Cyclone-type collection device for battery packs, and battery device equipped therewith

Abstract

To provide a cyclone-type collection device capable of suppressing the scattering of dust.SOLUTION: There is provided a cyclone-type collection device 30 for a battery pack 10 in which multiple battery cells 12 are stored in a pack case 14. When gas containing dust is discharged from the battery cells 12 inside the pack case 14, the cyclone-type collection device 30 for the battery pack is configured to generate a swirling flow in the gas discharged from the pack case 14 and centrifugally separate the dust contained in the gas.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a cyclone type collecting device for a battery pack and a battery device provided with the same.

Background Art

[0002] Conventionally, as a power source for vehicle driving or the like, a battery pack including a plurality of battery cells and a pack case that houses the plurality of battery cells has been used. Although the battery cells are usually hermetically sealed, for example, due to problems such as overcharging or physical external force, the hermetic state may be released and gas may be ejected. As prior art documents related to this, Patent Documents 1 and 2 are cited. For example, Patent Document 1 discloses an in-vehicle battery device including a battery cell having a gas discharge valve that discharges gas generated inside to the outside, a smoke flow path that collects the gas discharged from the gas discharge valve inside the pack case, and an exhaust duct that is connected to the smoke flow path and discharges the collected gas to the outside of the vehicle compartment.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the study by the present inventor, the gas ejected from the battery cell can be a subsonic flow. Therefore, the gas ejected from the battery cell may contain dust composed of the contents of the battery cell (for example, fragments of the active material layer), sparks, soot, etc. However, in the configuration of, for example, Patent Document 1, the gas mixed with dust is directly discharged to the outside through the exhaust duct. Therefore, there is a risk that the dust will be discharged to the outside and scattered around together with the gas. Further, if the gas contains sparks, there is a risk that the heat will also be transmitted to the surroundings.

[0005] This invention has been made in view of the above circumstances, and its purpose is to provide a novel cyclone-type dust collection device for a battery pack that can suppress the scattering of dust, and a battery device equipped therewith. [Means for solving the problem]

[0006] The present invention provides a cyclone-type collection device for use in a battery pack comprising a plurality of battery cells housed in a pack case, wherein when a gas mixed with dust is ejected from the battery cells inside the pack case, the device is configured to generate a swirling flow in the gas exhausted from the pack case, thereby centrifuging the dust contained in the gas.

[0007] With the above configuration, dust contained in the gas can be separated, thus effectively suppressing dust dispersion. In particular, suppressing spark dispersion can improve the safety of the battery pack. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a schematic side view of a battery device according to one embodiment. [Figure 2] Figure 2 is a schematic perspective view of a cyclone-type collection device. [Figure 3] Figure 3 is a schematic longitudinal cross-sectional view of a cyclone-type collection device. [Figure 4] Figure 4 is a schematic cross-sectional view of the second turning region. [Figure 5] Figure 5 is a streamline diagram of an airflow according to one embodiment. [Figure 6] Figure 6 is a streamline diagram of dust according to one embodiment. [Modes for carrying out the invention]

[0009] Hereinafter, preferred embodiments of the technology disclosed herein will be described with reference to the drawings. Matters other than those specifically mentioned herein but necessary for carrying out the present invention can be understood as design matters for those skilled in the art based on the prior art. The present invention can be carried out based on the contents disclosed herein and common technical knowledge in the art.

[0010] [Battery device] Figure 1 is a schematic side view of the battery device 100. In the following description, the symbols L, R, F, Rr, U, and D in the drawing represent left, right, front, rear, top, and bottom, respectively, and the symbols X, Y, and Z in the drawing represent the arrangement direction of the battery cells 12, the width direction of the battery cells 12 perpendicular to the arrangement direction X, and the vertical direction, respectively. However, these directions are merely for the convenience of explanation and do not in any way limit the installation configuration of the battery device 100. Also, each figure is a schematic diagram and does not necessarily faithfully reflect the actual product. In the following, the same symbols are used for components and parts that perform the same function, and redundant explanations are omitted or simplified as appropriate.

[0011] As shown in Figure 1, the battery device 100 includes a battery pack 10, an exhaust duct 20, and a cyclone-type collection device 30. The exhaust duct 20 connects the battery pack 10 and the cyclone-type collection device 30. However, the exhaust duct 20 is not essential; for example, the cyclone-type collection device 30 can be directly attached to the battery pack 10.

[0012] The battery pack 10 comprises a plurality of battery cells 12 and a pack case 14. The plurality of battery cells 12 are arranged in this case along the arrangement direction X. Although not shown in the figures, the plurality of battery cells 12 are electrically connected to each other. The battery cells 12 are storage batteries, for example, lithium-ion secondary batteries. In this specification, "storage battery" is a general term referring to energy storage devices that can be repeatedly charged and discharged, and is a concept that includes secondary batteries such as lithium-ion secondary batteries and nickel-metal hydride batteries, and capacitors such as lithium-ion capacitors.

[0013] Although not shown in the diagram, the battery cell 12 is constructed by housing an electrode body, including electrodes, and an electrolyte inside an outer casing. The configuration of the battery cell 12 may be the same as conventional designs and is not limited in any way. The electrodes typically include an active material layer containing an active material capable of intercalating and releasing charge carriers. In this example, the battery cell 12 has a flattened, bottomed rectangular parallelepiped shape (square). However, the shape of the battery cell 12 is not limited to a square shape and may be any shape, such as cylindrical or bag-shaped. The outer casing of the battery cell 12 may include a gas release valve that operates when the internal pressure rises.

[0014] The battery cell 12 is normally hermetically sealed. However, due to malfunctions such as overcharging or physical external forces, the hermetically sealed state of the battery cell 12 may be released, causing gas to be ejected from within. The ejected gas may be a subsonic flow. Therefore, the gas ejected from the battery cell 12 may contain dust. In this specification, "dust" refers to all solid suspended matter with a particle size (secondary particle size) of approximately 100 μm or less (for example, about 1 to 100 μm), and is a concept that includes the contents of the battery cell 12 (for example, fragments of the active material layer), sparks, soot, etc.

[0015] The pack case 14 is an enclosure that houses multiple battery cells 12 in a predetermined arrangement. The pack case 14 may also house, as appropriate, cooling devices such as cooling fans, control devices for controlling the charging and discharging of the battery cells 12, and sensors for measuring the current, voltage, temperature, etc., of the battery cells 12. The pack case 14 is preferably more durable and impact-resistant than the battery cells 12. The pack case 14 is preferably able to maintain its shape even when gas is ejected from the battery cells 12. The pack case 14 is preferably made of a metal material such as aluminum, aluminum alloy, iron, iron alloy, or stainless steel. The pack case 14 is provided with an outlet 15 that connects to an exhaust duct 20. When gas is ejected from the battery cells 12, the ejected gas flows out through the outlet 15 into the exhaust duct 20.

[0016] The exhaust duct 20 forms a gas flow path that connects the outlet 15 of the pack case 14 and the inlet 31 of the cyclone collector 30. The exhaust duct 20 has a bent portion here. This makes it easier to generate a swirling flow in a swirling chamber 34 (described later) of the cyclone collector 30. Also, it can prevent overly large fragments (such as the contents of the battery cell 12) from entering the cyclone collector 30. In this specification, "bent" includes not only bending with a definite angle but also a shape that gently curves in an arc shape, and broadly refers to a shape that is not a straight line in a cross-sectional view. However, in other embodiments, the exhaust duct 20 may be linear in a cross-sectional view.

[0017] Preferably, the exhaust duct 20 is provided with a relief valve (escape valve) that opens when the pressure inside the pack case 14 exceeds a predetermined value. Thereby, only when the pressure inside the pack case 14 exceeds a predetermined value (in other words, only when a predetermined amount or more of gas jets out from the battery cell 12), the pack case 14 and the cyclone collector 30 can be communicated. Also, the exhaust duct 20 may be provided with valve members other than the relief valve as appropriate, such as a check valve as described in Patent Document 1.

[0018] [Cyclone Collector] The cyclone collector 30 collects dust from the gas when a gas mixed with dust jets out from the battery cell 12 inside the pack case 14. Specifically, it generates a swirling flow (a spiral or toroidal air flow, also called a cyclone air flow, etc.) in the gas mixed with dust discharged from the battery cell 12, centrifugally separates and collects the dust contained in the gas. The cyclone collector 30 is configured here to be not normally communicated with the pack case 14 and to be communicated with the inside of the pack case 14 via the exhaust duct 20 when the relief valve opens.

[0019] Note that the cyclone collector 30 is a device (passive device) where gas only flows passively here. Therefore, electrical control is not required, and there is no need to provide sensors, control devices, etc. Thus, the device configuration can be simplified.

[0020] Figure 2 is a perspective view of the cyclone collector 30. Figure 3 is a longitudinal sectional view of the cyclone collector 30. In Figure 3, reference sign A1 represents the axis of the inner cylinder 33. Reference sign A1 is in the direction along the vertical direction Z. As shown in Figure 3, the cyclone collector 30 includes an inlet 31, a casing 32, an inner cylinder 33, a swirling chamber 34, two collection parts 35, 36, and two gas outlets 37, 38. Each part of the cyclone collector 30 is integrally formed here. As described above, the gas ejected from the battery cell 12 may contain sparks and dust. Therefore, it is preferable that each part of the cyclone collector 30 is made of a material with high heat resistance, such as metal materials like iron, iron alloy, stainless steel, copper, etc., or ceramics.

[0021] As shown in Figure 1, the inlet 31 communicates the exhaust duct 20 and the swirling chamber 34. As shown in Figure 3, the gas mixed with dust flows into the swirling chamber 34 from the inlet 31. The inlet 31 is provided in the casing 32 (specifically, the second side wall part 322 described later). The inlet 31 is a through hole penetrating the side surface of the casing 32. The inlet 31 is provided at the outer peripheral part of the swirling chamber 34. The inlet 31 is preferably provided so as to direct the flow of the gas flowing into the swirling chamber 34 in the circumferential direction of the axis A1 of the inner cylinder 33 to generate a swirling flow in the swirling chamber 34. The arrangement or angle of the inlet 31 is preferably determined based on, for example, the CAE analysis results (Figures 5 and 6) described later.

[0022] As shown in Figure 3, the casing 32 has a hollow structure. The casing 32 is provided rotationally symmetrically with respect to the axis A1 of the inner cylinder 33, except for the location where the inlet 31 is provided. The inner wall surface of the casing 32 partitions the swirling chamber 34. In this embodiment, the casing 32 has an upper wall portion 32u, a first side wall portion 321, a second side wall portion 322, and a tapered side wall portion 323. The first side wall portion 321 and the second side wall portion 322 are examples of "side wall portions". As shown in Figure 2, the upper wall portion 32u is circular in plan view. As shown in Figure 3, a portion of the inner cylinder 33 in the direction of the axis A1 protrudes from the center of the upper wall portion 32u.

[0023] As shown in Figure 3, the first side wall portion 321 extends downward from the outer edge of the upper wall portion 32u. The first side wall portion 321 extends in the direction of axis A1. The first side wall portion 321 has a cylindrical shape, more specifically, a substantially cylindrical shape. From the viewpoint of suitably generating a swirling flow in the swirling chamber 34 (more specifically, in the first swirling region 341 described later), it is preferable that the cross-section perpendicular to axis A1 of the first side wall portion 321 is circular. The first side wall portion 321 has a first diameter in the circumferential direction of axis A1. A collection portion 35, described later, is provided at the lower end of the first side wall portion 321.

[0024] The second side wall portion 322 is indirectly connected to the lower end of the first side wall portion 321. More specifically, the second side wall portion 322 is connected to the lower end of the first side wall portion 321 in a stepped manner. The second side wall portion 322 extends in the direction of axis A1. The second side wall portion 322 has a cylindrical shape, more specifically, a substantially cylindrical shape. From the viewpoint of suitably generating a swirling flow in the swirling chamber 34 (more specifically, in the second swirling region 342 described later), it is preferable that the cross section perpendicular to axis A1 of the second side wall portion 322 is circular. The second side wall portion 322 has a second diameter smaller than the first diameter of the first side wall portion 321 in the circumferential direction of axis A1. An inlet 31 is provided in the second side wall portion 322. A collection portion 36, described later, is provided at the lower end of the second side wall portion 322.

[0025] The tapered sidewall portion 323 is indirectly connected to the lower end of the second sidewall portion 322. More specifically, the tapered sidewall portion 323 is connected in a stepped manner from the lower end of the second sidewall portion 322. In cross-sectional view, the tapered sidewall portion 323 is an inclined surface that gradually decreases in diameter downwards. The tapered sidewall portion 323 has a frustoconical shape. The lower end of the tapered sidewall portion 323 constitutes a gas outlet 38, which will be described later. The tapered sidewall portion 323 is inclined toward the gas outlet 38. This allows for efficient gas discharge using a swirling flow.

[0026] The inner cylinder 33 extends in the direction of axis A1. The inner cylinder 33 has a constant diameter in the direction of axis A1. The inner cylinder 33 is cylindrical in shape. The inner cylinder 33 is fixed to the upper wall portion 32u of the casing 32. The inner cylinder 33 extends from the inside to the outside of the casing 32. A portion of the inner cylinder 33 in the direction of axis A1 (the upper end in Figure 3) protrudes to the outside of the casing 32, and the other portion in the direction of axis A1 is housed inside the casing 32. The first end of the inner cylinder 33 (the upper end in Figure 3) protrudes from the slewing chamber 34, and the second end in the direction of axis A1 (the lower end in Figure 3) is located inside the slewing chamber 34 (more specifically, inside the second slewing region 342, which will be described later).

[0027] The outer wall surface 33a of the inner cylinder 33 demarcates the swirling chamber 34 (specifically, the first swirling region 341 and the second swirling region 342, which will be described later). The inner cylinder 33 functions as a guide member for generating a swirling flow inside the swirling chamber 34 (around the outer wall surface). A baffle 33b is provided on the outer wall surface 33a of the inner cylinder 33. The baffle 33b is a flow straightening plate (a so-called baffle plate) that constitutes a flow path for smoothly swirling the gas inside the swirling chamber 34. Preferably, the baffle 33b is provided so as to direct the flow of gas inside the swirling chamber 34 in the circumferential direction of the axis A1 of the inner cylinder 33. The baffle 33b extends to the lower end of the communication port 33c of the inner cylinder 33.

[0028] The inner cylinder 33 functions as an exhaust passage for discharging gas from the swirling chamber 34. That is, the inner cylinder 33 is hollow. The inner cylinder 33 has openings at a first end and a second end in the direction of axis A1. The first end of the inner cylinder 33 in the direction of axis A1 (the end protruding from the swirling chamber 34) constitutes a gas outlet 37, which will be described later. The second end of the inner cylinder 33 in the direction of axis A1 (one end inside the swirling chamber 34) constitutes a communication port 33c that connects the inside and outside of the inner cylinder 33, in other words, the inside of the swirling chamber 34 and the inside of the inner cylinder 33. A baffle 33b is provided on the inner wall surface of the inner cylinder 33, similar to the outer wall surface 33a. Gas that has moved from the swirling chamber 34 to the inside of the inner cylinder 33 through the communication port 33c is discharged from the gas outlet 37, as shown by the arrow in Figure 3.

[0029] The swirling chamber 34 is a region where a swirling flow is generated by a dust-mixed gas that flows in through the inlet 31. In this embodiment, the swirling chamber 34 has a first swirling region 341 and a second swirling region 342 arranged coaxially. The first swirling region 341 and the second swirling region 342 are in communication. The first swirling region 341 and the second swirling region 342 are formed continuously here. In a plan view, the first swirling region 341 and the second swirling region 342 overlap. The second swirling region 342 is located vertically below the first swirling region 341. The heights (lengths in the vertical direction Z) of the first swirling region 341 and the second swirling region 342 are different from each other. The cross-sectional areas of the sections perpendicular to the axis A1 are different for the first swirling region 341 and the second swirling region 342. In this embodiment, the slewing chamber 34 is divided into a first slewing region 341 and a second slewing region 342, but in other embodiments, it may be a single substantially cylindrical space. The slewing chamber 34 may, for example, not have a first slewing region 341 and consist only of a second slewing region 342.

[0030] The first swirling region 341 constitutes the upper part of the swirling chamber 34 and is demarcated by the upper wall portion 32u and the first side wall portion 321 of the casing 32 and the outer wall surface 33a of the inner cylinder 33. The first swirling region 341 is an annular space. The first swirling region 341 is located above the inlet 31. The height (length in the vertical direction Z) of the first swirling region 341 is smaller than that of the second swirling region 342. The cross-sectional area of ​​the first swirling region 341 perpendicular to the axis A1 is larger than that of the second swirling region 342. Therefore, a relatively large centrifugal force can be applied to the dust in the gas in the first swirling region 341. A collection section 35 is provided in the first swirling region 341.

[0031] The second swirling region 342 constitutes the lower part of the swirling chamber 34 and is demarcated by the second side wall portion 322 of the casing 32 and the outer wall surface 33a of the inner cylinder 33. The second swirling region 342 is a substantially annular space. An inlet 31 is provided in the second swirling region 342. A collection portion 36 is provided in the second swirling region 342. In this specification, the side of the swirling chamber 34 that is relatively closer to the inner cylinder 33 is sometimes referred to as the "inner circumference side," and the side that is further away from the inner cylinder 33 and relatively closer to the casing 32 (first side wall portion 321 to second side wall portion 322) is sometimes referred to as the "outer circumference side."

[0032] The collection sections 35 and 36 are parts that collect dust separated by the swirling flow, specifically dust that collides with the inner wall surface of the casing 32 and falls along that inner wall surface. The collection sections 35 and 36 are each arranged in an annular shape in a plan view. The collection sections 35 and 36 are arranged coaxially. By providing two collection sections 35 and 36, dust can be collected efficiently. Although there are two collection sections 35 and 36 here, in other embodiments there may be one or three or more.

[0033] The collection section 35 is a recessed portion (concave) that is lowered within the first swirling region 341. The collection section 35 is a pocket that collects dust that has risen into the first swirling region 341 due to the swirling flow. The collection section 35 can collect more light dust than the collection section 36. The collection section 35 is located below the first side wall 321. Here, the collection section 35 is provided continuously from the lower end of the first side wall 321. This allows for efficient collection of centrifugalally separated dust. The collection section 35 is located above the second swirling region 342. The collection section 35 is located above the inlet 31. The collection section 35 is located further outward in the circumferential direction of axis A1 than the collection section 36.

[0034] The collection section 36 is a recessed portion (concave) that is lowered within the second swirling region 342. The collection section 36 is a pocket that collects dust that has descended within the second swirling region 342 due to the swirling flow. The collection section 36 can collect more heavier dust than the collection section 35. The collection section 36 is located below the second side wall 322. Here, the collection section 36 is provided continuously from the lower end of the second side wall 322. This allows for efficient collection of centrifugalally separated dust. The collection section 35 is located below the first swirling region 341. The collection section 36 is located below the inlet 31. The collection section 36 is located further inward in the circumferential direction of axis A1 than the collection section 35.

[0035] The gas outlets 37 and 38 are the parts that discharge the gas, from which dust has been separated by the swirling flow, to the outside of the cyclone-type collection device 30. The gas outlets 37 and 38 are located at the upper and lower ends (both ends in the direction of axis A1) of the cyclone-type collection device 30, respectively. Specifically, the gas outlet 37 is located above the swirling chamber 34, and the gas outlet 38 is located below the swirling chamber 34. This allows for efficient gas discharge using the swirling flow.

[0036] The gas outlet 37 is located at the first end of the inner cylinder 33 (the upper end in Figure 3). The gas outlet 37 opens upward. The gas outlet 38 is located at the lower end of the tapered side wall portion 323 of the casing 32. The gas outlet 38 opens downward. Filters, slits, etc., may be provided in the gas outlets 37 and 38 as appropriate. Although there are two gas outlets 37 and 38 in this embodiment, there may be only one in other embodiments.

[0037] [Airflow in a cyclone-type collection device] Figure 4 is a schematic cross-sectional view of the second swirling region 342. As shown in Figure 4, dust-mixed gas AF flows into the second swirling region 342 from the exhaust duct 20 (see Figure 1) through the inlet 31. This gas AF is a very fast airflow that can even be subsonic. Within the second swirling region 342, the incoming dust-mixed gas AF is directed in the circumferential direction of the axis A1 and rotates along the outer wall surface 33a of the inner cylinder 33 around the axis A1. This generates a powerful swirling flow within the second swirling region 342.

[0038] In Figure 4, the flow of gas AF is illustrated with arrows indicating that it makes approximately one full rotation within the second swirling region 342. However, as shown in the CAE analysis results (Figures 5 and 6) described later, a very large number of rotations actually occur, resulting in a powerful swirling flow. The rotation of gas AF in the second swirling region 342 occurs coaxially with axis A1. However, since gas AF flows continuously from the inlet 31, the movement changes direction along the inner cylinder 33, which is perpendicular to the plane of rotation, as it rotates, resulting in a swirling flow. As a result, the centrifugal force due to the swirling flow acts not only outward in the circumferential direction but also in a direction parallel to axis A1.

[0039] Within the second swirling region 342, a swirling flow is generated from the dust-mixed gas AF. Because dust particles, which have a greater mass than the gas, have higher kinetic energy due to centrifugal force, they orbit the outer periphery of the second swirling region 342 and collide with the second side wall 322. The dust particles that collide with the second side wall 322 fall along the second side wall 322 due to gravity and are collected (accumulated) in the collection section 36. Heavier dust particles are particularly easily collected in the collection section 36. As a result, the first dust particles contained in the gas are centrifuged.

[0040] Furthermore, some of the dust particles, influenced by lift and random motion due to collisions with other dust particles, move upward along the inner cylinder 33 in a swirling flow and reach the first swirling region 341. Within the first swirling region 341, similar to the second swirling region 342, the gas AF rotates along the outer wall surface 33a of the inner cylinder 33 around the axis A1, generating a strong swirling flow. Due to the generation of the swirling flow, dust particles, which have a larger mass than the gas, orbit the outer periphery of the first swirling region 341 and collide with the first side wall 321. The dust particles that collide with the first side wall 321 fall along the first side wall 321 due to gravity and are collected (deposited) in the collection section 35. This causes the second dust particles contained in the gas to be centrifuged. In the collection section 35, the proportion of lighter dust particles may be relatively higher than in the collection section 36.

[0041] As described above, the gas from which dust has been removed in the swirling chamber 34 reaches the upper wall portion 32u of the casing 32, and then moves downward along the inner cylinder 33 due to the swirling flow. Because the inner circumference of the swirling flow is under negative pressure, the gas passing near the inner cylinder 33 in the second swirling region 342 is drawn into the inner cylinder 33 through the communication port 33c of the inner cylinder 33. Then, as shown in Figure 3, the gas inside the inner cylinder 33 is discharged to the outside of the cyclone-type collection device 30 from the gas outlet 37 provided at the first end of the inner cylinder 33 (the upper end in Figure 3). On the other hand, the gas passing near the second side wall portion 322 of the second swirling region 342 moves further downward along the tapered side wall portion 323 and is discharged to the outside of the cyclone-type collection device 30 from the gas outlet 38 provided at the lower end of the tapered side wall portion 323. By providing gas outlets 37 and 38 above and below the swirling chamber 34 in this manner and diverting the gas flow, the discharge flow rate at each location can be reduced, and the flow velocity at the outlets can be lowered.

[0042] Furthermore, if a dust-mixed gas is ejected from the battery cell 12 inside the pack case 14, typically the entire battery unit 100, including the cyclone-type dust collection device 30, will need to be replaced. Therefore, the dust collected in the collection units 35 and 36 does not need to be removed from the collection units 35 and 36.

[0043] [Applications of battery devices] The battery device 100 can be used for various purposes, but is preferably mounted on vehicles such as passenger cars and trucks. The type of vehicle is not particularly limited, but may be, for example, an electric vehicle (BEV; Battery Electric Vehicle) powered solely by a motor powered by electricity supplied from the battery cell 12, or a hybrid vehicle (HEV; Hybrid Electric Vehicle) equipped with an internal combustion engine and a motor powered by electricity supplied from the battery cell 12. Furthermore, the hybrid vehicle may be a plug-in hybrid electric vehicle (PHEV; Plug-in Hybrid Electric Vehicle) in which the battery cell 12 can be charged by an external power source.

[0044] The following describes examples relating to the present invention, but it is not intended to limit the present invention to these examples.

[0045] [Fluid Simulation] Here, a cyclone-type dust collection device was designed under the following conditions, and the flow of gas and dust was simulated using CAE (Computer-Aided Engineering) analysis. <Cyclone-type collection device> • Material: Cast iron • Swivel chamber size: Diameter φ=150mm, height=200mm <Analysis conditions> • Analysis software: Star-CCM + (Manufactured by Siemens) ·Analysis method: Multiphase flow analysis <Gas mixed with dust> • Gas flow velocity: 100 m / s ·Particle density: 2.0g / cm 3 • Dust particle size: 40 μm

[0046] Figure 5 is a streamline diagram of the airflow obtained from CAE analysis. As shown in Figure 5, under the above conditions, a swirling flow was generated inside the cyclone-type collection device by the gas flowing in from the inlet, and the gas was discharged from both ends in the axial direction of the cyclone-type collection device. Figure 6 is a streamline diagram of the dust obtained from CAE analysis. As shown in Figure 6, under the above conditions, the dust flowing in from the inlet into the inside of the cyclone-type collection device (swirling chamber) (see Figure 6(A)) was carried by centrifugal force along the outer periphery of the swirling chamber (see Figure 6(B)) and eventually collected in the collection section (see Figure 6(C)).

[0047] Although embodiments of the present invention have been described above, these embodiments are merely examples. The present invention can be implemented in various other forms. The present invention can be implemented based on the contents disclosed herein and common technical knowledge in the art. The technologies described in the claims include various modifications and changes to the embodiments illustrated above.

[0048] As described above, specific embodiments of the technology disclosed herein include those described in the following sections. Item 1: A cyclone-type collection device for a battery pack comprising a plurality of battery cells housed in a pack case, wherein when a dust-mixed gas is ejected from the battery cells inside the pack case, the device is configured to generate a swirling flow in the gas exhausted from the pack case, thereby centrifuging and collecting the dust contained in the gas. Item 2: The cyclone collection device according to Item 1, comprising: a swirling chamber partitioned by a cylindrical side wall and the outer wall surface of an inner cylinder disposed inside the cylindrical side wall, wherein a swirling flow is generated along the inner cylinder; an inlet for introducing the dust-mixed gas into the swirling chamber; at least one collection unit provided below the side wall for collecting dust separated by centrifugal force from the gas; and at least one gas outlet for discharging the gas from which the dust has been separated to the outside. Item 3: The cyclone collection device according to Item 2, wherein the gas outlets are multiple, and are provided above and below the swirling chamber, respectively. Item 4: The cyclone collection device according to item 2 or 3, wherein the inner cylinder is hollow, with a first axial end protruding from the swirling chamber to form the gas outlet, and a second axial end positioned within the swirling chamber to form a communication port connecting the swirling chamber and the inside of the inner cylinder, and at least a portion of the gas from which the dust has been separated moves into the inside of the inner cylinder through the communication port by the swirling flow and is discharged from the gas outlet at the first end of the inner cylinder. Item 5: A cyclone collection device according to any one of items 2 to 4, further having a frustoconical tapered side wall portion connected to the lower end of the cylindrical side wall portion and gradually decreasing in diameter downward, wherein the lower end of the tapered side wall portion constitutes the gas outlet, and at least a portion of the gas from which the dust has been separated is discharged from the gas outlet at the lower end of the tapered side wall portion by the swirling flow. Item 6: The inlet is provided in the side wall portion, and the cyclone collection device is as described in any one of Items 2 to 5. Item 7: The swirling chamber comprises two regions arranged coaxially with the inner cylinder and in communication, the first swirling region being partitioned by a first side wall portion of the side wall portion and the outer wall surface of the inner cylinder, and the second swirling region being partitioned by a second side wall portion of the side wall portion and the outer wall surface of the inner cylinder, and the inlet being provided therein, the collection portion being provided in the first swirling region and the second swirling region, respectively, the cyclone collection device according to any one of items 2 to 6. Item 8: The cyclone collection device according to Item 7, wherein the second swirling region is located vertically below the first swirling region. Item 9: The cyclone collection device according to item 7 or 8, wherein the first swirling region and the second swirling region have different cross-sectional areas perpendicular to the axis of the inner cylinder. Item 10: The cyclone collection device according to any one of items 2 to 9, wherein the collection section is provided continuously from the lower end of the side wall. Item 11: The cyclone collection device according to any one of items 2 to 10, wherein the collection section is arranged in a ring shape. Item 12: A battery device comprising a battery pack comprising a plurality of battery cells housed in a pack case, and a cyclone collection device as described in any one of items 1 to 11. [Explanation of Symbols]

[0049] 10 battery packs 12 battery cells 14-pack case 20 Exhaust duct 30 Cyclone-type collection device 31 Inlet 32 Casing 321 First side wall section 322 Second side wall section 323 Tapered sidewall 33 Inner cylinder 33a External wall surface 33c communication port 34 Turning room 341 1st turning area 342 2nd turning area 35, 36 Collection section 37, 38 Gas outlets 100 Battery Unit A1 axis

Claims

1. A cyclone-type collection device used in a battery pack composed of multiple battery cells housed in a pack case, When a dust-mixed gas is ejected from the battery cell inside the pack case, the device is configured to generate a swirling flow in the gas being exhausted from the pack case, thereby centrifuging and collecting the dust contained in the gas. A swirling chamber is defined by a cylindrical side wall and the outer wall surface of an inner cylinder disposed inside the cylindrical side wall, and a swirling flow is generated along the inner cylinder. An inlet for introducing the aforementioned dust-mixed gas into the swirling chamber, A collection unit is provided below the side wall portion for collecting dust particles centrifuged from the gas, At least one gas outlet for discharging the gas from which the dust has been separated to the outside, Equipped with, The side wall portion comprises a first side wall portion and a second side wall portion connected to the lower end of the first side wall portion. The swivel chamber consists of two regions arranged coaxially with the inner cylinder and connected to each other, A first rotational region is defined by the first side wall portion and the outer wall surface of the inner cylinder, A second swirling region is provided, which is partitioned by the second side wall and the outer wall surface of the inner cylinder, and the inlet is located therein. Includes, The collection section is provided in the first swirling region and the second swirling region, respectively, and includes a first collection section which is positioned above the inlet and is a concave portion that is recessed downward within the first swirling region, and a second collection section which is a concave portion that is recessed downward within the second swirling region. A cyclone-type collection device for battery packs.

2. The aforementioned gas outlets are multiple, The following are provided above and below the aforementioned rotating chamber: The cyclone-type collection device according to claim 1.

3. The inner cylinder is hollow, The first end in the axial direction protrudes from the swivel chamber and constitutes the gas outlet. The second end in the axial direction is positioned inside the slewing chamber and forms a communication port that connects the slewing chamber with the inside of the inner cylinder. At least a portion of the gas from which the dust has been separated moves into the inner cylinder through the communication port by the swirling flow and is discharged from the gas outlet at the first end of the inner cylinder. The cyclone-type collection device according to claim 1.

4. It further has a frustoconical tapered side wall portion connected to the lower end of the second side wall portion, which gradually decreases in diameter downwards. The lower end of the tapered side wall portion constitutes the gas outlet. At least a portion of the gas from which the dust has been separated is configured to be discharged by the swirling flow from the gas outlet at the lower end of the tapered side wall. The cyclone-type collection device according to claim 1.

5. The inlet is provided in the second side wall, The cyclone-type collection device according to claim 1.

6. The second turning region is located vertically below the first turning region. The cyclone-type collection device according to claim 1.

7. The first pivoting region located on the upper side has a cross-sectional area perpendicular to the axis of the inner cylinder that is larger than that of the second pivoting region. The first collection unit is located further outward in the circumferential direction of the axis than the second collection unit. The cyclone-type collection device according to claim 1.

8. The first collection portion is annular in shape and is provided continuously from the lower end of the first side wall portion, The second collection section is annular in shape and is provided continuously from the lower end of the second side wall. The cyclone-type collection device according to claim 1.

9. A battery pack consisting of multiple battery cells housed in a pack case, A cyclone-type collection device according to any one of claims 1 to 8, A battery device equipped with the following features.

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