Battery pack and energy storage system including same

Abstract

The battery pack of the present invention includes at least one cell assembly including a plurality of battery cells, an outer casing that houses the cell assembly and has an insertion portion along the longitudinal direction whose outer surface is recessed inward, and a rod-shaped reinforcing member that is inserted into the insertion portion.

Description

[Technical Field]

[0001] The present invention relates to a battery pack and an energy storage system including the same, and more particularly to a battery pack with an improved assembly method between an outer casing and components, and an energy storage system including the same. This application claims priority to Korean Patent Application No. 10-2022-0138105, filed on October 25, 2022, the entire contents of which are incorporated herein by reference in their entirety. [Background technology]

[0002] Secondary batteries, which are easily applicable to a variety of products and have electrical properties 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 driven by electrical sources. These secondary batteries not only have the temporary advantage of dramatically reducing the use of fossil fuels, but also have the advantage of producing no by-products associated with energy use, and are therefore attracting attention as a new energy source that is environmentally friendly and improves energy efficiency.

[0003] Currently widely used types of secondary batteries include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel metal hydride batteries, and nickel zinc batteries. The operating voltage of such a unit secondary battery cell, i.e., a unit battery cell, is approximately 2.5V to 4.5V. Therefore, if a higher output voltage is required, a battery pack may be configured by connecting multiple battery cells in series. Furthermore, depending on the charge / discharge capacity required for the battery pack, a battery pack may be configured by connecting multiple battery cells in parallel. Therefore, the number of battery cells included in the battery pack may be variously set depending on the required output voltage and / or charge / discharge capacity.

[0004] Energy storage systems (ESS), which have been gaining attention recently, are devices that maximize the efficiency of power usage by storing generated electricity in battery packs and supplying it to consumers when it is needed. An ESS consists of multiple battery packs forming a single battery rack, with dozens or even hundreds of battery racks forming a single system. They can also be used in conjunction with uninterruptible power supplies (UPS), which ensure a stable power supply in the event of a sudden power supply interruption or abnormality, and solar power generation systems, which convert sunlight into electrical energy. Furthermore, as electric vehicles become more widely commercialized, ESSs can also be used in EV charging stations and EV charging spots.

[0005] A battery pack used in an energy storage system (ESS) may be formed in a shape in which a plurality of battery cells are housed in an outer casing, which can be referred to as a pack case. Typically, the outer casing of a battery pack for an energy storage system (ESS) is made of a highly rigid metal material, typically steel, to support the high load of the plurality of battery cells.

[0006] However, in this case, electrical insulation between the outer casing and the electrical components, particularly between the outer casing and the battery cells, is problematic, and to solve this, an additional insulating structure or separate insulating parts must be adopted between the outer casing and the battery cells, which increases the number of manufacturing steps for the battery pack, increases the tact time, and raises manufacturing costs.

[0007] On the other hand, battery packs for conventional energy storage systems (ESS) have a structure that uses bolt and nut connections to secure the internal pack components, and also prevent rotation due to torque when assembling the terminal block, and bolts are used to fix the terminal block in place and prevent rotation.

[0008] Conventionally, structural considerations are required when using bolts and nuts to achieve this. For example, design must take into account inserts and the avoidance of undercuts. Furthermore, the design must also take into account the insulation weakening that can occur. From a process management perspective, bolts and nuts require torque management for fastening, and continuous checking and management is required for any loosening or loosening that occurs during use of the fastened product. Another problem is that the additional processes for fastening and checking fastening increase the takt time.

[0009] Therefore, there is a need to develop technology for an outer casing structure that ensures electrical insulation between the outer casing and electrical components, while improving structural rigidity and safety so as to firmly support a plurality of battery cells. There is also a need to develop technology for a battery pack that requires fewer design variables to be considered for fastening internal pack components than when using bolts and nuts. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been made under the above-mentioned background to solve the above-mentioned problems, and an object of the present invention is to provide a battery pack and an energy storage system including the same, in which electrical insulation and structural safety are ensured.

[0011] Another problem to be solved by the present invention is to provide a battery pack and an energy storage system including the same that require fewer design variables to be considered for fastening internal pack components than when using nuts and bolts, are easier to manage from the perspective of process control than when using nuts and bolts, and do not increase takt time. [Means for solving the problem]

[0012] To solve the above-mentioned problems, the battery pack of the present invention includes at least one cell assembly including a plurality of battery cells, an outer casing that houses the cell assembly and has an insertion portion along the longitudinal direction whose outer surface is recessed inward, and a rod-shaped reinforcing member inserted into the insertion portion.

[0013] The outer casing includes a base plate on which the battery cells are mounted, and support frame portions provided on both sides of the base plate and constituting the insertion portion.

[0014] The base plate and the support frame portion may be injection molded together.

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

[0016] The outer housing may be made of a plastic material, and the reinforcing member may be made of a 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 at least one cell assembly may be a plurality of cell assemblies arranged side by side, and the cell assembly may include a bus bar frame assembly.

[0019] The support frame portion of the base plate may be provided in an edge region extending in the arrangement direction of the cell assemblies, and may protrude upward at predetermined intervals along the arrangement direction of the cell assemblies to support the bus bar frame assembly of each of the cell assemblies.

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

[0021] The mounting plate and the mounting guide block may be integrally injection molded with the bus bar frame.

[0022] The recess may include a step on an upper surface, and the lower surface of the mounting guide block may have a shape that matches the step.

[0023] When the cell assembly is placed on the base plate with each of the mounting guide blocks inserted into the corresponding recess, each of the mounting guide blocks and the support frame portion are configured to form a continuous assembly wall along the arrangement direction of the cell assembly, and the assembly wall can limit the insertion portion.

[0024] The mounting guide block and the support frame portion may restrain the position of the reinforcing member in the longitudinal and height directions of the reinforcing member, and the outer casing and the bus bar frame assembly may be fixed to each other by the reinforcing member.

[0025] The assembly wall may include an upper storage wall, a lower storage wall, and a side storage wall, and the reinforcing member may be a rectangular parallelepiped steel pipe, the upper part of which contacts the upper storage wall, the lower part of which contacts the lower storage wall, and one side of which contacts the side storage wall.

[0026] The outer casing may further include a front plate on at least one side of the base plate, and the battery pack may further include a terminal block, and a front cover having a snap-fit ​​structure may be attached to the front plate to prevent the terminal block from coming off.

[0027] The base plate and the front plate may be injection molded together.

[0028] The front plate is a vertical plate provided on one side of the peripheral edge of the base plate, and the terminal block is attached to an outer surface of the front plate. The battery pack further includes a top cover with an opening, and the terminal block may be exposed or shielded by the front cover, which is detachably attached to the front plate through the opening of the top cover.

[0029] An aspect of the present invention provides an energy storage system, characterized in that it includes at least one battery pack according to an aspect of the present invention. [Effects of the Invention]

[0030] According to one aspect of the present invention, the outer casing is manufactured from a plastic injection molding, thereby ensuring insulation between the outer casing and the battery cell, and a reinforcing member is inserted into the outer casing, thereby improving the mechanical properties of the outer casing and ensuring structural stability.

[0031] In particular, according to one aspect of the present invention, a battery pack configured to completely achieve insulation by applying an injection molded outer casing without a separate insulating component can be provided. As a result, electrical insulation between the outer casing and the battery cells can be achieved without an additional insulating structure or separate insulating component, thereby reducing the number of manufacturing steps for the battery pack and saving cycle time and manufacturing costs.

[0032] Furthermore, according to one aspect of the present invention, the outer casing and the bus bar frame assembly are fixed to each other by the reinforcing member to provide a strong fastening structure, thereby improving resistance to warping, bending, or loosening.

[0033] Furthermore, by using a fastening configuration using reinforcing members, the fastening structure using bolts and nuts can be minimized. Therefore, particularly, one aspect of the present invention proposes a structure for structurally assembling and fastening internal components in a battery pack by minimizing the fastening structure using bolts and nuts. According to one aspect of the present invention, it is possible to minimize design and management factors of the battery pack and suppress the occurrence of problems that may occur therein. That is, it is possible to provide a battery pack that requires fewer design variables to be considered for fastening internal pack components than when using bolts and nuts, is easier to manage from the perspective of process management than when using bolts and nuts, and does not increase takt time.

[0034] According to one aspect of the present invention, material costs are reduced by simplifying the structure and reducing the number of parts. According to one aspect of the present invention, productivity is improved by shortening the takt time. According to one aspect of the present invention, the weight of the battery pack is reduced by simplifying the process and the structure. According to one aspect of the present invention, the battery pack is not only lightweight because it uses a plastic injection molding outer casing instead of a steel material, but also, compared to existing structures using bolts and nuts, the weight of the bolts and nuts and the resin required to realize the injection molding structure for fastening are not required, thereby achieving further weight reduction.

[0035] Thus, according to one aspect of the present invention, the reinforcing member has an outstanding effect of reinforcing the rigidity of the base plate manufactured by injection molding, and can stably fix the cell assembly to the base plate, thereby providing a battery pack configured to reduce the weight of the battery pack.

[0036] By including such a battery pack, the energy storage system is safe, easy to transport and install, and can reduce production costs.

[0037] The drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further understand the technical concepts of the present invention as well as the content of the invention, and therefore the present invention should not be interpreted as being limited to only the matters depicted in the drawings. [Brief explanation of the drawings]

[0038] [Figure 1] 1 is a perspective view of a battery pack according to an embodiment of the present invention; [Figure 2] FIG. 2 is a view of the battery pack of FIG. 1 with the top cover removed. [Figure 3] FIG. 2 is a partial exploded perspective view showing the main parts of the battery pack of FIG. 1. [Figure 4] FIG. 2 is a perspective view showing a cell assembly of a battery pack according to an embodiment of the present invention. [Figure 5] 1 is a perspective view showing a base plate and a reinforcing member of a battery pack according to an embodiment of the present invention; [Figure 6] FIG. 6 is a partially enlarged view of FIG. 5. [Figure 7] FIG. 5 is a diagram showing the bus bar frame of FIG. 4 in more detail. [Figure 8] 10A to 10C are diagrams showing an assembly process or assembly structure of a base plate and a plurality of cell assemblies according to one embodiment of the present invention. [Figure 9] 10A to 10C are diagrams showing an assembly process or assembly structure of a base plate and a plurality of cell assemblies according to one embodiment of the present invention. [Figure 10] FIG. 10 is a view showing the assembled state of the base clip after inserting the reinforcing member in FIG. 9. [Figure 11] FIG. 2 is a cross-sectional view of the battery pack of FIG. 1. [Figure 12]FIG. 2 is a diagram showing a terminal block portion of a battery pack according to an embodiment of the present invention. [Figure 13] 10A and 10B are diagrams illustrating an assembly and fixing structure of a terminal block in a battery pack according to an embodiment of the present invention. [Figure 14] 14 corresponds to a cross section taken along the line AA' in FIG. 13, and shows the state after the front cover has been assembled. [Figure 15] FIG. 1 is a schematic diagram of an energy storage system according to one aspect of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0039] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and claims should not be construed as being limited to their ordinary or dictionary meanings, but should be construed as meanings and concepts corresponding to the technical ideas of the present invention, in accordance with the principle that the inventor can appropriately define the concepts of terms himself / herself in order to best describe the invention. Therefore, it should be understood that the embodiment described in this specification and the configuration shown in the drawings are merely a preferred embodiment of the present invention and do not represent the entire technical ideas of the present invention, and therefore, various equivalent and modified embodiments may be available as of the time of filing this application.

[0040] FIG. 1 is a perspective view of a battery pack according to one embodiment of the present invention, FIG. 2 is a view of the battery pack of FIG. 1 with a top cover removed, and FIG. 3 is a partial exploded perspective view showing the main parts of the battery pack of FIG. 1.

[0041] 1 to 3, a battery pack 10 according to an embodiment of 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 and a top cover 410 for fixing the position of the reinforcing member 500.

[0042] A battery pack 10 according to one embodiment of the present invention includes one or more cell assemblies 100. Here, a cell assembly 100 refers to a plurality of battery cells 101 grouped together.

[0043] The battery pack 10 may be configured to include a plurality of cell assemblies 100. For example, as shown in Fig. 2, the battery pack 10 may include four cell assemblies 100 arranged side by side. The battery pack 10 also includes an outer casing 400 for protecting the four cell assemblies 100 from the outside.

[0044] The outer casing 400 is a part that houses the cell assembly 100. When the top cover 410 is coupled to the outer casing 400 as shown in Fig. 1, an empty space for housing the cell assembly 100 can be formed inside, and the cell assembly 100 can be housed in this empty space.

[0045] The outer casing 400 can support the cell assembly 100. In particular, the outer casing 400 can mainly support the lower surface of the cell assembly 100. Such an outer casing 400 can be attached to a machine or mechanism that uses the battery pack 10 as an energy source. For example, the outer casing 400 can be attached to an energy storage system, an electric vehicle, or the like.

[0046] In this embodiment, the outer casing 400 may include a base plate 420 that supports the four cell assemblies 100 from below. The base plate 420 supports the cell assemblies 100 and constitutes a main part of the outer casing 400. Specifically, the base plate 420 may cover the lower surfaces of the cell assemblies 100.

[0047] The top cover 410 mainly covers the upper surface of the cell assembly 100 and is coupled to the base plate 420. The top cover 410 is formed in the shape of a rectangular parallelepiped box with an open bottom, and the base plate 420 may be formed in the shape of a roughly plate-like body having an area large enough to accommodate a plurality of cell assemblies 100.

[0048] In particular, the base plate 420 and the top cover 410 each include two unit parts arranged to extend in one direction (the Y-axis direction in this embodiment), and the unit parts may be connected to each other. FIG. 3 shows the left-side of the two unit parts. The unit parts may have fastening protrusions protruding in opposing directions and fastening receiving grooves coupled to the fastening protrusions on the opposing sides, allowing for smooth assembly at the connection points between the unit parts. When increasing the size of the outer casing 400 to manufacture a large-capacity battery pack, manufacturing it as a single unit may result in difficulties in manufacturing and handling. According to this embodiment of the present invention, the base plate 420 and the top cover 410 can be manufactured to an appropriate size and assembled in a simple manner, resulting in convenient manufacturing and handling. Furthermore, the base plate 420 has the effect of further improving the structural rigidity at the connection points of each unit part, and further improving the resistance to warping, bending or loosening in the thickness direction (Z-axis direction).

[0049] Next, the detailed configuration of the cell assembly 100 will be described with reference to FIG.

[0050] FIG. 4 is a perspective view showing a cell assembly of a battery pack according to one embodiment of the present invention.

[0051] 4, the cell assembly 100 may include a plurality of battery cells 101. A predetermined number of the battery cells 101 may be grouped together to form one cell assembly 100.

[0052] Each cell assembly 100 may include a cell stack 110, 120 including a plurality of battery cells 101. Preferably, the cell stacks 110, 120 are spaced apart by a predetermined distance with an air layer K1 therebetween.

[0053] The number of battery cells 101 constituting the cell stacks 110, 120 can be set variously depending on the required output voltage or charge / discharge capacity. One cell assembly 100 may be configured to include two cell stacks 110, 120 as shown in the figure, or may be configured to include three or four cell stacks. Needless to say, it is also possible for the cell assembly 100 to include only one cell stack. Here, the cell stack refers to an assembly of battery cells 101 in which a predetermined number of roughly plate-shaped battery cells 101 are stacked.

[0054] The air layer K1 can play a role in blocking heat transfer between the cell stacks 110, 120. For example, when a thermal runaway event occurs in one of the battery cells 101 of the cell stack 120, the air layer K1 can prevent heat transfer from one of the cell stacks 120 to the other cell stack 110. Therefore, when a thermal event occurs in a specific battery cell 101, it is possible to block the heat from being transmitted in a chain reaction to all of the battery cells 101 included in the cell assembly 100. The air layer K1 can also be used as a gas transfer path when gas is generated in the battery cell 101.

[0055] The battery cell 101 may be a pouch-type secondary battery, and may be provided in multiples and electrically connected to each other. For electrical connection, the cell assembly 100 includes a bus bar frame assembly 300.

[0056] Each battery cell 101 may include an electrode assembly, a battery case that houses the electrode assembly, and electrode leads 102 that protrude from the battery case and are electrically connected to the electrode assembly. The electrode leads 102 may include a positive electrode lead and a negative electrode lead, and the positive electrode lead may be connected to a positive electrode plate of the electrode assembly, and the negative electrode lead may be connected to a negative electrode plate of the electrode assembly.

[0057] In the illustrated example, each battery cell 101 includes a pair of electrode leads 102 protruding from both sides in the longitudinal direction (X-axis direction) of the battery cell 101. In other words, the electrode leads 102 can be provided at the front and rear portions along the longitudinal direction of the battery cell 101, which is a pouch-type secondary battery.

[0058] In this embodiment, the cell stacks 110, 120 are an assembly of a plurality of battery cells 101 stacked in one direction (Y-axis direction). The battery cells 101 may be arranged in a horizontal direction (Y-axis direction) while standing upright (Z-axis direction). That is, the battery cells 101 may be arranged in a horizontally stacked configuration with their wide surfaces standing vertically to the ground.

[0059] The bus bar frame assemblies 300 are disposed in front of and behind the cell stacks 110 and 120, which are arranged side by side at a predetermined interval in the left-right direction (Y-axis direction). In other words, the bus bar frame assemblies 300 are disposed in front of and behind the cell stacks 110 and 120 in a direction intersecting the stacking direction of the battery cells 101.

[0060] The bus bar frame assembly 300 may be provided to correspond to the number of cell stacks. That is, the bus bar frame assembly 300 of this embodiment is designed to accommodate two cell stacks 110, 120, but if the number of cell stacks is three, for example, the bus bar frame assembly 300 may also be configured to support and electrically connect the three cell stacks.

[0061] The bus bar frame assembly 300 includes a bus bar frame 310 and a plurality of bus bars 320 .

[0062] The bus bar frame 310 may be made of an electrically insulating material and may be sized to cover the front surfaces or rear surfaces of the cell stacks 110, 120. The bus bar frame 310 may also have lead slits that allow a predetermined number of electrode leads 102 to pass through in the front-to-rear direction (X-axis direction). The lead slits may be provided at predetermined intervals along the stacking direction of the battery cells 101.

[0063] The plurality of bus bars 320 may be manufactured in a rod or plate shape from an electrically conductive metal material such as copper, aluminum, nickel, etc. The plurality of bus bars 320 may be attached to the bus bar frame 310 at regular intervals along the stacking direction of the battery cells 101.

[0064] The electrode leads 102 of the battery cells 101 constituting each of the cell stacks 110 and 120 may pass through the corresponding lead slits and be pulled out to the outside of the bus bar frame 310. The electrode leads 102 pulled out to the outside of the bus bar frame 310 may be bent and attached to the surface of the corresponding bus bar 320. For example, the bus bar 320 and the electrode leads 102 may be fixedly coupled to each other by laser welding or ultrasonic welding. For example, the positive electrode leads of two battery cells 101 may be overlapped and attached to a specific bus bar 320, and the negative electrode leads of the other two battery cells 101 may be overlapped and attached to the specific bus bar 320. In this manner, the four battery cells 101 can be connected in series and / or parallel to each other. By attaching the electrode leads 102 of the battery cells 101 to the corresponding bus bar 320 in this manner, all of the battery cells 101 included in the cell stacks 110 and 120 can be connected in series and / or parallel.

[0065] The bus bar frame 310 can achieve electrical insulation. Since the bus bar frame 310 can be manufactured from a plastic structure by injection molding, no separate insulating process or insulating parts are required for electrical insulation. In addition, it helps reduce weight.

[0066] Preferably, the bus bar frame 310 is formed of an injection-molded structure to realize a mating part with the base plate 420. In the battery pack 10 according to this embodiment, the bus bar frame 310 of the bus bar frame assembly 300 may further include a mounting plate 314 mounted on an upper surface of the support frame portion 422 of the base plate 420, and a mounting guide block 315 protruding downward from the mounting plate 314. The mounting plate 314 and the mounting guide block 315 are components for improving the assembly and fixation of the plurality of cell assemblies 100 to the base plate 420. The mounting plate 314 and the mounting guide block 315 may be integrally injection-molded with the bus bar frame 310. The mounting plate 314 and the mounting guide block 315 will be described in more detail below in connection with the base plate 420.

[0067] 1 to 3, the outer casing 400 may be formed from a plastic material. The outer casing 400 may be manufactured entirely from a plastic material. In particular, the outer casing 400 may be formed in the shape of a plastic injection molding. In this way, if the outer casing 400 is manufactured from a plastic injection molding, insulation from the battery cells 101 can be ensured.

[0068] A plurality of cell assemblies 100 can be placed and supported on the base plate 420. In the illustrated example, four cell assemblies 100, each with electrode leads 102 protruding in both directions along the X axis, are aligned along the Y axis, and bus bar frame assemblies 300 that connect the electrode leads 102 in the cell assemblies 100 are placed on both side surfaces of the base plate 420. If the base plate includes a cell assembly with electrode leads protruding in one direction along the X axis, the bus bar frame assembly can be placed on one side surface of the base plate.

[0069] In particular, the base plate 420 is preferably made of an injection-molded structure that can achieve electrical insulation and can be mated with the cell assembly 100. The base plate 420 can be manufactured from a plastic structure by injection molding, eliminating the need for separate insulating treatment or insulating parts for electrical insulation. In addition, it can be made lighter than when the outer casing is made of a metal material.

[0070] Conventionally, the base plate of the outer casing of a battery pack has been manufactured by extrusion or from a rigid material such as a steel plate. This necessitates the use of additional insulating components for insulation, resulting in increased weight and cost. However, the battery pack 10 according to one embodiment of the present invention uses an extruded outer casing, eliminating the need for additional insulating components. This reduces weight and cost.

[0071] However, when plastic injection molding is used, there is a risk of concern about the structural safety of the outer casing 400. Furthermore, as the size of the outer casing 400 increases, warping, bending, and loosening may occur more frequently in the case of the plastic injection molding outer casing 400 structure compared to a conventional steel outer casing, and there is a risk of the strength and rigidity being weakened, so there may be a limit to the strong supporting force.

[0072] For this reason, in this embodiment, the outer casing 400 is provided with a reinforcing member 500. That is, the structural rigidity of the injection molding outer casing is supplemented by the reinforcing member 500, which may be a steel pipe for mechanical structures. The reinforcing member 500 can sufficiently supplement the desired rigidity with a smaller volume and weight than the steel base plate of the outer casing of a conventional battery pack. Therefore, the battery pack 10 according to one aspect of the present invention can reduce weight and cost compared to conventional battery packs.

[0073] The outer casing 400 has an insertion portion 424a formed along the longitudinal direction, with the outer surface recessed inward. In particular, the insertion portion 424a may be provided on both sides of a base plate 420 of the outer casing 400, and the base plate 420 includes a support frame portion 422 to form the insertion portion 424a. The base plate 420 and the support frame portion 422 may be integrally injection molded. Manufacturing the outer casing 400 from a plastic injection molding material has the advantage of ensuring insulation from the battery cells 101, as well as ensuring ease of processing and reducing manufacturing man-hours. Manufacturing the outer casing 400 from a plastic injection molding material enables electrical insulation without the need for additional insulating structures or separate insulating components, thereby shortening the cycle time of the battery pack 10 and reducing manufacturing costs.

[0074] The reinforcing member 500 can be inserted into the outer casing 400. The reinforcing member 500 can be inserted into the insertion portion 424a of the outer casing 400. In particular, the reinforcing member 500 can be formed in a rod shape extending in one direction so as to be inserted into the insertion portion 424a. The insertion portions 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. Because the insertion portion 424a is provided in the outer casing 400 such that the outer surface of the insertion portion 424a is recessed inward, the reinforcing member 500 can be easily inserted into the insertion portion 424a by a simple operation of pushing the reinforcing member 500 inward from the outer surface of the outer casing 400, i.e., in the side direction.

[0075] The reinforcing member 500 may be made of a metal material. For example, the reinforcing member 500 may be a pair of steel pipes. As shown in FIG. 3, the reinforcing member 500 may be a rectangular parallelepiped steel pipe with a rectangular cross section. Furthermore, the reinforcing member 500 may be formed in the shape of a hollow pipe, as shown in the figure. In this case, further weight reduction can be achieved.

[0076] The reinforcing members 500 may be arranged so that a pair is inserted into the insertion portions 424a of the outer casing 400. This allows both sides of the outer casing 400 to be firmly supported. In this manner, even though the outer casing 400 is manufactured from a plastic injection molding, the reinforcing members 500 improve the mechanical properties of the outer casing 400, thereby ensuring structural stability. Compared to a case in which the cell assembly 100 is supported only by the base plate 420, the reinforcing members 500 allow the entire combined structure to support the load of the cell assembly 100, thereby ensuring structural safety.

[0077] FIG. 5 is a perspective view showing a base plate and a reinforcing member of a battery pack according to an embodiment of the present invention, and FIG. 6 is a partially enlarged view of FIG.

[0078] First, as shown in FIG. 5, the base plate 420 may have a lower vent hole 425 formed therein. And, as shown in FIGS. 1 and 2, the top cover 410 may have an upper vent hole 411 formed therein. The upper vent hole 411 and the lower vent hole 425 may be formed to have a vertically symmetrical structure. The upper vent hole 411, the air layer K1 shown in FIGS. 2 and 3, and the lower vent hole 425 may all be formed to be aligned vertically. Gas emitted from the battery cells 101 can be discharged to the outside of the battery pack 10 via the air layer K1 through the upper vent hole 411 and / or the lower vent hole 425. In this way, high-temperature and high-pressure gas generated in the battery cells 101 can be uniformly dispersed and discharged to the outside of the outer casing 400. This prevents the battery pack 10 from collapsing or warping when gas is emitted from the battery cells 101.

[0079] 5 and 6, the support frame portions 422 of the base plate 420 are provided on edge regions extending in the arrangement direction of the cell assemblies 100 and protrude upward at predetermined intervals along the arrangement direction of the cell assemblies 100. The base plate 420 may further include recesses 423 provided between adjacent support frame portions 422. Here, the arrangement direction of the cell assemblies 100 is the same as the stacking direction of the battery cells 101, and the edge regions extending in the arrangement direction of the cell assemblies 100 include edge regions in both directions of the X-axis in the base plate 420 of FIG.

[0080] Furthermore, the support frame portion 422 has an outer surface that is recessed inward, allowing the insertion portion 424a to be formed. The recessed shape is generally U-shaped, and this shape can fit with the reinforcing member 500. On the other hand, the recessed shape does not necessarily have to be U-shaped as long as it can fit with the reinforcing member 500. The recess 423 can be located between two adjacent support frame portions 422, as shown in FIG. 6.

[0081] Figure 7 is a diagram showing the bus bar frame in Figure 4 in more detail. Figures 8 and 9 are diagrams showing an assembly process or assembly structure of a base plate and multiple cell assemblies according to one embodiment of the present invention. Figure 10 is a diagram showing the assembled state of the base clip after inserting the reinforcing member in Figure 9.

[0082] 7 and 8, the recess 423 may be configured to fit with the mounting guide block 315 of the bus bar frame 310. In particular, the recess 423 may include a step on its upper surface, and the lower surface of the mounting guide block 315 may have a shape that matches the step. The step may provide a position guide and may particularly include a sloped portion to facilitate positioning and assembly of the guide block 315 into the recess 423. This allows the cell assembly 100 to be stably accommodated on the base plate 420.

[0083] Next, the assembly structure and fixing structure of the base plate 420 and the plurality of cell assemblies 100 will be described with reference to FIGS.

[0084] Each cell assembly 100 includes a bus bar frame assembly 300 with mounting guide blocks 315, and a base plate 420 with recesses 423 at regular intervals. The number of mounting guide blocks 315 provided in each cell assembly 100 is the same as the number of recesses 423 provided in the base plate 420.

[0085] Support frame portions 422 protrude from around the recesses 423. The mounting guide blocks 315 can fit into the recesses 423 while passing between adjacent support frame portions 422 from top to bottom, i.e., in the Z-axis direction. The recesses 423 can be formed in the edge regions of the base plate 420 so that, when the mounting guide blocks 315 of each cell assembly 100 are inserted into the corresponding recesses 423, the cell assemblies 100 are positioned at a fixed interval from one another on the base plate 420. Furthermore, as shown in FIGS. 3 and 7 , the bus bar frame 310 of each cell assembly 100 includes a mounting plate 314 that can be positioned to face the upper surface of the support frame portion 422.

[0086] Since the battery pack 10 according to one embodiment of the present invention includes the above-described configuration, when each cell assembly 100 is assembled to the base plate 420 so that the mounting guide block 315 and the recess 423 can fit together, the multiple cell assemblies 100 can each be easily positioned in a fixed position relative to the base plate 420, as shown in FIG. 8.

[0087] Furthermore, each cell assembly 100 is inserted so that the mounting guide block 315 can fit into the recess 423 between the two support frame portions 422, and therefore can be fixed in the Y-axis direction relative to the base plate 420 in Fig. 8. In other words, the mounting guide block 315 of the bus bar frame 310 is inserted into the recess 423 of the base plate 420, and the support frame portions 422 protrude around the recess 423 so as to be constrained on the left and right sides (Y-axis direction) of the recess 423, and therefore, after each cell assembly 100 is placed on the base plate 420, movement in the Y-axis direction is restricted.

[0088] 9, when the cell assembly 100 is mounted on the base plate 420 with each mounting guide block 315 inserted into a corresponding recess 423, the mounting guide blocks 315 and the support frame portions 422 can be configured to form a continuous assembly wall 424 along the arrangement direction of the cell assembly 100. In other words, the mounting guide blocks 315 and the support frame portions 422 can be arranged so that their predetermined internal spaces communicate with each other, and can also be arranged so that their predetermined internal spaces communicate with each other with other adjacent mounting guide blocks 315 and support frame portions 422, and a reinforcing member 500 can be inserted and arranged in such spaces.

[0089] The assembly wall 424 may have an outer surface recessed inward, thereby defining an insertion portion 424a of the outer casing 400. As shown in FIG. 9, a reinforcing member 500 may be inserted into the insertion portion 424a from the side.

[0090] The reinforcing member 500 may be manufactured in the form of a rod having a length corresponding to the length of the assembly wall 424. Such a reinforcing member 500 may be applied to both edge regions of the base plate 420 in substantially the same manner.

[0091] More specifically, the assembly wall 424 includes an upper storage wall 424_1, a lower storage wall 424_2, and a side storage wall 424_3, and the reinforcing member 500 is a rectangular parallelepiped steel pipe. An upper portion of the reinforcing member 500 may be in contact with the upper storage wall 424_1, a lower portion of the reinforcing member 500 may be in contact with the lower storage wall 424_2, and one side of the reinforcing member 500 may be in contact with the side storage wall 424_3.

[0092] The upper storage wall 424_1 formed by the support frame portion 422 of the base plate 420 and the upper storage wall 424_1 formed by the mounting guide block 315 of the bus bar frame 310 are aligned and have no step. The lower storage wall 424_2 formed by the support frame portion 422 and the lower storage wall 424_2 formed by the mounting guide block 315 are also aligned and have no step. The side storage wall 424_3 formed by the support frame portion 422 and the side storage wall 424_3 formed by the mounting guide block 315 are also aligned and have no step. Therefore, the internal space formed by the assembly wall 424 communicates with each other in the X-axis, Y-axis, and Z-axis directions to define an insertion portion 424a as an integrated space, thereby allowing the reinforcing member 500 to be stably inserted into the insertion portion 424a. Furthermore, after being inserted into the insertion portion 424a, the position of the reinforcing member 500 is constrained in the X-axis, Y-axis, and Z-axis directions.

[0093] 10, a base clip 510 may be attached to the base plate 420 to prevent the reinforcing member 500 from being removed from the insertion portion 424a. For example, after the reinforcing member 500 is inserted into the insertion portion 424a, the base clip 510 may be coupled to the support frame portion 422 of the base plate 420. The base clip 510 is used to fix the reinforcing member 500 to the base plate 420 and may be a bracket structure made of a steel material.

[0094] According to this embodiment, all of the cell assemblies 100 can be fixed to the base plate 420 in the X-axis, Y-axis, and Z-axis directions. That is, since each cell assembly 100 is fitted between the support frame portions 422 (at the edge regions on both sides) of the base plate 420, movement in the X-axis direction is also restricted. The support frame portions 422 and the mounting guide block 315 are fixed by the reinforcing member 500, so movement of the mounting guide block 315 in the Y-axis and Z-axis directions is restricted. Thereafter, the top cover 410 is further assembled to secondarily prevent loose movement of the reinforcing member 500, and the battery pack 10 can be completed.

[0095] Fig. 11 is a cross-sectional view of the battery pack in Fig. 1. The cross section is perpendicular to the Y-axis direction.

[0096] 11, the reinforcing member 500 is inserted inside the mounting guide block 315 of each cell assembly 100, so movement in the X-axis and Z-axis directions is restricted. As described above, the mounting guide block 315 of each cell assembly 100 is inserted into the recess 423, so movement in the Y-axis direction is restricted. In this way, the mounting guide block 315 and the support frame portion 422 also restrict the position of the reinforcing member 500 in the longitudinal direction and height direction of the reinforcing member 500.

[0097] Furthermore, since the reinforcing member 500 is inserted through the support frame portion 422 of the base plate 420 and the mounting guide block 315 of the bus bar frame 310 of the cell assembly 100, the reinforcing member 500 can fix the base plate 420 and the cell assembly 100. In other words, the reinforcing member 500 can fix the outer casing 400 and the bus bar frame assembly 300 to each other. In this way, it can be confirmed that the reinforcing member 500, the base plate 420, and the bus bar frame 310 can be used to restrain the X-axis and Z-axis directions without using bolts and nuts.

[0098] In this way, the base plate 420 and the bus bar frame 310 can be manufactured from a plastic structure by injection molding, and the two separate parts of the base plate 420 and the bus bar frame 310 are combined and fixed to each other by inserting and side-fixing the reinforcing member 500. The base plate 420 and the bus bar frame 310 can be joined together without the need for bolts and nuts, thereby enhancing structural safety.

[0099] From the perspective of process management, bolts and nuts require continuous checking and management of torque for fastening, the presence or absence of loosening during use of the fastened product, etc. There is also the problem of increased takt time due to the addition of processes for fastening and checking fastening. According to one aspect of the present invention, the use of bolts and nuts can be minimized, making process management easier and preventing an increase in takt time.

[0100] 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 having a snap fit 702 structure may be attached to the front plate 427 to prevent the terminal block 700 from coming off. The front cover 701 is detachably attached to the front plate 427.

[0101] Fig. 12 is a diagram showing a terminal block portion of a battery pack according to one embodiment of the present invention. Fig. 13 is a diagram for explaining the assembly and fixing structure of the terminal block in a battery pack according to one aspect of the present invention. Fig. 14 is a cross-sectional view taken along the line A-A' in Fig. 13, showing the state after the front cover has been assembled.

[0102] 12-14 in conjunction with FIG. 2, the base plate 420 and front plate 427 may be injection molded together.

[0103] The front plate 427 is a vertical plate provided on one side of the periphery of the base plate 420 and may serve as an electrical component mounting portion. For example, a terminal block 700 may be mounted on an outer surface of the front plate 427, and a battery management system (BMS) assembly 600 may also be mounted thereon. The BMS assembly 600 may be configured to measure the current and temperature of the battery cells 101 in the battery pack 10 and control the charging and discharging of the battery cells 101. The terminal block 700 may include electrode terminals of the battery pack 10, a fuse, and the like. A BMS mounting portion 600A and a terminal block mounting portion 700A may be provided on the outer surface of the front plate 427 to mount the BMS assembly 600 and the terminal block 700. In particular, the terminal block mounting portion 700A may be configured to include a stepped portion 428.

[0104] 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 removably mounted on the front plate 427 through the opening 412 in the top cover 410.

[0105] 12, terminal block 700 can be mounted to a stepped portion 428 of front plate 427. Conventionally, when assembling a terminal block, rotation is prevented by torque, and bolts are used to secure the terminal block in place and prevent rotation. In one aspect of the present invention, a structural step can be used to prevent rotation of terminal block 700, and a snap fit 702 structure can be used to secure front cover 701 of terminal block 700 to front plate 427.

[0106] The wall formed by the step at step portion 428 serves as a position guide during assembly and prevents rotation after assembly. The snap fit 702 structure prevents the terminal block 700 from coming off after assembly.

[0107] Conventionally, when assembling a terminal block, rotation due to torque is prevented by tightening bolts to fix the terminal block in place and to prevent rotation. However, with this embodiment of the present invention, the use of step portion 428 minimizes the use of bolts and nuts.

[0108] Meanwhile, the BMS assembly 600 may be mounted to the front plate 427 via an insert nut 610. The front plate 427 may be provided taking into consideration the time of plastic injection so that the BMS assembly 600 can be mounted to the BMS mounting portion 600A via the insert nut 610 without the need for a separate BMS housing.

[0109] In this way, the front plate 427 can be manufactured by integrally molding the BMS mounting portion 600A and the terminal block mounting portion 700A. Plastic injection molding provides satisfactory insulation, weight reduction, and cost savings. Furthermore, bolt and nut fastening is not required to secure the terminal block 700 in place.

[0110] From the perspective of process management, bolts and nuts require continuous checking and management of torque for fastening, whether or not there is any loosening due to use of the product after fastening, etc. There is also a problem of increased takt time due to the addition of processes for fastening and checking fastening. One aspect of the present invention proposes a structure that minimizes the fastening structure using bolts and nuts in the battery pack 10 and structurally assembles and fastens internal components.

[0111] According to one aspect of the present invention, it is possible to minimize design and management factors for the battery pack 10 and prevent problems that may occur. That is, it is possible to provide a battery pack 10 that requires fewer design variables to be considered for fastening the internal pack components than when using bolts and nuts, is easier to manage from a process management perspective than when using bolts and nuts, and does not increase takt time. According to one aspect of the present invention, material costs are reduced by simplifying the structure and reducing the number of parts. According to one aspect of the present invention, productivity is improved by shortening the takt time.

[0112] FIG. 15 is a schematic diagram of an energy storage system according to one embodiment of the present invention.

[0113] The energy storage system 20 may include one or more battery packs 10 according to an embodiment of the present invention described above. In particular, the energy storage system 20 may include a plurality of battery packs 10 according to an embodiment of the present invention electrically connected to each other due to its large energy capacity. In addition, the energy storage system 20 according to an embodiment of the present invention may further include various other components of energy storage systems known at the time of filing of this application. Furthermore, such an energy storage system 20 may be used in various locations and devices, such as smart grid systems and electric charging stations.

[0114] For example, the energy storage system 20 may include a plurality of battery racks including the battery packs 10 according to an embodiment of the present invention. The battery packs 10 may be configured to be arranged vertically and housed in a rack case (not shown). The plurality of battery packs 10 may be mounted vertically spaced apart inside the rack case. The rack case may have an accommodation space with an open structure that allows the plurality of battery packs 10 to communicate with each other vertically. The battery rack may include a rack BMS (Battery Management System) on 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 installed in the battery rack. The plurality of battery racks may be electrically connected to each other via a rack bus bar (not shown).

[0115] The energy storage system 20 according to an embodiment of the present invention includes the battery pack 10 according to an embodiment of the present invention, thereby making it possible to utilize the advantages of the battery pack 10 as they are. Since the electrical insulation and structural safety of the battery pack 10 are ensured, the energy storage system 20 including the battery pack 10 has excellent safety. Since the structural safety of the battery pack 10 is ensured and the battery pack 10 is lightweight, the battery pack 10 can be easily transported and installed. 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 the battery pack 10 can be reduced.

[0116] In this specification, directional terms such as up, down, left, right, front, and rear are used, but these terms are used merely for ease of explanation, and it will be obvious to those skilled in the art of the present invention that they may differ depending on the position of the object in question, the position of the observer, etc.

[0117] Although the present invention has been described above using limited embodiments and drawings, it should be understood that the present invention is not limited thereby and that those skilled in the art can implement the present invention by making various modifications and variations within the scope of the technical idea of ​​the present invention and the equivalent scope of the appended claims. [Explanation of symbols]

[0118] 10 Battery Pack 20 Energy storage device 100 Cell Assembly 101 battery cells 102 Electrode Lead 110, 120 cell stack K1 Air Layer 300 Busbar frame assembly 310 Busbar Frame 314 Stationary Plate 315 Guide Block 320 Busbar 400 Outer casing 410 Top cover 412 Aperture 420 base plate 422 Support frame part 423 Recess 424 Assembly wall 424a Insertion part 427 Front Plate 428 Step 500 Reinforcement member 510 Base Clip 700 terminal block 701 Front cover 702 Snap Fit

Claims

1. at least one cell assembly including a plurality of battery cells; an outer casing for accommodating the cell assembly, the outer casing having an insertion portion formed in an outer surface thereof along a longitudinal direction and having an inwardly recessed shape; a rod-shaped reinforcing member inserted into the insertion portion; Including the battery pack.

2. The outer casing is a base plate on which the battery cell is mounted; a support frame portion provided on each side of the base plate and constituting the insertion portion; 10. The battery pack of claim 1, comprising:

3. The battery pack according to claim 2 , wherein the base plate and the support frame portion are integrally injection molded.

4. The battery pack according to claim 1 , wherein the reinforcing member is a pair of steel pipes.

5. The outer casing is made of a plastic material, The battery pack according to claim 1 , wherein the reinforcing member is made of a metal material.

6. The battery pack according to claim 1 , further comprising a base clip for fixing the position of the reinforcing member.

7. the at least one cell assembly is a plurality of cell assemblies arranged side by side; the cell assembly includes a bus bar frame assembly; The support frame portion of the base plate is 4. The battery pack according to claim 2 or 3, wherein the bus bar frame assemblies are provided in edge regions extending in an arrangement direction of the cell assemblies, and protrude upward at predetermined intervals along the arrangement direction of the cell assemblies to support the bus bar frame assemblies of each of the cell assemblies.

8. the base plate further includes recesses provided between adjacent support frame portions; the bus bar frame assembly of each of the cell assemblies includes a bus bar frame of electrically insulating material; The bus bar frame is a mounting plate disposed on an upper surface of the support frame; a mounting guide block protruding downward from the mounting plate so as to be insertable into the corresponding recess; 8. The battery pack of claim 7, comprising:

9. The battery pack according to claim 8 , wherein the mounting plate and the mounting guide block are integrally formed on the bus bar frame by injection molding.

10. The battery pack according to claim 8 , wherein the recess includes a step on an upper surface thereof, and the lower surface of the mounting guide block has a shape that matches the step.

11. 9. The battery pack of claim 8, wherein when the cell assemblies are placed on the base plate with the respective mounting guide blocks inserted into the corresponding recesses, the respective mounting guide blocks and the support frame portion are configured to form a continuous assembly wall along the arrangement direction of the cell assemblies, and the assembly wall defines the insertion portion.

12. 12. The battery pack according to claim 11, wherein the mounting guide block and the support frame portion constrain the position of the reinforcing member in the longitudinal direction and the height direction of the reinforcing member, and the outer casing and the bus bar frame assembly are fixed to each other by the reinforcing member.

13. the assembly wall includes an upper storage wall, a lower storage wall, and a side storage wall; The reinforcing member is a rectangular parallelepiped steel pipe, 12. The battery pack of claim 11, wherein an upper portion of the steel pipe contacts the upper housing wall, a lower portion of the steel pipe contacts the lower housing wall, and one side of the steel pipe contacts the side housing wall.

14. 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; 4. The battery pack according to claim 2, wherein a front cover having a snap-fit ​​structure for preventing the terminal block from coming off is attached to the front plate.

15. The battery pack of claim 14 , wherein the base plate and the front plate are integrally injection molded.

16. the front plate is a vertical plate provided on one side of the periphery of the base plate, The terminal block is attached to the outer surface of the front plate, The battery pack further includes a top cover with an opening; The battery pack according to claim 14 , wherein the terminal block is exposed or shielded by the front cover that is detachably provided on the front plate through the opening in the top cover.

17. An energy storage system comprising at least one battery pack according to any one of claims 1 to 3.

Images