Battery pack

Abstract

A battery pack according to one embodiment of the present invention may include: a pack housing having a gas outlet and a venting passage connected to the gas outlet; a pack unit having at least one battery cell disposed in the pack housing; and a sedimentation unit provided in the venting passage and settling particles present in the venting gas by changing the cross-sectional area of ​​the venting passage.

Description

Technology Field

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

[0003] Rechargeable batteries are rechargeable batteries with a vast range of applications, extending from relatively small portable electronic devices to medium-to-large automobiles and power storage systems.

[0004] The secondary battery can be used in the form of a secondary battery cell, wherein the secondary battery cell has a form in which a laminate of a positive electrode, a negative electrode, and a separator is arranged inside an outer casing and filled with an electrolyte.

[0005] By electrically connecting multiple of these secondary battery cells to form a battery pack, the capacity and output of the battery can be increased.

[0006] Many secondary battery cells present in a battery pack are exposed to various events such as overcharging, exposure to heat, or external impact. Due to these events, internal materials of the secondary battery cells, such as electrodes, may decompose, and the decomposed materials may be released to the outside of the battery pack in the form of high-temperature dust.

[0007] When high-temperature dust emitted from the battery pack comes into contact with venting gas in the air, flames may ignite on the outside of the battery pack. This is a flame that can occur regardless of whether flames are generated inside the battery pack, and it can cause secondary fires in the vehicle's internal parts. Prior art literature

[0009] (Patent Document 0001) KR 10-2019-0041727 A (2019.04.23) The problem to be solved

[0010] One objective of the present invention is to prevent short circuits and ignition of a battery pack and to improve the safety of the battery pack.

[0011] In addition, the present invention has the purpose of blocking the release of flammable material and flames to the outside of the battery pack. means of solving the problem

[0013] A battery pack according to one embodiment of the present invention comprises: a pack housing having a gas outlet and a venting channel connected to the gas outlet; a plurality of pack units each having at least one battery cell disposed in the pack housing and a busbar unit electrically connected to the battery cell; and a sedimentation unit provided in the venting channel and changing the cross-sectional area of ​​the venting channel to precipitate particles present in the venting gas. The busbar unit includes a busbar member electrically connected to the battery cell and a busbar frame supporting the busbar member. The busbar frames of each of the plurality of adjacent pack units face and contact each other. The venting channel includes a second venting channel facing the inner surface of each of the busbar frames of the plurality of adjacent pack units. The sedimentation unit can change the cross-sectional area of ​​the second venting channel to precipitate particles present in the venting gas into the second venting channel.

[0014] In addition, in one embodiment, the sedimentation unit may include a cross-sectional area changing member having a first hollow having a cross-sectional area narrower than the cross-sectional area of ​​the venting channel, through which venting gas flows.

[0015] In addition, in one embodiment, the busbar member is connected to the electrode tab of the battery cell, and the busbar unit further comprises at least one cell venting hole, and the venting passage further comprises a first venting passage formed inside the pack housing; and the second venting passage may be formed between the plurality of mutually adjacent pack units or between the pack housing and the pack unit and connected to the cell venting hole.

[0016] In addition, in one embodiment, at least one cell venting hole may be formed in the busbar frame.

[0017] In addition, in one embodiment, the cross-sectional area changing member is provided in the first venting channel, the second venting channel, and the cell venting hole, and its outer surface can be in close contact with the inner surface of the pack housing and the inner surface of the busbar frame.

[0018] In addition, in one embodiment, the width of the first hollow of the cross-sectional area changing member can change in the direction of the flow of the venting gas in the cross-section in the thickness direction of the pack housing.

[0019] In addition, in one embodiment, the first hollow of the cross-sectional area change member includes an inlet, an intermediate flow path connected to the inlet, and an outlet connected to the intermediate flow path in the thickness direction cross-section of the pack housing, wherein the inlet width value, which is the width value of the inlet, is the minimum or maximum value of the width value of the first hollow, and the outlet width value, which is the width value of the outlet, has a value different from the inlet width value among the minimum value and the maximum value, and the intermediate flow path width value, which is the width value of the intermediate flow path, may have a plurality of values.

[0020] In addition, in one embodiment, the first hollow of the cross-sectional area change member may have a single width value in the thickness direction cross-section of the pack housing.

[0021] In addition, in one embodiment, the busbar frame may include a first protruding area, which is an area protruding above the uppermost level of the battery cell in the thickness direction cross-section of the pack housing.

[0022] In addition, in one embodiment, a unit cover member covering the battery cell; and a pack cover member covering the unit cover member and the busbar frame may be further included.

[0023] In addition, in one embodiment, the busbar frame has a multi-stage shape in the thickness direction cross-section of the pack housing, and the pack cover member includes a second protruding area which is an area protruding in the direction of the busbar frame; and the second protruding area can be in close contact with the unit cover member and the busbar frame.

[0024] In addition, in one embodiment, the busbar frame may include at least one of a straight section, a curved section, and an inclined section in the cross-section in the thickness direction of the pack housing.

[0025] In addition, in one embodiment, the cross-sectional area changing member comprises a first cross-sectional area changing member and a second cross-sectional area changing member disposed opposite each other at at least one of the cell venting hole, the first venting channel, and the second venting channel, wherein the first cross-sectional area changing member may have a plurality of values ​​for the width of the first hollow, and the second cross-sectional area changing member may have a single value for the width of the first hollow.

[0026] In addition, in one embodiment, a flashback prevention unit disposed at at least one of the gas outlet, the first venting channel, the second venting channel, and the cell venting hole may be further included.

[0027] In addition, in one embodiment, the flashback prevention unit may include a flashback prevention member having a plurality of holes. Effects of the invention

[0029] According to the present invention, short circuits and ignition of the battery pack are prevented, and the safety of the battery pack is improved.

[0030] In addition, according to the present invention, the release of flammable material and flames to the outside of the battery pack is blocked. Brief explanation of the drawing

[0032] FIG. 1 is a cross-sectional view of a portion of a battery pack according to one embodiment of the present invention. Figure 2 is a front view along line II' of Figure 1. Figure 3 is an enlarged view of area A in Figure 2. FIG. 4 is an enlarged view of area A of FIG. 2 according to another embodiment of the present invention. FIG. 5 is an enlarged view of area A of FIG. 2 according to another embodiment of the present invention. FIG. 6 is an enlarged view of area A of FIG. 2 according to another embodiment of the present invention. FIG. 7 is an enlarged view of area B of FIG. 2 according to another embodiment of the present invention. FIG. 8 is an enlarged view of area B of FIG. 2 according to another embodiment of the present invention. FIG. 9 is an enlarged view of area B of FIG. 2 according to another embodiment of the present invention. FIG. 10 is an enlarged view of area B of FIG. 2 according to another embodiment of the present invention. FIG. 11 is a cross-sectional view of a portion of a battery pack according to another embodiment of the present invention. FIG. 12 is a cross-sectional view of a part of a battery pack according to another embodiment of the present invention. FIG. 13 is a cross-sectional view of a first venting channel according to one embodiment of the present invention. FIG. 14 is a cross-sectional view of a first venting channel according to another embodiment of the present invention. FIG. 15 is a cross-sectional view of a first venting channel according to another embodiment of the present invention. FIG. 16 is a cross-sectional view of a first venting channel according to another embodiment of the present invention. FIG. 17 is a cross-sectional view of a first venting channel according to another embodiment of the present invention. FIG. 18 is a cross-sectional view of a first venting channel according to another embodiment of the present invention. Specific details for implementing the invention

[0033] To aid in understanding the description of the embodiments of the present invention, elements indicated by the same reference numeral in the attached drawings are the same elements, and among the components that perform the same function in each embodiment, related components are indicated by the same or extensional numbers.

[0034] In addition, to clarify the gist of the present invention, descriptions of elements and techniques well known by the prior art are omitted, and the present invention will be described in detail below with reference to the attached drawings.

[0035] However, the concept of the present invention is not limited to the embodiments presented, and may be proposed by those skilled in the art in other forms in which specific components are added, changed, or deleted; it should be noted that such forms are also included within the scope of the same concept as the present invention.

[0036] Hereinafter, the X-axis in the attached drawings represents the width direction of the battery cell, the Y-axis represents the thickness direction of the battery cell, and the Z-axis represents the height direction of the battery cell. However, these directions are arbitrarily set for the convenience of explanation.

[0038] FIG. 1 is a cross-sectional view of a part of a battery pack according to one embodiment of the present invention. FIG. 1 is a view of the battery pack from a plan view, showing only the pack housing (110) of the battery pack in cross-section. FIG. 2 is a front view along line II' of FIG. 1.

[0039] As shown in FIGS. 1 and 2, a battery pack according to one embodiment of the present invention may include a pack housing (110) that accommodates at least one battery cell (121). A modularized battery cell (121) may be accommodated in the pack housing (110), or a plurality of battery cells (121) may be directly accommodated in the pack housing (110).

[0040] A method of mounting a modularized battery cell (121) onto a pack housing (110) involves mounting a plurality of battery cells (121) onto a module housing (not shown) and mounting the module housing onto the pack housing (110) to form a battery pack.

[0041] A battery pack may be configured by omitting the modularization of the battery cells (121) and directly mounting a plurality of battery cells (121) onto the pack housing (110). In one embodiment of the present invention, a pack unit (120) including a plurality of battery cells (121) may be directly mounted onto the pack housing (110) without a separate module housing (not shown).

[0042] The pack housing (110) may have a shape in which at least a portion of its interior is empty, and the empty area inside the pack housing (110) may become a first venting passage (112). The first venting passage (112) serves as a passage through which venting gas, particles, flames, etc. generated from the battery cell (121) can travel. The first venting passage (112) may be formed in a direction parallel to the width direction of the battery cell (121) and may be formed in multiple places in the pack housing (110).

[0043] The pack housing (110) may include a gas outlet (111) that connects the first venting passage (112) to the outside of the pack housing (110). Venting gas, particles, flames, etc. present in the first venting passage (112) may be discharged to the outside of the pack housing (110) through the gas outlet (111). Multiple gas outlets (111) may be formed in the pack housing (110).

[0044] At least one pack unit (120) may be accommodated in the pack housing (110). The pack unit (120) may include at least one battery cell (121) and at least one pad (124) in contact with the battery cell (121). The pad (124) may contact the battery cell (121) to respond to volume expansion of the battery cell (121) or to perform cooling of the battery cell (121).

[0045] A single pack unit (120) may include a busbar unit (140) that supports a plurality of electrode tabs (122) drawn from the positive (not shown) and negative (not shown) of a battery cell (121), respectively.

[0046] The busbar unit (140) may include a busbar member (141) electrically connected to an electrode tab (122) of a battery cell (121) and a busbar frame (142) supporting the busbar member (141).

[0047] A single pack unit (120) may include a plurality of busbar members (141), and the plurality of busbar members (141) may be provided as a busbar member (141) in contact with an electrode tab (122) drawn out to one side of a battery cell (121) and another busbar member (141) in contact with another electrode tab (122) drawn out to the other side of the battery cell (121). The busbar members (141) and the electrode tabs (122) may be interconnected by welding.

[0048] A busbar member (141) in contact with an electrode tab (122) drawn out to one side of a battery cell (121) may be provided in a single or divided form and may be connected to the entire electrode tab (122) drawn out to one side of the battery cell (121).

[0049] A busbar member (141) in contact with an electrode tab (122) connected to the other side of the battery cell (121) may also be provided in a single or divided form and may be connected to the entire electrode tab (122) drawn out to the other side of the battery cell (121).

[0050] A single pack unit (120) may include a plurality of busbar frames (142). One of the busbar frames (142) may be positioned on one side of the battery cell (121), and another of the busbar frames (142) may be positioned on the other side of the battery cell (121). The plurality of busbar frames (142) may be spaced apart from each other in the X-axis direction with the battery cell (121) in between.

[0051] The above busbar frame (142) can perform the function of supporting the battery cell (121) within the pack housing (110), and may be in close contact with the pack housing (110) or fixed to the pack housing (110) by a separate connecting member (not shown). According to this, a plurality of battery cells (121) can be fixed to the pack housing (110) without a module housing (not shown). A battery pack without a module housing (not shown) is lighter because its weight is further reduced, and productivity is increased because the assembly process is simplified.

[0052] The busbar frame (142) may have a certain length in the direction in which a plurality of battery cells (121) are stacked, and a busbar member (141) may be fixed to the surface of the busbar frame (142) facing the battery cells (121).

[0053] A cell venting hole (143), which is a through hole, may be formed in the busbar frame (142). The cell venting hole (143) is a hole formed in the thickness direction of the busbar frame (142) and may serve as a passage for venting gas, particles, and flames generated from the battery cell (121) to pass through.

[0054] The busbar frame (142) may have a plurality of cell venting holes (143), and the plurality of cell venting holes (143) may be spaced apart from each other in the stacking direction of the battery cells (121).

[0055] As shown in FIG. 2, a plurality of pack units (120) may exist in the pack housing (110). In the pack housing (110), the plurality of pack units (120) may be adjacent to each other in the X-axis direction. In one embodiment of the present invention, the pack units (120) may include a first pack unit (120a) located on one side of the pack housing (110), a second pack unit (120b) adjacent to the first pack unit (120a), a third pack unit (130c) adjacent to the second pack unit (120b), and a fourth pack unit (120d) adjacent to the third pack unit (130c).

[0056] Busbar frames (142) of pack units (120) adjacent to each other in the X-axis direction in the pack housing (110) may face each other. A busbar frame (142) supporting a busbar member (141) connected to one side electrode tab (122) of a first pack unit (120a) may come into contact with a busbar frame (142) supporting a busbar member (141) connected to the other side electrode tab (122) of a second pack unit (120b).

[0057] In one embodiment of the present invention, the busbar frame (142) may have a shape in which a bent portion is formed at a position spaced apart from both ends, and may have a 'U' shape. Both ends of the busbar frame (142) of the first pack unit (120a) may come into contact with both ends of the busbar frame (142) of the second pack unit (120b). By doing so, a series of spaces surrounded by the inner surfaces (142a) of the plurality of busbar frames (142) may be formed, and this space may become the second venting channel (123). Accordingly, the inner surface (142a) of the busbar frame (142) may be in a shape facing the second venting channel (123), and the cross-sectional area of ​​the space formed by the inner surface (142a) of the busbar frame (142) may become the cross-sectional area of ​​the second venting channel (123).

[0058] However, the busbar frame (142) included in the fourth pack unit (120d) located outermost in the X-axis direction of the pack housing (110) may face the inner surface of the pack housing (110). Here, the second venting channel (123) may be formed by the inner surface (142a) of one busbar frame (142) included in the fourth pack unit (120d) and the inner surface of the pack housing (110). The cross-sectional area of ​​the second venting channel (123) located at this position may be narrower than the cross-sectional area of ​​the second venting channel (123) located between the pack units (120). This applies equally even when one busbar frame (142) included in the first pack unit (120a) faces the inner surface of the pack housing (110).

[0060] As shown in FIG. 1, the second venting channel (123) can be formed parallel to the stacking direction of the battery cell (121) and can be a passage through which at least one of the venting gas, particles, and flames introduced through the cell venting hole (143) travels.

[0061] The second venting channel (123) may exist in multiple numbers, and a connector (113) may be formed in the area of ​​the pack housing (110) facing the second venting channel (123). The connector (113) is a hole penetrating the pack housing (110) in the Y-axis direction and can serve to connect the second venting channel (123) to the first venting channel (112).

[0062] In one embodiment of the present invention, a sedimentation unit (130) may be provided in at least one of the cell venting hole (143), the first venting channel (112), and the second venting channel (123). The sedimentation unit (130) is configured to change the cross-sectional area of ​​the cell venting hole (143), the first venting channel (112), and the second venting channel (123), and according to this sedimentation unit (130), the flow rate of the venting gas can be changed.

[0063] When the flow rate of the venting gas is changed by the sedimentation unit (130), particles of a combustible material contained in the venting gas can be settled in at least one of the cell venting hole (143), the first venting channel (112), and the second venting channel (123).

[0064] Since the settled particles cannot be discharged to the outside of the pack housing (110) through the gas outlet (111), it is possible to prevent the release of flammable material, which is a necessary element for ignition, to the outside of the battery pack. According to this, secondary damage caused by fire can be prevented in electric vehicles, energy storage systems, etc.

[0065] In one embodiment of the present invention, the sedimentation unit (130) may include a plurality of cross-sectional area changing members (131) provided in the first venting channel (112) and the second venting channel (123).

[0066] The cross-sectional area changing member (131) may have a first hollow (132) having a cross-sectional area narrower than the cross-sectional area of ​​the first venting channel (112) and the cross-sectional area of ​​the second venting channel (123). The first hollow (132) is a channel formed inside the cross-sectional area changing member (131) and may serve as a passage for venting gas, particles, and flames to travel.

[0067] The length of the cross-sectional area changing member (131) can be appropriately selected and applied according to the flow characteristics of the venting gas, and the length of the first hollow (132) can be at least the same as the length of the cross-sectional area changing member (131).

[0068] The cross-sectional area changing member (131) present in the first venting channel (112) may have its outer surface in close contact with the inner surface of the pack housing (110). The outer surface of the cross-sectional area changing member (131) and the inner surface of the pack housing (110) may be provided to have an intermediate fit or interference fit tolerance. Accordingly, the cross-sectional area changing member (131) can be fixed to the pack housing (110) without a separate connecting member.

[0069] A cross-sectional area changing member (131) may be provided in a plurality in the first venting channel (112), and the plurality of cross-sectional area changing members (131) may be spaced apart from each other. The cross-sectional area changing member (131) may be positioned in the first venting channel (112) at a location corresponding to one pack unit (120). The value of the length of the cross-sectional area changing member (131) in the first venting channel (112) may be smaller than the value of the width of the battery cell (121). Accordingly, the venting gas introduced into the first venting channel (112) through the second venting channel (123) and the connector (113) can be easily introduced into the first hollow (132).

[0070] In addition, in one embodiment of the present invention, the cross-sectional area of ​​the second venting channel (123), the cross-sectional area of ​​the connector (113), the cross-sectional area of ​​the first venting channel (112), and the cross-sectional area of ​​the first hollow (132) can be made different from each other so that the venting gas undergoes a change in the cross-sectional area of ​​a plurality of channels. According to this, since a plurality of sections where the flow velocity changes can be formed, the section where particles settle due to the change in the flow velocity of the venting gas can be further increased, and the amount of settled particles can be increased.

[0071] In one embodiment of the present invention, a cross-sectional area changing member (131) may be provided in a plurality in the second venting channel (123). In the second venting channel (123), the cross-sectional area changing member (131) may be arranged between the cell venting holes (143). The outer surface of the cross-sectional area changing member (131) may be in close contact with the inner surface (142a) of the busbar frame (142). The outer surface of the cross-sectional area changing member (131) and the inner surface of the busbar frame (142) may be joined by mutual fit tolerances, but may also be joined by a separate adhesive or the like. However, this is not necessarily limited by the present invention and may be appropriately selected and applied considering the specifications of the battery pack, etc.

[0072] In addition, in FIG. 2, the shape of the first hollow (132) of the cross-sectional area change member (131) is shown as a circle, but the shape of the first hollow (132) may be a polygon, or a shape including straight lines and curves.

[0073] The length value of the cross-sectional area change member (131) present in the second venting channel (123) may be less than or equal to the separation distance value between the cell venting holes (143). Accordingly, the venting gas can be easily introduced into the second venting channel (123) through the busbar frame (142).

[0074] In one embodiment of the present invention, the width (W) of the first hollow (132) of the cross-sectional area changing member (131) may have a constant value in the longitudinal direction of the cross-sectional area changing member (131). The value of the width (W) of the first hollow (132) may have a value different from the value of the width of the cell venting hole (143), the value of the width of the first venting channel (112), the value of the width of the connector (113), and the value of the width of the second venting channel (123). Accordingly, the cross-sectional area changing section of the channel through which the venting gas flows can be increased, thereby allowing a larger amount of particles to be settled.

[0076] FIG. 3 is an enlarged view of area A of FIG. 2, showing a part of the battery cell (121) and a part of the busbar frame (142) according to another embodiment of the present invention.

[0077] In another embodiment of the present invention, the cross-sectional area changing member (131) may also be provided in the cell venting hole (143 in FIG. 2).

[0078] The cross-sectional area changing member (131) inserted into the cell venting hole (143) may have its outer surface in contact with the inner surface of the busbar frame (142). The outer surface of the cross-sectional area changing member (131) and the inner surface of the cell venting hole (143) may be provided to have mutual intermediate fit or interference fit tolerances. Accordingly, the cross-sectional area changing member (131) can be fixed within the cell venting hole (143) without a separate connecting member. If necessary, an adhesive may be applied to the outer surface of the cross-sectional area changing member (131), but this is not necessarily limited by the present invention and may be appropriately selected and applied depending on the specifications of the battery pack, the environment in which the battery pack is used, etc.

[0079] The width (W) of the first hollow (132) of the cross-sectional area change member (131) may be constant in the X-axis direction, and the value of the width (W) of the first hollow (132) may be a single value. When comparing the width (W) of the first hollow (132) and the width of the second venting channel (123) in the Z-axis direction in the same cross-section, the width (W) of the first hollow (132) may have a smaller value than the width of the second venting channel (123) in the Z-axis direction.

[0080] The venting gas generated from the battery cell (121) flows into the first hollow (132) and can move to the second venting passage (123) facing the inner surface of the busbar frame (142). The venting gas moving at a first flow rate in the first hollow (132) has a second flow rate in the second venting passage (123).

[0081] Since the cross-sectional area of ​​the first hollow (132) is narrower than the cross-sectional area of ​​the second venting channel (123), the first flow velocity may be faster than the second flow velocity under the same pressure conditions. As the venting gas enters the second venting channel (123), the flow velocity decreases rapidly, and because it moves through the second venting channel (123) at a flow velocity that is rapidly slower than the flow velocity in the first hollow (132), a large number of particles contained in the venting gas settle to the bottom in the second venting channel (123).

[0082] Particles in contact with the bottom surface in the Z-axis direction of the busbar frame (142) may stop moving while in contact with the busbar frame (142) or may stop moving while floating at a low speed in the second venting channel (123). Therefore, the escape of a number of particles contained in the venting gas from the second venting channel (123) can be minimized or prevented.

[0083] The particles contained in the venting gas may be components constituting the electrode (not shown) and separator (not shown) of the battery cell (121), or components constituting the battery cell (121) and the battery pack, and are mostly composed of flammable materials. Therefore, by minimizing or preventing particles containing flammable materials from escaping the second venting path (123), it is possible to minimize or prevent flammable materials, which are one of the ignition factors, from escaping to the outside of the battery pack.

[0085] FIG. 4 is an enlarged view of area A of FIG. 2, showing a part of the battery cell (121) and a part of the busbar frame (142) according to another embodiment of the present invention.

[0086] In another embodiment of the present invention, the cross-sectional area changing member (131) may also be provided in the cell venting hole (143 in FIG. 2).

[0087] In another embodiment of the present invention, the width (W) of the first hollow (132) of the cross-sectional area changing member (131) can be varied in the X-axis direction.

[0088] The X-axis direction is the direction in which the venting gas generated from the battery cell (121) moves to the second venting channel (123), and the width (W) of the first hollow (132) of the cross-sectional area change member (131) can change in the direction of the flow of the venting gas.

[0089] The first hollow (132) of the cross-sectional area change member (131) may be configured to include an inlet (133) facing the battery cell (121) in the thickness direction cross section of the pack housing (110), i.e., the XZ plane, an intermediate channel (134) that is connected to the inlet (133) and has a certain length in the X-axis direction, and an outlet (135) that is connected to the intermediate channel (134) and faces the second venting channel (123).

[0090] The value of the width (W) of the first hollow (132) of the cross-sectional area change member (131) may include the value of the inlet width (W1), which is the width in the Z-axis direction of the inlet (133), the value of the intermediate flow path width (W2), which is the width in the Z-axis direction of the intermediate flow path (134), and the value of the outlet width (W3), which is the width in the Z-axis direction of the outlet (135).

[0091] The intermediate flow path width (W2) shown in FIG. 4 indicates only the value of the width in the Z-axis direction from the center point in the X-axis direction of the intermediate flow path to improve the readability of the drawing. However, the intermediate flow path width (W2) may include the remaining widths among the widths (W) of the first hollow (132), excluding the inlet width (W1) and the outlet width (W3). In one embodiment of the present invention, the intermediate flow path width (W2) has multiple values ​​as it varies along the X-axis, and the number may differ for each embodiment.

[0092] In one embodiment of the present invention, the value of the inlet width (W1) may be the maximum value among the values ​​of the width (W) of the first hollow (132). In this case, the value of the outlet width (W3) may be the minimum value among the values ​​of the width (W) of the first hollow (132), and the value of the intermediate flow path width (W2) may be a value within the range of less than or equal to the value of the inlet width (W1) and greater than or equal to the value of the outlet width (W3).

[0093] The value of the intermediate channel width (W2) may be a value corresponding to the width of the intermediate channel in a direction parallel to the Z-axis from any point on the X-axis within the range of the intermediate channel. The intermediate channel width (W2) shown in FIG. 4 is the width of the intermediate channel in a direction parallel to the Z-axis from the center point in the X-axis direction of the intermediate channel as described above, but the intermediate channel width (W2) may be any one of the values ​​within the range of the intermediate channel that is less than or equal to the value of the inlet width (W1) and greater than or equal to the value of the outlet width (W3).

[0094] The intermediate flow path width (W2) may have multiple values ​​within a range of less than or equal to the value of the inlet width (W1) and greater than or equal to the value of the outlet width (W3). The multiple values ​​of the intermediate flow path width (W2) may include values ​​identical to the inlet width (W1) and values ​​identical to the outlet width (W3), as well as values ​​different from the inlet width (W1) and the outlet width (W3).

[0095] In one embodiment of the present invention, the intermediate channel may have a stepped shape in the X-axis direction. The width of the intermediate channel may decrease as it moves in the +X direction, and may include multiple sections where the width decreases rapidly. In the sections where the width decreases rapidly, the width of the intermediate channel may decrease linearly or non-linearly.

[0096] In the section where the width of the intermediate flow path of the cross-sectional area change member (131) decreases rapidly, the flow rate of the venting gas also changes rapidly. At the point where the flow rate of the venting gas changes rapidly and around the point where the flow rate changes rapidly, turbulence of the venting gas is generated, causing a large number of particles contained in the venting gas to settle into the inner surface of the cross-sectional area change member (131). Consequently, a large number of the particles made of combustible material contained in the venting gas cannot enter the second venting flow path (123) and settle into the inner surface of the cross-sectional area change member (131). This can contribute to preventing a fire from occurring outside the battery pack by minimizing or preventing the particles made of combustible material from leaking out to the outside of the battery pack.

[0097] In another embodiment of the present invention, the value of the inlet width (W1) is the maximum value among the values ​​of the width (W) of the intermediate flow path, the value of the outlet width (W3) is the minimum value among the values ​​of the width (W) of the intermediate flow path, and the value of the intermediate flow path width (W2) may have multiple values ​​within a range of less than or equal to the value of the inlet width (W1) and greater than or equal to the value of the outlet width (W3).

[0098] The intermediate channel may include a section where the value of the intermediate channel width (W2) is the same as the value of the inlet width (W1), a section where the value is the same as the value of the outlet width (W3), and a section where the value is different from the inlet width (W1) and the outlet width (W3).

[0099] In the section where the value of the intermediate flow path width (W2) is different from the value of the inlet width (W1) and the outlet width (W3), the intermediate flow path width (W2) may have multiple values. In the section where the value of the intermediate flow path width (W2) is different from the value of the inlet width (W1) and the outlet width (W3), the value of the intermediate flow path width (W2) may decrease linearly and gradually as it moves in the +X direction.

[0100] In another embodiment of the present invention, the value of the inlet width (W1) is the minimum value among the values ​​of the width (W) of the intermediate flow path, the value of the outlet width (W3) is the maximum value among the values ​​of the width (W) of the intermediate flow path, and the value of the intermediate flow path width (W2) may have multiple values ​​within a range greater than the value of the inlet width (W1) and less than or equal to the value of the outlet width (W3).

[0101] The intermediate channel may include a section where the value of the intermediate channel width (W2) is the same as the value of the inlet width (W1), a section where the value is the same as the value of the outlet width (W3), and a section where the value is different from the inlet width (W1) and the outlet width (W3).

[0102] In the section where the value of the intermediate flow path width (W2) is different from the value of the inlet width (W1) and the outlet width (W3), the intermediate flow path width (W2) may have multiple values. In the section where the value of the intermediate flow path width (W2) is different from the value of the inlet width (W1) and the outlet width (W3), the value of the intermediate flow path width (W2) may increase linearly and gradually as it moves in the +X direction.

[0103] In the section where the value of the intermediate flow path width (W2) increases linearly and gradually, the vortex of the venting gas can be minimized, and the settling of particles in this section can be minimized. In this case, the settling of particles can be relatively concentrated around the inlet (133) or outlet (135) of the cross-sectional area change member (131).

[0104] Therefore, when designing the shape of the first hollow (132) of the cross-sectional area change member (131), if these characteristics are taken into account, the sedimentation position of the particles can be set to an intended position. Thus, the shape of the first hollow (132) of the cross-sectional area change member (131) can be designed to be optimized for the characteristics of the venting gas, the characteristics of the particles contained in the venting gas, and the usage environment of the battery cell (121).

[0106] FIG. 5 is an enlarged view of area A of FIG. 2, showing a part of the battery cell (121) and a part of the busbar frame (142) according to another embodiment of the present invention.

[0107] As shown in FIG. 5, in another embodiment of the present invention, the busbar frame (142) may include a plurality of cell venting holes (143 in FIG. 2) spaced apart from each other in the Z-axis direction. A cross-sectional area changing member (131) may be inserted into each of the plurality of cell venting holes (143 in FIG. 2), and the outer surface of the cross-sectional area changing member (131) may be in close contact with the busbar frame (142).

[0108] According to this, the venting gas can be discharged more quickly into the second venting channel (123) compared to the case where a single cell venting hole (143 in FIG. 2) is provided. In addition, compared to the case where a single cell venting hole (143 in FIG. 2) is provided at the same point in the X-axis direction, a relatively large amount of particles can be prevented from being discharged into the second venting channel (123).

[0109] The width (W) of the first hollow (132) of the cross-sectional area change member (131) may have a single value, and the width (W) of the first hollow (132) may be constant in the X-axis direction. Accordingly, as the resistance to the inflow of the venting gas into the first hollow (132) increases, a significant number of particles contained in the venting gas may not flow into the first hollow (132) of the cross-sectional area change member (131) and may settle into the inner surface of the pack housing (110) immediately before the busbar frame (142).

[0111] FIG. 6 is an enlarged view of area A of FIG. 2, showing a part of the battery cell (121) and a part of the busbar frame (142) according to another embodiment of the present invention.

[0112] As shown in FIG. 6, in another embodiment of the present invention, the busbar frame (142) may include a plurality of cell venting holes (143 in FIG. 2) spaced apart from each other in the Z-axis direction. A cross-sectional area changing member (131) may be inserted into each of the plurality of cell venting holes (143 in FIG. 2), and the outer surface of the cross-sectional area changing member (131) may be in close contact with the busbar frame (142).

[0113] A plurality of cross-sectional area changing members (131) may exist at different heights on the Z-axis. The cross-sectional shapes of the first hollows (132) of the plurality of cross-sectional area changing members (131) may be the same or different from each other.

[0114] The width (W) of the first hollow (132) of the cross-sectional area change member (131) may have multiple values. The value of the inlet width (W1) of the first hollow (132) may be the maximum value among the values ​​of the width (W) of the first hollow (132), and the value of the outlet width (W3) may be the minimum value among the values ​​of the width (W) of the first hollow (132). The intermediate flow path may have multiple intermediate flow path widths (W2), and the multiple intermediate flow path widths (W2) may include values ​​different from the inlet width (W1) and outlet width (W3) within a range of less than the value of the inlet width (W1) and greater than the value of the outlet width (W3), while including the values ​​of the inlet width (W1) and outlet width (W3).

[0115] The intermediate channel may include a section where the value of the intermediate channel width (W2), which is the width, changes rapidly, and a section where it changes linearly and gradually. The resulting effect is the same as described above regarding whether a vortex is formed in the venting gas and the sedimentation pattern of particles according to the change in the flow velocity of the venting gas.

[0116] In one embodiment of the present invention, the value of the inlet width (W1) of the first hollow (132) may be the minimum value among the values ​​of the width (W) of the first hollow (132), and the value of the outlet width (W3) may be the maximum value among the values ​​of the width (W) of the first hollow (132). The intermediate flow path may have a plurality of intermediate flow path widths (W2), and the plurality of intermediate flow path widths (W2) may include values ​​other than the inlet width (W1) and outlet width (W3) within a range greater than the value of the inlet width (W1) and less than or equal to the value of the outlet width (W3), while including the values ​​of the inlet width (W1) and outlet width (W3).

[0117] The intermediate channel may include a section where the value of the intermediate channel width (W2), which is the width, changes rapidly, and a section where it changes linearly and gradually. The resulting effect is the same as described above regarding whether a vortex is formed in the venting gas and the sedimentation pattern of particles according to the change in the flow velocity of the venting gas.

[0118] In one embodiment of the present invention, the cross-sectional area changing member (131) may be provided with a material including an insulating material. According to this, the electrical stability of the battery pack can be improved.

[0119] In addition, in one embodiment of the present invention, the cross-sectional area changing member (131) may be provided with a material including a material having high thermal conductivity. Accordingly, cooling of the venting gas can be performed in the flow path of the venting gas. Thus, the cooling efficiency and safety of the battery pack can be improved.

[0120] In addition, in one embodiment of the present invention, the cross-sectional area changing member (131) may be provided with a material including an insulating material and a material with high thermal conductivity. The area of ​​the cross-sectional area changing member (131) adjacent to the battery cell (121) may be composed of an insulating material, and the area facing the first hollow (132) may be composed of a material with high thermal conductivity.

[0122] FIG. 7 is an enlarged view of area B of FIG. 2, showing a part of a battery cell (121) and a busbar frame (142) according to another embodiment of the present invention.

[0123] As shown in FIG. 7, a busbar frame (142) provided in the third pack unit (120c) and a busbar frame (142) provided in the fourth pack unit (120d) may come into contact with each other to form a second venting channel (123). The second venting channel (123) may exist in a certain section in the Y-axis (Y in FIG. 1) direction and may be connected to the first venting channel (112).

[0124] A plurality of busbar frames (142) can be brought into contact with each other such that the cell venting holes (143) provided in each frame face each other. Venting gas generated from the battery cell (121) can be introduced into the second venting passage (123) through the cell venting holes (143).

[0125] In one embodiment of the present invention, the height of the busbar frame (142) in the Z-axis direction in the thickness direction cross-section of the pack housing (110) may be higher than the height of the battery cell (121) in the Z-axis direction.

[0126] The busbar frame (142) may include a first protruding area (142b) which is an area protruding further in the +Z direction than the uppermost level in the Z-axis direction of the battery cell (121). The first protruding area (142b) may be located above the cell venting hole (143) in the +Z direction. The first protruding area (142b) may increase the cross-sectional area of ​​the second venting channel (123). When the cross-sectional area of ​​the second venting channel (123) is increased, the flow rate of the venting gas increases, allowing the venting gas to be quickly discharged to the outside of the pack housing (110).

[0127] The busbar frame (142) may have a length in the X-axis direction of the first protruding area (142b) that is shorter than the length in the X-axis direction of the area that is at the same height as the battery cell (121) in the Z-axis direction. Accordingly, the busbar frame (142) has a multi-stage shape in the thickness direction cross-section of the pack housing (110). The area having a multi-stage shape in the busbar frame (142) may be a multi-stage section (142c).

[0128] The above multi-stage section (142c) can change the height in the Z-axis direction of the second venting channel (123) connected to the cell venting hole (143). The above multi-stage section (142c) can make the height in the Z-axis direction of the second venting channel (123) lowest immediately after the cell venting hole (143) and highest at a position a certain distance away from the cell venting hole (143) in the X-axis direction, based on the cell venting hole (143) located on the left side of FIG. 7. Accordingly, the cross-sectional area of ​​the second venting channel (123) can be rapidly increased in the +X direction. Therefore, dust discharged into the cell venting hole (143) along with the venting gas can be settled in the second venting channel (123), and ignition caused by dust can be suppressed. This can be applied to the cell venting hole (143) located on the right side of FIG. 7 using the same principle.

[0130] FIG. 8 is an enlarged view of area B of FIG. 2, showing a part of a battery cell (121) and a busbar frame (142) according to another embodiment of the present invention.

[0131] As shown in FIG. 8, a unit cover member (151) may be provided on the upper side in the +Z direction of the battery cell (121). The unit cover member (151) may cover all battery cells (121) provided in one pack unit (120 in FIG. 1) and may be provided in a one-to-one correspondence with each pack unit (120 in FIG. 1). According to this, airtightness between each pack unit (120 in FIG. 1) is improved, so that the propagation or transfer of fire or flame from a pack unit (120 in FIG. 1) where a fire or flame has occurred to another pack unit (120 in FIG. 1) can be minimized or prevented.

[0132] A cover venting hole (151a) may be formed in the area of ​​the unit cover member (151) facing the cell venting hole (143). The cover venting hole (151a) is a hole formed in the unit cover member (151) and allows the venting gas generated from the battery cell (121) to flow smoothly into the cell venting hole (143).

[0133] A pack cover member (152) covering the unit cover member (151) and the busbar frame (142) may be provided on the upper side in the +Z direction of the unit cover member (151). The pack cover member (152) may include a second protruding area (152a) which is an area protruding in the direction of the busbar frame (142).

[0134] The second protruding area (152a) is an area protruding in the -Z direction from the surface of the pack cover member (152) facing the busbar frame (142), and may be provided with a shape corresponding to the first protruding area (142b) and the multi-stage portion (142c) of the busbar frame (142).

[0135] The protrusion height in the -Z direction of the second protrusion area (152a) may be at least the same as the protrusion height in the +Z direction of the first protrusion area (142b). Additionally, the second protrusion area (152a) may contact the unit cover member (151) and the busbar frame (142).

[0136] The pack cover member (152) presses the unit cover member (151), battery cell (121), and busbar frame (142) in the -Z direction, and in some cases, may be fixed to the pack housing (110) by a connecting member (not shown), such as a bolt.

[0137] According to such a pack cover member (152), the airtightness between a plurality of pack units (120 in FIG. 1) can be further improved, and the transfer of flame or fire between a plurality of pack units (120 in FIG. 1) can be minimized or prevented.

[0139] FIG. 9 is an enlarged view of area B of FIG. 2, showing a part of a battery cell (121) and a busbar frame (142) according to another embodiment of the present invention.

[0140] As shown in FIG. 9, in the thickness direction cross-section of the pack housing (110), the busbar frame (142) may have a first protruding area (142b) that includes a straight section (142d) and an inclined section (142e). The straight section (142d) may be parallel to the X-axis in the thickness direction cross-section of the pack housing (110) and may exist at the highest level in the Z-axis direction of the busbar frame (142). The inclined section (142e) extends to both sides of the straight section (142d) and may have a shape inclined at a certain angle with respect to the X-axis.

[0141] By having the first protruding area (142b) of the busbar frame (142) have this shape, the cross-sectional area of ​​the second venting channel (123) can be increased. Accordingly, dust ejected into the cell venting hole (143) along with the venting gas can be settled in the second venting channel (123), thereby suppressing ignition caused by dust.

[0143] FIG. 10 is an enlarged view of area B of FIG. 2, showing a part of a battery cell (121) and a busbar frame (142) according to another embodiment of the present invention.

[0144] As shown in FIG. 10, in the thickness direction cross-section of the pack housing (110), the busbar frame (142) may include a first protruding region (142b) and a curved portion (142f). The curved portion (142f) may be non-linearly inclined with respect to the X-axis in the thickness direction cross-section of the pack housing (110).

[0145] If the first protruding area (142b) of the busbar frame (142) has this shape, the cross-sectional area of ​​the second venting channel (123) can be increased. Accordingly, dust ejected into the cell venting hole (143) along with the venting gas can be settled in the second venting channel (123), thereby suppressing ignition caused by dust.

[0147] FIG. 11 is a cross-sectional view of a part of a battery pack according to another embodiment of the present invention. FIG. 11 is a view of the battery pack from a plan view, showing only the pack housing (110) of the battery pack in cross-section.

[0148] As shown in FIG. 11, the cross-sectional area changing member (131) may be provided in the first venting channel (112) and the second venting channel (123).

[0149] The cross-sectional area changing member (131) may include a first cross-sectional area changing member (136) in which the cross-sectional area of ​​the first hollow (132) changes in the direction of flow of the venting gas in the first hollow (132), and a second cross-sectional area changing member (137) in which the cross-sectional area of ​​the first hollow (132) is constant in the direction of flow of the venting gas in the first hollow (132).

[0150] In the first venting channel (112) and the second venting channel (123), a first cross-sectional area changing member (136) and a second cross-sectional area changing member (137) may be present.

[0151] In one embodiment of the present invention, the first cross-sectional area changing member (136) and the second cross-sectional area changing member (137) disposed in the first venting channel (112) may be spaced apart from each other by a certain distance.

[0152] In the first venting channel (112), the first cross-sectional area changing member (136) and the second cross-sectional area changing member (137) may be arranged alternately in the X-axis direction. Accordingly, the section where the cross-sectional area of ​​the venting gas channel changes is increased, allowing more particles contained in the venting gas to settle.

[0153] In one embodiment of the present invention, the first cross-sectional area changing member (136) may be provided in a divided form. The divided first cross-sectional area changing member (136) may be a pair of first cross-sectional area changing members (136). The length in the X-axis direction of the pair of first cross-sectional area changing members (136) may be the same as the length of the single second cross-sectional area changing member (137). This is a matter that can be applied to the first cross-sectional area changing member (136) by the same principle. According to this, the assembly of the cross-sectional area changing member may be improved, which may contribute to the improvement of the productivity of the battery pack. Each first hollow (132) of the divided first cross-sectional area changing member (136) may be mutually symmetrical with respect to the contact surface.

[0154] A plurality of first cross-sectional area changing members (136) may be provided in the second venting channel (123), and the first cross-sectional area changing members (136) may exist between the cell venting holes (143) in the Y-axis direction. The outer surface of the first cross-sectional area changing members (136) may be in close contact with the inner surface of the busbar frame (142). Although not shown in the drawing, a second cross-sectional area changing member (137) may exist between the first cross-sectional area changing members (136) in the second venting channel (123), or the second cross-sectional area changing member (137) may be substituted in place of the first cross-sectional area changing member (136). This is a matter that can be applied with various modifications considering the characteristics of the battery pack, the characteristics of the venting gas, etc.

[0155] In the second venting channel (123), the first hollow (132) of the first cross-sectional area change member (136) can be provided such that the width (W) in the X-axis direction changes in the Y-axis direction.

[0156] In the second venting channel (123), the value of the inlet width (W1) of the first hollow (132) of the first cross-sectional area changing member (136) may be smaller than the value of the outlet width (W3). The first hollow (132) of the first cross-sectional area changing member (136) present in the second venting channel (123) may be arranged in a direction parallel to the Y-axis. Additionally, the intermediate channel (134 in FIG. 4) of the first hollow (132) is also arranged in a direction parallel to the Y-axis, and the intermediate channel (134 in FIG. 4) may have a certain length in the Y-axis direction. Therefore, the intermediate channel width (W2), which is the width of the intermediate channel in the X-axis direction, may have multiple values ​​in the Y-axis direction. The intermediate channel width (W2) may have multiple values ​​within a range greater than the value of the inlet width (W1) and less than or equal to the value of the outlet width (W3).

[0157] According to this, as the venting gas passes through a section where the value of the width (W) of the first hollow (132) changes, the flow velocity changes, and thus sedimentation of particles contained in the venting gas occurs in the section where the flow velocity changes. Therefore, the discharge of particles to the outside of the pack housing (110) can be minimized or prevented.

[0158] The various shapes of the first hollow (132) shown in FIG. 11 are according to an embodiment of the present invention, and the first hollow (132) of the plurality of cross-sectional area changing members may have various shapes depending on the characteristics of the battery pack, etc. In addition, cross-sectional area changing members with various shapes of the first hollow (132) may be appropriately combined and used to suit the characteristics of the battery pack, etc.

[0159] In another embodiment of the present invention, a flashback prevention unit (160) may be provided at least one of the gas outlet (111), the first venting passage (112), the second venting passage (123), and the cell venting hole (143).

[0160] In one embodiment of the present invention, a flashback prevention unit (160) may be provided in the gas outlet (111). The flashback prevention unit (160) may be provided facing the gas outlet (111) and a portion of the first venting passage (112). The flashback prevention unit (160) may be in close contact with the pack housing (110) at the gas outlet (111) or the first venting passage (112).

[0161] In one embodiment of the present invention, the flashback prevention unit (160) may be provided with a porous flashback prevention member (161) including a plurality of holes.

[0162] In another embodiment of the present invention, the backfire prevention unit (160) may have the form of a mesh including a plurality of holes.

[0163] The flashback prevention member (161) may include a material with high thermal conductivity. Accordingly, it can absorb thermal energy from the venting gas or flame passing through the flashback prevention member (161). By cooling the flame or venting gas to below the ignition temperature through the flashback prevention member (161), it is possible to prevent a fire from occurring outside the pack housing (110) or the fire from spreading to the outside of the pack housing (110).

[0164] In addition, the flashback prevention member (161) installed in the gas outlet (111) can block fire or flames generated outside the pack housing (110) from entering the pack housing (110). Therefore, it is possible to minimize or prevent secondary damage caused by fire generated outside the battery pack in automobiles or energy storage systems from spreading into the interior of the battery pack.

[0165] In one embodiment of the present invention, the flashback prevention member (161) may be provided with a material comprising at least one of brass, bronze, copper, SUS, and aluminum. In addition, in one embodiment, the flashback prevention member (161) may include a fire-resistant material.

[0167] FIG. 12 is a cross-sectional view of a part of a battery pack according to another embodiment of the present invention. FIG. 12 is a view of the battery pack from a plan view, showing only the pack housing (110) of the battery pack in cross-section.

[0168] As shown in FIG. 12, the flashback prevention member (161) may also exist between a plurality of cross-sectional area change members in the first venting passage (112) or the second venting passage (123). By providing the flashback prevention member (161) between the cross-sectional area change members, the occurrence of fire inside the pack housing (110) can be minimized or prevented, and the propagation of fire or flame between each pack unit (120 in FIG. 1) can be minimized or prevented.

[0169] In this way, the position of the flashback prevention member (161) can be set by considering the flow of the venting gas, the temperature change of the venting gas, etc. In one embodiment of the present invention, the flashback prevention member (161) is provided at least one of the first venting passage (112), the second venting passage (123), the gas outlet (111), and the cell venting hole (143 in FIG. 11) to minimize or block the backflow of fire or flame.

[0171] FIG. 13 illustrates a cross-section of a first venting channel (112) equipped with a second cross-sectional area changing member (137). The details described below can be applied equally to the second venting channel (123). Flow in the second venting channel (123) can occur in the Y-axis (Y in FIG. 12) direction.

[0172] As shown in FIG. 13, the flow of venting gas in the first venting channel (112) can be in the +X direction. The first venting channel (112) may be provided with a plurality of second cross-sectional area changing members (137), and the plurality of second cross-sectional area changing members (137) may be spaced apart from each other by a certain distance. Venting gas may flow into the first hollow (132) of the second cross-sectional area changing member (137), and the width of the first hollow (132) in the Z-axis direction may be constant in the X-axis direction.

[0173] The venting gas undergoes a rapid reduction of the flow path just before entering the first hollow (132), and as the inflow resistance increases, a number of particles contained in the venting gas may settle to the bottom of the first venting flow path (112) at a position just before the second cross-sectional area change member (137).

[0174] The venting gas discharged to the outside of the second cross-sectional area change member (137) undergoes an expansion of the flow path and the flow velocity slows down. Therefore, a number of particles remaining in the venting gas can settle to the bottom of the first venting flow path (112) in the area immediately after the outlet (135 in FIG. 4) of the second cross-sectional area change member (137).

[0175] The venting gas, which continues to flow in the +X direction, encounters another second cross-sectional area change member (137) following in the +X direction and repeats the flow as described above. Therefore, whenever the venting gas passes through the second cross-sectional area change member (137), particles contained in the venting gas are filtered out step by step.

[0177] FIG. 14 illustrates a cross-section of a first venting channel (112) according to another embodiment of the present invention.

[0178] In the first venting channel (112), a first cross-sectional area changing member (136) may be arranged at a certain distance from each other. The value of the inlet width (W1) of the first cross-sectional area changing member (136) arranged in advance in the direction of flow of the venting gas may be smaller than the value of the outlet width (W3), and the value of the intermediate channel width (W2) of the intermediate channel may have multiple values ​​in the range of being greater than the value of the inlet width (W1) and less than or equal to the value of the outlet width (W3).

[0179] In one embodiment of the present invention, the intermediate flow path width (W2) of the first cross-sectional area change member (136) that precedes may include a value equal to the value of the inlet width (W1), a value equal to the value of the outlet width (W3), and any one value greater than the value of the inlet width (W1) and less than or equal to the value of the outlet width (W3). Accordingly, the intermediate flow path may include two sections where the width (W) increases rapidly.

[0180] The first cross-sectional area change member (136) following in the +X direction may be mutually symmetrical with respect to one plane parallel to the Z-axis with respect to the first cross-sectional area change member (136) preceding it.

[0181] According to this, a vortex of venting gas is generated in the section where the intermediate channel width (W2) changes rapidly, and additional sedimentation of particles (P) may occur in the area where the vortex is generated.

[0182] Therefore, sedimentation of particles (P) can be generated not only outside the first cross-sectional area change member (136) but also in the first hollow (132) of the first cross-sectional area change member (136).

[0184] FIG. 15 illustrates a cross-section of a first venting channel (112) according to another embodiment of the present invention.

[0185] As shown in FIG. 15, a first cross-sectional area changing member (136) and a second cross-sectional area changing member (137) may be spaced apart from each other in the first venting channel (112).

[0186] The first hollow (132) of the first cross-sectional area change member (136) may have an inlet width (W1) value that is the minimum value among the width (W) values ​​of the first hollow (132). In this case, the outlet width (W3) value may be the maximum value among the width (W) values ​​of the first hollow (132). At this time, the intermediate flow path width (W2) is the width value of the intermediate flow path (134 in FIG. 12), and may be the remaining values ​​among the width (W) values ​​of the first hollow (132) excluding the inlet width (W1) value and the outlet width (W3) value.

[0187] In one embodiment of the present invention, the intermediate channel (134 in FIG. 12) includes a section having a value equal to the value of the inlet width (W1) in the X-axis direction, and may include a section where the intermediate channel width (W2) expands beyond the value of the inlet width (W1) and a section having a value equal to the value of the outlet width (W3). In the section where the intermediate channel width (W2) expands beyond the value of the inlet width (W1), the value of the intermediate channel width (W2) may increase linearly. In the section where the intermediate channel width (W2) expands beyond the value of the inlet width (W1), the vortex of the venting gas is minimized, and the flow velocity of the venting gas slows down. Therefore, a large number of particles can be settled in the section where the flow velocity of the venting gas slows down.

[0188] A second cross-sectional area changing member (137) may be disposed at a position spaced a certain distance in the +X direction from the first cross-sectional area changing member (136). The second cross-sectional area changing member (137) may have a single value for the width of the first hollow (132), and the values ​​for the inlet width (W1), the intermediate flow path width (W2), and the outlet width (W3) of the first hollow (132) may be mutually identical.

[0189] As the venting gas flows into the first cross-sectional area changing member (136), its flow velocity changes, and it also changes while passing through the first hollow (132) of the first cross-sectional area changing member (136), and it can also change its flow velocity when discharged to the outside of the first cross-sectional area changing member (136). Therefore, while the flow velocity of the venting gas changes, particles contained in the venting gas can settle into the first venting passage (112) or the interior of the first cross-sectional area changing member (136).

[0190] Subsequently, the venting gas can be introduced into the second cross-sectional area changing member (137). As the venting gas is introduced into the second cross-sectional area changing member (137), the flow velocity changes, and the flow velocity remains constant in the first hollow (132) of the second cross-sectional area changing member (137), but can change as it is discharged to the outside of the second cross-sectional area changing member (137). Therefore, while the flow velocity of the venting gas is changing, particles contained in the venting gas can settle inside the first venting passage (112) or the second cross-sectional area changing member (137).

[0191] In this way, by alternately arranging the first cross-sectional area change member (136) and the second cross-sectional area change member (137) in the direction of flow of the venting gas, a rapid change in the flow velocity of the venting gas can be induced, and sedimentation of particles contained in the venting gas can be caused in the section of the venting gas flow velocity change. This can contribute to minimizing or preventing particles made of combustible material from being discharged to the outside of the pack housing (110).

[0193] FIG. 16 illustrates a cross-section of a first venting channel (112) according to another embodiment of the present invention.

[0194] As shown in FIG. 16, a first cross-sectional area changing member (136) and a second cross-sectional area changing member (137) may be spaced apart from each other in the first venting channel (112).

[0195] The first hollow (132) of the first cross-sectional area change member (136) may have an inlet width (W1) that is the maximum value among the width (W) values ​​of the first hollow (132). In this case, the outlet width (W3) may be the minimum value among the width (W) values ​​of the first hollow (132). At this time, the intermediate flow path width (W2) is the width value of the intermediate flow path (134 in FIG. 12), and may be the remaining values ​​among the width (W) values ​​of the first hollow (132) excluding the inlet width (W1) and the outlet width (W3).

[0196] In one embodiment of the present invention, the intermediate flow path (134 in FIG. 12) includes a section having a value equal to the value of the inlet width (W1) in the X-axis direction, and may include a section where the intermediate flow path width (W2) is reduced to less than the value of the inlet width (W1) and a section having a value equal to the value of the outlet width (W3). In the section where the intermediate flow path width (W2) is reduced to less than the value of the inlet width (W1), the value of the intermediate flow path width (W2) may decrease linearly. In the section where the value of the intermediate flow path width (W2) decreases linearly, the vortex of the venting gas is minimized and the flow velocity of the venting gas may increase. Therefore, the venting gas can be rapidly discharged to the outside of the first cross-sectional area change member (136).

[0197] A second cross-sectional area changing member (137) may be positioned at a certain distance in the +X direction from the first cross-sectional area changing member (136). The values ​​of the inlet width (W1), the intermediate flow path width (W2), and the outlet width (W3) of the second cross-sectional area changing member (137) may be mutually identical. Accordingly, the venting gas moves at a constant flow rate in the first hollow (132) of the second cross-sectional area changing member (137), and a certain amount of particles contained in the venting gas may settle in the first venting flow path (112) or the second cross-sectional area changing member (137).

[0198] If the first cross-sectional area changing member (136) and the second cross-sectional area changing member (137) are alternately arranged in the direction of flow of the venting gas, particles contained in the venting gas can be settled stepwise or gradually.

[0199] Accordingly, the characteristics of the venting gas and the characteristics of the particles are identified through the characteristics of the materials constituting the electrode (not shown), separator (not shown), and case of the battery cell (121), and the cross-sectional shape of the first hollow (132) of the first cross-sectional area change member (136) and the values ​​of the width (W) of the first hollow (132) of the first cross-sectional area change member (136) and the second cross-sectional area change member (137) can be determined by considering these characteristics.

[0201] FIG. 17 illustrates a cross-section of a first venting channel (112) according to another embodiment of the present invention.

[0202] As shown in FIG. 17, a plurality of first cross-sectional area changing members (136) may be arranged in the first venting channel (112) spaced apart from each other in the direction of venting gas flow.

[0203] The value of the inlet width (W1) of the first hollow (132) of the first cross-sectional area change member (136) may be the minimum value among the values ​​of the width (W) of the first hollow (132), and the value of the outlet width (W3) may be the maximum value among the values ​​of the width (W) of the first hollow (132). The intermediate flow path width (W2) may have multiple values, and the intermediate flow path width (W2) may include a value identical to the value of the inlet width (W1), a value identical to the value of the outlet width (W3), and a value different from the inlet width (W1) and the outlet width (W3).

[0204] In one embodiment of the present invention, the intermediate flow path (134 in FIG. 12) may have a value of intermediate flow path width (W2) that can change in the direction of venting gas flow, and the value of intermediate flow path width (W2) may increase in the direction of venting gas flow. The value of intermediate flow path width (W2) does not increase gradually in the direction of venting gas flow. The cross-section of the intermediate flow path (134 in FIG. 12) has a stepped shape and may include a multi-stage structure.

[0205] According to this, a vortex may be generated around the point where the intermediate flow path width (W2) changes rapidly in the first hollow (132), and the flow velocity may decrease rapidly around the point where the cross-sectional area of ​​the first hollow (132) increases rapidly. Therefore, an environment favorable for the particles (P) contained in the venting gas to settle is established, and a large number of particles (P) contained in the venting gas may settle in the first hollow (132) or the first venting flow path (112).

[0206] Another first cross-sectional area change member (136) arranged subsequently in the direction of venting gas flow with respect to the first cross-sectional area change member (136) may have an inlet width (W1) value that is the minimum value among the values ​​of the width (W) of the first hollow (132). In this case, the outlet width (W3) value may have the maximum value among the values ​​of the width (W) of the first hollow (132).

[0207] The intermediate channel width (W2) may have multiple values ​​and may include values ​​equal to the value of the inlet width (W1) and the value of the outlet width (W3). The intermediate channel (134 in FIG. 12) may include a section in which the value of its width increases linearly. In this case, the length in the X-axis direction of the section in the intermediate channel (134 in FIG. 12) having the same value as the value of the inlet width (W1) and the length in the X-axis direction of the section having the same value as the value of the outlet width (W3) may be longer than the length in the X-axis direction of the section in which the width changes.

[0208] The length in the X-axis direction of the section in the hollow where the value of the intermediate flow path width (W2) is equal to the value of the inlet width (W1), the length in the X-axis direction of the section in the first hollow (132) where the value of the intermediate flow path width (W2) is equal to the value of the outlet width (W3), and the length in the X-axis direction of the section in the first hollow (132) where the value of the intermediate flow path width (W2) is different from the value of the inlet width (W1) and the value of the outlet width (W3) are not necessarily limited by the present invention, and may be appropriately selected and applied considering the characteristics of the venting gas and the characteristics of the particles.

[0209] However, if the length in the X-axis direction of the section having the maximum value among the width (W) values ​​of the first hollow (132) is made relatively long, a wide section can be secured where particles (P) are settled as the venting gas flows. Therefore, if a large amount of particles (P) are to be settled inside the first cross-sectional area change member (136), the section where the width (W) value is the maximum value in the first hollow (132) can be configured to be relatively long.

[0211] FIG. 18 illustrates a cross-section of a first venting channel (112) according to another embodiment of the present invention.

[0212] As shown in FIG. 18, a plurality of first cross-sectional area changing members (136) may be arranged in the first venting channel (112) spaced apart from each other in the direction of venting gas flow, and the spacing distance between the first cross-sectional area changing members (136) may be appropriately selected and applied considering the characteristics of the venting gas, the characteristics of the particle (P), etc.

[0213] In one embodiment of the present invention, the value of the inlet width (W1) of the first cross-sectional area changing member (136) may be the maximum value among the values ​​of the width (W) of the first hollow (132), and the value of the outlet width (W3) may be the minimum value.

[0214] The intermediate flow path width (W2) may have multiple values, and the values ​​of the intermediate flow path width (W2) may include values ​​that are the same as the values ​​of the inlet width (W1) and the outlet width (W3), and values ​​that are different from the values ​​of the inlet width (W1) and the outlet width (W3).

[0215] Since the value of the outlet width (W3) of the first cross-sectional area change member (136) is smaller than the value of the width in the Z-axis direction of the first venting channel (112), the venting gas can be discharged to the outside of the first cross-sectional area change member (136), and the flow velocity can be rapidly slowed down. Therefore, a number of particles (P) can be settled at a point immediately in the X-axis direction of the first cross-sectional area change member (136).

[0216] The first cross-sectional area change member (136), which is positioned subsequently in the direction of venting gas flow, may have an inlet width (W1) that is the maximum value among the width (W) values ​​of the first hollow (132), and an outlet width (W3) that is the minimum value. Additionally, the value of the intermediate flow path width (W2) may decrease linearly as it moves in the +X direction.

[0217] As the venting gas flows from the first venting channel (112) into another first cross-sectional area change member (136), it can settle a number of particles (P) around the inlet of the other first cross-sectional area change member (136) due to the inflow resistance. Then, it flows into the first hollow (132), and as it moves in the +X direction from the first hollow (132), the flow velocity gradually increases, allowing it to be rapidly discharged to the outside of the first cross-sectional area change member (136).

[0218] In one embodiment of the present invention, a backfire prevention member (161) may be provided on the outer surface of the first cross-sectional area change member (136).

[0219] The flashback prevention member (161) may come into contact with the end of the pack housing (110) and the outer surface of the first cross-sectional area change member (136). At least a portion of the flashback prevention member (161) and at least a portion of the first cross-sectional area change member (136) may be aligned in the Z-axis direction. Accordingly, it is possible to prevent fire or flames from flowing backward into the first hollow (132) of the first cross-sectional area change member (136). This principle can also be applied to the second cross-sectional area change member (137 in FIG. 12).

[0222] The matters described above are described with respect to one embodiment of the present invention, and the scope of the present invention is not limited thereto. It will be obvious to those skilled in the art that various modifications and variations are possible within the scope of the technical concept of the present invention as described in the claims. Explanation of the symbols

[0224] 110 : Pack housing 111 : Gas vent 112: 1st venting channel 113: Connection port 120: Pack unit 121: Battery cell 122 : Electrode tab 123 : Second venting channel 124 : Pad 130 : Sedimentation Unit 131: Cross-sectional area change member 132: First hollow 133 : Entrance 134 : Intermediate Euro 135 : Exit 136 : First cross-sectional area change member 137 : Second cross-sectional area changing member 140 : Busbar unit 141 : Busbar missing 142 : Busbar frame 143 : Cell venting hole 151 : Unit cover member 152 : Pack cover component 160 : Backfire prevention unit 161 : Backfire prevention member

Claims

Claim 1 A battery pack comprising: a pack housing having a gas outlet and a venting channel connected to the gas outlet; a plurality of pack units each having at least one battery cell disposed in the pack housing and a busbar unit electrically connected to the battery cell; and a sedimentation unit provided in the venting channel and changing the cross-sectional area of ​​the venting channel to precipitate particles present in the venting gas; wherein the busbar unit includes a busbar member electrically connected to the battery cell; and a busbar frame supporting the busbar member; wherein the busbar frames of each of the plurality of adjacent pack units face and contact each other; and the venting channel includes a second venting channel facing the inner surface of each of the busbar frames of the plurality of adjacent pack units; and wherein the sedimentation unit changes the cross-sectional area of ​​the second venting channel to precipitate particles present in the venting gas into the second venting channel. Claim 2 A battery pack according to claim 1, wherein the sedimentation unit comprises a first hollow having a cross-sectional area narrower than the cross-sectional area of ​​the venting channel, and a cross-sectional area changing member through which venting gas flows into the first hollow. Claim 3 In paragraph 2, the busbar member is connected to the electrode tab of the battery cell, and the busbar unit further comprises at least one cell venting hole, and the venting passage further comprises a first venting passage formed inside the pack housing; and the second venting passage is formed between the plurality of mutually adjacent pack units or between the pack housing and the pack unit and is connected to the cell venting hole. Claim 4 In paragraph 3, the battery pack in which at least one cell venting hole is formed in the busbar frame. Claim 5 In claim 4, the cross-sectional area changing member is provided in the first venting channel, the second venting channel, and the cell venting hole, and the outer surface thereof is in close contact with the inner surface of the pack housing and the inner surface of the busbar frame. Claim 6 In claim 5, the first hollow of the cross-sectional area changing member is a battery pack in which the width changes in the direction of the flow of the venting gas in the cross-sectional area in the thickness direction of the pack housing. Claim 7 In claim 6, the first hollow of the cross-sectional area change member comprises an inlet, an intermediate flow path connected to the inlet, and an outlet connected to the intermediate flow path in the thickness direction cross-section of the pack housing, wherein the inlet width value, which is the width value of the inlet, is the minimum or maximum value of the width value of the first hollow, and the outlet width value, which is the width value of the outlet, has a value different from the inlet width value among the minimum value and the maximum value, and the intermediate flow path width value, which is the width value of the intermediate flow path, has a plurality of values. Claim 8 In claim 6, the first hollow of the cross-sectional area change member is a battery pack having a single width value in the thickness direction cross-section of the pack housing. Claim 9 In paragraph 4, the battery pack comprises a busbar frame having a first protruding area which is an area protruding above the uppermost level of the battery cell in the thickness direction cross-section of the pack housing. Claim 10 A battery pack according to claim 9, further comprising: a unit cover member covering the battery cell; and a pack cover member covering the unit cover member and the busbar frame. Claim 11 In claim 10, the busbar frame is multi-stage in the cross-section in the thickness direction of the pack housing, and the pack cover member includes a second protruding region which is a region protruding in the direction of the busbar frame; and the second protruding region is a battery pack that is in close contact with the unit cover member and the busbar frame. Claim 12 In item 10, the above-described busbar frame is a battery pack having a shape in the thickness direction cross-section of the above-described pack housing that includes at least one of a straight section, a curved section, and an inclined section. Claim 13 In claim 6, the cross-sectional area changing member comprises a first cross-sectional area changing member and a second cross-sectional area changing member arranged oppositely at at least one of the first venting channel, the second venting channel, and the cell venting hole, wherein the first cross-sectional area changing member has a plurality of values ​​for the width of the first hollow, and the second cross-sectional area changing member has a single value for the width of the first hollow. Claim 14 A battery pack further comprising, in any one of claims 3 to 13, a flashback prevention unit disposed at at least one of the gas outlet, the first venting passage, the second venting passage, and the cell venting hole. Claim 15 In claim 14, the above flashback prevention unit comprises a flashback prevention member having a plurality of holes; a battery pack.

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