Method for manufacturing battery pack

Abstract

The present invention relates to a method for manufacturing a battery pack, the method comprising: a first step of coupling a main case and a first case by inserting the first case in a sliding manner toward a first direction into the main case having at least a portion of both side surfaces open toward the first direction and a second direction opposite to the first direction, wherein a pack case comprises the main case, the first case, and a second case; a second step of coupling a BMS assembly electrically connected to a battery cell assembly to the battery cell assembly; a third step of inserting the battery cell assembly into the main case in a sliding manner toward the first direction such that one surface of the battery cell assembly faces one surface of the first case; and a fourth step of coupling the main case and the second case such that one surface of the battery cell assembly faces one surface of the second case.

Description

Battery pack manufacturing method

[0001] The present invention relates to a method for manufacturing a battery pack, and more particularly, to a method for manufacturing a battery pack with an improved pack case.

[0002] Secondary batteries, which are highly applicable across product groups and possess electrical characteristics such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are powered by electrical power sources. These secondary batteries are attracting attention as a new energy source for environmental friendliness and energy efficiency, not only because they can drastically reduce the use of fossil fuels, but also because they produce no byproducts from energy use. Furthermore, recent global trends show that demand for small electric vehicles (LEVs, Light Electric Vehicles) is rapidly increasing due to growing interest in eco-friendly, short-distance transportation to minimize carbon dioxide emissions caused by global warming, and this is leading to a corresponding increase in demand for secondary batteries.

[0003] Commonly used secondary batteries today include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. When high output voltage is required, multiple battery cells are connected in series to form a battery module or battery pack. Furthermore, to increase charge / discharge capacity, multiple battery cells are connected in parallel to form a battery module or pack. Therefore, the number of battery cells included in a battery module or pack can vary depending on the required output voltage or charge / discharge capacity.

[0004] Recently, secondary batteries have been widely used for powering and storing energy not only in small devices such as portable electronic devices, but also in medium- to large-sized devices such as electric bikes, electric vehicles, and home or industrial energy storage systems (ESS). Specifically, when multiple secondary batteries constitute a single battery pack, they may be grouped into multiple groups, such as cell module assemblies, and then included in the battery pack.

[0005] Fig. 1 is a perspective view schematically showing a part of a conventional battery pack configuration, and Fig. 2 is a cross-sectional configuration diagram taken along line A1-A1' of Fig. 1.

[0006] Referring to FIGS. 1 and 2, two cell module assemblies (10) are included inside a pack case (20). Each cell module assembly (10) includes a plurality of battery cells (11), such as cylindrical batteries. At this time, each battery cell (11) has a positive terminal (+) and a negative terminal (-) positioned at both ends, and can be stacked in a vertical direction (Z-axis direction) while lying horizontally so that the positive terminals and negative terminals are positioned at both ends in the horizontal direction (X-axis direction).

[0007] In particular, adjacent battery cells (11) in one cell module assembly (10) may be configured to be electrically connected in series by connecting the positive and negative terminals to each other. At this time, the electrical connection between the two battery cells (11) may be implemented by a method such as spot welding a bus bar in the form of a metal plate to the positive terminal and / or the negative terminal. However, in this implementation method, for the convenience of electrical connection, as illustrated in FIG. 2, multiple battery cells (11) in one cell module assembly (10) may be arranged in a form in which the positions of the positive and negative terminals are staggered. In addition, due to this configuration, a structure in which the positive and negative terminals face each other may be created between the two cell module assemblies (10), as indicated by A2 in FIG. 2.

[0008] However, according to the conventional battery pack configuration, since the pack case (20) is assembled after electrical connection and BMS (battery management system) connection between two cell module assemblies (10), it is impossible to implement CTP (Cell To Pack), and since a heat dissipation pad (e.g., thermal interface material; TIM) is placed between the cell module assembly (10) and the pack case (20), direct heat conduction does not occur when internal heat moves from the cell module assembly (10) to the pack case (20), so there is a problem that heat dissipation loss occurs during the heat conduction process and material costs increase.

[0009]

[0010] The present invention was created under the background of the above-described prior art, and its purpose is to provide a method for manufacturing a battery pack capable of directly transmitting heat generated by charging and discharging a plurality of battery cell assemblies to a pack case, thereby effectively increasing the cooling efficiency and / or heat transfer efficiency of the battery pack, and a battery pack manufactured by the method.

[0011] Another technical challenge of the present invention is to provide a method for manufacturing a battery pack that improves manufacturing efficiency and facilitates assembly by sequentially stacking components of the battery pack in one direction.

[0012] The technical problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below.

[0013]

[0014] To solve the above problem, the present invention can provide a battery pack including a pack case and a battery cell assembly configured to be accommodated inside the pack case, wherein at least one side of the battery cell assembly is configured to directly face at least one side of the pack case.

[0015] The battery cell assembly may include a first cell assembly including a plurality of first battery cells and a first cell frame accommodating the plurality of first battery cells, and a second cell assembly disposed in a stacked manner with the first cell assembly and including a plurality of second battery cells and a second cell frame accommodating the plurality of second battery cells.

[0016] The first cell assembly and the second cell assembly may be spaced apart from each other, and the electrode terminals of the plurality of first battery cells and the electrode terminals of the plurality of second battery cells may be configured to face each other.

[0017] The above battery cell assembly may further include a screen member disposed between the first cell assembly and the second cell assembly.

[0018] The electrode terminals of the plurality of first battery cells and the plurality of second battery cells may be arranged in the central portion of the pack case.

[0019] The battery may further include a first plate-shaped bus bar for connecting the plurality of first battery cells to each other on the electrode terminals of the plurality of first battery cells, a second plate-shaped bus bar for connecting the plurality of second battery cells to each other on the electrode terminals of the plurality of second battery cells, and an inter-bus bar for connecting the first plate-shaped bus bar and the second plate-shaped bus bar.

[0020] The pack case may include a main case configured to surround the battery cell assembly, which is configured to have a hollow shape in which at least a portion of both sides facing a first direction and a second direction opposite to the first direction are open, a first case covering a first opening of the main case facing the first direction, and a second case covering a second opening of the main case facing the second direction.

[0021] The first case may cover the first opening from the inside of the main case, and the second case may cover the second opening from the outside of the main case.

[0022] The size of the above first case may be smaller than the size of the above second case.

[0023] The first case and the second case are each metal plates, and the plurality of first battery cells can directly transfer heat to the first case, and the plurality of second battery cells can directly transfer heat to the second case.

[0024] The main case may further include a plurality of side walls and a cover side wall extending vertically from one end of the first direction of the plurality of side walls.

[0025] One side of the first cell assembly may be arranged to be in contact with one side of the first case, and one side of the second cell assembly may be arranged to be in contact with one side of the second case.

[0026] The first cell frame may include at least one first receiving groove through which electrode terminals of the plurality of first battery cells are exposed and at least one first hole for exposing bottom surfaces of the plurality of first battery cells opposite the electrode terminals of the plurality of first battery cells, and the second cell frame may include at least one second receiving groove through which electrode terminals of the plurality of second battery cells are exposed and at least one second hole for exposing bottom surfaces of the plurality of second battery cells opposite the electrode terminals of the plurality of second battery cells.

[0027] The BMS assembly may further include a BMS assembly arranged so that one end is in contact with the first cell assembly and the other end is in contact with the second cell assembly.

[0028] The plurality of first battery cells and the plurality of second battery cells may be configured to be wire bonded together.

[0029] The battery cell assembly may further include a first gasket disposed between the main case and the first case, and a second gasket disposed between the main case and the second case.

[0030] The main case and the first case may be configured to be coupled through at least one first fastening member, and the main case and the second case may be configured to be coupled through at least one second fastening member.

[0031] The plurality of first battery cells and the plurality of second battery cells may be configured as cylindrical battery cells, and the main case may be configured to surround the side surfaces of the cylindrical battery cells.

[0032] An adhesive may further be included between the inner surface of the pack case and the battery cell assembly.

[0033] And, the present invention can provide an electric device characterized by including a battery pack according to the present invention.

[0034] The above electrical device may be a LEV.

[0035] In order to solve the above problem, the present invention can provide a method for manufacturing a battery pack, the method comprising: a first step of inserting the first case in a sliding manner toward a first direction into the main case, wherein at least a portion of both sides facing a first direction and a second direction opposite to the first direction are open, and joining the main case and the first case; a second step of joining a BMS assembly electrically connected to the battery cell assembly to the battery cell assembly; a third step of inserting the battery cell assembly in a sliding manner toward the first direction into the main case so that one side of the battery cell assembly faces one side of the first case; and a fourth step of joining the main case and the second case so that one side of the battery cell assembly faces one side of the second case.

[0036] The battery cell assembly may provide a method for manufacturing a battery pack, including a first cell assembly including a plurality of first battery cells and a first cell frame accommodating the plurality of first battery cells, and a second cell assembly stacked with the first cell assembly and including a plurality of second battery cells and a second cell frame accommodating the plurality of second battery cells.

[0037] A method for manufacturing a battery pack can be provided in which the first cell assembly and the second cell assembly are spaced apart from each other, and the electrode terminals of the plurality of first battery cells and the electrode terminals of the plurality of second battery cells are configured to face each other.

[0038] The above battery cell assembly can provide a method for manufacturing a battery pack, further comprising a screen member disposed between the first cell assembly and the second cell assembly.

[0039] A method for manufacturing a battery pack may be provided in which the electrode terminals of the plurality of first battery cells and the plurality of second battery cells are arranged in a central portion of the pack case.

[0040] A method for manufacturing a battery pack may be provided, wherein the main case includes a first opening facing the first direction and a second opening facing the second direction, and is configured to surround the battery cell assembly, and the first case covers the first opening of the main case, and the second case covers the second opening of the main case.

[0041] A method for manufacturing a battery pack may be provided in which the first case covers the first opening from the inside of the main case, and the second case covers the second opening from the outside of the main case.

[0042] A method for manufacturing a battery pack can be provided in which the size of the first case is smaller than the size of the second case.

[0043] A method for manufacturing a battery pack can be provided in which the first case and the second case are each metal plates, the plurality of first battery cells are configured to directly transfer heat to the first case, and the plurality of second battery cells are configured to directly transfer heat to the second case.

[0044] The above main case may provide a method for manufacturing a battery pack further comprising a plurality of side walls and a cover side wall extending vertically from one end of the first direction of the plurality of side walls.

[0045] A method for manufacturing a battery pack may be provided in which one side of the first cell assembly is arranged to be in contact with one side of the first case, and one side of the second cell assembly is arranged to be in contact with one side of the second case.

[0046] The first cell frame includes at least one first hole through which electrode terminals of the plurality of first battery cells are exposed and at least one first receiving groove through which bottom surfaces of the plurality of first battery cells are exposed opposite the electrode terminals of the plurality of first battery cells, and the second cell frame includes at least one second hole through which electrode terminals of the plurality of second battery cells are exposed and at least one second receiving groove through which bottom surfaces of the plurality of second battery cells are exposed opposite the electrode terminals of the plurality of second battery cells. A method for manufacturing a battery pack may be provided.

[0047] A method for manufacturing a battery pack may be provided, further comprising a BMS assembly arranged so that one end is in contact with the first cell assembly and the other end is in contact with the second cell assembly.

[0048] A method for manufacturing a battery pack can be provided in which wire bonding is configured between the plurality of first battery cells and between the plurality of second battery cells.

[0049] The above battery cell assembly may provide a method for manufacturing a battery pack, further comprising a first gasket disposed between the main case and the first case and a second gasket disposed between the main case and the second case.

[0050] A method for manufacturing a battery pack may be provided, wherein the main case and the first case are configured to be coupled through at least one first fastening member, and the main case and the second case are configured to be coupled through at least one second fastening member.

[0051] A method for manufacturing a battery pack may be provided in which the plurality of first battery cells and the plurality of second battery cells are configured as cylindrical battery cells, and the main case is configured to surround the side surfaces of the cylindrical battery cells.

[0052] A method for manufacturing a battery pack can be provided that further includes an adhesive between the inner surface of the pack case and the battery cell assembly.

[0053]

[0054] According to one embodiment of the present invention, heat generated by charging and discharging of a plurality of battery cell assemblies can be directly transferred to the pack case, thereby effectively increasing the cooling efficiency and / or heat transfer efficiency of the battery pack.

[0055] According to another aspect of the present invention, a heat dissipation pad configured to be placed between a plurality of battery cell assemblies and a pack case in an existing battery pack can be omitted, thereby reducing material costs and simplifying the manufacturing process.

[0056] According to another aspect of the present invention, manufacturing efficiency can be improved and assembly can be facilitated by sequentially stacking components of a battery pack in one direction.

[0057] According to another aspect of the present invention, there is also an advantage in that a battery cell assembly structure in which a plurality of battery cell assemblies are stacked in two layers can directly fix the battery cell assemblies to the pack case, thereby enabling CTP implementation.

[0058] According to another aspect of the present invention, by providing a battery pack having high heat transfer efficiency and improved manufacturing efficiency and an electric device including the same, the safety of rapid charging and the efficiency of energy use can be improved.

[0059] In addition, the present invention may have various other effects, which will be described in each embodiment configuration, or an explanation of effects that can be easily inferred by a person skilled in the art will be omitted.

[0060]

[0061] The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0062] Fig. 1 is a perspective view schematically showing a part of the configuration of a conventional battery pack.

[0063] Figure 2 is a cross-sectional diagram along line A1-A1' of Figure 1.

[0064] FIG. 3 is a perspective view showing a battery pack according to one embodiment of the present invention.

[0065] Figure 4 is an exploded perspective view of a battery pack according to one embodiment of the present invention.

[0066] FIG. 5 is a perspective view of a battery pack according to one embodiment of the present invention viewed from a first direction.

[0067] Figure 6 is an exploded perspective view showing a pack case according to one embodiment of the present invention.

[0068] Figure 7 is a front view of an assembled pack case according to one embodiment of the present invention, viewed from a first direction.

[0069] Figure 8 is a front view of an assembled pack case according to one embodiment of the present invention, viewed from a second direction.

[0070] FIG. 9 is a perspective view showing a battery cell assembly and a BMS (battery management system) assembly combined according to one embodiment of the present invention.

[0071] FIG. 10 is an exploded perspective view showing the configuration of a first cell assembly according to one embodiment of the present invention.

[0072] FIG. 11 is an exploded perspective view showing the configuration of a second cell assembly according to one embodiment of the present invention.

[0073] FIG. 12 is a cross-sectional view of a battery pack according to one embodiment of the present invention taken along the Y-axis.

[0074] FIG. 13 is a drawing for explaining an electric device including a battery pack according to one embodiment of the present invention.

[0075]

[0076] 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.

[0077] 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.

[0078] Furthermore, the present invention includes various embodiments. For each embodiment, redundant descriptions of substantially identical or similar components will be omitted, and the differences will be described.

[0079] Additionally, to facilitate understanding of the invention, the attached drawings are not drawn to scale and some components may have exaggerated dimensions. Furthermore, identical components may be assigned the same reference numbers in different embodiments.

[0080] Although terms like "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a "first" component may also be a "second" component.

[0081] Throughout the specification, unless otherwise specifically stated, each element may be singular or plural.

[0082] Hereinafter, the phrase "any configuration is placed on (or below)" a component or "on (or below)" a component may mean that any configuration is placed in contact with the upper surface (or lower surface) of said component, and that other configurations may be interposed between said component and any configuration placed on (or below) said component.

[0083] Additionally, when it is described that a component is "connected," "coupled," or "connected" to another component, it should be understood that the components may be directly connected or connected to one another, but that other components may also be "interposed" between the components, or that each component may be "connected," "coupled," or "connected" through another component.

[0084] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as "consisting of" or "comprising" should not necessarily be construed to include all of the components or steps described in the specification, and should be construed to mean that some of the components or steps may not be included, or that additional components or steps may be included.

[0085] Throughout the specification, when reference is made to “A and / or B,” this means A, B or A and B, unless otherwise specified.

[0086] Meanwhile, in the present invention, terms indicating directions such as up, down, left, right, front, and back may be used, but it is obvious to those skilled in the art that these terms are only for convenience of explanation and may vary depending on the location of the target object or the location of the observer.

[0087] For example, in an embodiment of the present invention, the X-axis direction shown in the drawing may mean a front-back direction, the Y-axis direction may mean a left-right direction perpendicular to the X-axis direction on a horizontal plane (XY plane), and the Z-axis direction may mean an up-down direction (vertical direction) perpendicular to both the X-axis direction and the Y-axis direction.

[0088] Fig. 3 is a perspective view showing a battery pack (300) according to one embodiment of the present invention. Fig. 4 is an exploded perspective view of a battery pack (300) according to one embodiment of the present invention.

[0089] Referring to FIGS. 3 and 4, a battery pack (300) according to one embodiment of the present invention may include a pack case (100), a battery cell assembly (200), and a BMS (battery management system) assembly (260).

[0090] According to one embodiment, at least one surface of the battery cell assembly (200) may be configured to directly face at least one surface of the pack case (100). Here, the term "direct face-to-face" may include not only the case where the battery cell assembly (200) and the pack case (100) are arranged without any intermediate member between them, but also the case where an intermediate member, such as an adhesive, that does not impede direct thermal conduction between the battery cell assembly (200) and the pack case (100) is arranged. In other words, the direct face-to-face may include a state where the bottom surface of the battery cell assembly (200) is in contact with the pack case (100) without an adhesive, or a state where it is attached using an adhesive or the like. For example, the direct face-to-face may refer to a state where the battery cell assembly (200) and the pack case (100) are in close thermal contact with each other without a member thicker than an adhesive, such as a heat dissipation pad, a member that requires more material costs, or a member that requires additional manufacturing steps. According to one embodiment, the battery cell assembly (200) is directly attached to the pack case (100), so that internal heat generated in the battery cell assembly (200) can be directly transferred to the pack case (100). In other words, heat dissipation can be effectively achieved by arranging at least one surface of the battery cell assembly (200) to face at least one surface of the pack case (100). The arrangement and / or structure of the battery cell assembly (200) and the pack case (100) will be described in detail below.

[0091] According to one embodiment, the pack case (100) may be a case configured to accommodate a battery cell assembly (200) in an internal space by combining and / or assembling a plurality of cases. According to one embodiment, the pack case (100) may include a main case (110), a first case (120), and a second case (130).

[0092] According to one embodiment, the main case (110) may be configured to surround a side surface of the battery cell assembly (200). According to one embodiment, the main case (110) may be configured to have a hollow shape in which at least a portion of both sides facing a first direction (-X direction) and a second direction (+X direction) opposite to the first direction are open. For example, the main case (110) may include a first opening facing the first direction (e.g., the first opening (113) of FIG. 6) and a second opening facing the second direction (e.g., the second opening (114) of FIG. 6). The main case (110) may be configured to allow the battery cell assembly (200) and / or the BMS assembly (260) to be inserted into the main case (110) in a sliding manner through the second opening (114). According to one embodiment, the main case (110) is preferably made of a material having high mechanical rigidity and excellent heat dissipation properties so as to protect the battery cell assembly (200) and / or the BMS assembly (260) from external impact. For example, the main case (110) may be made of a metal material. From a weight reduction perspective, the main case (110) may be made of a metal material such as aluminum (AL). From a rigidity perspective, the main case (110) may also be made of a steel series.

[0093] According to one embodiment, the first case (120) may be arranged to cover the first opening (113) facing the first direction of the main case (110). For example, the shape of the first case (120) may be substantially the same as the shape of the first opening (113) of the main case (110). It is preferable that the first case (120) be made of a material having high mechanical rigidity and excellent heat dissipation properties so as to protect the battery cell assembly (200) and / or the BMS assembly (260) from external impact. For example, the first case (120) may be made of a metal material like the main case (110). The first case (120) made of a metal material can implement a heat sink function. Therefore, passive cooling can be achieved by the first case (120), which is an external case, itself, without the need for a separate heat sink.

[0094] According to one embodiment, the second case (130) may be arranged to cover the second opening (114) facing the second direction of the main case (110). For example, the shape of the second case (130) may be substantially the same as the shape of the second opening (114) of the main case (110). It is preferable that the second case (130) be made of a material having high mechanical rigidity and excellent heat dissipation properties so as to protect the battery cell assembly (200) and / or the BMS assembly (260) from external impact. For example, the second case (130) may be made of a metal material like the main case (110) and the first case (120). The second case (130) made of a metal material can implement a heat sink function like the first case (120) made of a metal material, and passive cooling can be achieved by the second case (130) itself, which is an external case, without the need for a separate heat sink. However, the shape and structure of the pack case (100) including the main case (110), the first case (120), and the second case (130) are not limited by the above embodiment, and can be designed and changed by various embodiments that can accommodate the battery cell assembly (200). According to another embodiment, the main case (110) and the first case (120) can be formed integrally. In this case, the assembly process between the main case (110) and the first case (120) can be omitted, and since there is no first opening (113), there is no sealing problem.

[0095] According to one embodiment, a battery cell assembly (200) may include a first cell assembly (210), a second cell assembly (220), a screen member (230), a first gasket (240), and a second gasket (250).

[0096] According to one embodiment, the battery cell assembly (200) may be configured such that two or more cell assemblies are stacked to increase the capacity and output of the battery. The battery cell assembly (200) may include a first cell assembly (210) and a second cell assembly (220) stacked with the first cell assembly (210). For example, the first cell assembly (210) and the second cell assembly (220) may be stacked in the front-back direction (X-axis direction). According to one embodiment, the first cell assembly (210) and the second cell assembly (220) may be sequentially stacked. For example, the shape and / or size of the first cell assembly (210) and the second cell assembly (220) may be substantially the same as the shape and / or size of one side of the pack case (100) facing the X-axis direction. For example, the shape and / or size of the first cell assembly (210) and the second cell assembly (220) may be substantially the same.

[0097] According to one embodiment, the two cell assemblies may include a plurality of battery cells (211, 221) connected in series with m and / or in parallel with n in the form of nPmS (n and m are natural numbers) and a cell frame (212, 222) accommodating the plurality of battery cells. According to one embodiment, the cell frames between the two cell assemblies may be coupled to each other and integrally housed in the pack case (100). That is, the two cell assemblies may be housed inside the pack case (100) in a form in which they are inserted into the interior of the main case (110) in a sliding manner or a force-fit manner while being mechanically and electrically coupled to each other.

[0098] According to one embodiment, the screen member (230) may be disposed between the first cell assembly (210) and the second cell assembly (220). For example, the screen member (230) may be disposed to face at least one surface of each of the first cell assembly (210) and the second cell assembly (220). The screen member (230) may be configured for heat dissipation and / or insulation so as to block flame or heat and electrically insulate between the first cell assembly (210) and the second cell assembly (220). For example, the screen member (230) may include mica and / or glass fiber (GF). For example, the shape and / or size of the screen member (230) may be substantially the same as the shape and / or size of one surface facing the X-axis direction of the pack case (100).

[0099] According to one embodiment, a high-compressibility gasket, a gap filler, etc. may be applied between the cases configured to be coupled to each other. According to one embodiment, a first gasket (240) may be disposed between the main case (110) and the first case (120) to fill the gap between the main case (110) and the first case (120). The first gasket (240) may be disposed at a position corresponding to a position where the main case (110) and the first case (120) are coupled. The first gasket (240) may have a closed curve shape including an opening. The first gasket (240) may be responsible for waterproofing and airtightness, i.e., sealing.

[0100] Similarly, the second gasket (250) may be placed between the main case (110) and the second case (130) to fill the gap between the main case (110) and the second case (130). The second gasket (250) may be placed at a position corresponding to a position where the main case (110) and the second case (130) are joined. The second gasket (250) may have a closed curve shape including an opening. The second gasket (250) may also perform sealing.

[0101] According to one embodiment, the pack case (100) may further include a BMS assembly (260) electrically connected to the battery cell assembly (200). The BMS assembly (260) may be provided between the pack case (100) and the battery cell assembly (200) so as to be detachably coupled to the pack case (100) and the battery cell assembly (200).

[0102] According to one embodiment, the battery pack (300) may have a predetermined length in the X-axis direction, a predetermined width in the Y-axis direction, and a predetermined height in the Z-axis direction, and may have a polygonal appearance when viewed from the X-axis direction. When the battery pack (300) is mounted on a vehicle such as an EV or HEV, the mounting space is limited due to the vehicle components arranged with a high degree of integration. Therefore, it is preferable that the battery pack (300) be formed as a rectangular parallelepiped structure with a large height relative to its length and a large front-rear length relative to the height so that it can be mounted in a narrow space such as between the driver's seat and the passenger seat. The battery pack (300) may also be formed as a tunnel-shaped structure. The appearance of the battery pack (300) may vary depending on the pack case (100). In addition, the battery pack (300) may be mounted on an LEV such as an electric bicycle, an electric scooter, an electric ATV / UTV, an electric lawn mower, an automatic forklift, a delivery robot, an automated guided vehicle (AGV), and may have an appearance as illustrated in FIG. 1. However, the shape and / or size of the battery pack (300) is not limited by the above embodiment and may be designed in various ways depending on the specifications of the product to which it is applied.

[0103] According to one embodiment, referring to FIG. 4, the battery pack (300) according to the present invention may be configured such that a first case (120), a battery cell assembly (200), and a second case (130) are sequentially stacked in the internal space of the main case (110). Specifically, the battery pack (300) according to the present invention may be configured such that a first case (120), a first gasket (240), a first cell assembly (210), a screen member (230), a second cell assembly (220), a second gasket (250), and a second case (130) are sequentially stacked in the internal space of the main case (110). In this way, the battery pack (300) according to the present invention can stack components of the battery pack (300) in one direction, thereby improving manufacturing efficiency and facilitating assembly. A method for manufacturing a battery pack (300) according to the present invention will be described in detail below.

[0104] Fig. 5 is a perspective view of a battery pack (300) according to one embodiment of the present invention when viewed from a first direction. Fig. 6 is an exploded perspective view showing a pack case (100) according to one embodiment of the present invention in an exploded state. Fig. 7 is a front view of an assembled pack case (100) according to one embodiment of the present invention when viewed from a first direction. Fig. 8 is a front view of an assembled pack case (100) according to one embodiment of the present invention when viewed from a second direction.

[0105] Referring to FIGS. 5 to 8, a battery pack (300) according to an embodiment of the present invention may include a pack case (100), a battery cell assembly (200), and a BMS assembly (260). The configuration of the pack case (100), the battery cell assembly (200), and the BMS assembly (260) of FIGS. 5 to 8 may be all or part of the same as the configuration of the pack case (100), the battery cell assembly (200), and the BMS assembly (260) of FIGS. 3 and 4. The embodiment of FIGS. 5 to 8 may be partially combined with the embodiment of FIGS. 3 and 4.

[0106] According to one embodiment, the pack case (100) may be configured to accommodate a battery cell assembly (200) in an internal space by combining and / or assembling a main case (110), a first case (120), and a second case (130). According to one embodiment, the main case (110) may have a hollow shape in which at least a portion of both sides facing a first direction and a second direction opposite to the first direction is open. According to one embodiment, the main case (110) may include a first opening (113) facing the first direction and a second opening (114) facing the second direction. For example, the size of the first opening (113) and the size of the second opening (114) may be different from each other. For example, the size of the first opening (113) may be smaller than the size of the second opening (114). The main case (110) may be configured to insert the battery cell assembly (200) and / or the BMS assembly (260) into the interior of the main case (110) in a sliding manner through the second opening (114).

[0107] According to one embodiment, the main case (110) may have a polygonal shape when viewed in the X-axis direction. For example, the main case (110) may have a polygonal shape with one portion being concave when viewed in the X-axis direction. The shape and / or size of the main case (110) may correspond to the shape and / or size of the battery pack (300), and one side of the components constituting the battery pack (300) facing the X-axis direction may have a shape substantially corresponding thereto.

[0108] According to one embodiment, with reference to FIG. 5, the main case (110) may include a plurality of side walls (112) facing in a direction perpendicular to the first direction. For example, the plurality of side walls (112) of the main case (110) may include a first side wall (112a), a second side wall (112b) inclined at a specified angle from the first side wall (112a), a third side wall (112c) inclined at a specified angle from the second side wall (112b), a fourth side wall (112d) inclined at a specified angle from the third side wall (112c) and substantially parallel to the first side wall (112a), a fifth side wall (112e) inclined at a specified angle from the fourth side wall (112d), a sixth side wall (112f) inclined at a specified angle from the fifth side wall (112e) and parallel to the first side wall (112a), and a seventh side wall (112g) inclined at a specified angle from the sixth side wall (112f) and in contact with the first side wall (112a). For example, the outer surface of the sixth side wall (112f) may be formed to be inclined at a first angle (θ) with respect to the outer surface of the seventh side wall (112g). For example, the first angle (θ) may be an acute angle greater than or equal to 0 degrees and less than or equal to 90 degrees. For example, the main case may have a polygonal shape in which the portion where the sixth side wall (112f) and the seventh side wall (112g) meet is concave when viewed in the X-axis direction. Hereinafter, the portion where the sixth side wall (112f) and the seventh side wall (112g) meet is defined as a 'concave portion'. Such a 'concave portion' may collectively refer to all corresponding portions of components constituting the battery pack (300) as well as the main case (110).

[0109] According to one embodiment, the main case (110) may further include a cover side wall (111) extending vertically from one end of the plurality of side walls (112) in the first direction. The cover side wall (111) may extend inwardly from one end of the plurality of side walls (112) in the first direction. The cover side wall (111) may be arranged to face the first direction. The cover side wall (111) may extend vertically from one end of the plurality of side walls (112) by a first length (d). The cover side wall (111) may be, for example, a closed curve in which a first opening (113) is formed and whose thickness is the first length (d). According to one embodiment, the first case (120) may be configured to be coupled with the cover side wall (111).

[0110] According to one embodiment, the first case (120) can cover the first opening (113) from the inside of the main case (110). For example, the first case (120) can be assembled to cover the first opening (113) of the main case (110) in a sliding manner through the internal space of the main case (110). For example, the first case (120) can be inserted into the inside of the main case (110) in a sliding manner in a first direction and combined with the main case (110). For example, the shape and / or size of the first case (120) can substantially correspond to the shape and / or size of the first opening (113).

[0111] In one embodiment, the second case (130) can cover the second opening (114) from the outside of the main case (110). For example, the second case (130) can be assembled to cover the second opening (114) from the outside of the second opening (114) after the first case (120) and the battery cell assembly (200) are assembled. For example, the first case (120) can be inserted into the second opening (114) of the main case (110) toward the first direction and combined with the main case (110). For example, the shape and / or size of the second case (130) can substantially correspond to the shape and / or size of the second opening (114).

[0112] In one embodiment, the size of the first case (120) and the size of the second case (130) may be different. In one embodiment, the size of the first case (120) may be smaller than the size of the second case (130). For example, the size of the first case (120) may be smaller than the size of the second case (130) by approximately the thickness of the cover side wall (111), i.e., a first length (d). Since the first case (120) covers the first opening (113) on the inside of the main case (110) and the second case (130) covers the second opening (114) on the outside of the main case (110), the first case (120) that must be slidably coupled inside the main case (110) may be relatively small in size. In this way, according to one embodiment of the present invention, since the sizes of the first case (120) and the second case (130) are different from each other, the components of the battery pack (300) can be stacked in one direction (e.g., in the X-axis direction). According to one embodiment of the present disclosure, the pack case (100), the battery cell assembly (200), and the BMS assembly (260) constituting the battery pack (300) can be stacked in one direction, thereby improving manufacturing efficiency and providing a battery pack (300) that is easy to assemble. This structure can also be advantageous for fixing and / or assembling the first gasket (240) and the second gasket (250).

[0113] According to one embodiment, the first case (120) and the second case (130) may be coupled and / or fixed to the main case (110). For example, the first case (120) and the second case (130) may be bolted to the main case (110) or coupled to each other by a male-female coupling structure (not shown).

[0114] According to one embodiment, the main case (110) and the first case (120) may be coupled through at least one first fastening member (101), and the main case (110) and the second case (130) may be coupled through at least one second fastening member (102). According to one embodiment, the at least one first fastening member (101) may be spaced apart at a regular interval along an edge portion of the first case (120). For example, the at least one first fastening member (101) may include a plurality of fastening members spaced apart along a rim portion of the first case (120). Similarly, the at least one second fastening member (102) may be spaced apart at a regular interval along an edge portion of the second case (130). For example, the at least one second fastening member (102) may include a plurality of fastening members spaced apart along a rim portion of the second case (130). The first fastening member (101) and the second fastening member (102) may be, for example, bolts.

[0115] According to one embodiment, the main case (110) may include at least one first fastening groove (115) formed on one surface facing the first direction. For example, the at least one first fastening groove (115) may be formed on a cover side wall (111) of the main case (110). The first case (120) may include at least one first recess (121) configured at an edge thereof so that at least one first fastening member (101) may penetrate therethrough. For example, the at least one first fastening member (101) may be inserted into the main case (110) and the first case (120) along the second direction. For example, the at least one first fastening member (101) may penetrate the at least one first recess (121) of the first case (120) and be inserted into the at least one first fastening groove (115) of the main case (110). According to one embodiment, the number, position and / or size of at least one first fastening member (101), at least one first fastening groove (115) and at least one first recess (121) may correspond to each other.

[0116] According to one embodiment, the main case (110) may include at least one second fastening groove (116) formed on one surface facing the second direction. For example, the at least one second fastening groove (116) may be formed on a rim portion of a plurality of side walls (112) of the main case (110). The second case (130) may include at least one second recess (131) configured at an edge thereof so that at least one second fastening member (102) may pass therethrough. For example, the at least one second fastening member (102) may be inserted into the main case (110) and the third case (130) along the first direction. For example, the at least one second fastening member (102) may pass through the at least one second recess (131) of the second case (130) and be inserted into the at least one second fastening groove (116) of the main case (110). According to one embodiment, the number, position and / or size of at least one second fastening member (102), at least one second fastening groove (116) and at least one second recess (131) may correspond to each other.

[0117] For example, at least one first fastening groove (115), at least one second fastening groove (116), at least one first recess (121) and / or at least one second recess (131) may be an opening perforated in the X-axis direction or a portion recessed in one direction (e.g., inward direction).

[0118] However, the method by which the first case (120) and the second case (130) are coupled and / or fixed to the main case (110) is not limited by the above embodiment, and various design modifications are possible. In addition, the method by which the first case (120) is coupled and / or fixed to the main case (110) and the method by which the second case (130) is coupled and / or fixed to the main case (110) may be substantially the same or different from each other.

[0119] Fig. 9 is a perspective view showing a battery cell assembly (200) and a BMS assembly (260) combined according to one embodiment of the present invention. Fig. 10 is an exploded perspective view showing the configuration of a first cell assembly (210) according to one embodiment of the present invention in isolation. Fig. 11 is an exploded perspective view showing the configuration of a second cell assembly (220) according to one embodiment of the present invention in isolation.

[0120] Referring to FIGS. 9 to 11, a battery pack (300) according to an embodiment of the present invention may include a pack case (100), a battery cell assembly (200), and a BMS assembly (260). The configuration of the pack case (100), the battery cell assembly (200), and the BMS assembly (260) of FIGS. 9 to 11 may be all or part of the same as the configuration of the pack case (100), the battery cell assembly (200), and the BMS assembly (260) of FIGS. 5 to 8. The embodiment of FIGS. 9 to 11 may be partially combined with the embodiment of FIGS. 5 to 8.

[0121] According to one embodiment, the battery cell assembly (200) may be stacked in the order of a first gasket (240), a first cell assembly (210), a screen member (230), a second cell assembly (220), and a second gasket (250) from a first direction to a second direction. In this way, the battery cell assembly (200) according to the present invention can stack components in one direction and be sequentially arranged within the pack case (100), thereby improving manufacturing efficiency and facilitating assembly.

[0122] In addition, there is an advantage in that the battery cell assembly (200) can be directly fixed to the pack case (100) in a structure including a battery cell assembly (200) in which multiple cell assemblies are stacked in two layers, thereby enabling CTP implementation.

[0123] According to one embodiment, the first cell assembly (210) may include a plurality of first battery cells (211), a first cell frame (212) accommodating the plurality of first battery cells (211), a first plate-shaped bus bar (213), and a first sensing unit (214). Similarly, the second cell assembly (220) may include a plurality of second battery cells (221), a second cell frame (222) accommodating the plurality of second battery cells (221), a second plate-shaped bus bar (223), and a second sensing unit (224). The configuration and structure of the second cell assembly (220) are substantially the same as those of the first cell assembly (210), and a description of the second cell assembly (220) will be omitted below.

[0124] According to one embodiment, the plurality of first battery cells (211) may be composed of cylindrical battery cells. The plurality of first battery cells (211) may be aligned at a constant interval. The plurality of first battery cells (211) may be connected in series by m and / or in parallel by n in the form of nPmS (n and m are natural numbers). For example, the plurality of first battery cells (211) may be arranged to correspond to the shape of the main case (110). For example, to correspond to a polygonal shape with a portion being concave, the plurality of first battery cells (211) may include aligned battery cells extending vertically (in the Y-axis direction) in the lower portion (in the -Z-axis direction) according to the shape of the battery pack (300) and aligned battery cells positioned only in the left portion (in the -Y-axis direction) in the upper portion (in the +Z-axis direction).

[0125] According to one embodiment, each of the cylindrical battery cells constituting the plurality of first battery cells (211) may be stacked in a lying state so that the first electrode terminal (e.g., positive terminal (+)) or the second electrode terminal (e.g., negative terminal (-)) is positioned at both ends facing the first direction or the second direction. Each cylindrical battery cell may be formed by placing an electrolyte and an electrode assembly into a battery can through an open end of a cylindrical battery can and sealing the open end of the battery can. Each cylindrical battery cell may have an electrode assembly wound in a jelly-roll shape with a separator interposed between a positive plate and a negative plate, and the positive plate may be electrically connected to the first electrode terminal and the negative plate may be electrically connected to the second electrode terminal. For example, the first electrode terminal may be a rivet inserted through the surface opposite the open end of the battery can, and the open end of the battery can may be finished by beading and crimping together with a cap plate. In this case, the battery can may function as the second electrode terminal. Here, the battery can may be treated so that only a specific part functions as an electrode terminal, and the remaining parts may be coated with an insulating film or insulating material.

[0126] In particular, the upper surface of the battery can around the first electrode terminal can be used as the second electrode terminal. Then, the plurality of first battery cells (211) can have a structure in which a first electrode terminal having a first polarity and a second electrode terminal having a second polarity and being electrically insulated from the first electrode terminal are provided on one side in the longitudinal direction (parallel to the X-axis). That is, since a pair of electrode terminals are positioned in the same direction, when electrically connecting the plurality of first battery cells (211), it may be possible to place electrical connection components such as a bus bar only on one side of the plurality of first battery cells (211). This can lead to simplification of the structure of the battery pack (300) and improvement of energy density.

[0127] For example, the plurality of first battery cells (211) may be configured as battery cells in the form of 4680. Here, 4680 represents a form factor. The first two numbers in the form factor represent the diameter of the secondary battery, and the remaining numbers represent the height of the secondary battery. The 4680 cell has high efficiency and a large size compared to the existing 18650 cell or 21700 cell. A battery pack (300) including such battery cells can be implemented to have an optimal layout for LEV use according to the present invention.

[0128] According to one embodiment, each of the plurality of first battery cells (211) may be wire bonded to each other or connected to a bus bar. Here, wire bonding may mean ultrasonically pressing both ends of a metal wire to each bonding target. However, wire bonding may not necessarily be performed using ultrasonic waves, but other bonding techniques, such as laser welding, may also be applied. According to another embodiment, each of the plurality of first battery cells (211) may be bonded to each other by resistance welding. However, the bonding method of the plurality of battery cells is not limited to the above embodiment, and may be designed in various ways.

[0129] According to one embodiment, the first cell frame (212) may be arranged to surround the side surfaces of the plurality of first battery cells (211). According to one embodiment, the first cell frame (212) may include a first surface (2121) including at least one first hole (2122) and a second surface (2123) including at least one first receiving groove (2124) and facing in an opposite direction to the first surface (2121). According to one embodiment, the second cell frame (222) may include a third surface (2221) including at least one second hole (2222) and a fourth surface (2223) including at least one second receiving groove (2224) and facing in an opposite direction to the third surface (2221).

[0130] According to one embodiment, at least one first hole (2122) of the first cell frame (212) and at least one second hole (2222) of the second cell frame (222) may be arranged to face each other at a central portion of the battery pack (300). For example, a first surface (2121) including at least one first hole (2122) of the first cell frame (212) and a third surface (2221) including at least one second hole (2222) of the second cell frame (222) may be arranged at a central portion of the battery pack (300) with respect to the X-axis direction. For example, the second surface (2123) including at least one first receiving groove (2124) of the first cell frame (212) and the fourth surface (2223) including at least one second receiving groove (2224) of the second cell frame (222) may be arranged at an edge portion of the battery pack (300) with respect to the X-axis direction.

[0131] According to one embodiment, at least one first receiving groove (2124) may be configured to expose bottom surfaces of the plurality of first battery cells (211) opposite to the first electrode terminals of the plurality of first battery cells (211). According to one embodiment, the at least one first receiving groove (2124) may be provided so that each battery cell constituting the plurality of first battery cells (211) may be received at a predetermined interval. For example, the size and shape of the at least one first receiving groove (2124) may be substantially the same as the size and shape of the plurality of first battery cells (211). According to one embodiment, the first electrode terminals of the plurality of first battery cells (211) may be exposed through the at least one first hole (2122). According to one embodiment, at least a portion of the at least one first hole (2122) and the at least one first receiving groove (2124) may correspond to each other. However, at least one first hole (2122) and at least one first receiving groove (2124) may not substantially match in size and / or shape.

[0132] According to one embodiment, the first plate-shaped bus bar (213) may be disposed on one surface of the first cell frame (212). According to one embodiment, the first plate-shaped bus bar (213) may be disposed on the first surface (2121) of the first cell frame (212). For example, the first plate-shaped bus bar (213) may be detachably coupled to the first surface (2121) of the first cell frame (212). The first plate-shaped bus bar (213) may be disposed on the first electrode terminals of the plurality of first battery cells (211) to electrically connect the plurality of first battery cells (211) to each other. By using such a bus-bar connection, the space in the X-axis direction used for electrical connection can be reduced, and the dead space is reduced, which is advantageous for increasing energy density. For example, the first electrode terminals of the plurality of first battery cells (211) may be attached to the surface of the first plate-shaped bus bar (213). That is, the first electrode terminals of the plurality of first battery cells (211) can be electrically connected to each other by welding the ends of the corresponding first plate-shaped bus bars (213). One end of the first plate-shaped bus bar (213) can be connected to a printed circuit board (not shown). The printed circuit board (not shown) can sense the voltage characteristics of the plurality of first battery cells (211) through the first plate-shaped bus bar (213) and transmit the voltage information to the BMS assembly (260) connected to the cable connector.

[0133] According to one embodiment, the first sensing unit (214) can sense voltage information of a plurality of first battery cells (211). The first sensing unit (214) is electrically connected to the plurality of first battery cells (211) and can be disposed on one surface of the first cell frame (212). For example, the first sensing unit (214) can be disposed on the first surface (2121) including at least one first hole (2122) of the first cell frame (212). The first sensing unit (214) can be disposed adjacent to the first plate-shaped bus bar (213) and electrically connected to the first plate-shaped bus bar (213) by wire bonding.

[0134] According to one embodiment, the first plate-shaped busbar (213) may further include a first extension portion (2131) that extends and protrudes in the X-axis direction. Similarly, the second plate-shaped busbar (223) may further include a second extension portion (2231) that extends and protrudes in the X-axis direction. According to one embodiment, the battery cell assembly (200) may further include an inter-busbar (225) that connects the first extension portion (2131) of the first plate-shaped busbar (213) and the second extension portion (2231) of the second plate-shaped busbar (223). The first plate-shaped busbar (213) and the second plate-shaped busbar (223) may be electrically connected through the inter-busbar (225). For example, the inter-busbar (225) may be coupled to the first cell frame (212) and the second cell frame (222).

[0135] According to one embodiment, the first gasket (240) may be disposed between the first cell assembly (210) and the first case (120). The first gasket (240) may be disposed at a position corresponding to a position where the cover side wall (111) of the main case (110) and the first case (120) are coupled. The size and shape of the first gasket (240) may substantially correspond to the shape of the first opening (113) of the main case (110) or the size and shape of the first case (120). According to one embodiment, the size of the first gasket (240) may be smaller than the size of the second gasket (250). According to one embodiment, the first gasket (240) may further include at least one fastening groove (not shown) through which at least one first fastening member (101) may pass.

[0136] According to one embodiment, the second gasket (250) may be disposed between the second cell assembly (220) and the second case (130). The second gasket (250) may be disposed at a position corresponding to a position where the main case (110) and the second case (130) are coupled. The size and shape of the second gasket (250) may substantially correspond to the shape of the second opening (114) of the main case (110) or the size and shape of the second case (130). According to one embodiment, the size of the second gasket (250) may be larger than the size of the first gasket (240). According to one embodiment, the second gasket (250) may further include at least one fastening groove (not shown) through which at least one second fastening member (102) may pass.

[0137] According to one embodiment, the BMS assembly (260) may be coupled to a portion of the battery cell assembly (200). For example, one end of the BMS assembly (260) may be arranged to be in contact with the first cell assembly (210), and the other end may be arranged to be in contact with the second cell assembly (220). For example, the BMS assembly (260) may be coupled to a concave portion of the battery cell assembly (200) (e.g., a portion corresponding to the portion where the sixth side wall (112f) and the seventh side wall (112g) of FIG. 5 meet). However, the coupling position and / or arrangement of the BMS assembly (260) is not limited by the above embodiment, and when coupled to a portion of the battery cell assembly (200), the coupling position may be set in various ways.

[0138] According to one embodiment, the BMS assembly (260) may be composed of a BMS circuit board (not shown) on which a BMS chip and a current sensor, etc. are mounted, and a BMS housing (not shown) that supports the BMS circuit board. The BMS housing may be detachably assembled along the battery cell assembly (200) and integrally fixedly connected to the battery cell assembly (200). The BMS assembly (260) may be assembled in such a manner that it is electrically and structurally connected to the first cell assembly (210) and the second cell assembly (220) while being fixed to the battery cell assembly (200) in this manner. The BMS circuit board of the BMS assembly (260) and the battery cells of the battery cell assembly (200) may be electrically connected to each other by components such as bus bars, cables, and connectors, which are well known to those skilled in the art, and thus a detailed description thereof will be omitted.

[0139] In the battery cell assembly (200), the electrical connection between the plurality of first battery cells (211) in the first cell assembly (210) is made on the upper surface of the first cell assembly (210), and the electrical connection between the plurality of second battery cells (221) in the second cell assembly (220) is made on the upper surface of the second cell assembly (210). This electrical connection portion may be a central portion of the battery cell assembly (200). Since the electrical connection uses a bus bar, dead space can be reduced, and the connection method can be spot welding using laser welding or resistance welding, so that the connection configuration can be simplified. In addition, additional battery cells can be filled in the pack case (100) by the amount of the reduced dead space. Alternatively, the size of the pack case (100) can be made compact by the amount of the reduced dead space. That is, the cell capacity and electric capacity per unit volume can be relatively excellent. Accordingly, the energy density of the battery pack (300) can be improved compared to the conventional one.

[0140] Fig. 12 is a cross-sectional view of a battery pack (300) according to one embodiment of the present invention taken along the Y-axis direction.

[0141] Referring to FIG. 12, a battery pack (300) according to an embodiment of the present invention may include a pack case (100), a battery cell assembly (200), and a BMS assembly (260). The configuration of the pack case (100), the battery cell assembly (200), and the BMS assembly (260) of FIG. 12 may be all or part of the same as the configuration of the pack case (100), the battery cell assembly (200), and the BMS assembly (260) of FIGS. 9 to 11. The embodiment of FIG. 12 may be partially combined with the embodiments of FIGS. 9 to 11.

[0142] According to one embodiment, at least one surface of the battery cell assembly (200) may be configured to directly face at least one surface of the pack case (100). Specifically, according to one embodiment, one surface of the first cell assembly (210) may be arranged to be in contact with one surface of the first case (120), and one surface of the second cell assembly (220) may be arranged to be in contact with one surface of the second case (130). Bottom surfaces of the plurality of first battery cells (211) are exposed through at least one first hole (2122) of the first cell frame (212), and bottom surfaces of the plurality of second battery cells (221) are exposed through at least one second hole (2222) of the second cell frame (222). Accordingly, the plurality of first battery cells (211) can directly transfer heat to the first case (120) through their respective exposed bottom surfaces, and the plurality of second battery cells (221) can directly transfer heat to the second case (130) through their respective exposed bottom surfaces. According to the present invention, the battery cell assembly (200) is directly attached to the pack case (100), so that internal heat generated in the battery cell assembly (200) can be directly transferred to the pack case (100). In other words, heat dissipation can be effectively achieved by arranging at least one surface of the battery cell assembly (200) to directly face at least one surface of the pack case (100). In addition, since the first case (120) and the second case (130) are each metal plates, heat dissipation can be more effectively achieved when the plurality of first battery cells (211) directly transfer heat to the first case (120) and the plurality of second battery cells (221) directly transfer heat to the second case (130).

[0143] That is, the high heat generated through the plurality of first battery cells (211) and / or the plurality of second battery cells (221) can be discharged to the outside through the first case (120) and / or the second case (130) directly connected to the bottom surface. At this time, the plurality of first battery cells (211) and / or the plurality of second battery cells (221) and the first case (120) and / or the second case (130) can be in complete face-to-face contact without any empty space between them. Accordingly, the high temperature of the plurality of first battery cells (211) and / or the plurality of second battery cells (221) can be naturally cooled to the outside through the first case (120) and / or the second case (130) in a passive cooling manner. In the case of a battery pack used in the field of small battery packs, it may be difficult to provide an active cooling structure due to space constraints or product unit price reasons. Therefore, cooling of a battery pack using a passive cooling method such as the present invention can be efficient.

[0144] According to one embodiment, at least one surface of the battery cell assembly (200) may be fixed to at least one surface of the pack case (100) via an adhesive. For example, the battery pack (300) may further include a first adhesive (103) disposed between the first case (120) and the first cell assembly (210) and a second adhesive (104) disposed between the second case (130) and the second cell assembly (220). The first adhesive (103) and the second adhesive (104) are very thin, so that heat transfer is easy, and heat loss through the adhesive may not be substantially considered.

[0145] In one embodiment, a separate heat dissipation pad (e.g., thermal interface material; TIM) between the battery cell assembly (200) and the pack case (100) may be omitted. By omitting the heat dissipation pad, heat dissipation loss is eliminated, material costs are reduced, and the manufacturing process can be simplified.

[0146] According to one embodiment, the first cell assembly (210) and the second cell assembly (220) may be spaced apart from each other. For example, the first cell assembly (210) and the second cell assembly (220) may be spaced apart from each other by a specified distance (g). For example, the specified distance (g) may be defined as at least a minimum safety distance. Here, the minimum safety distance is a distance obtained through an experiment in which battery cells are overcharged and exploded, and may mean a minimum safety distance between the first cell assembly (210) and the second cell assembly (220) such that when one of the facing battery cells explodes, the battery cells located on the opposite side do not cause a chain reaction fire. For example, the specified distance (g) needs to be designed to be approximately 5 mm or more. However, the minimum safety distance is not limited by the above embodiment, and may slightly differ depending on the type, capacity, specifications, etc. of the battery cells included in the battery pack (300).

[0147] According to one embodiment, the screen member (230) may be disposed between the first cell assembly (210) and the second cell assembly (220). The screen member (230) and each of the first cell assemblies (210) and the second cell assemblies (220) may be disposed at a distance greater than a specified distance. This may be to prevent a problem in which, when a flame is emitted from one battery cell, the emitted flame is reflected on the screen member (230) and directed to another battery cell within the same cell assembly.

[0148] According to one embodiment, at least one side of the screen member (230) may be configured to be in contact with at least a portion of the main case (110). At least one side of the screen member (230) may be fixed to at least a portion of the main case (110). For example, the main case (110) may further include a recess, a hook, and / or a protrusion for fixing the screen member (230). However, the method for fixing the position of the screen member (230) is not limited by the above embodiment and may be designed in various ways.

[0149] According to the present embodiment, electrical connection is made at the first electrode terminal side located on the upper side of a plurality of battery cells (211, 221), and by simplifying the electrical connection, the energy density of the entire battery pack (300) is improved, and the bottom surface of the battery cell (211, 221) is directly faced to the pack case (100), so that the heat of the battery cell (211, 221) can be naturally cooled to the outside, so that it can be easily applied to a small battery pack. Such a small battery pack can be utilized for LEV purposes.

[0150] Hereinafter, a method for manufacturing a battery pack (300) according to one embodiment of the present invention will be described.

[0151] According to one embodiment, a method for manufacturing a battery pack (300) may include a first step of inserting a first case (120) into the main case (110) in a sliding manner toward the first direction to join the main case (110) and the first case (120), a second step of joining a BMS assembly (260) to a battery cell assembly (200), a third step of inserting a battery cell assembly (200) into the main case (110) in a sliding manner toward the first direction, and a fourth step of joining the main case (110) and the second case (130).

[0152] According to one embodiment, in the second step, the battery cell assembly (200) may be stacked in the order of the first gasket (240), the first cell assembly (210), the screen member (230), the second cell assembly (220), and the second gasket (250) from the first direction to the second direction. In this way, the battery cell assembly (200) according to the present invention can stack components in one direction and be sequentially arranged within the pack case (100).

[0153] According to one embodiment, in the third step, one side of the first cell assembly (210) and one side of the first case (120) may be arranged to directly face each other. According to one embodiment, in the fourth step, one side of the second cell assembly (220) and one side of the second case (130) may be arranged to directly face each other.

[0154] The battery pack (300) according to the present invention can be stacked in one direction from the first direction to the second direction, thereby improving manufacturing efficiency and facilitating assembly.

[0155] FIG. 13 is a drawing for explaining an electric device including a battery pack (300) according to one embodiment of the present invention.

[0156] Referring to FIG. 13, an electric device (3) according to one embodiment of the present invention may include a battery pack (300) according to one embodiment of the present invention. The electric device may operate by receiving power from the battery pack (300) according to one embodiment of the present invention.

[0157] Preferably, the electric device (3) may be an LEV. Examples of LEVs include e-bikes, e-scooters, and electric golf carts. Since these LEVs are outdoor vehicles, the battery pack (300) must have good waterproof properties to prevent external liquids (e.g., rainwater) from flowing through the battery pack (300). Therefore, a waterproof rating of IP67 is a basic requirement for these LEVs. The battery pack (300) of the present invention can satisfy this waterproof performance by the structure of the pack case (100) and the first and second gaskets (240, 250).

[0158] In addition, since LEVs are ridden by users, safety must be ensured. The battery pack (300) is arranged so that the first cell assembly (210) and the second cell assembly (220) are spaced apart by a specified distance (g) so that when one of the facing battery cells explodes, the battery cells located on the opposite side do not cause a chain reaction fire.

[0159] As described above, although the present invention has been described by limited embodiments and drawings, the present invention is not limited thereto, and various modifications and variations are possible by a person having ordinary skill in the art to which the present invention pertains within the scope of the technical idea of ​​the present invention and the equivalent scope of the claims to be described below.

Claims

1. A pack case includes a main case, a first case, and a second case, and a first step of combining the main case and the first case by slidingly inserting the first case into the main case, which has at least a portion of both sides facing a first direction and a second direction opposite to the first direction open, toward the first direction; A second step of joining a BMS assembly electrically connected to the battery cell assembly to the battery cell assembly; A third step of inserting the battery cell assembly into the main case in a sliding manner toward the first direction so that one side of the battery cell assembly and one side of the first case face each other; and A method for manufacturing a battery pack, comprising: a fourth step of combining the main case and the second case so that one side of the battery cell assembly and one side of the second case face each other.

2. In paragraph 1, The above battery cell assembly, A first cell assembly comprising a plurality of first battery cells and a first cell frame accommodating the plurality of first battery cells; and A method for manufacturing a battery pack, comprising: a second cell assembly, which is stacked with the first cell assembly and includes a plurality of second battery cells and a second cell frame that accommodates the plurality of second battery cells; 3. In paragraph 2, The first cell assembly and the second cell assembly are spaced apart from each other, A method for manufacturing a battery pack, wherein the electrode terminals of the plurality of first battery cells and the electrode terminals of the plurality of second battery cells are configured to face each other.

4. In paragraph 2, The above battery cell assembly, A method for manufacturing a battery pack further comprising a screen member disposed between the first cell assembly and the second cell assembly.

5. In paragraph 2, A method for manufacturing a battery pack, wherein the electrode terminals of the plurality of first battery cells and the plurality of second battery cells are arranged in the central portion of the pack case.

6. In paragraph 2, The main case includes a first opening facing the first direction and a second opening facing the second direction, and is configured to surround the battery cell assembly, The above first case covers the above first opening of the above main case, A method for manufacturing a battery pack, wherein the second case covers the second opening of the main case.

7. In paragraph 6, A method for manufacturing a battery pack, wherein the first case covers the first opening from the inside of the main case, and the second case covers the second opening from the outside of the main case.

8. In paragraph 6, A method for manufacturing a battery pack, wherein the size of the first case is smaller than the size of the second case.

9. In paragraph 6, The above first case and the above second case are each a metal plate, The above plurality of first battery cells directly transfer heat to the first case, A method for manufacturing a battery pack, wherein the plurality of second battery cells are configured to directly transfer heat to the second case.

10. In paragraph 1, A method for manufacturing a battery pack, wherein the main case further comprises a plurality of side walls and a cover side wall extending vertically from one end of the first direction of the plurality of side walls.

11. In paragraph 2, One side of the first cell assembly is arranged to be in contact with one side of the first case, A method for manufacturing a battery pack, wherein one side of the second cell assembly is arranged to be in contact with one side of the second case.

12. In paragraph 2, The first cell frame includes at least one first hole through which electrode terminals of the plurality of first battery cells are exposed and at least one first receiving groove that exposes bottom surfaces of the plurality of first battery cells opposite to the electrode terminals of the plurality of first battery cells, A method for manufacturing a battery pack, wherein the second cell frame includes at least one second hole through which electrode terminals of the plurality of second battery cells are exposed and at least one second receiving groove through which bottom surfaces of the plurality of second battery cells are exposed, the bottom surfaces of the plurality of second battery cells being opposite to the electrode terminals of the plurality of second battery cells.

13. In paragraph 2, A method for manufacturing a battery pack further comprising a BMS assembly, wherein one end is arranged to be in contact with the first cell assembly and the other end is arranged to be in contact with the second cell assembly.

14. In paragraph 2, A method for manufacturing a battery pack, wherein wire bonding is configured between the plurality of first battery cells and between the plurality of second battery cells.

15. In paragraph 1, The above battery cell assembly, A first gasket disposed between the main case and the first case; and A method for manufacturing a battery pack, further comprising: a second gasket disposed between the main case and the second case.

16. In paragraph 1, The above main case and the above first case are configured to be coupled through at least one first fastening member, A method for manufacturing a battery pack, wherein the main case and the second case are configured to be joined through at least one second fastening member.

17. In paragraph 2, The plurality of first battery cells and the plurality of second battery cells are composed of cylindrical battery cells, A method for manufacturing a battery pack, wherein the main case is configured to surround the sides of the cylindrical battery cells.

18. In paragraph 1, A method for manufacturing a battery pack further comprising an adhesive between the inner surface of the pack case and the battery cell assembly.

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