Battery pack

Abstract

The technical concept of the present invention provides a battery pack comprising: a base frame; a cell assembly comprising a plurality of cell units stacked in a first direction and disposed on the base frame; and an upper frame disposed on the cell assembly and comprising a cooling channel configured to allow a cooling fluid to flow inside; wherein each of the plurality of cell units is arranged in a second direction perpendicular to the first direction and is connected to one another; and a cell frame that supports the plurality of battery cells and is in contact with the upper frame and the base frame.

Description

Technology Field

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

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries are widely used as energy sources for various wireless devices such as handsets, laptops, and cordless vacuum cleaners. Recently, as the manufacturing cost per unit capacity of secondary batteries has decreased dramatically due to improved energy density and economies of scale, and as the driving range of BEVs (battery electric vehicles) has increased to a level equivalent to that of fuel vehicles, the primary use of secondary batteries is shifting from mobile devices to mobility.

[0003] As rechargeable batteries are increasingly used in mobility, demands for their safety are rising. Given that accidents such as fires involving rechargeable batteries in mobility applications can endanger the lives of drivers, research into technologies to enhance battery safety is indispensable. Prior art literature

[0004] Republic of Korea Published Patent Application No. 10-2023-0170552 The problem to be solved

[0005] The problem that the technical concept of the present invention aims to solve is to provide a battery pack. means of solving the problem

[0006] To solve the above-mentioned problem, the technical concept of the present invention provides a battery pack comprising: a base frame; a cell assembly comprising a plurality of cell units stacked in a first direction and disposed on the base frame; and an upper frame disposed on the cell assembly and comprising a cooling channel configured to allow a cooling fluid to flow inside; wherein each of the plurality of cell units is arranged in a second direction perpendicular to the first direction and is connected to one another; and a cell frame that supports the plurality of battery cells and is in contact with the upper frame and the base frame.

[0007] In exemplary embodiments, the cell frame comprises: a support frame that supports the plurality of battery cells; and a plurality of heat transfer frames connected to the support frame and attached to the plurality of battery cells; wherein each of the plurality of heat transfer frames comprises an upper body connected to the upper frame and a lower body connected to the base frame.

[0008] In exemplary embodiments, the apparatus further comprises: a lower adhesive layer disposed between the base frame and the cell assembly and attaching the lower body of each of the plurality of heat transfer frames to the base frame; and an upper adhesive layer disposed between the upper frame and the cell assembly and attaching the upper body of each of the plurality of heat transfer frames to the upper frame.

[0009] In exemplary embodiments, the support frame includes a plurality of through holes into which the plurality of battery cells are inserted, and the plurality of heat transfer frames are connected to the support frame to cover the plurality of through holes of the support frame in the first direction.

[0010] In exemplary embodiments, the plurality of cell units each further comprises a plurality of pads attached to the plurality of battery cells, and the plurality of heat transfer frames each are attached to a first side of a corresponding battery cell among the plurality of battery cells, and the plurality of pads each are attached to a second side of a corresponding battery cell among the plurality of battery cells.

[0011] In exemplary embodiments, the cell assembly further comprises an internal busbar mounted on the cell frame and coupled to the electrode leads of the plurality of battery cells.

[0012] In exemplary embodiments, the cell assembly further comprises a busbar frame connected to the sides of the plurality of cell units, and the busbar frame supports a busbar connected to at least one electrode lead among the plurality of battery cells.

[0013] In exemplary embodiments, the base frame is characterized by including a cooling channel configured to allow a cooling fluid to flow inside.

[0014] In exemplary embodiments, the plurality of battery cells of the plurality of cell units are characterized by comprising two or more battery cells arranged along one side of the cell frame and two or more battery cells arranged along the other side of the cell frame.

[0015] In exemplary embodiments, the base frame comprises a bottom plate and a cooling plate disposed on the bottom plate and configured to have a cooling fluid flowing therein, wherein the cooling plate is a composite in which an upper plate in contact with the cell assembly and a lower plate in contact with the bottom plate are joined.

[0016] In exemplary embodiments, the cell frame is characterized by having a venting hole on the upper portion facing the upper frame.

[0017] In exemplary embodiments, the cell frame comprises: a support frame that supports the plurality of battery cells; and a plurality of heat transfer frames connected to the support frame and attached to the plurality of battery cells; wherein each of the plurality of heat transfer frames comprises an upper body connected to the upper frame and a lower body connected to the base frame, and the venting hole of the cell frame comprises a hole in the support frame and a hole in the upper body.

[0018] In exemplary embodiments, the cell frame is further characterized by including a fire-resistant film covering the venting hole.

[0019] In exemplary embodiments, the cell frame has a venting hole on its upper portion facing the base frame, and the base frame is characterized by including a venting channel configured to allow gas to flow inside, and a communication hole extending between the venting hole of the cell frame and the venting channel.

[0020] In exemplary embodiments, the cell frame comprises: a support frame that supports the plurality of battery cells; and a plurality of heat transfer frames connected to the support frame and attached to the plurality of battery cells; wherein each of the plurality of heat transfer frames comprises an upper body connected to the upper frame and a lower body connected to the base frame, and the venting hole of the cell frame comprises a hole in the support frame and a hole in the lower body. Effects of the invention

[0021] According to exemplary embodiments, the cell assembly may have a structure in which cell frames, each equipped with a plurality of battery cells, are stacked, thereby improving the rigidity of the cell assembly and the rigidity of the battery pack including the cell assembly.

[0022] According to exemplary embodiments, the upper and lower parts of the cell assembly are bonded to the base frame and the upper frame, respectively, so that the rigidity of the battery pack can be improved.

[0023] According to exemplary embodiments, battery cells included in a cell assembly can be thermally coupled to a base frame provided below the cell assembly and an upper frame provided above the cell assembly through the heat transfer frames of the cell frame. The battery pack has a dual cooling structure that cools the battery cells included in the cell assembly through the base frame and the upper frame, thereby improving the cooling performance for the battery cells.

[0024] The effects obtainable from the exemplary embodiments of the present invention are not limited to those mentioned above, and other unmentioned effects can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure belong from the following description. That is, unintended effects resulting from the implementation of the exemplary embodiments of the present disclosure can also be derived by those skilled in the art from the exemplary embodiments of the present disclosure. Brief explanation of the drawing

[0025] FIG. 1 is a perspective view showing a cell unit according to exemplary embodiments. FIG. 2 is a perspective view showing a cell unit according to exemplary embodiments. FIG. 3 is a front view showing a part of a cell unit according to exemplary embodiments. FIG. 4 is a perspective view showing a cell frame and an internal busbar according to exemplary embodiments. FIG. 5 is an exploded view showing a cell unit according to exemplary embodiments. FIG. 6 is a perspective view showing a cell assembly according to exemplary embodiments. FIG. 7 is a perspective view showing a part of a cell assembly according to exemplary embodiments. FIG. 8 is a perspective view showing a battery pack according to exemplary embodiments. FIG. 9 is a cross-sectional view showing a part of a battery pack according to exemplary embodiments. FIG. 10 is a cross-sectional view showing a part of a battery pack according to exemplary embodiments. FIG. 11 is a cross-sectional view showing a part of a battery pack according to exemplary embodiments. FIG. 12 is a cross-sectional view showing a cell unit according to exemplary embodiments. FIG. 13 is a cross-sectional view showing a battery pack according to exemplary embodiments. FIG. 14 is a cross-sectional view showing a part of a battery pack according to exemplary embodiments. FIG. 15 is a cross-sectional view showing a part of a battery pack according to exemplary embodiments. Specific details for implementing the invention

[0026] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings. Instead, based on the principle that the inventor can appropriately define the concepts of terms to best describe his invention, they should be interpreted in a meaning and concept consistent with the technical spirit of the present invention.

[0027] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0028] In addition, in describing the present invention, if it is determined that a detailed description of related known components or functions may obscure the essence of the invention, such detailed description is omitted.

[0029] Since embodiments of the present invention are provided to more fully explain the invention to those skilled in the art, the shapes and sizes of the components in the drawings may be exaggerated, omitted, or schematically depicted for clearer explanation. Accordingly, the size or proportion of each component does not entirely reflect the actual size or proportion.

[0031] (1st embodiment)

[0032] FIG. 1 is a perspective view showing a cell unit (100) according to exemplary embodiments. FIG. 2 is a perspective view showing a cell unit (100) according to exemplary embodiments. FIG. 1 and FIG. 2 are perspective views showing a cell unit (100) viewed from different directions. FIG. 3 is a front view showing a part of a cell unit (100) according to exemplary embodiments. FIG. 4 is a perspective view showing a cell frame (120) and an internal busbar (150) according to exemplary embodiments. FIG. 5 is an exploded view showing a cell unit (100) according to exemplary embodiments.

[0033] Referring to FIGS. 1 to 5, the cell unit (100) may include a plurality of battery cells (110), a cell frame (120), and an internal busbar (150).

[0034] A plurality of battery cells (110) may be mounted on a cell frame (120). A plurality of battery cells (110) may be arranged in a second horizontal direction (Y-axis direction) and may be electrically and physically connected to each other. In exemplary embodiments, a cell unit (100) may include two battery cells (110) arranged in the second horizontal direction (Y-axis direction) and connected in series with each other. In some exemplary embodiments, a cell unit (100) may include three or more battery cells (110) arranged in the second horizontal direction (Y-axis direction) and connected in series with each other. In some exemplary embodiments, a cell unit (100) may include two or more battery cells (110) placed on one side of the cell frame (120) and two or more battery cells (110) placed on the other side of the cell frame (120).

[0035] An individual battery cell (110) is a basic unit of a lithium-ion battery, i.e., a secondary battery. An individual battery cell (110) may include an electrode assembly, an electrolyte, and a cell case. The electrode assembly embedded in the cell case may include a positive electrode, a negative electrode, and a separator interposed between the positive and negative electrodes. Depending on the assembly form, the electrode assembly may be either a jelly-roll type or a stack type. A jelly-roll type electrode assembly may include a wound structure of a positive electrode, a negative electrode, and a separator interposed between them. A stack type electrode assembly may include a plurality of positive electrodes, a plurality of negative electrodes, and a plurality of separators interposed between them, which are stacked sequentially. The positive electrode may include a positive current collector and a positive active material. The negative electrode may include a negative current collector and a negative active material.

[0036] The individual battery cells (110) may correspond to pouch-type battery cells, cylindrical battery cells, or prismatic battery cells. In exemplary embodiments, the individual battery cells (110) may correspond to pouch-type battery cells. The electrode assembly of the pouch-type battery cells is placed within a case comprising an aluminum laminate sheet.

[0037] Each individual battery cell (110) may include an electrode assembly, a case housing the electrode assembly, and electrode leads (111, 112) connected to the electrode assembly. Each electrode lead (111, 112) may protrude from the case of the battery cell (110). Each individual battery cell (110) may extend in a second horizontal direction (Y-axis direction), and the electrode leads (111, 112) may be positioned at both ends of the individual battery cell (110).

[0038] The cell frame (120) can support a plurality of battery cells (110). The cell frame (120) may include a support frame (130) and a plurality of heat transfer frames (140).

[0039] A support frame (130) can support a plurality of battery cells (110). The support frame (130) may have a plurality of cell mounting areas, and each of the plurality of battery cells (110) may be mounted in each of the plurality of cell mounting areas of the support frame (130). The support frame (130) may include an electrically insulating material. For example, the support frame (130) may include plastic. For example, the support frame (130) may be manufactured through a plastic molding process.

[0040] The support frame (130) may include a lower rib (132), an upper rib (133), and a pair of side ribs (134). The lower rib (132) may correspond to the lower edge of the support frame (130) and may extend in the longitudinal direction of the support frame (130) (e.g., a second horizontal direction (Y-axis direction)). The lower rib (132) may face the lower surfaces of a plurality of battery cells (110). The upper rib (133) may correspond to the upper edge of the support frame (130) and may extend in the longitudinal direction of the support frame (130). The upper rib (133) may face the upper surfaces of a plurality of battery cells (110). A pair of side ribs (134) may be provided at both ends of the support frame (130). One of the pair of side ribs (134) may face a corresponding end among the plurality of battery cells (110) and may have a groove through which a corresponding electrode lead (111) among the plurality of battery cells (110) passes. The other of the pair of side ribs (134) may face a corresponding other end among the plurality of battery cells (110) and may have a groove through which a corresponding electrode lead (111) among the plurality of battery cells (110) passes.

[0041] The support frame (130) may include a plurality of through holes (131) spaced apart from each other along the longitudinal direction of the support frame (130). Each of the plurality of through holes (131) may penetrate the support frame (130) in a first horizontal direction (X-axis direction). Each of the plurality of cell mounting areas of the support frame (130) may include a single through hole (131). Each individual battery cell (110) may be inserted into a corresponding through hole (131) among the plurality of through holes (131) of the support frame (130).

[0042] A plurality of heat transfer frames (140) may be coupled to a support frame (130). For example, a plurality of heat transfer frames (140) may be coupled to the support frame (130) by a snap-fit, bolting, and / or adhesive. A plurality of heat transfer frames (140) may be coupled to the support frame (130) to cover a plurality of through holes (131) of the support frame (130) in a first horizontal direction (X-axis direction).

[0043] A plurality of heat transfer frames (140) may be attached to a plurality of battery cells (110). Each of the plurality of heat transfer frames (140) may be attached to a corresponding side of a plurality of battery cells (110) exposed through a plurality of through holes (131) of a support frame (130). For example, the plurality of heat transfer frames (140) may be attached to the plurality of battery cells (110) by an adhesive member such as tape or adhesive. The plurality of heat transfer frames (140) may be thermally coupled to the plurality of battery cells (110) and configured to transfer heat generated from the plurality of battery cells (110) to another structure. Heat generated from the plurality of battery cells (110) may be conducted to another structure through the plurality of heat transfer frames (140). Each individual heat transfer frame (140) may include a material with high thermal conductivity. For example, individual heat transfer frames (140) may include aluminum, copper, gold, silver, tungsten, iron, or a combination thereof. In some exemplary embodiments, a plurality of heat transfer frames (140) may be connected to each other to form a single heat transfer frame (140).

[0044] Each individual heat transfer frame (140) may include a central body (141) attached to a plurality of battery cells (110), a lower body (142) connected to the bottom of the central body (141), and an upper body (143) connected to the top of the central body (141). The central body (141) of the heat transfer frame (140) may have a plate shape extending in a second horizontal direction (Y-axis direction) and a vertical direction (Z-axis direction). The lower body (142) of the heat transfer frame (140) is located below the lower rib (132) of the support frame (130) and may contact the bottom surface of the lower rib (132) of the support frame (130). The lower body (142) of the heat transfer frame (140) may have a plate shape extending in a first horizontal direction (X-axis direction) and a second horizontal direction (Y-axis direction). The upper body (143) of the heat transfer frame (140) is positioned on the upper rib (133) of the support frame (130) and may come into contact with the upper surface of the upper rib (133) of the support frame (130). The upper body (143) of the heat transfer frame (140) may have a plate shape extending in a first horizontal direction (X-axis direction) and a second horizontal direction (Y-axis direction).

[0045] The inner busbar (150) can be mounted on the support frame (130) of the cell frame (120). More specifically, the inner busbar (150) can be mounted at the center along the longitudinal direction of the support frame (130). The inner busbar (150) can be coupled to the electrode leads (112) of adjacent battery cells (110). For example, the inner busbar (150) and the electrode leads (112) of the adjacent battery cell (110) can be coupled by welding. The inner busbar (150) and the electrode leads (112) of the adjacent battery cell (110) may have a plurality of welded areas (WR) formed during welding.

[0046] The cell unit (100) may further include a plurality of pads (160). The plurality of pads (160) may be attached to a plurality of battery cells (110). A first side of an individual battery cell (110) may be attached to a corresponding heat transfer frame (140) among a plurality of heat transfer frames (140), and a second side of an individual battery cell (110) may be attached to a corresponding pad (160) among a plurality of pads (160).

[0047] Each individual pad (160) may comprise a compressible material capable of varying thickness due to external force. For example, each individual pad (160) may comprise polyurethane, silicone, elastomer, or a combination thereof. Each individual pad (160) may absorb or mitigate external force acting due to swelling of the battery cells (110). Each individual pad (160) may be a thermal barrier. In exemplary embodiments, each individual pad (160) may have a high melting temperature and low thermal conductivity. In exemplary embodiments, each individual pad (160) may comprise a flame-retardant material, such as ceramic and coated glass material. In exemplary embodiments, each individual pad (160) may be configured to release a fire retarding material and a fire extinguishing agent in the event of a thermal runaway event of the battery cell (110).

[0048] In exemplary embodiments, to manufacture a cell unit (100), the steps of manufacturing a cell frame (120) by combining a plurality of heat transfer frames (140) with a support frame (130), mounting a plurality of battery cells (110) on the cell frame (120), welding electrode leads (112) of the plurality of battery cells (110), and attaching a plurality of pads (160) to the plurality of battery cells (110) may be performed in sequence.

[0050] (2nd Example)

[0051] FIG. 6 is a perspective view showing a cell assembly (200) according to exemplary embodiments. FIG. 7 is a perspective view showing a part of a cell assembly (200) according to exemplary embodiments.

[0052] Referring to FIGS. 6 and FIGS. 7 together with FIGS. 1 to 5, the cell assembly (200) may include a plurality of cell units (100), a pair of side covers (210), and a pair of end covers (230).

[0053] A plurality of cell units (100) may be arranged in a first horizontal direction (X-axis direction). A plurality of cell units (100) may be stacked in the first horizontal direction (X-axis direction) to form a stack (201). For example, the stack (201) may include several to tens of cell units (100) stacked in the first horizontal direction (X-axis direction).

[0054] Battery cells (110) provided in adjacent cell units (100) can be electrically connected. Cell frames (120) of adjacent cell units (100) can be joined together. Battery cells (110) provided in adjacent cell units (100) can be electrically connected by joining the electrode lead (111) of the battery cell (110) provided in one of the adjacent cell units (100) and the electrode lead (111) of the battery cell (110) provided in the other of the adjacent cell units (100). The joining between adjacent cell frames (120) can be achieved by joining the support frames (130) of the adjacent cell frames (120). For example, the support frames (130) can be joined by a snap-fit ​​and / or bolting connection. In the cell assembly (200), the lower bodies (142) of the heat transfer frames (140) provided in the cell units (100) may form the bottom surface of the cell assembly (200) and may be exposed to the outside. The lower bodies (142) of the heat transfer frames (140) provided in the cell units (100) may be arranged parallel to each other in a first horizontal direction (X-axis direction) and may be connected to each other. In the cell assembly (200), the upper bodies (143) of the heat transfer frames (140) provided in the cell units (100) may form the top surface of the cell assembly (200) and may be exposed to the outside. The upper bodies (143) of the heat transfer frames (140) provided in the cell units (100) may be arranged parallel to each other in a first horizontal direction (X-axis direction) and may be connected to each other.

[0055] A pair of side covers (210) may be spaced apart in a second horizontal direction (Y-axis direction) with the laminate (201) in between. One of the pair of side covers (210) may be connected to one side of each of the plurality of cell units (100), and the other of the pair of side covers (210) may be connected to the other side of each of the plurality of cell units (100).

[0056] A pair of side covers (210) may each include a busbar frame (211) and an outer cover (213) covering the busbar frame (211). The busbar frame (211) may support electrode leads (111) of a plurality of battery cells (110) provided in a plurality of cell units (100) and a plurality of busbars (220). The busbar frame (211) may include a plurality of slits into which the electrode leads (111) of the plurality of battery cells (110) are inserted. A plurality of busbars (220) may be mounted on the busbar frame (211). A plurality of busbars (220) may be coupled to at least one of the electrode leads (111) of the plurality of battery cells (110). A plurality of busbars (220) may include a terminal busbar protruding outside the cell assembly (200) and an interbusbar for connecting the battery cells (110) of adjacent cell units (100).

[0057] A pair of end covers (230) can be spaced apart in a first horizontal direction (X-axis direction) with the laminate (201) in between. One of the pair of end covers (230) can cover the front of the laminate (201), and the other of the pair of end covers (230) can cover the rear of the laminate (201).

[0058] In exemplary embodiments, to manufacture a cell assembly (200), the method may include the steps of manufacturing a laminate (201) by stacking a predetermined number of cell units (100), assembling side covers (210) on both sides of the laminate (201), and attaching end covers (230) to the front and rear sides of the laminate (201), respectively. The step of assembling side covers (210) on both sides of the laminate (201) may include performing welding between the electrode leads (111) of the battery cells (110) and the busbars (220).

[0060] (3rd Example)

[0061] FIG. 8 is a perspective view showing a battery pack (300) according to exemplary embodiments. FIG. 9 is a cross-sectional view showing a portion of a battery pack (300) according to exemplary embodiments. FIG. 10 is a cross-sectional view showing a portion of a battery pack (300) according to exemplary embodiments. FIG. 9 and FIG. 10 show different cross-sections of the battery pack (300).

[0062] Referring to FIGS. 8 to 10 together with FIGS. 1 to 7, the battery pack (300) may include a pack housing (301) and a cell assembly (200) mounted on the pack housing (301).

[0063] The pack housing (301) may provide an internal space for accommodating a cell assembly (200). The pack housing (301) may include a base frame (310), a side frame (320), and an upper frame (330).

[0064] The base frame (310) can support the cell assembly (200). The mounting surface of the base frame (310) can be in contact with the bottom surface of the cell assembly (200). The mounting surface of the base frame (310) can be extended in a first horizontal direction (X-axis direction) and a second horizontal direction (Y-axis direction). When viewed in a plane, the base frame (310) can have a roughly rectangular shape. For example, the base frame (310) can be manufactured through an extrusion process.

[0065] The base frame (310) may have a base cooling channel (311) configured to allow a cooling fluid supplied from the outside to flow. The base cooling channel (311) may overlap a plurality of cell units (100) in a vertical direction (Z-axis direction). For example, the base cooling channel (311) may extend in a first horizontal direction (X-axis direction) within the base frame (310). While the cooling fluid flows along the base cooling channel (311) of the base frame (310), cooling of a plurality of battery cells (110) of a plurality of cell units (100) may be achieved. The cooling fluid may include a coolant and / or a refrigerant.

[0066] A cell assembly (200) can be attached to a base frame (310) by a lower adhesive layer (341). The lower adhesive layer (341) is located between the cell assembly (200) and the base frame (310) and can be in contact with the lower bodies (142) of the heat transfer frames (140) of a plurality of cell units (100) and the mounting surface of the base frame (310). The lower adhesive layer (341) can thermally and physically bond the heat transfer frames (140) of a plurality of cell units (100) to the base frame (310). The battery cells (110) provided in the cell assembly (200) can each be thermally bonded to the base frame (310) through a heat conduction path comprising a corresponding heat transfer frame (140) and a lower adhesive layer (341). For example, the lower adhesive layer (341) may include a thermal resin and / or a thermal interface material (TIM).

[0067] The side frame (320) can be attached to the perimeter of the base frame (310). The side frame (320) can be extended along the perimeter of the base frame (310). The side frame (320) can be extended continuously along the perimeter of the base frame (310) to surround the cell assembly (200) mounted on the base frame (310). When viewed in a plane, the side frame (320) can have a roughly square ring shape.

[0068] The upper frame (330) may be attached to the upper part of the side frame (320) to cover the cell assembly (200). For example, the upper frame (330) may be bolted or welded to the side frame (320). The upper frame (330) may have a flat plate shape extending in a first horizontal direction (X-axis direction) and a second horizontal direction (Y-axis direction).

[0069] The upper frame (330) may have an upper cooling channel (331) configured to allow a cooling fluid supplied from the outside to flow. The upper cooling channel (331) may overlap a plurality of cell units (100) in a vertical direction (Z-axis direction). While the cooling fluid flows along the upper cooling channel (331) of the upper frame (330), cooling of a plurality of battery cells (110) of a plurality of cell units (100) may be achieved. The cooling fluid may include cooling water and / or a refrigerant. The upper cooling channel (331) of the upper frame (330) and the base cooling channel (311) of the base frame (310) may receive the cooling fluid through different paths.

[0070] In exemplary embodiments, the upper frame (330) may be manufactured by joining the lower plate and the upper plate. For example, the lower plate and the upper plate of the upper frame (330) may be joined by brazing. In exemplary embodiments, the upper plate and the lower plate may comprise different metals. For example, the upper plate may comprise copper, and the lower plate may comprise aluminum. When the lower plate and the upper plate of the upper frame (330) are joined, the cavity provided between the lower plate and the upper plate may form an upper cooling channel (331).

[0071] The cell assembly (200) can be attached to the upper frame (330) by an upper adhesive layer (343). The upper adhesive layer (343) is located between the cell assembly (200) and the upper frame (330), and the upper adhesive layer (343) can be in contact with the upper bodies (143) of the heat transfer frames (140) of the plurality of cell units (100) and the surface of the upper frame (330). The upper adhesive layer (343) can thermally and physically bond the heat transfer frames (140) of the plurality of cell units (100) to the upper frame (330). The battery cells (110) provided in the cell assembly (200) can each be thermally bonded to the upper frame (330) through a heat conduction path comprising the corresponding heat transfer frame (140) and the upper adhesive layer (343). For example, the upper adhesive layer (343) may include a thermal resin and / or a thermal interface material.

[0072] In exemplary embodiments, to manufacture a battery pack (300), the steps may include preparing a structure coupled to a base frame (310) and a side frame (320), applying a lower adhesive layer (341) on a mounting surface of the base frame (310), mounting a cell assembly (200) on the mounting surface of the base frame (310), applying an upper adhesive layer (343) on the upper surface of the cell assembly (200), and placing an upper frame (330) on the cell assembly (200).

[0073] According to exemplary embodiments, the cell assembly (200) may have a structure in which cell frames (120), each equipped with a plurality of battery cells (110), are stacked, thereby improving the rigidity of the cell assembly (200) and the rigidity of the battery pack (300) including the cell assembly (200).

[0074] According to exemplary embodiments, the upper and lower parts of the cell assembly (200) are bonded to the base frame (310) and the upper frame (330), respectively, so that the rigidity of the battery pack (300) can be improved.

[0075] According to exemplary embodiments, battery cells (110) included in a cell assembly (200) can be thermally coupled to a base frame (310) provided below the cell assembly (200) and an upper frame (330) provided above the cell assembly (200) through heat transfer frames (140) of a cell frame (120). The battery pack (300) has a dual cooling structure that cools the battery cells (110) included in the cell assembly (200) through the base frame (310) and the upper frame (330), thereby improving the cooling performance for the battery cells (110).

[0077] (Fourth Example)

[0078] FIG. 11 is a cross-sectional view showing a part of a battery pack (300A) according to exemplary embodiments. FIG. 12 is a cross-sectional view showing a cell unit (100A) according to exemplary embodiments. Hereinafter, a battery pack (300A) according to exemplary embodiments will be described with a focus on the differences from the battery pack (300) described with reference to FIG. 8 to 10.

[0079] Referring to FIGS. 11 and 12, the cell assembly (200) of the battery pack (300A) may include a plurality of cell units (100A). Each cell unit (100A) may include two or more battery cells (110) arranged along one side of the cell frame (120) and two or more battery cells (110) arranged along the other side of the cell frame. One side of the support frame (130A) may support two battery cells (110) arranged in a second horizontal direction (Y-axis direction), and the other side of the support frame (130A) may support two battery cells (110) arranged in a second horizontal direction (Y-axis direction). The electrode leads (112) of the battery cells (110) supported on one side of the support frame (130A) can be coupled to an internal busbar (150) mounted on one side of the support frame (130A). The electrode leads (112) of the battery cells (110) supported on the other side of the support frame (130A) can be coupled to an internal busbar (150) mounted on the other side of the support frame (130A).

[0080] The heat transfer frames (140A) of the cell frame (120A) may each include a central body (145), a lower body (146), and an upper body (147). The central body (145) may be in contact with a corresponding side of the battery cells (110) supported on one side of the support frame (130A) and a corresponding side of the battery cells (110) supported on the other side of the support frame (130A). A part of the lower body (146) may be between a corresponding one of the battery cells (110) supported on one side of the support frame (130A) and the base frame (310), and another part of the lower body (146) may be between a corresponding one of the battery cells (110) supported on the other side of the support frame (130A) and the base frame (310). A part of the upper body (147) may be located between the upper frame (330) and a corresponding one of the battery cells (110) supported on one side of the support frame (130A), and another part of the upper body (147) may be located between the upper frame (330) and a corresponding one of the battery cells (110) supported on the other side of the support frame (130A).

[0082] (5th Example)

[0083] FIG. 13 is a cross-sectional view showing a battery pack (300B) according to exemplary embodiments. Hereinafter, a battery pack (300B) according to exemplary embodiments will be described with a focus on the differences from the battery pack (300) described with reference to FIG. 8 to 10.

[0084] Referring to FIG. 13 together with FIGS. 1 to 7, in the pack housing (301A) of the battery pack (300B), the base frame (310A) may include a bottom plate (350) and a cooling plate (360).

[0085] The bottom plate (350) may have a flat plate shape extending in a first horizontal direction (X-axis direction) and a second horizontal direction (Y-axis direction). The bottom plate (350) may be attached to the side frame (320). For example, the bottom plate (350) may include plastic or metal.

[0086] A cooling plate (360) can be placed on a bottom plate (350) and can support a cell assembly (200). The cooling plate (360) can be attached to the heat transfer frames (140) of a plurality of cell units (100) by a lower adhesive layer (341). The cooling plate (360) may have a base cooling channel (369) configured to allow a cooling fluid to flow inside.

[0087] The cooling plate (360) may include an upper plate (361) and a lower plate (363) joined together. The upper plate (361) may be in contact with the cell assembly (200), and the lower plate (363) may be in contact with the bottom plate (350). In exemplary embodiments, the upper plate (361) and the lower plate (363) may be made of different metals. For example, the upper plate (361) may be made of aluminum, and the lower plate (363) may be made of copper. The perimeter of the upper plate (361) may be joined to the bottom plate (350) and / or the side frame (320). In exemplary embodiments, the upper plate (361), the bottom plate (350), and the side frame (320) may be bolted together and / or welded.

[0088] In exemplary embodiments, the cooling plate (360) may be a composite formed by joining a bottom plate (363) and a top plate (361). For example, the bottom plate (363) and the top plate (361) of the cooling plate (360) may be joined by brazing. When the bottom plate (363) and the top plate (361) of the cooling plate (360) are joined, the cavity provided between the bottom plate (363) and the top plate (361) may form a base cooling channel (369).

[0089] When the base frame (310A) is composed of a bottom plate (350) and a cooling plate (360) manufactured by brazing, the manufacturing cost of the base frame (310A) can be reduced compared to when the base frame (310A) is manufactured by extrusion.

[0091] (6th Example)

[0092] FIG. 14 is a cross-sectional view showing a portion of a battery pack (300C) according to exemplary embodiments. Hereinafter, a battery pack (300C) according to exemplary embodiments will be described with a focus on the differences from the battery pack (300C) described with reference to FIG. 8 to 10.

[0093] Referring to FIG. 14, in a battery pack (300C), each of a plurality of cell units (100B) may include a cell frame (120), and the cell frame (120) may include a venting hole (171) disposed in the cell frame (120) facing the upper frame (330). The venting hole (171) of the cell frame (120) may be configured to discharge gas generated from the battery cell (110) upward. The venting hole (171) of the cell frame (120) may include a venting hole (138) provided in the upper rib (133) of the support frame (130) and a venting hole (148) provided in the upper body (143) of the heat transfer frame (140). The venting hole (138) of the support frame (130) and the venting hole (148) of the upper body (143) can be aligned and connected in a vertical direction (Z-axis direction). In exemplary embodiments, the upper adhesive layer (343) can be applied to the cell frame (120) so as not to cover the venting hole (171) of the cell frame (120). In the event of thermal runaway of the battery cell (110), the gas generated from the battery cell (110) is discharged to the outside of the cell assembly (200) through the venting hole (171) of the cell frame (120) and can flow toward the exhaust port provided in the pack housing (301) through the passage formed between the cell assembly (200) and the upper frame (330). To ensure that the passage provided between the cell assembly (200) and the upper frame (330) has sufficient dimensions, the upper frame (330) defining the passage may have a structure such as a groove. The exhaust port of the pack housing (301) may be equipped with a venting device such as a relief valve or a burst valve.

[0094] In exemplary embodiments, individual cell units (100B) may further include a fireproof cover (191) covering a venting hole (171) of a cell frame (120). The fireproof cover (191) may be configured to rupture when a pressure exceeding a predetermined pressure is applied to the fireproof cover (191). When a battery cell (110) ignites, if the pressure of gas around the ignited battery cell (110) exceeds a predetermined pressure, the fireproof cover (191) around the ignited battery cell (110) may rupture and be discharged to the outside of the cell unit (100B) through the ruptured portion of the fireproof cover (191) and the venting hole (171) of the cell frame (120). In the case of a cell unit (100B) having a normal battery cell (110) that has not ignited, the venting hole (171) of the cell frame (120) is covered by a fireproof cover (191) so that high-temperature gas can be prevented from flowing into the normal battery cell (110) contained in the cell frame (120).

[0096] (7th Example)

[0097] FIG. 15 is a cross-sectional view showing a part of a battery pack (300D) according to exemplary embodiments. Hereinafter, a battery pack (300D) according to exemplary embodiments will be described with a focus on the differences from the battery pack (300) described with reference to FIG. 8 to 10.

[0098] Referring to FIG. 15, in a battery pack (300D), each of a plurality of cell units (100C) may include a cell frame (120), and the cell frame (120) may include a venting hole (173) in the lower portion facing the base frame (310). The venting hole (173) of the cell frame (120) may be configured to discharge gas generated from the battery cell (110) downward. The venting hole (173) of the cell frame (120) may include a venting hole (139) provided in the lower rib (132) of the support frame (130) and a venting hole (149) provided in the lower body (142) of the heat transfer frame (140). The venting hole (139) of the support frame (130) and the venting hole (149) of the lower body (142) may be aligned and connected in a vertical direction (Z-axis direction).

[0099] The base frame (310B) may include a venting channel (319) configured to allow gas to flow, and a communication hole (318) configured to transfer gas generated from the battery cell (110) to the venting channel (319). The venting channel (319) may extend within the base frame (310B) in a first horizontal direction (X-axis direction) and / or a second horizontal direction (Y-axis direction). The venting channel (319) may overlap each of the plurality of cell units (100C) in a vertical direction (Z-axis direction). The communication hole (318) may extend from the mounting surface of the base frame (310B) in contact with the cell assembly (200) to the venting channel (319). The communication hole (318) can communicate with the venting hole (173) of the cell frame (120) and can overlap with the venting hole (173) of the cell frame (120) in a vertical direction (Z-axis direction). Gas generated when the battery cell (110) ignites is introduced into the venting channel (319) of the base frame (310B) through the venting hole (173) of the cell frame (120) and the communication hole (318) of the base frame (310B), and can be discharged to the outside of the battery pack (300D) through the venting channel (319) of the base frame (310B).

[0100] In exemplary embodiments, individual cell units (100C) may further include a fireproof cover (193) covering the venting hole (173) of the cell frame (120). The fireproof cover (193) may be configured to rupture when a pressure exceeding a predetermined pressure is applied to the fireproof cover (193). When a battery cell (110) ignites, if the pressure of gas around the ignited battery cell (110) exceeds a predetermined pressure, the fireproof cover (193) around the ignited battery cell (110) may rupture and be discharged into the venting channel (319) of the base frame (310B) through the ruptured portion of the fireproof cover (193) and the venting hole (173) of the cell frame (120). In the case of a cell unit (100C) having a normal battery cell (110) that has not ignited, the venting hole (173) of the cell frame (120) is covered by a fireproof cover (193) so as to prevent high-temperature gas from flowing into the normal battery cell (110) contained in the cell frame (120).

[0101] In exemplary embodiments, the lower adhesive layer (341) may be applied to the mounting surface of the base frame (310B) so as not to cover the venting hole (173) of the cell frame (120) and / or the communication hole (318) of the base frame (310B). In the event of thermal runaway of the battery cell (110), the gas generated from the battery cell (110) may be discharged to the outside of the battery pack (300D) through the venting hole (173) of the cell frame (120) and the venting channel (319) of the base frame (310B).

[0103] The present invention has been described in more detail above through drawings and embodiments. However, the configurations described in the drawings or embodiments described in this specification are merely one embodiment of the present invention and do not represent all technical concepts of the present invention; therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application. Explanation of the symbols

[0104] 100: Cell unit 110: Battery cell 120: Cell Frame 130: Support Frame 140: Heat transfer frame 150: Internal busbar 160: Pad 200: Cell Assembly 210: Side cover 220: Busbar 230: End cover 300: Battery pack 301: Pack Housing 310: Base Frame 320: Side frame 330: Upper frame

Claims

Claim 1 A battery pack comprising: a base frame; a cell assembly comprising a plurality of cell units stacked in a first direction and disposed on the base frame; and an upper frame disposed on the cell assembly and comprising a cooling channel configured to allow a cooling fluid to flow inside; wherein each of the plurality of cell units comprises a plurality of battery cells connected to each other and arranged in a second direction perpendicular to the first direction; and a cell frame supporting the plurality of battery cells and in contact with the upper frame and the base frame. Claim 2 A battery pack according to claim 1, wherein the cell frame comprises: a support frame that supports the plurality of battery cells; and a plurality of heat transfer frames connected to the support frame and attached to the plurality of battery cells, wherein each of the plurality of heat transfer frames comprises an upper body connected to the upper frame and a lower body connected to the base frame. Claim 3 A battery pack according to claim 2, further comprising: a lower adhesive layer disposed between the base frame and the cell assembly and attaching the lower body of each of the plurality of heat transfer frames to the base frame; and an upper adhesive layer disposed between the upper frame and the cell assembly and attaching the upper body of each of the plurality of heat transfer frames to the upper frame. Claim 4 A battery pack according to claim 2, wherein the support frame includes a plurality of through holes into which the plurality of battery cells are inserted, and the plurality of heat transfer frames are connected to the support frame to cover the plurality of through holes of the support frame in the first direction. Claim 5 A battery pack according to claim 2, wherein the plurality of cell units each further comprises a plurality of pads attached to the plurality of battery cells, and the plurality of heat transfer frames each are attached to a first side of a corresponding battery cell among the plurality of battery cells, and the plurality of pads each are attached to a second side of a corresponding battery cell among the plurality of battery cells. Claim 6 A battery pack according to claim 1, wherein the cell assembly further comprises an internal busbar mounted on the cell frame and coupled to the electrode leads of the plurality of battery cells. Claim 7 A battery pack according to claim 1, wherein the cell assembly further comprises a busbar frame connected to the sides of the plurality of cell units, and the busbar frame supports a busbar connected to at least one electrode lead among the plurality of battery cells. Claim 8 A battery pack according to claim 1, wherein the base frame comprises a cooling channel configured to allow a cooling fluid to flow inside. Claim 9 A battery pack according to claim 1, wherein the plurality of battery cells of the plurality of cell units comprise two or more battery cells arranged along one side of the cell frame and two or more battery cells arranged along the other side of the cell frame. Claim 10 A battery pack according to claim 1, wherein the base frame comprises a bottom plate and a cooling plate disposed on the bottom plate and configured to have a cooling fluid flowing therein, and the cooling plate is a composite in which an upper plate in contact with the cell assembly and a lower plate in contact with the bottom plate are joined. Claim 11 A battery pack according to claim 1, wherein the cell frame has a venting hole on the upper portion facing the upper frame. Claim 12 A battery pack according to claim 11, wherein the cell frame comprises: a support frame that supports the plurality of battery cells; and a plurality of heat transfer frames connected to the support frame and attached to the plurality of battery cells; wherein each of the plurality of heat transfer frames comprises an upper body connected to the upper frame and a lower body connected to the base frame, and the venting hole of the cell frame comprises a hole in the support frame and a hole in the upper body. Claim 13 A battery pack according to claim 11, further comprising a fire-resistant film covering the venting hole of the cell frame. Claim 14 A battery pack according to claim 1, wherein the cell frame has a venting hole on its upper portion facing the base frame, and the base frame includes a venting channel configured to allow gas to flow inside, and a communication hole extending between the venting hole of the cell frame and the venting channel. Claim 15 A battery pack according to claim 14, wherein the cell frame comprises: a support frame that supports the plurality of battery cells; and a plurality of heat transfer frames connected to the support frame and attached to the plurality of battery cells; wherein each of the plurality of heat transfer frames comprises an upper body connected to the upper frame and a lower body connected to the base frame, and the venting hole of the cell frame comprises a hole in the support frame and a hole in the lower body.

Images