust path allows external air flowing in from the second inlet to circulate to the confluence.

3. The energy storage device according to claim 2, characterized in that, The first exhaust path is longer than the second exhaust path.

4. The energy storage device according to claim 3, characterized in that, The first exhaust path is an airflow formation path, through which the pressure inside the battery pack is higher than atmospheric pressure by the generation of the gas, forming a flow of the gas from the first inlet to the outlet; The second exhaust path draws in outside air from the second inlet by the negative pressure generated at the confluence of the gas flowing from the first inlet toward the outlet inside the first exhaust path.

5. The energy storage device according to claim 4, characterized in that, The second inlet has the same cross-sectional area as the outlet and opens in a direction different from the opening direction of the outlet.

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