Battery cell assembly

Abstract

According to exemplary embodiments, a battery cell assembly is provided. The battery cell assembly comprises: a module frame including a bottom plate and side plates; multiple battery cells disposed on the module frame and arranged in a first direction parallel to the bottom plate; a top plate disposed on the multiple battery cells; and an external fireproof cover on the top plate, wherein the external fireproof cover is fastened to the module frame in a snap-fit manner.

Description

Battery cell assembly

[0001] The present invention relates to a battery cell assembly. The present application claims the benefit of Korean application No. 10-2024-0144820, filed on October 22, 2024, which is incorporated herein by reference in its entirety.

[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] The trend in the technological development of rechargeable batteries for mobility is the improvement of energy density and safety. The safety of rechargeable batteries is critical as it is directly linked to the lives of passengers. The safety of rechargeable batteries can be achieved through mechanical robustness, the reliability of electrical insulation, and the delay of heat transfer in the event of a thermal runaway event.

[0004] The problem that the technical concept of the present invention aims to solve is to provide a battery cell assembly with enhanced safety.

[0005] According to exemplary embodiments of the present invention for solving the above-described problem, a battery cell assembly is provided. The battery cell assembly comprises: a module frame including a bottom plate and side plates; a plurality of battery cells arranged on the module frame in a first direction parallel to the bottom plate; a top plate on the plurality of battery cells; and an external fireproof cover on the top plate, wherein the external fireproof cover is fastened to the module frame in a snap-fit ​​manner.

[0006] Each of the above side plates includes a plurality of snap pins protruding in the first direction.

[0007] Each of the above side plates includes an inner surface facing the plurality of battery cells and an outer surface opposite to the inner surface, and the plurality of snap pins are on the outer surface of each of the side plates.

[0008] The plurality of snap pins are spaced apart from each other in a second direction perpendicular to the first direction and parallel to the bottom plate.

[0009] Each of the above plurality of snap pins has a triangular prism shape.

[0010] Each of the above plurality of snap pins includes an inclined surface.

[0011] The height of each of the above plurality of snap pins in the first direction increases toward the bottom plate.

[0012] Each of the above plurality of snap pins has a cylindrical shape.

[0013] The above-mentioned external fireproof cover includes a top portion on the top plate and side portions connected to the top portion, and each of the side portions includes a plurality of fastening holes.

[0014] Each of the above multiple fastening holes has a rectangular shape.

[0015] Each of the above multiple fastening holes has a circular shape.

[0016] The plurality of fastening holes are spaced apart from each other in a second direction perpendicular to the first direction and parallel to the bottom plate.

[0017] The length of each of the plurality of side portions in the third direction perpendicular to the bottom plate is different from the length of each of the side plates in the third direction.

[0018] The length of the third direction perpendicular to the bottom plate of each of the plurality of side portions is shorter than the length of the third direction of each of the side plates.

[0019] The above external fireproof cover includes hard mica.

[0020] A battery cell assembly according to exemplary embodiments of the present invention may include an external fireproof cover having relatively high rigidity. Accordingly, the external fireproof cover can be snap-fitted to the side plates of a module frame, thereby improving the assemblability of the battery cell assembly. Additionally, since there is no adhesive between the module frame and the external fireproof cover, the external fireproof cover can be easily separated from the module frame.

[0021] 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.

[0022] FIG. 1 is a perspective view of a battery cell assembly according to exemplary embodiments.

[0023] FIG. 2 is a perspective view of a battery cell assembly according to exemplary embodiments.

[0024] FIG. 3 is an exploded perspective view of a battery cell assembly according to exemplary embodiments.

[0025] FIG. 4 is an exploded perspective view of a battery cell assembly according to exemplary embodiments.

[0026] FIG. 5 is a perspective view of a battery cell assembly according to exemplary embodiments.

[0027] FIG. 6 is a perspective view of a battery cell assembly according to exemplary embodiments.

[0028] FIG. 7 is an exploded perspective view of a battery cell assembly according to exemplary embodiments.

[0029] FIG. 8 is an exploded perspective view of a battery cell assembly according to exemplary embodiments.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034]

[0035] (1st embodiment)

[0036] FIG. 1 is a perspective view of a battery cell assembly (120) according to exemplary embodiments.

[0037] FIG. 2 is a perspective view of a battery cell assembly (120) according to exemplary embodiments.

[0038] FIG. 3 is an exploded perspective view of a battery cell assembly (120) according to exemplary embodiments.

[0039] FIG. 4 is an exploded perspective view of a battery cell assembly (120) according to exemplary embodiments.

[0040] Referring to FIGS. 1 to 4, the battery cell assembly (120) may further include a plurality of battery cells (121), resin layers (122), a first integrated circuit assembly (123), a second integrated circuit assembly (124), a Flat Flexible Cable (FFC) assembly (125), a module frame (126F), a top plate (126T), a first end plate assembly (127), a second end plate assembly (128), and an external fireproof cover (129).

[0041] Each of the plurality of battery cells (121) may be a lithium-ion battery. Each of the plurality of battery cells (121) includes an electrode assembly, an electrolyte, and a case. Each of the plurality of battery cells (121) may be any one of a cylindrical battery cell, a prismatic battery cell, and a pouch-type battery cell. The electrode assembly of the cylindrical battery cell is embedded in a cylindrical metal can. The electrode assembly of the prismatic battery cell is embedded in a prismatic metal can. The electrode assembly of the pouch-type battery cell is embedded in a pouch case containing an aluminum laminate sheet.

[0042] The electrode assembly may include an anode, a cathode, and a separator interposed between the anode and the cathode. 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 an anode, a cathode, and a separator interposed between them. A stack type electrode assembly may include a plurality of sequentially stacked anodes, a plurality of cathodes, and a plurality of separators interposed between them.

[0043] Each of the plurality of battery cells (121) may include a positive lead (121P) and a negative lead (121N). Each electrode assembly of the plurality of battery cells (121) may be connected to the positive lead (121P) and the negative lead (121N).

[0044] Multiple battery cells (121) may form multiple banks. Each of the multiple banks may include one or more battery cells (121). One or more battery cells (121) of each of the multiple banks may be connected in parallel with each other. Multiple banks may be connected in series with each other. Multiple banks may include a first bank, a last bank, and intermediate banks between them.

[0045] The positive leads (121P) of one or more battery cells (121) of the first bank can be short-circuited with the bus bar (123P). The positive leads (121P) of one or more battery cells (121) of the first bank can be welded with the bus bar (123P).

[0046] The negative leads (121N) of one or more battery cells (121) of the last bank may be short-circuited with the bus bar (123N). The negative leads (121N) of one or more battery cells (121) of the last bank may be welded with the bus bar (123N).

[0047] A plurality of battery cells (121) may be arranged in the X direction. A plurality of pads may be provided between the plurality of battery cells (121). The plurality of pads may horizontally press the plurality of battery cells (121) and prevent or mitigate swelling of the plurality of battery cells (121). The plurality of pads may isolate the plurality of battery cells (121) from one another. According to exemplary embodiments, each of the plurality of pads may include Polyurethane (PU). According to exemplary embodiments, each of the plurality of pads may include a refractory material.

[0048] According to exemplary embodiments, two or more banks may be interposed between adjacent pads. According to other exemplary embodiments, a plurality of pads may be arranged alternately with a plurality of banks.

[0049] The first integrated circuit assembly (123) and the second integrated circuit assembly (124) may be spaced apart in the Y direction with a plurality of battery cells (121) in between. The first integrated circuit assembly (123) and the second integrated circuit assembly (124) may be electrically connected by an FFC assembly (125). Accordingly, sensing values ​​(e.g., voltage, current, and / or temperature) of the integrated circuit (124C) may be transmitted to the integrated circuit (123C) through the FFC assembly (125).

[0050] The first integrated circuit assembly (123) may include an insulating frame (123F), an integrated circuit (123C), and bus bars (123P, 123I, 123N). The insulating frame (123F) may include an insulating material such as plastic. The insulating frame (123F) may cover the front of a plurality of battery cells (121). The insulating frame (123F) may support the integrated circuit (123C) and bus bars (123P, 123N, 123I).

[0051] The insulating frame (123F) may include rib structures, and accordingly, the insulating frame (123F) may be lightweight while simultaneously providing sufficient rigidity. The rib structures of the insulating frame (123F) may alternate with the lead supports of the insulating frame (123F). The lead supports of the insulating frame (123F) may overlap in the Y direction with the positive leads (121P) of the plurality of battery cells (121) and the negative leads (121N) of the plurality of battery cells (121). Slits may be interposed between the rib structures and the lead supports. The positive leads (121P) and the negative leads (121N) may pass through the slits. As the positive leads (121P) and the negative leads (121N) passing through the slits are welded together, the plurality of battery cells (121) and the insulating frame may be combined.

[0052] The bus bars (123P, 123N) may be external connection terminals of the battery cell assembly (120). The resulting voltage of a plurality of battery cells (121) may be output through the bus bars (123P, 123N). The bus bars (123P, 123N) may be fixed to an insulating frame.

[0053] The integrated circuit (123C) can be mounted on an insulating frame (123F). Positive leads (121P) and negative leads (121N) welded to each other can form nodes inside the battery cell assembly (120). The integrated circuit (123C) can be configured to measure the voltage of the nodes.

[0054] The second integrated circuit assembly (124) may include an insulating frame (124F), an integrated circuit (124C), and bus bars (124I). The insulating frame (124F) may include an insulating material such as plastic. The insulating frame (124F) may cover the rear of a plurality of battery cells (121). The insulating frame (124F) may support the integrated circuit (124C) and bus bars (123I).

[0055] The insulating frame (124F) may include rib structures, and accordingly, the insulating frame (124F) may be lightweight while simultaneously providing sufficient rigidity of the insulating frame (124F). The rib structures of the insulating frame (124F) may alternate with the lead supports of the insulating frame (124F). The lead supports of the insulating frame (124F) may overlap in the Y direction with the positive leads (121P) of the plurality of battery cells (121) and the negative leads (121N) of the plurality of battery cells (121). Slits may be interposed between the rib structures and the lead supports. The positive leads (121P) and the negative leads (121N) may pass through the slits. As the positive leads (121P) and the negative leads (121N) passing through the slits are welded together, the plurality of battery cells (121) and the insulating frame may be combined.

[0056] The integrated circuit (124C) can be mounted on an insulating frame (124F). Positive leads (121P) and negative leads (121N) welded to each other can form nodes inside the battery cell assembly (120). The integrated circuit (124C) can be configured to measure the voltage of the nodes.

[0057] The negative leads (121N) of one or more battery cells (121) of each intermediate bank may be short-circuited to the positive leads (121P) of one or more battery cells (121) of a subsequent bank through a corresponding bus bar (123I, 124I). The negative leads (121N) of one or more battery cells (121) of each intermediate bank and the positive leads (121P) of one or more battery cells (121) of a subsequent bank may be welded to a corresponding bus bar (123I, 124I).

[0058] The positive leads (121P) of one or more battery cells (121) of each of the intermediate banks may be short-circuited to the negative leads (121N) of one or more battery cells (121) of the preceding bank through a corresponding bus bar (123I, 124I). The positive leads (121P) of one or more battery cells (121) of each of the intermediate banks and the negative leads (121N) of one or more battery cells (121) of the preceding bank may be welded to a corresponding bus bar (123I, 124I).

[0059] According to exemplary embodiments, each of the bus bars (123I, 124I) may include a curved portion. According to exemplary embodiments, each of the bus bars (123I, 124I) may have a U-shape. According to exemplary embodiments, each of the bus bars (123I, 124I) may have a horseshoe shape.

[0060] The module frame (126) may have a roughly U-shaped form. The module frame (126) may include a bottom plate (126B) and side plates (126S). The bottom plate (126B) may be parallel to the X and Y directions. The bottom plate (126B) may be substantially perpendicular to the Z direction. The X, Y, and Z directions may be substantially perpendicular to each other. A plurality of battery cells (121) may be on the bottom plate (126B). The bottom plate (126B) may overlap the plurality of battery cells (121) in the Z direction.

[0061] Resin layers (122) may be located between the bottom plate (126B) and the plurality of battery cells (121). The resin layers (122) may mediate heat between the bottom plate (126B) and the plurality of battery cells (121). The resin layers (122) may be in contact with each of the bottom plate (126B) and the plurality of battery cells (121). The resin layers (122) may be a Thermal Interface Material (TIM). The plurality of battery cells (121) may be fixed to the bottom plate (126B) by the resin layers (122). The resin layers (122) may be a curable material.

[0062] Each of the side plates (126S) can be connected to the X-direction end of the bottom plate (126B). Each of the side plates (126S) can be substantially perpendicular to the bottom plate (126B). Each of the side plates (126S) can be substantially perpendicular to the X-direction.

[0063] Each of the side plates (126S) may include a plurality of snap pins (126SP) protruding from the outer surface (126SO) of each of the side plates (126S). Here, the inner surface (126SI) may face a plurality of battery cells (121), and the outer surface (126SO) may be opposite to the inner surface (126SI).

[0064] Multiple snap pins (126SP) may be spaced apart from each other in the Y direction. Multiple snap pins (126SP) may be arranged in the Y direction. Each of the multiple snap pins (126SP) may protrude in the X direction. Each of the multiple snap pins (126SP) may include an inclined surface. Each of the multiple snap pins (126SP) may have a roughly triangular prism shape. As it approaches the bottom plate (126B), the height of each of the multiple snap pins (126SP) in the X direction may increase.

[0065] When the outer fireproof cover (129) is fastened to the side plates (126S), the side portions (129S) of the outer fireproof cover (129) are spread out along the inclined surfaces of the plurality of snap pins (126SP), so that they can be easily inserted into the plurality of fastening holes (129SH). In addition, after the outer fireproof cover (129) and the side plates (126S) are fastened, the outer fireproof cover (129) and the side plates (126S) can be prevented from being easily separated.

[0066] The top plate (126T) may be spaced apart from the bottom plate (126B) with a plurality of battery cells (121) in between. The top plate (126T) may be welded to the side plates (126S). A person skilled in the art will be able to easily arrive at an embodiment in which the battery cell assembly comprises a monoframe in which the top plate (126T) and the module frame (126F) are integrated, based on what is described herein.

[0067] The top plate (126T) may include a plurality of exhaust holes (126TH). The shape and arrangement of each of the plurality of exhaust holes (126TH) are substantially the same as the shape and arrangement of the plurality of exhaust holes (129H). Accordingly, each of the plurality of exhaust holes (126TH) may overlap in the Z direction with a corresponding one of the plurality of exhaust holes (129H).

[0068] The first end plate assembly (127) may be adjacent to the first integrated circuit assembly (123). The distance between the first end plate assembly (127) and the first integrated circuit assembly (123) may be smaller than the distance between the first end plate assembly (127) and the second integrated circuit assembly (124).

[0069] The first end plate assembly (127) can cover the first integrated circuit assembly (123). The first end plate assembly (127) can overlap the first integrated circuit assembly (123) in the Y direction. The first end plate assembly (127) may include a first inner end plate (127I) and a first outer end plate (127O).

[0070] The first inner end plate (127I) may include slits (127S). Bus bars (123P, 123N) may be exposed outside the first end plate assembly (127) through the slits (127S), and accordingly, external connection through the bus bars (123P, 123N) may be provided. The first inner end plate (127I) may include an insulating material. The first inner end plate (127I) may prevent unwanted short circuits of the electrical elements of the first integrated circuit assembly (123).

[0071] The first outer end plate (127O) may comprise metal. Accordingly, the first outer end plate (127O) may provide sufficient rigidity for the protection of the first integrated circuit assembly (123). The first outer end plate (127O) may be welded to each of the bottom plate (126B), side plates (126S), and top plate (126T).

[0072]

[0073] The second end plate assembly (128) may be adjacent to the second integrated circuit assembly (124). The distance between the second end plate assembly (128) and the second integrated circuit assembly (124) may be smaller than the distance between the second end plate assembly (128) and the first integrated circuit assembly (123).

[0074] The second end plate assembly (128) can cover the second integrated circuit assembly (124). The second end plate assembly (128) can overlap the second integrated circuit assembly (124) in the Y direction. The second end plate assembly (128) may include a second inner end plate (128I) and a second outer end plate (128O).

[0075] The second inner end plate (128I) may include an insulating material. The second inner end plate (128I) can prevent unwanted short circuits of the electrical elements of the second integrated circuit assembly (124).

[0076] The second outer end plate (128O) may comprise metal. Accordingly, the second outer end plate (128O) may provide sufficient rigidity for the protection of the second integrated circuit assembly (124). The second outer end plate (128O) may be welded to each of the bottom plate (126B), side plates (126S), and top plate (126T).

[0077] The outer refractory cover (129) may include a refractory material. The outer refractory cover (129) may include a material having sufficient rigidity for snap-fit ​​fastening. The outer refractory cover (129) may include, for example, hard mica. The outer refractory cover (129) may have low thermal conductivity and a high ignition point.

[0078] The outer fireproof cover (129) may include a top section (129T) and side sections (129S) connected to the top section (129T). The top section (129T) may have a roughly flat shape. The top section (129T) may be substantially perpendicular to the Z direction. Each of the side sections (129S) may be substantially perpendicular to the X direction.

[0079] The top portion (129T) may be on the top plate (126T). The top portion (129T) may include a plurality of exhaust holes (129H). The length in the X direction of each of the plurality of exhaust holes (129H) may differ from the length in the X direction of each of the plurality of battery cells (121). The length in the X direction of each of the plurality of exhaust holes (129H) may be greater than the length in the X direction of each of the plurality of battery cells (121). Accordingly, each of the plurality of exhaust holes (129H) may expose two or more portions of the plurality of battery cells (121).

[0080] The length in the Y direction of each of the plurality of exhaust holes (129H) may differ from the length in the Y direction of each of the plurality of battery cells (121). The length in the Y direction of each of the plurality of exhaust holes (129H) may be shorter than the length in the Y direction of each of the plurality of battery cells (121). Accordingly, each of the plurality of battery cells (121) may overlap with two or more of the plurality of exhaust holes (129H) in the Z direction.

[0081] Each of the side sections (129S) may be connected to the X-direction end of the top section (129T). Each of the side sections (129S) may include a plurality of fastening holes (129SH). Each of the plurality of fastening holes (129SH) may have any shape that allows the insertion of a plurality of snap pins (126SP). For example, each of the plurality of fastening holes (129SH) may have a rectangular shape, but is not limited thereto. Each of the plurality of fastening holes (129SH) may be arranged in the Y direction. Each of the plurality of fastening holes (129SH) may be spaced apart from each other in the Y direction.

[0082] The height of each side section (129S) in the Z direction may differ from the height of each side plate (126S) in the Z direction. The height of each side section (129S) in the Z direction may be smaller than the height of each side plate (126S) in the Z direction. Accordingly, the side sections (129S) may partially cover the side plates (126S). The side sections (129S) may cover the upper portion of the side plates (126S).

[0083] According to exemplary embodiments, by providing an external fireproof cover (129) having high rigidity, the external fireproof cover (129) and the side plates (126S) can be fastened in a snap-fit ​​manner. Accordingly, the assembly of the external fireproof cover (129) can be improved, and since no adhesive is applied between the external fireproof cover (129) and the side plates (126S), rework is possible in the event of an issue during the manufacturing process. In addition, while adhesives generally melt at high temperatures, the external fireproof cover (129) and the side plates (126S) maintain a stable structure even at high temperatures, so that the external fireproof cover (129) can be prevented from detaching from the side plates (126S) in the event of a thermal runaway event.

[0084]

[0085] (2nd Example)

[0086] FIG. 5 is a perspective view of a battery cell assembly (120') according to exemplary embodiments.

[0087] FIG. 6 is a perspective view of a battery cell assembly (120') according to exemplary embodiments.

[0088] FIG. 7 is an exploded perspective view of a battery cell assembly (120') according to exemplary embodiments.

[0089] FIG. 8 is an exploded perspective view of a battery cell assembly (120') according to exemplary embodiments.

[0090] Referring to FIGS. 5 to 8, the battery cell assembly (120') may further include a plurality of battery cells (121), a first integrated circuit assembly (123), a second integrated circuit assembly (124), an FFC assembly (125), a module frame (126F'), a top plate (126T), a first end plate assembly (127), a second end plate assembly (128), and an external fireproof cover (129').

[0091] The plurality of battery cells (121), the first integrated circuit assembly (123), the second integrated circuit assembly (124), the FFC assembly (125), the top plate (126T), the first end plate assembly (127), and the second end plate assembly (128) are substantially the same as those described with reference to FIGS. 1 to 4, so a description of them is omitted.

[0092] The module frame (126F') is substantially the same as described with reference to FIGS. 1 through 4, except for the shape of the plurality of snap pins (126SP') on the side plates (126S). In this example, the plurality of snap pins (126SP') may have a cylindrical shape. The plurality of snap pins (126SP') are substantially the same as described with reference to FIGS. 1 through 4, except for the shape features.

[0093] The outer fireproof cover (129') is substantially the same as described with reference to FIGS. 1 to 4, except for the shape of the plurality of fastening holes (129SH') on the side portion (129S). Each of the plurality of fastening holes (129SH') may have a circular shape.

[0094] 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.

Claims

1. A modular frame including a bottom plate and side plates; A plurality of battery cells located on the module frame and arranged in a first direction parallel to the bottom plate; A top plate on the plurality of battery cells above; and Includes an external fireproof cover on the top plate, A battery cell assembly characterized in that the above-described external fireproof cover is fastened to the above-described module frame in a snap-fit ​​manner.

2. In Paragraph 1, A battery cell assembly characterized in that each of the above side plates includes a plurality of snap pins protruding in the first direction.

3. In Paragraph 2, Each of the above side plates includes an inner surface facing the plurality of battery cells and an outer surface opposite to the inner surface, and A battery cell assembly characterized in that the plurality of snap pins are located on the outer surface of each of the side plates.

4. In Paragraph 2, A battery cell assembly characterized in that the plurality of snap pins are spaced apart from each other in a second direction perpendicular to the first direction and parallel to the bottom plate.

5. In Paragraph 2, A battery cell assembly characterized in that each of the above plurality of snap pins has a triangular prism shape.

6. In Paragraph 2, A battery cell assembly characterized in that each of the above plurality of snap pins includes an inclined surface.

7. In Paragraph 2, A battery cell assembly characterized in that the height of each of the plurality of snap pins in the first direction increases toward the bottom plate.

8. In Paragraph 2, Each of the above plurality of snap pins is a battery cell assembly having a cylindrical shape.

9. In Paragraph 1, The above external fireproof cover includes a top portion on the top plate and side portions connected to the top portion, and A battery cell assembly characterized in that each of the above-mentioned side parts includes a plurality of fastening holes.

10. In Paragraph 9, A battery cell assembly characterized in that each of the above plurality of fastening holes has a rectangular shape.

11. In Paragraph 9, A battery cell assembly characterized in that each of the above plurality of fastening holes has a circular shape.

12. In Paragraph 9, A battery cell assembly characterized in that the plurality of fastening holes are spaced apart from each other in a second direction perpendicular to the first direction and parallel to the bottom plate.

13. In Paragraph 9, A battery cell assembly characterized in that the length of each of the plurality of side portions in a third direction perpendicular to the bottom plate is different from the length of each of the side plates in the third direction.

14. In Paragraph 9, A battery cell assembly characterized in that the length of each of the plurality of side portions in a third direction perpendicular to the bottom plate is shorter than the length of each of the side plates in the third direction.

15. In Paragraph 1, A battery cell assembly characterized by the above-mentioned external fireproof cover including hard mica.

Images