Battery pack and energy storage system comprising the same

Abstract

The battery pack of the present invention comprises: at least one cell assembly including a plurality of battery cells; an enclosure housing the cell assembly having an insertion portion along its length, the insertion portion having an outer surface recessed inwardly; and a rod-shaped reinforcing member inserted into the insertion portion.

Description

Technology Field

[0001] The present invention relates to a battery pack and an energy storage system including the same, and more specifically, to a battery pack and an energy storage system including the same in which the enclosure and the assembly method between components are improved. Background Technology

[0002] Secondary batteries, which possess electrical characteristics such as high energy density and high applicability across product groups, are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) driven by electric power sources. These secondary batteries are attracting attention as an energy source for enhancing eco-friendliness and energy efficiency, not only for the primary advantage of drastically reducing the use of fossil fuels but also because they generate no by-products from energy use.

[0003] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, or unit battery cells, is approximately 2.5V to 4.2V. Therefore, if a higher output voltage is required, multiple battery cells are connected in series to form a battery pack. Additionally, depending on the charge / discharge capacity required for the battery pack, multiple battery cells are connected in parallel to form a battery pack. Accordingly, the number of battery cells included in the battery pack can be set in various ways depending on the required output voltage or charge / discharge capacity.

[0004] Energy Storage Systems (ESS), which have recently been attracting attention, are devices that maximize power usage efficiency by storing generated electricity in battery packs and supplying it to consumers when needed. In an ESS, multiple battery packs form a single battery rack, and dozens to hundreds of battery racks are combined to constitute a single system. It is also used in conjunction with UPS (Uninterruptible Power Supply) systems, which ensure stable power supply in response to sudden power interruptions or anomalies, and solar power generation systems, which convert sunlight into electrical energy. Furthermore, as the commercialization of electric vehicles accelerates, such ESS can also be applied to electric charging stations capable of charging these vehicles.

[0005] In the case of battery packs used in ESS, they can be configured in a form in which multiple battery cells are housed in an outer casing, which can be called a pack case. Here, the outer casing of an ESS battery pack is usually manufactured from a high-rigidity metal material, usually steel, to support the heavy load of multiple battery cells.

[0006] However, in this case, electrical insulation between the enclosure and electrical components, particularly between the enclosure and the battery cells, becomes an issue. To resolve this, additional insulation structures or separate insulation components must be applied between the enclosure and the battery cells. Consequently, this leads to problems such as increased manufacturing labor, tact time, and production costs for the battery pack.

[0007] Meanwhile, conventional ESS battery packs have a structure that uses bolt-nut connections to secure internal pack components. Additionally, when assembling terminal blocks, bolts are fastened to prevent rotation due to torque and to secure the terminal block position, thereby preventing both fixation and rotation.

[0008] When using conventional bolts and nuts, structural considerations are required to implement them; for instance, the design must take into account the avoidance of inserts or undercuts. Furthermore, the design must also account for potential insulation weakening issues that may arise. Additionally, from a process management perspective, bolts and nuts require continuous monitoring and management of torque for fastening, prevention of missed fastenings, and loosening due to product use after fastening. There is also the issue of increased takt time due to the addition of processes for fastening and verification.

[0009] Therefore, there is a need for technological development regarding enclosure structures with enhanced structural rigidity and safety to ensure electrical insulation between the enclosure and electrical components while simultaneously providing robust support for multiple battery cells. Additionally, there is a need for technological development regarding battery packs that require fewer design variables to consider for securing internal pack components compared to the use of bolts and nuts. The problem to be solved

[0010] The present invention was conceived in consideration of the aforementioned problems, and the objective of the present invention is to provide a battery pack with secured electrical insulation and structural safety, and an energy storage system including the same.

[0011] Another problem that the present invention aims to solve is to provide a battery pack and an energy storage system including the same, which has fewer design variables to consider for securing internal pack components compared to when using bolts and nuts, is easier to manage in terms of process control compared to when using bolts and nuts, and does not increase the takt time. means of solving the problem

[0012] A battery pack of the present invention for solving the above-mentioned problem comprises: at least one cell assembly including a plurality of battery cells; an outer casing for housing the cell assembly, having an insertion portion along the longitudinal direction in which the outer surface is formed in a shape recessed inwardly; and a rod-shaped reinforcing member inserted into the insertion portion.

[0013] The above-described enclosure includes a base plate on which the battery cell is seated; and support frame portions provided on both sides of the base plate and constituting the insert portion.

[0014] The base plate and the support frame can be injection molded as a single unit.

[0015] The above reinforcing member may be a pair of steel pipes.

[0016] The above outer casing is made of plastic material, and the above reinforcing member may be made of metal material.

[0017] The battery pack of the present invention may further include a base clip for fixing the position of the reinforcing member.

[0018] The above at least one cell assembly is a plurality of cell assemblies arranged side by side with each other, and the cell assembly may include a busbar frame assembly.

[0019] The support frame portion of the base plate may be provided in a border area extending in the arrangement direction of the cell assembly and may be arranged to support the busbar frame assembly of each cell assembly by protruding upward at predetermined intervals along the arrangement direction of the cell assembly.

[0020] The base plate further includes a recess provided between adjacent support frame portions, and the busbar frame assembly of each cell assembly includes a busbar frame made of an electrically insulating material, and the busbar frame may include a mounting plate disposed on the upper surface of the support frame portion; and a seating guide block protruding downward from the mounting plate so as to be inserted into the corresponding recess.

[0021] The above mounting plate and the above seating guide block can be integrally injection molded into the above busbar frame.

[0022] The above-mentioned concave portion includes a step on its upper surface, and the lower surface of the above-mentioned seating guide block may have a shape corresponding to the step.

[0023] When the cell assembly is seated on the base plate by inserting each of the seating guide blocks into the corresponding concave portions, each of the seating guide blocks and the support frame portions are configured to form a continuous assembly wall along the arrangement direction of the cell assembly, and the assembly wall may define the insertion portion.

[0024] The above-mentioned seating guide block and the above-mentioned support frame portion constrain the position of the reinforcing member in the longitudinal and height directions of the reinforcing member, and the outer casing and the busbar frame assembly can be fixed to each other by the reinforcing member.

[0025] The above-described assembly wall includes an upper receiving wall, a lower receiving wall, and a side receiving wall, and the reinforcing member is a rectangular steel pipe, the upper part of the steel pipe is in contact with the upper receiving wall, the lower part of the steel pipe is in contact with the lower receiving wall, and one side of the steel pipe may be in contact with the side receiving wall.

[0026] The above enclosure further includes a front plate on at least one side of the base plate, and the battery pack further includes a terminal block, and a front cover with a snap-fit ​​structure that prevents the terminal block from detaching may be mounted on the front plate.

[0027] The base plate and the front plate can be injection molded as a single unit.

[0028] The front plate is in the form of a vertical plate provided on one edge of the base plate, and the terminal block is mounted on the outer surface of the front plate, and the battery pack further includes a top cover having an opening formed therein, and the terminal block can be exposed or shielded using the front cover which is detachably provided to the front plate through the opening of the top cover.

[0029] The present invention provides an energy storage system characterized by including at least one battery pack according to the present invention as an energy storage system. Effects of the invention

[0030] According to one aspect of the present invention, insulation between the outer casing and the battery cell can be ensured by manufacturing the outer casing from a plastic injection molded product, and structural stability can be ensured by inserting a reinforcing member into the outer casing to improve the mechanical properties of the outer casing.

[0031] In particular, according to one aspect of the present invention, a battery pack configured to achieve perfect insulation by applying an injection-molded enclosure without separate insulating components can be provided. Accordingly, electrical insulation between the enclosure and the battery cells is possible without additional insulation structures or separate insulating components, thereby enabling a reduction in the manufacturing effort, takt time, and manufacturing costs of the battery pack.

[0032] In addition, according to one aspect of the present invention, the enclosure and the busbar frame assembly are fixed to each other by reinforcing members to provide a rigid fastening configuration, thereby improving resistance to bending or sagging.

[0033] Furthermore, through a fixing configuration using reinforcing members, the fixing structure using bolts and nuts can be minimized. Accordingly, in particular, the present invention proposes a structure for structurally assembling and fixing internal components by minimizing the fixing structure using bolts and nuts in a battery pack. According to the present invention, design and management parameters of the battery pack can be minimized, thereby suppressing the occurrence of problems that may arise. That is, compared to when bolts and nuts are used, there are fewer design variables to consider for fixing internal pack components, and it is easier to manage in terms of process control and does not increase the takt time, thereby providing a battery pack.

[0034] According to the present invention, material costs are reduced due to structural simplification and a reduction in the number of parts. According to the present invention, productivity is improved due to a reduction in takt time. According to the present invention, there is also an effect of reducing the weight of the battery pack through process simplification and structural simplification. According to the present invention, since the outer casing is made of plastic injection molding rather than steel, it is not only lightweight, but further weight reduction is possible because, compared to conventional bolt-nut structures, it eliminates the need for the weight of bolts and nuts and the resin required to implement the injection molding structure for fixation.

[0035] As such, according to the present invention, the reinforcing member has a significant effect of reinforcing the rigidity of a base plate manufactured by injection molding, and can stably fix a cell assembly to the base plate and provide a battery pack configured to reduce the weight of the battery pack.

[0036] And by including such battery packs, the energy storage system can be safe, easy to transport and install, and reduce production costs. Brief explanation of the drawing

[0037] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is a perspective view of a battery pack according to one embodiment of the present invention. Figure 2 is a drawing of the top cover separated from the battery pack of Figure 1. Figure 3 is a partially exploded perspective view showing the main parts of the battery pack of Figure 1. FIG. 4 is a perspective view illustrating a cell assembly of a battery pack according to one embodiment of the present invention. FIG. 5 is a perspective view illustrating a base plate and a reinforcing member of a battery pack according to one embodiment of the present invention. Figure 6 is a partial enlarged view of Figure 5. Figure 7 is a drawing showing the busbar frame of Figure 4 in more detail. FIGS. 8 and 9 are drawings illustrating an assembly process or assembly structure of a base plate and a plurality of cell assemblies according to an embodiment of the present invention. Figure 10 is a drawing showing the state in which the base clip is assembled after the reinforcing member is inserted in Figure 9. Figure 11 is a cross-sectional view of the battery pack of Figure 1. FIG. 12 is a drawing illustrating a terminal block portion of a battery pack according to one embodiment of the present invention. FIG. 13 is a drawing for explaining the terminal block assembly and fixing structure in a battery pack according to the present invention. FIG. 14 corresponds to the AA' section of FIG. 13 and is a drawing after the front cover has been assembled. FIG. 15 is a schematic diagram of an energy storage system according to the present invention. Specific details for implementing the invention

[0038] 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, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Accordingly, the embodiments described in this specification and the configurations illustrated in the drawings are merely some of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention; therefore, it should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application.

[0039] FIG. 1 is a perspective view of a battery pack according to one embodiment of the present invention, FIG. 2 is a view with the top cover separated from the battery pack of FIG. 1, and FIG. 3 is a partially exploded perspective view showing the main parts of the battery pack of FIG. 1.

[0040] Referring to FIGS. 1 to 3, the battery pack (10) according to the present invention may be a three-dimensional structure having a predetermined length, width, and height in the X-axis, Y-axis, and Z-axis directions, respectively. The battery pack (10) includes a cell assembly (CMA, 100), an outer casing (400), and a reinforcing member (500). The battery pack (10) may further include a base clip for fixing the position of the reinforcing member (500) and a top cover (410).

[0041] A battery pack (10) according to the present invention comprises one or more cell assemblies (100). Here, the cell assembly (100) refers to a plurality of grouped battery cells (101).

[0042] The battery pack (10) may be configured to include a plurality of cell assemblies (100). For example, as in the embodiment of FIG. 2, the battery pack (10) may include four cell assemblies (100) arranged side by side. The battery pack (10) includes an enclosure (400) to protect the four cell assemblies (100) from the outside.

[0043] The outer casing (400) is a part that accommodates the cell assembly (100). When the top cover (410) is attached to the outer casing (400) as shown in FIG. 1, an empty space can be formed inside which the cell assembly (100) is accommodated, and the cell assembly (100) can be accommodated in this empty space.

[0044] The enclosure (400) can support the cell assembly (100). In particular, the enclosure (400) can primarily support the lower surface of the cell assembly (100). This enclosure (400) can be mounted on a machine or structure that uses the battery pack (10) as an energy source. For example, the enclosure (400) can be mounted on an energy storage system or an electric vehicle.

[0045] In this embodiment, the enclosure (400) may include a base plate (420) that supports the cell assembly (100) at the bottom of the four cell assemblies (100). The base plate (420) supports the cell assembly (100) and constitutes a main part of the enclosure (400). Specifically, the base plate (420) may cover the lower surface of the cell assembly (100).

[0046] The top cover (410) primarily covers the upper surface of the cell assembly (100) and is coupled to the base plate (420). The top cover (410) is provided in the shape of a rectangular box with an open bottom, and the base plate (420) can be provided in the shape of a roughly plate having an area capable of supporting a plurality of cell assemblies (100).

[0047] In particular, the base plate (420) and the top cover (410) each include two unit parts arranged to extend in one direction (in this embodiment, the Y-axis direction), and can be provided by connecting each unit part to each other. FIG. 3 illustrates the parts located on the left among the two unit parts. In addition, on one side where the unit parts face each other, a fastening protrusion protruding in a direction facing each other and a fastening receiving groove that engages with such a fastening protrusion are provided, so that the unit parts can be assembled without a step at the connection point between the unit parts. When manufacturing a large-capacity battery pack, if the size of the outer casing (400) is enlarged, manufacturing difficulties or inconveniences may occur during the handling process. According to this embodiment of the present invention, each unit part of the base plate (420) and the top cover (410) can be manufactured in an appropriate size and completed by assembling them in a simple manner, thus providing the advantage of convenience during the manufacturing and handling process. Furthermore, the base plate (420) can further improve structural rigidity at the connection points of each unit part and has the effect of further improving resistance to bending or sagging in the thickness direction (Z-axis direction).

[0048] Next, the detailed configuration of the cell assembly (100) will be described with reference to FIG. 4.

[0049] FIG. 4 is a perspective view illustrating a cell assembly of a battery pack according to one embodiment of the present invention.

[0050] Referring further to FIG. 4, the cell assembly (100) may include a plurality of battery cells (101). The battery cells (101) may be assembled in a predetermined number to form a single cell assembly (100).

[0051] Each cell assembly (100) may include a cell stack (110, 120) comprising a plurality of battery cells (101). Preferably, the cell stacks (110, 120) are spaced apart by a predetermined distance and have an air layer (K1).

[0052] The number of battery cells (101) forming the cell stack (110, 120) can be varied according to the required output voltage or charge / discharge capacity. A single cell assembly (100) may be configured to include two cell stacks (110, 120) as illustrated, or to include three or four cell stacks. Of course, it may also be possible to include only one cell stack. Here, the cell stack refers to a collection of battery cells (101) formed by stacking a predetermined number of battery cells (101) having a roughly plate-like shape.

[0053] The air layer (K1) can serve to block the transfer of heat between cell stacks (110, 120). For example, when a thermal runaway event occurs in one of the battery cells (101) of the cell stacks (120), the transfer of heat from one cell stack (120) to the other cell stack (110) can be prevented due to the air layer (K1). Therefore, when a thermal event occurs in a specific battery cell (101), the sequential propagation of heat to all battery cells (101) included in the cell assembly (100) can be blocked. Additionally, the air layer (K1) can be used as a passage for gas when gas is generated in the battery cell (101).

[0054] The battery cell (101) may be composed of a pouch-type secondary battery and may be provided in multiple numbers and electrically connected to each other. For electrical connection, the cell assembly (100) includes a busbar frame assembly (300).

[0055] Each battery cell (101) may include an electrode assembly, a battery case housing the electrode assembly, and an electrode lead (102) that protrudes out of the battery case and is electrically connected to the electrode assembly. The electrode lead (102) may include a positive lead and a negative lead, wherein the positive lead is connected to the positive plate of the electrode assembly and the negative lead is connected to the negative plate of the electrode assembly.

[0056] In the illustrated example, each battery cell (101) includes a pair of electrode leads (102) that protrude on each side along its length direction (X-axis direction). In other words, the electrode leads (102) can be provided on the front and rear portions along the length direction of the battery cell (101), which is a pouch-type secondary battery.

[0057] In this embodiment, the cell stack (110, 120) is an assembly of a plurality of battery cells (101) stacked in one direction (Y-axis direction). The battery cells (101) can be arranged side by side in a horizontal direction (Y-axis direction) while standing upright in an up-and-down direction (Z-axis direction). That is, the wide surface of the battery cells (101) can be provided in a form stacked in a horizontal direction with the wide surface standing vertically to the ground.

[0058] The busbar frame assembly (300) is positioned at the front and rear of the cell stacks (110, 120), which are spaced apart by a predetermined distance in the left-right direction (Y-axis direction) and arranged parallel to each other. In other words, the busbar frame assembly (300) is positioned at the front and rear of the cell stacks (110, 120), which are in a direction intersecting the stacking direction of the battery cells (101).

[0059] The busbar frame assembly (300) can be configured to correspond to the number of cell stacks. That is, the busbar frame assembly (300) of the present embodiment is designed to correspond to two cell stacks (110, 120), but, for example, if the number of cell stacks is three, the busbar frame assembly (300) can also be configured to support and electrically connect the three cell stacks.

[0060] The busbar frame assembly (300) includes a busbar frame (310) and a plurality of busbars (320).

[0061] The busbar frame (310) is made of an electrically insulating material and can be provided in a size that integrally covers the front surface or the rear surface of the cell stack (110, 120). Additionally, the busbar frame (310) may be provided with lead slits that allow a predetermined number of electrode leads (102) to pass through in the front-rear direction (X-axis direction). The lead slits may be provided at predetermined intervals along the stacking direction of the battery cell (101).

[0062] A plurality of busbars (320) may be provided in the form of rods or plates made of a metal material having electrical conductivity, such as copper, aluminum, or nickel. These plurality of busbars (320) may be mounted on a busbar frame (310) at regular intervals apart from each other along the stacking direction of the battery cells (101).

[0063] The battery cells (101) constituting each of the cell stacks (110, 120) may have their electrode leads (102) drawn out to the outside of the busbar frame (310) by passing through the corresponding lead slit. The electrode leads (102) drawn out to the outside of the busbar frame (310) may be bent and fixedly attached to the surface of the corresponding busbar (320). For example, the busbar (320) and the electrode leads (102) may be fixedly joined to each other by laser welding or ultrasonic welding. For example, the positive leads of two battery cells (101) are stacked and attached to a specific busbar (320), and the negative leads of two other battery cells (101) are stacked and attached to the specific busbar (320). Then, four battery cells (101) can be connected in series and / or parallel with each other. In this way, if the electrode leads (102) of the battery cells (101) are attached to the corresponding busbar (320), all battery cells (101) included in the cell stack (110, 120) can be connected in series and / or in parallel.

[0064] The busbar frame (310) can achieve electrical insulation. The busbar frame (310) can be manufactured as a plastic structure through injection molding, so no separate insulation treatment or insulation parts are required for electrical insulation. It also helps with weight reduction.

[0065] In addition, it is preferable that it be configured as an injection structure for implementing a mating part with the base plate (420). In the battery pack (10) according to the present embodiment, the busbar frame (310) of the busbar frame assembly (300) may further include a mounting plate (314) that is seated on the upper surface of the support frame portion (422) of the base plate (420) and a seating guide block (315) that protrudes downward from the mounting plate (314). The mounting plate (314) and the seating guide block (315) are components for increasing the assembly and fixation between the plurality of cell assemblies (100) and the base plate (420). The mounting plate (314) and the seating guide block (315) may be injection molded integrally with the busbar frame (310). The mounting plate (314) and the seating guide block (315) will be described in more detail below in conjunction with the base plate (420).

[0066] Referring again to FIGS. 1 to 3, the outer casing (400) may be made of plastic material. The outer casing (400) may be made entirely of plastic material. In particular, the outer casing (400) may be formed in the form of a plastic injection molded product. In this way, if the outer casing (400) is manufactured as a plastic injection molded product, insulation from the battery cell (101) can be ensured.

[0067] A plurality of cell assemblies (100) may be seated and supported on the base plate (420). In the illustrated example, four cell assemblies (100) with electrode leads (102) protruding in both directions of the X-axis are arranged side by side along the Y-axis, and a busbar frame assembly (300) connecting the electrode leads (102) in the cell assemblies (100) is placed on both sides of the base plate (420). If the cell assemblies include electrode leads protruding in one direction of the X-axis, the busbar frame assembly may be placed on one side of the base plate.

[0068] In particular, the base plate (420) can achieve electrical insulation and is preferably configured as an injection molded structure for implementing the cell assembly (100) and mating part. The base plate (420) can be manufactured as a plastic structure through injection molding, so no separate insulation treatment or insulating parts are required for electrical insulation. In addition, it can be made lighter than when the outer casing is constructed of metal material.

[0069] Conventional battery pack enclosures are manufactured by extrusion or made of rigid materials such as steel plates. This presents a problem of increased weight and cost because additional insulating components must be applied for insulation. Since the battery pack (10) according to the present invention uses an injection-molded enclosure, there is no need to apply additional insulating components. Therefore, weight and cost can be reduced.

[0070] However, when applied as a plastic injection molded product, the structural safety of the outer casing (400) may be an issue. Furthermore, as the size of the outer casing (400) increases, the structure of the plastic injection molded outer casing (400) may experience more bending or sagging compared to the conventional outer casing made of steel, and may be weaker in terms of strength or rigidity, so there may be a limit to the robust support capacity.

[0071] Accordingly, in this embodiment, a reinforcing member (500) is provided in the outer casing (400). That is, the structural rigidity of the injection-molded outer casing is supplemented by a reinforcing member (500), which may be a steel pipe for mechanical structures. The reinforcing member (500) can sufficiently supplement the desired rigidity with less volume and weight compared to the steel base plate of a conventional battery pack outer casing. Therefore, the battery pack (10) according to the present invention can reduce weight and cost compared to a conventional battery pack.

[0072] The outer casing (400) is provided with an insertion portion (424a) along the longitudinal direction, which is formed in a shape where the outer surface is recessed inward. In particular, the insertion portion (424a) may be provided on both sides of the base plate (420) of the outer casing (400), and the base plate (420) includes a support frame portion (422) to enable the formation of such an insertion portion (424a). The base plate (420) and the support frame portion (422) can be injection molded as a single unit. By manufacturing the outer casing (400) as a plastic injection molded product in this manner, the advantage of ensuring insulation from the battery cell (101) is secured, as well as convenience in processing and a reduction in the number of manufacturing steps. Thus, by manufacturing the outer casing (400) as a plastic injection molded product, electrical insulation is possible without additional insulation structures or separate insulation parts, thereby enabling a reduction in the takt time and manufacturing cost of the battery pack (10).

[0073] The reinforcing member (500) can be inserted into the outer casing (400). The reinforcing member (500) can be inserted into the insertion part (424a) of the outer casing (400). In particular, the reinforcing member (500) can be configured as a rod shape that is extended in one direction in order to be inserted into the insertion part (424a). The insertion part (424a) can be provided on both sides of the outer casing (400). Thus, the reinforcing member (500) can be inserted from the side of the battery pack (10). Since the insertion part (424a) is provided in a shape where the outer surface of the outer casing (400) is recessed inward, the reinforcing member (500) can be easily inserted into the insertion part (424a) by a simple operation of pushing it inward from the outer surface of the outer casing (400), that is, in the side direction.

[0074] The reinforcing member (500) may be made of a metal material. For example, the reinforcing member (500) may be a pair of steel pipes. Also, as shown in FIG. 3, the reinforcing member (500) may be a rectangular steel pipe with a square cross-section. Additionally, the reinforcing member (500) may be provided in the form of a hollow pipe as shown. In this case, the weight can be further reduced.

[0075] A pair of such reinforcing members (500) can be arranged to be inserted into the insertion portion (424a) of the outer casing (400). Through this, both sides of the outer casing (400) can be firmly supported. Thus, even though the outer casing (400) is manufactured as a plastic injection molded product, the mechanical properties of the outer casing (400) are improved through the reinforcing members (500), thereby ensuring structural stability. Compared to the case where the cell assembly (100) is supported only by the base plate (420), through the reinforcing members (500), the entire combined structure can support the load of the cell assembly (100), thereby ensuring structural safety.

[0076] FIG. 5 is a perspective view illustrating a base plate and a reinforcing member of a battery pack according to one embodiment of the present invention, and FIG. 6 is a partial enlarged view of FIG. 5.

[0077] First, as shown in FIG. 5, the base plate (420) may have a lower venting hole (425) formed through it. Also, as shown in FIG. 1 and FIG. 2, the top cover (410) may have an upper venting hole (411) formed through it. The upper venting hole (411) and the lower venting hole (425) may be formed to have a vertically symmetrical structure. Furthermore, the upper venting hole (411), the air layer (K1) shown in FIG. 2 and FIG. 3, and the lower venting hole (425) may all be configured to match in the vertical direction. Gas ejected from the battery cell (101) may be discharged to the outside of the battery pack (10) through the air layer (K1) and / or the upper venting hole (411) and / or the lower venting hole (425). In this way, the high-temperature, high-pressure gas generated from the battery cells (101) can be uniformly dispersed and discharged to the outside of the outer casing (400). Accordingly, the collapse or deformation of the battery pack (10) can be prevented when gas is ejected from the battery cells (101).

[0078] Meanwhile, as illustrated in FIGS. 5 and 6, the support frame portion (422) of the base plate (420) is provided in a border area extending in the arrangement direction of the cell assembly (100) and protrudes upward at predetermined intervals along the arrangement direction of the cell assembly (100). Additionally, the base plate (420) may further include a concave portion (423) provided between adjacent support frame portions (422). Here, the arrangement direction of the cell assembly (100) is the same as the stacking direction of the battery cell (101), and the border area extending in the arrangement direction of the cell assembly (100) includes border areas in both directions of the X-axis in the base plate (420) of FIG. 5.

[0079] Additionally, the support frame portion (422) has a shape in which the outer surface is recessed inward, so that it can form an insertion portion (424a). The recessed shape is provided in a roughly 'C' shape, and this shape can be matched with the reinforcing member (500). Meanwhile, the recessed shape does not necessarily have to be in a 'C' shape as long as it is matched with the reinforcing member (500). The concave portion (423) can be located between two adjacent support frame portions (422), as shown in FIG. 6.

[0080] FIG. 7 is a drawing illustrating the busbar frame of FIG. 4 in more detail. FIG. 8 and FIG. 9 are drawings illustrating the assembly process or assembly structure of a base plate and a plurality of cell assemblies according to an embodiment of the present invention. FIG. 10 is a drawing showing the state in which the base clip is assembled after the reinforcing member is inserted in FIG. 9.

[0081] The concave portion (423) can be configured to be shaped to match the mounting guide block (315) of the busbar frame (310), as shown in FIGS. 7 and 8. In particular, the concave portion (423) may include a step on its upper surface, and the lower surface of the mounting guide block (315) may have a shape that corresponds to the step. The step can implement a position guide and may be configured to specifically include an inclined portion to facilitate position guide and assembly of the guide block (315) in the concave portion (423). Accordingly, the cell assembly (100) can be stably mounted and stored on the base plate (420).

[0082] Next, referring further to FIGS. 8 to 10, the assembly structure and fixing structure between the base plate (420) and the plurality of cell assemblies (100) will be described.

[0083] Each cell assembly (100) includes a busbar frame assembly (300) equipped with a seating guide block (315), and the base plate (420) is equipped with a recess (423) at regular intervals. The number of seating guide blocks (315) provided in the cell assembly (100) and the number of recesses (423) provided in the base plate (420) are the same.

[0084] A support frame portion (422) is protruding around the concave portion (423). A seating guide block (315) can be fitted into the concave portion (423) by passing between adjacent support frame portions (422) from top to bottom, that is, in the Z-axis direction. The concave portion (423) can be configured in the edge area of ​​the base plate (420) so that when the seating guide block (315) of each cell assembly (100) is inserted into the corresponding concave portion (423), the cell assembly (100) is spaced apart from each other on the base plate (420). Additionally, the busbar frame (310) of each cell assembly (100) is provided with a mounting plate (314) that can be positioned facing the upper surface of the support frame portion (422), as shown in FIGS. 3 and 7.

[0085] The battery pack (10) according to the present invention includes the above configuration, so that when each cell assembly (100) is assembled to the base plate (420) such that the seating guide block (315) and the concave portion (423) fit together, a plurality of cell assemblies (100) can be easily positioned in the correct position relative to the base plate (420), as shown in FIG. 8.

[0086] Additionally, each cell assembly (100) can be fixed in the Y-axis direction with respect to the base plate (420) in FIG. 8 because the seating guide block (315) is inserted so as to fit into the recess (423) between the two support frame parts (422). In other words, the seating guide block (315) of the busbar frame (310) is inserted into the recess (423) of the base plate (420), and the support frame part (422) is protruded around the recess (423) so as to be constrained to the left and right sides (Y-axis direction) of the recess (423), so that after each cell assembly (100) is seated on the base plate (420), movement in the Y-axis direction is restricted.

[0087] Referring to FIG. 9, when the cell assembly (100) is seated on the base plate (420) with each seating guide block (315) inserted into a corresponding recess (423), each seating guide block (315) and the support frame (422) can be configured to form a continuous assembly wall (424) along the arrangement direction of the cell assembly (100). That is, the seating guide block (315) and the support frame (422) can be arranged so that a certain internal space is mutually communicated with each other, and can also be arranged so that a certain internal space is mutually communicated with adjacent seating guide blocks (315) and support frame (422), and a reinforcing member (500) can be inserted and arranged within this space.

[0088] The assembled wall (424) can be formed such that its outer surface is recessed inward, thereby defining the insertion part (424a) of the enclosure (400). As shown in FIG. 9, a reinforcing member (500) can be inserted into the insertion part (424a) from the side.

[0089] The reinforcing member (500) may be provided in a rod shape having a length corresponding to the length of the assembled wall (424). Such reinforcing member (500) may be applied substantially equally to both edge areas of the base plate (420).

[0090] More specifically, the assembled wall (424) includes an upper receiving wall (424_1), a lower receiving wall (424_2), and a side receiving wall (424_3), and the reinforcing member (500) is a rectangular steel pipe. The upper part of the reinforcing member (500) is in contact with the upper receiving wall (424_1), the lower part of the reinforcing member (500) is in contact with the lower receiving wall (424_2), and one side of the reinforcing member (500) may be in contact with the side receiving wall (424_3).

[0091] The upper receiving wall (424_1) formed by the support frame part (422) of the base plate (420) and the upper receiving wall (424_1) formed by the seating guide block (315) of the busbar frame (310) are formed parallel to each other and have no step difference. The lower receiving wall (424_2) formed by the support frame part (422) and the lower receiving wall (424_2) formed by the seating guide block (315) are also formed parallel to each other and have no step difference. The side receiving wall (424_3) formed by the support frame part (422) and the side receiving wall (424_3) formed by the seating guide block (315) are also formed parallel to each other and have no step difference. Accordingly, the internal space formed by the assembly wall (424) is interconnected in the X-axis, Y-axis, and Z-axis directions to define an insertion part (424a) of the integrated space, and accordingly, a reinforcing member (500) can be stably inserted into the insertion part (424a). Furthermore, after being inserted into the insertion part (424a), the position of the reinforcing member (500) is constrained in the X-axis, Y-axis, and Z-axis directions.

[0092] Meanwhile, as shown in FIG. 10, a base clip (510) can be mounted on the base plate (420) so that the reinforcing member (500) does not easily come out of the insertion part (424a). For example, after the reinforcing member (500) is inserted into the insertion part (424a), the base clip (510) can be coupled to the support frame part (422) of the base plate (420). The base clip (510) is for fixing the reinforcing member (500) to the base plate (420) and may be a bracket structure made of steel.

[0093] According to this embodiment, all cell assemblies (100) can be fixed to the base plate (420) in the X-axis, Y-axis, and Z-axis directions. That is, each cell assembly (100) is sandwiched between the support frame portions (422) (both edge areas) of the base plate (420), thereby restricting movement in the X-axis direction. Since the support frame portions (422) and the seating guide block (315) are fixed by the reinforcing member (500), the movement of the seating guide block (315) in the Y-axis and Z-axis directions is restricted. Subsequently, the battery pack (10) can be completed by further assembling the top cover (410) to prevent movement of the reinforcing member (500) in a secondary manner.

[0094] FIG. 11 is a cross-sectional view of the battery pack of FIG. 1. A cross-section perpendicular to the Y-axis direction is shown.

[0095] As shown in FIG. 11, the reinforcing member (500) is inserted into the inner side of the seating guide block (315) of each cell assembly (100), thereby restricting movement in the X-axis and Z-axis directions. Also, as described above, the seating guide block (315) of each cell assembly (100) is inserted into the concave portion (423), thereby restricting movement in the Y-axis direction. In this way, the seating guide block (315) and the support frame portion (422) also constrain the position of the reinforcing member (500) in the length direction and height direction of the reinforcing member (500).

[0096] Additionally, since the reinforcing member (500) is inserted through the support frame portion (422) of the base plate (420) and the seating guide block (315) of the busbar frame (310) of the cell assembly (100), the reinforcing member (500) can fix the base plate (420) and the cell assembly (100). That is, the outer casing (400) and the busbar frame assembly (300) can be fixed to each other by the reinforcing member (500). In this way, it can be confirmed that the X-axis direction and Z-axis direction can be constrained using the reinforcing member (500), the base plate (420), and the busbar frame (310) without bolts and nuts.

[0097] In this way, the base plate (420) and the busbar frame (310) can be manufactured as plastic structures through injection molding, and the base plate (420) and the busbar frame (310), which are divided into two parts, are assembled and fixed to each other by inserting a reinforcing member (500) and fixing the sides. The base plate (420) and the busbar frame (310) can be joined without bolts and nuts, and structural safety can be reinforced.

[0098] From a process management perspective, bolts and nuts require continuous monitoring and management regarding torque for fastening, failure to check for missed fastenings, and loosening due to product use after fastening. There is also the issue of increased takt time resulting from the addition of processes for fastening and verification. According to the present invention, the use of bolts and nuts can be minimized, making management easier from a process management perspective without increasing takt time.

[0099] Meanwhile, referring to FIGS. 2 and 3, the outer casing (400) further includes a front plate (427) on at least one side of the base plate (420), and the battery pack (10) further includes a terminal block (700). A front cover (701) with a snap fit (702) structure that prevents the terminal block (700) from detaching can be mounted on the front plate (427). The front cover (701) is provided to be detachably attached to the front plate (427).

[0100] FIG. 12 is a drawing illustrating a terminal block portion of a battery pack according to an embodiment of the present invention. FIG. 13 is a drawing for explaining the terminal block assembly and fixing structure in a battery pack according to the present invention. FIG. 14 corresponds to the AA' cross-section of FIG. 13 and is a drawing after the front cover has been assembled.

[0101] Referring to FIG. 2 and FIG. 12 to FIG. 14 together, the base plate (420) and the front plate (427) can be injection molded as a single unit.

[0102] The front plate (427) is a vertical plate-shaped plate provided on one edge of the base plate (420) and can serve as an electrical component mounting section. For example, a terminal block (700) may be mounted on the outer surface of the front plate (427), and a BMS assembly (600) may also be mounted. Here, the BMS assembly (600) may be configured to measure the current and temperature of the battery cell (101) within the battery pack (10) and to control the charging and discharging of the battery cell (101). The terminal block (700) may be equipped with electrode terminals of the battery pack (10) and fuses, etc. To mount the BMS assembly (600) and the terminal block (700), a BMS mounting section (600A) and a terminal block mounting section (700A) may be provided on the outer surface of the front plate (427). In particular, the terminal block mounting section (700A) may be configured to include a stepped section (428).

[0103] The top cover (410) may include an opening (412). The terminal block (700) may be exposed or shielded using a front cover (701) that is detachably provided on the front plate (427) through the opening (412) of the top cover (410).

[0104] Referring to FIG. 12, the terminal block (700) can be mounted on the stepped portion (428) of the front plate (427). Conventionally, when assembling the terminal block, bolts are fastened to prevent rotation due to torque and to fix the position of the terminal block, thereby preventing rotation. In the present invention, rotation of the terminal block (700) can be prevented through a structural step, and the front cover (701) of the terminal block (700) can be fixed in position on the front plate (427) through a snap-fit ​​(702) structure.

[0105] The step section (428) provides a position guide during assembly and prevents rotation after assembly through the wall formed by the step. After assembly, the terminal block (700) is prevented from coming off due to the snap-fit ​​(702) structure.

[0106] Conventionally, when assembling terminal blocks, bolts are fastened to prevent rotation due to torque and to fix the position of the terminal blocks, thereby preventing rotation and fixing. According to this embodiment of the present invention, the use of bolts and nuts is minimized by utilizing a stepped portion (428).

[0107] Meanwhile, the front plate (427) may be configured to mount the BMS assembly (600) through an insert nut (610). The front plate (427) may be configured during plastic injection molding so that the BMS assembly (600) can be mounted to the BMS mounting portion (600A) through the insert nut (610) without the need for a separate BMS housing.

[0108] In this way, the front plate (427) can be manufactured by integrally forming the BMS mounting portion (600A) and the terminal block mounting portion (700A) through injection molding. Insulation is satisfied through plastic injection molding, and there is an effect of weight reduction and cost reduction. In addition, there is no need to fasten bolts and nuts to fix the position of the terminal block (700).

[0109] In terms of process management, bolts and nuts require continuous monitoring and management of torque for fastening, whether fastening is omitted, and loosening due to product use after fastening. There is also the problem of increased takt time due to the addition of processes for fastening and fastening verification. According to the present invention, a structure is proposed that structurally assembles and fixes internal components by minimizing the fixing structure using bolts and nuts in a battery pack (10).

[0110] According to the present invention, design and management factors of the battery pack (10) can be minimized to suppress potential problems. That is, compared to when using bolts and nuts, there are fewer design variables to consider for fixing internal pack components, and compared to when using bolts and nuts, it is easier to manage in terms of process control and does not increase the takt time. According to the present invention, material costs are reduced due to structural simplification and a reduction in the number of parts. According to the present invention, productivity is improved due to a reduction in takt time.

[0111] FIG. 15 is a schematic diagram of an energy storage system according to the present invention.

[0112] The energy storage system (20) may include one or more battery packs (10) according to the present invention as described above. In particular, the energy storage system (20) may include a plurality of battery packs (10) according to the present invention in a form electrically connected to each other in order to have a large energy capacity. In addition, the energy storage system (20) according to the present invention may further include various other components of an energy storage system known at the time of filing the present invention. Furthermore, such an energy storage system (20) may be used in various places or devices, such as smart grid systems or electric charging stations.

[0113] For example, the energy storage system (20) may include a plurality of battery racks comprising battery packs (10) according to the present invention. The battery packs (10) may be configured to be accommodated in a rack case (not shown) in a vertically arranged configuration. A plurality of battery packs (10) may be mounted within the rack case, spaced apart from each other in the vertical direction. The rack case may have a storage space having an open structure that allows communication between the plurality of battery packs (10) in the vertical direction. The battery rack may be equipped with a rack BMS (Battery Management System) at the top of the plurality of battery packs (10). Here, the rack BMS may be a battery management system that centrally controls the charging and discharging of the plurality of battery packs (10) provided in the battery rack. Furthermore, these plurality of battery racks may be electrically connected to each other through a rack busbar (not shown).

[0114] The energy storage system (20) according to the present invention includes the battery pack (10) according to the present invention, thereby allowing the advantages of the battery pack (10) to be utilized as is. Since the electrical insulation and structural safety of the battery pack (10) are secured, the energy storage system (20) including it is safe. Since the structural safety of the battery pack (10) is secured and weight is reduced, the transport and installation of the battery pack (10) are easy. Since the material cost of the battery pack (10) is reduced and productivity is improved, the production cost of the energy storage system (20) including it can also be lowered.

[0115] In this specification, terms indicating directions such as up, down, left, right, front, and back have been used; however, these terms are used merely for convenience of explanation, and it is obvious to those skilled in the art that they may vary depending on the location of the object or the position of the observer.

[0116] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs. Explanation of the symbols

[0117] 10: Battery pack 20: Energy storage device 100: Cell assembly 101: Battery cell 102: Electrode lead 110, 120: Cell stack K1 : Air layer 300 : Busbar frame assembly 310 : Busbar frame 314 : Mounting plate 315 : Guide block 320 : Busbar 400 : Enclosure 410 : Top cover 412 : Opening 420 : Base plate 422: Support frame part 423: Concave part 424 : Prefabricated wall 424a : Storage compartment 427: Front plate 428: Stepped section 500 : Reinforcement member 510 : Base clip 700 : Terminal Block 701 : Front Cover 702: Snap Fit

Claims

Claim 1 A battery pack comprising: a plurality of cell assemblies arranged side by side; an outer casing for housing the cell assemblies, having an insertion portion along the longitudinal direction formed such that the outer surface is recessed inwardly; and a rod-shaped reinforcing member inserted into the insertion portion, wherein the cell assemblies comprise a plurality of battery cells and a busbar frame assembly, and the outer casing comprises a base plate on which the battery cells are seated; and a support frame portion provided on both sides of the base plate and constituting the insertion portion, wherein the support frame portion is provided in a rim area extending in the arrangement direction of the cell assemblies and is provided to support the busbar frame assembly of each cell assembly by protruding upward at predetermined intervals along the arrangement direction of the cell assemblies. Claim 2 delete Claim 3 A battery pack according to claim 1, characterized in that the base plate and the support frame are integrally injection molded. Claim 4 A battery pack according to claim 1, characterized in that the reinforcing member is a pair of steel tubes. Claim 5 A battery pack according to claim 1, characterized in that the outer casing is made of plastic material and the reinforcing member is made of metal material. Claim 6 A battery pack according to claim 1, further comprising a base clip for fixing the position of the reinforcing member. Claim 7 delete Claim 8 A battery pack according to claim 1, wherein the base plate further comprises a recess provided between adjacent support frame portions, and the busbar frame assembly of each cell assembly comprises a busbar frame made of an electrically insulating material, and the busbar frame comprises a mounting plate disposed on the upper surface of the support frame portion; and a seating guide block protruding downward from the mounting plate so as to be inserted into the corresponding recess. Claim 9 A battery pack according to claim 8, characterized in that the mounting plate and the seating guide block are integrally injection molded into the busbar frame. Claim 10 A battery pack according to claim 8, wherein the above-mentioned concave portion includes a step on its upper surface, and the lower surface of the above-mentioned seating guide block has a shape corresponding to the step. Claim 11 A battery pack according to claim 8, wherein when the cell assembly is seated on the base plate by inserting each of the seated guide blocks into the corresponding concave portions, each of the seated guide blocks and the support frame portions are configured to form a continuous assembly wall along the arrangement direction of the cell assembly, and the assembly wall defines the insertion portions. Claim 12 A battery pack according to claim 11, wherein the above-mentioned seating guide block and the above-mentioned support frame portion restrain the position of the reinforcing member in the longitudinal and height directions of the reinforcing member, and the above-mentioned outer casing and the above-mentioned busbar frame assembly are fixed to each other by the reinforcing member. Claim 13 A battery pack according to claim 11, wherein the assembly wall comprises an upper receiving wall, a lower receiving wall, and a side receiving wall, and the reinforcing member is a rectangular steel pipe, wherein the upper part of the steel pipe contacts the upper receiving wall, the lower part of the steel pipe contacts the lower receiving wall, and one side of the steel pipe contacts the side receiving wall. Claim 14 A battery pack according to claim 1, wherein the outer casing further includes a front plate on at least one side of the base plate, the battery pack further includes a terminal block, and a snap-fit ​​front cover is mounted on the front plate to prevent the terminal block from detaching. Claim 15 A battery pack according to claim 14, characterized in that the base plate and the front plate are integrally injection molded. Claim 16 A battery pack according to claim 14, wherein the front plate is in the form of a vertical plate provided on one edge of the base plate, and the terminal block is mounted on the outer surface of the front plate, and the battery pack further comprises a top cover having an opening formed therein, wherein the terminal block is exposed or shielded using the front cover which is detachably provided to the front plate through the opening of the top cover. Claim 17 An energy storage system characterized by comprising at least one battery pack according to any one of claims 1, 3 to 6, or 8 to 16.

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