Battery device

Abstract

The present invention provides a battery device comprising: a base frame; a plurality of cell assemblies provided on the base frame and each including a plurality of battery cells; an inner frame provided on the base frame and disposed between the plurality of cell assemblies; a thermally conductive adhesive layer for attaching the plurality of cell assemblies to the base frame; and a first thermal barrier pad disposed between each of the plurality of cell assemblies and the inner frame and containing a first thermal foam material.

Description

Battery device

[0001] The present invention relates to a battery device.

[0002] This application claims the benefit of priority from Republic of Korea Patent Application No. 10-2024-0067704, filed May 24, 2024, and all contents of the document in that Republic of Korea Patent Application are incorporated herein by reference.

[0003] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. They are widely used as a power source for various wireless devices, including handsets, laptops, and cordless vacuum cleaners. Recently, improved energy density and economies of scale have dramatically reduced the per-unit manufacturing cost of secondary batteries. Furthermore, as the range of battery electric vehicles (BEVs) has increased to match that of fuel-powered vehicles, the primary use of secondary batteries is shifting from mobile devices to mobility.

[0004] As secondary batteries become increasingly used in mobility, demand for their safety is increasing. Fires and other accidents involving secondary batteries used in mobility vehicles can endanger the lives of drivers, making research into technologies that enhance secondary battery safety essential.

[0005] The technical problem to be solved by the present invention is to provide a battery device.

[0006] In order to solve the above-described problem, the technical idea of ​​the present invention provides a battery device including: a base frame; a plurality of cell assemblies provided on the base frame, each cell assemblies including a plurality of battery cells; an internal frame provided on the base frame and arranged between the plurality of cell assemblies; a thermally conductive adhesive layer attaching the plurality of cell assemblies to the base frame; and a first thermal barrier pad disposed between each of the plurality of cell assemblies and the internal frame, the first thermal barrier pad containing a first thermal foaming material.

[0007] In exemplary embodiments, a portion of the first thermal barrier pad is provided between the inner frame and the thermally conductive adhesive layer.

[0008] In exemplary embodiments, the first thermal barrier pad is characterized by being connected to the thermally conductive adhesive layer.

[0009] In exemplary embodiments, the invention further comprises a second thermal barrier pad disposed within the thermally conductive adhesive layer and containing a second thermal foam material.

[0010] In exemplary embodiments, the second thermal barrier pad is characterized by including a plurality of first holes filled with the thermally conductive adhesive layer.

[0011] In exemplary embodiments, the thermally conductive adhesive layer is characterized in that it is in direct contact with the base frame and the plurality of battery cells.

[0012] In exemplary embodiments, the second thermal barrier pad is characterized by having a mesh structure.

[0013] In exemplary embodiments, the second thermal barrier pad is characterized by including: a base layer including a plurality of second holes; and a thermal foam layer extending along the base layer and containing the second thermal foam material.

[0014] In exemplary embodiments, the base layer is characterized by having a mesh structure.

[0015] In exemplary embodiments, the first thermoplastic material is characterized by comprising expanded graphite.

[0016] In exemplary embodiments, the base frame is characterized by including cooling channels configured to allow cooling fluid to flow.

[0017] In exemplary embodiments, the device further comprises a top frame covering the plurality of cell assemblies, wherein the top frame is spaced apart from the plurality of cell assemblies with a venting space therebetween.

[0018] According to exemplary embodiments of the present invention, a battery device includes a thermal barrier pad containing a thermal foam material, thereby preventing or suppressing heat emitted from a cell assembly in which a thermal event has occurred from transferring to other cell assemblies through the frame. Since heat transfer between cell assemblies can be prevented or suppressed, the safety and reliability of the battery device can be improved.

[0019] The effects that can be obtained from the exemplary embodiments of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the exemplary embodiments of the present disclosure pertain from the following description. In other words, unintended effects resulting from practicing 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.

[0020] FIG. 1 is a cross-sectional view showing a battery device according to exemplary embodiments of the present invention.

[0021] Fig. 2 is a cross-sectional view of a battery device taken along line Ⅱ-Ⅱ' of Fig. 1.

[0022] Figure 3 is a cross-sectional view showing a battery device in which a thermal event has occurred.

[0023] FIG. 4 is a cross-sectional view showing a battery device according to exemplary embodiments of the present invention.

[0024] Fig. 5 is a cross-sectional view of the battery device taken along line V-V' of Fig. 4.

[0025] FIG. 6 is a cross-sectional view showing a battery device according to exemplary embodiments of the present invention.

[0026] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that aligns with the technical spirit of the present invention.

[0027] Accordingly, 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. Therefore, it should be understood that there may be various equivalents and modified examples that can replace them at the time of filing this application.

[0028] In addition, when describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description is omitted.

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

[0030]

[0031] (Example 1)

[0032] Fig. 1 is a cross-sectional view showing a battery device (10) according to exemplary embodiments of the present invention. Fig. 2 is a cross-sectional view of the battery device (10) taken along line II-II' of Fig. 1.

[0033] Referring to FIGS. 1 and 2, the battery device (10) may include a housing (500), a plurality of cell assemblies (100), a thermally conductive adhesive layer (210), and a first thermal barrier pad (310).

[0034] The housing (500) can provide an internal space that accommodates a plurality of cell assemblies (100). The housing (500) can include a base frame (510), a side frame (520), a top frame (530), and a plurality of internal frames (550).

[0035] The base frame (510) can support a plurality of cell assemblies (100). The base frame (510) can have a flat plate shape extending in a first horizontal direction (e.g., X direction) and a second horizontal direction (e.g., Y direction). The plurality of cell assemblies (100) can be arranged on the base frame (510) in a first horizontal direction (e.g., X direction) and a second horizontal direction (e.g., Y direction).

[0036] The base frame (510) may include a cooling channel (511) configured to allow a cooling fluid to flow. Cooling fluid supplied from the outside of the base frame (510) may be supplied to an inlet of the cooling channel (511), flow along the cooling channel (511), and discharged to the outside through an outlet of the cooling channel (511). While the cooling fluid flows along the cooling channel (511), cooling of the cell assembly (100) may be achieved. The cooling fluid may include coolant and / or refrigerant. The housing (500) may be equipped with a pipe configured to deliver the cooling fluid to the cooling channel (511) of the base frame (510). The cooling fluid supplied from the outside may be delivered to the cooling channel (511) of the base frame (510) through the pipe. In the present disclosure, the base frame (510) may be referred to as a cooling frame.

[0037] The side frame (520) can extend along the perimeter of the base frame (510) and surround the cell assembly (100).

[0038] A top frame (530) may be fastened to the side frames (520) to cover a plurality of cell assemblies (100). The top frame (530) may have a flat plate shape extending in a first horizontal direction (e.g., X direction) and a second horizontal direction (e.g., Y direction). The top frame (530) may be spaced apart from the plurality of cell assemblies (100) in a vertical direction (e.g., Z direction) with a venting space (540) therebetween.

[0039] A plurality of internal frames (550) can partition the internal space of the housing (500) into a plurality of accommodation spaces. The plurality of accommodation spaces defined by the plurality of internal frames (550) can be separated or partitioned from each other in a first horizontal direction (e.g., X-direction). One or more cell assemblies (100) can be arranged in each of the plurality of accommodation spaces of the housing (500) defined by the plurality of internal frames (550). In exemplary embodiments, the plurality of internal frames (550) can be spaced apart from each other in the first horizontal direction (e.g., X-direction), and each internal frame (550) can extend in a second horizontal direction (e.g., Y-direction). A single cell assembly (100) can be arranged between a pair of internal frames (550). A single internal frame (550) can be arranged between cell assemblies (100) that are adjacent in the first horizontal direction (e.g., X-direction). Each inner frame (550) can contact the side of the corresponding cell assembly (100).

[0040] The housing (500) may further include a center frame (560) extending in a first horizontal direction (e.g., X-direction) on the base frame (510). The center frame (560) may partition an internal space of the housing (500) into a plurality of spaces. The plurality of spaces defined by the center frame (560) may be separated or partitioned from each other in a second horizontal direction (e.g., Y-direction), and two or more cell assemblies (100) arranged in the first horizontal direction (e.g., X-direction) may be arranged in each of the plurality of spaces defined by the center frame (560).

[0041] The cell assembly (100) may be mounted on a base frame (510). The cell assembly (100) may include a plurality of battery cells (110). The cell assembly (100) may correspond to a battery module or a cell-to-pack structure.

[0042] 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 built into the cell case may include a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode. The electrode assembly may be either a jelly-roll type or a stack type depending on the assembly form. A jelly-roll type electrode assembly may include a winding structure of a positive electrode, a negative electrode, and a separator interposed therebetween. A stack type electrode assembly may include a plurality of sequentially stacked positive electrodes, a plurality of negative electrodes, and a plurality of separators interposed therebetween. The positive electrode may include a positive electrode current collector and a positive electrode active material. The negative electrode may include a negative electrode current collector and an negative electrode active material.

[0043] Each battery cell (110) may be a pouch-type battery cell, a cylindrical battery cell, or a square battery cell. The electrode assembly of the pouch-type battery cell is housed in a pouch case including an aluminum laminate sheet. The electrode assembly of the cylindrical battery cell is housed in a cylindrical metal can. The electrode assembly of the square battery cell is housed in a square metal can.

[0044] A plurality of battery cells (110) provided in the cell assembly (100) may be connected in series and / or in parallel. For example, the plurality of battery cells (110) may be connected in series with each other. For example, the plurality of battery cells (110) may also be connected in parallel with each other. For example, when a set of two or more battery cells (110) connected in parallel with each other is defined as a bank, one bank composed of two or more battery cells (110) connected in parallel with each other and another bank composed of two or more battery cells (110) connected in parallel with each other may be connected in series.

[0045] In exemplary embodiments, a plurality of battery cells (110) provided in a cell assembly (100) may be arranged in a first horizontal direction (e.g., X-direction), and individual battery cells (110) may extend in a second horizontal direction (e.g., Y-direction). An electrode lead may be provided at at least one of both ends of an individual battery cell (110) along the second horizontal direction (e.g., Y-direction). Electrode leads of neighboring battery cells (110) among the plurality of battery cells (110) may be electrically and physically connected to each other.

[0046] The cell assembly (100) may include a busbar frame connected to the side of a plurality of battery cells (110). A busbar frame may be arranged at each of the two ends of the cell assembly (100) along a second horizontal direction (e.g., Y direction). The busbar frame may support the busbars and the electrode leads of the battery cells (110). The busbars may be electrically and physically connected to at least one of the electrode leads of the plurality of battery cells (110). The busbar may be joined to at least one of the electrode leads of the plurality of battery cells (110) by welding.

[0047] A thermally conductive adhesive layer (210) may be interposed between each of the plurality of cell assemblies (100) and the base frame (510). A plurality of battery cells (110) provided in each of the plurality of cell assemblies (100) may be attached to the base frame (510) by the thermally conductive adhesive layer (210). An upper portion of the thermally conductive adhesive layer (210) may be in direct contact with each of the plurality of battery cells (110), and a lower portion of the thermally conductive adhesive layer (210) may be in direct contact with the base frame (510). The thermally conductive adhesive layer (210) may thermally couple each of the plurality of battery cells (110) to the base frame (510). The thermally conductive adhesive layer (210) may include a thermal resin and / or a thermal interface material.

[0048] A first thermal barrier pad (310) may be provided between each cell assembly (100) and each internal frame (550). The first thermal barrier pad (310) may prevent or suppress thermal propagation between each cell assembly (100) and its corresponding internal frame (550). For example, the cell assembly (100) may be disposed between a pair of internal frames (550), and the first thermal barrier pad (310) may be provided between each of the pair of internal frames (550) and the cell assembly (100). At least one side of the internal frame (550) may face the cell assembly (100), and the first thermal barrier pad (310) may extend along at least one side of the internal frame (550). The first thermal barrier pad (310) may contact a side of the corresponding cell assembly (100). In exemplary embodiments, a portion of the first thermal barrier pad (310) may be provided between the inner frame (550) and the thermally conductive adhesive layer (210). In exemplary embodiments, a portion of the first thermal barrier pad (310) may be connected to the thermally conductive adhesive layer (210).

[0049] The first thermal barrier pad (310) may include a thermal foam material. The thermal foam material of the first thermal barrier pad (310) may be configured to have fire resistance and to expand in volume above a specific temperature. When a thermal event, such as ignition and / or thermal runaway of a battery cell (110), occurs in the cell assembly (100), the thermal foam material of the first thermal barrier pad (310) expands, and the expanded thermal foam material may form an insulating layer (391) around the cell assembly (100) where the thermal event occurred. Heat transfer between the cell assembly (100) where the thermal event occurred and another cell assembly (100) and heat transfer between the cell assembly (100) where the thermal event occurred and the base frame (510) may be suppressed or blocked by the thermal insulation layer (391).

[0050] In exemplary embodiments, the thermal foam material of the first thermal barrier pad (310) may include expanded graphite, vermiculite, or a combination thereof. In exemplary embodiments, the first thermal barrier pad (310) may include a base layer and thermal foam particles within the base layer. The base layer may include a polymer and / or glass fiber, wherein the polymer may be made of polyurethane or silicone. The thermal foam particles may be particles or capsules comprising a thermal foam material.

[0051] In exemplary embodiments, the thermal foam material of the first thermal barrier pad (310) may be configured to expand between 10 and 50 times its volume when the foaming initiation temperature is exceeded. The foaming initiation temperature may be 100°C or higher, 200°C or higher, 300°C or higher, 400°C or higher, or 500°C or higher.

[0052] Figure 3 is a cross-sectional view showing a battery device (10) in which a thermal event has occurred.

[0053] Referring to FIG. 3, when a thermal event such as ignition of a battery cell (110) occurs in a cell assembly (100P), a thermal foam material expands in a first thermal barrier pad (310) around the cell assembly (100P) where the thermal event occurred, and the expanded thermal foam material can form an insulating layer (391) around the cell assembly (100P) where the thermal event occurred. More specifically, the thermal event can cause a thermally conductive adhesive layer (210) around the cell assembly (100) to be thermally deformed, thereby forming an empty space and / or cavity, and the empty space and / or cavity formed by the thermal deformation of the thermally conductive adhesive layer (210) can be filled with the expanded thermal foam material to form an insulating layer (391). Since heat transfer between the cell assembly (100P) where a thermal event has occurred and the base frame (510) is suppressed or blocked by the insulating layer (391), heat emitted from the cell assembly (100P) where a thermal event has occurred can be prevented or suppressed from being transferred to another cell assembly (100) via the base frame (510). Since heat transfer between cell assemblies (100) can be prevented or suppressed, the safety and reliability of the battery device (10) can be improved.

[0054] In addition, when a thermal event such as ignition of a battery cell (110) occurs in the cell assembly (100), high-temperature gas and / or flame generated from the cell assembly (100) may flow from the cell assembly (100) toward the top frame (530) and may flow laterally (e.g., in the X direction and / or Y direction) along the bottom surface of the top frame (530). Since an insulating layer (391) formed by expansion of a thermally expandable material is provided between the cell assembly (100) and the inner frame (550) and between the cell assembly (100) and the base frame (510), the high-temperature gas and / or flame generated from the cell assembly (100) may be vented upward where the insulating layer (391) is not provided, and thus, directional venting that vents the high-temperature gas and / or flame along an intended path may be enhanced.

[0055]

[0056] (Example 2)

[0057] Fig. 4 is a cross-sectional view illustrating a battery device (10A) according to exemplary embodiments of the present invention. Fig. 5 is a cross-sectional view of the battery device (10A) taken along line V-V' of Fig. 4. Hereinafter, the battery device (10A) of Figs. 4 and 5 will be described with a focus on differences from the battery device (10) described with reference to Figs. 1 and 2.

[0058] Referring to FIGS. 4 and 5, the battery device (10A) may include a second thermal barrier pad (330) provided within the thermally conductive adhesive layer (210). The second thermal barrier pad (330) may include a thermal foam material. The thermal foam material of the second thermal barrier pad (330) may be configured to have fire resistance and to expand in volume above a specific temperature. The thermal foam material of the second thermal barrier pad (330) may include expanded graphite, vermiculite, or a combination thereof. The thermal foam material of the second thermal barrier pad (330) may be substantially the same as or similar to the thermal foam material of the first thermal barrier pad (310). When a thermal event such as ignition and / or thermal runaway of a battery cell (110) occurs in the cell assembly (100), the thermal foam material of the second thermal barrier pad (330) expands, and the expanded thermal foam material can form an insulating layer (391) between the cell assembly (100) where the thermal event occurred and the base frame (510). Heat transfer between the cell assembly (100) where the thermal event occurred and the base frame (510) can be suppressed or blocked by the insulating layer (391).

[0059] The second thermal barrier pad (330) may have a mesh structure, a net structure, or a grid structure. The second thermal barrier pad (330) may include a plurality of holes (331). The plurality of holes (331) of the second thermal barrier pad (330) may be arranged in a first horizontal direction (e.g., X direction) and a second horizontal direction (e.g., Y direction). When viewed in a plan view, the plurality of holes (331) of the second thermal barrier pad (330) may be polygonal, such as circular or rectangular.

[0060] The thermally conductive adhesive layer (210) can fill the plurality of holes (331) of the second thermal barrier pad (330). When the thermal foaming material of the second thermal barrier pad (330) is not foamed, heat transfer between the base frame (510) and the plurality of battery cells (110) can be achieved through the thermally conductive adhesive layer (210) filling the plurality of holes (331) of the second thermal barrier pad (330).

[0061]

[0062] (Example 3)

[0063] Fig. 6 is a cross-sectional view illustrating a battery device according to exemplary embodiments of the present invention. Hereinafter, the battery device of Fig. 6 will be described with a focus on differences from the battery device (10A) described with reference to Figs. 4 and 5.

[0064] Referring to FIG. 6, in the battery device, the second thermal barrier pad (330A) may include a base layer (332) and a thermal foam layer (333).

[0065] The base layer (332) may have a mesh structure, a network structure, or a grid structure. The base layer (332) may include a plurality of holes (3321). The plurality of holes (3321) of the base layer (332) may be arranged in a first horizontal direction (e.g., X direction) and a second horizontal direction (e.g., Y direction). When viewed from a plan view, the plurality of holes (3321) of the base layer (332) may be polygonal, such as circular or rectangular. The base layer (332) may include an insulating material. For example, the base layer (332) may include plastic, but is not limited thereto.

[0066] The thermal foaming layer (333) may include a thermal foaming material. The thermal foaming layer (333) may conformally extend along the surface of the base layer (332). The thermal foaming layer (333) may be coated on the base layer (332) to have a uniform thickness. The base layer (332) may be covered by the thermal foaming layer (333) and not exposed to the outside. The thermal foaming layer (333) may be formed through a dipping process of dipping the base layer (332) into a solution containing the thermal foaming material or a spraying process of spraying the thermal foaming material onto the base layer (332), but the method of forming the thermal foaming layer (333) is not limited thereto.

[0067]

[0068] The present invention has been described in more detail through drawings and examples. However, the configurations described in the drawings or examples described in this specification are merely embodiments of the present invention and do not represent all of the technical ideas of the present invention. Therefore, it should be understood that various equivalents and modified examples may exist as of the time of this application.

Claims

1. Base frame; A plurality of cell assemblies provided on the base frame, each cell assembly including a plurality of battery cells; An internal frame provided on the base frame and arranged between the plurality of cell assemblies; a thermally conductive adhesive layer that attaches the plurality of cell assemblies to the base frame; and A first thermal barrier pad disposed between each of the plurality of cell assemblies and the inner frame, the first thermal barrier pad containing a first thermal foam material; A battery device comprising:

2. In paragraph 1, A battery device characterized in that a portion of the first thermal barrier pad is provided between the inner frame and the thermally conductive adhesive layer.

3. In paragraph 1, A battery device, characterized in that the first thermal barrier pad is connected to the thermally conductive adhesive layer.

4. In paragraph 1, A second thermal barrier pad disposed within the thermally conductive adhesive layer and containing a second thermal foaming material; A battery device characterized by further including:

5. In paragraph 4, A battery device, wherein the second thermal barrier pad comprises a plurality of first holes filled with the thermally conductive adhesive layer.

6. In paragraph 5, A battery device characterized in that the thermally conductive adhesive layer is in direct contact with the base frame and the plurality of battery cells.

7. In paragraph 4, A battery device characterized in that the second thermal barrier pad has a mesh structure.

8. In paragraph 4, The above second thermal barrier pad, a base layer comprising a plurality of second holes; and A thermal foam layer extending along the base layer and containing the second thermal foam material; A battery device characterized by including:

9. In paragraph 8, A battery device characterized in that the base layer has a mesh structure.

10. In paragraph 1, A battery device characterized in that the first thermal foaming material comprises expanded graphite.

11. In paragraph 1, A battery device characterized in that the base frame includes a cooling channel configured to allow cooling fluid to flow.

12. In paragraph 1, Further comprising a top frame covering the above plurality of cell assemblies, A battery device characterized in that the top frame is spaced apart from the plurality of cell assemblies with a venting space therebetween.

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