Battery pack and energy storage system including the 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 specifically, 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 based on Korean Patent Application No. 10-2022-0138105 filed on October 25, 2022, and all contents disclosed in the specification and drawings of that application are incorporated into this application.

Background Art

[0002] Secondary batteries, which have high applicability to product groups and electrical characteristics such as high energy density, are widely applied not only to portable devices, but also to electric vehicles (EVs) driven by electric drive sources, hybrid electric vehicles (HEVs), and the like. Such secondary batteries not only have the unique advantage of being able to dramatically reduce the use of fossil fuels, but also have the advantage of generating no by-products accompanying energy use. Therefore, they are attracting attention as a new energy source for improving environmental friendliness and energy efficiency.

[0003] Types of secondary batteries that are currently widely used include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and the like. The operating voltage of such a unit secondary battery cell, that is, a unit battery cell, is approximately 2.5V to 4.5V. Therefore, when a higher output voltage is required, a plurality of battery cells may be connected in series to form a battery pack. In addition, depending on the charge and discharge capacity required for the battery pack, a plurality of battery cells may be connected in parallel to form a battery pack. Therefore, the number of battery cells included in the battery pack can be variously set according to the required output voltage and / or charge and discharge capacity.

[0004] Energy storage systems (ESS), which have recently attracted attention, are devices that maximize the efficiency of electricity use by storing the electricity produced in battery packs and supplying it to consumers when needed. An ESS consists of multiple battery packs forming a single battery rack, with dozens or even hundreds of battery racks coming together to form a single system. They are sometimes used in conjunction with uninterruptible power supplies (UPS) to ensure a stable power supply in response to sudden power interruptions or anomalies, and with solar power generation systems that convert sunlight into electrical energy. Furthermore, with the full-scale commercialization of electric vehicles, such ESSs can also be adopted in EV charging stations and EV charging spots where electric vehicles can be charged.

[0005] In the case of battery packs used in energy storage systems (ESS), they can be formed in a shape 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 made of a highly rigid metal material, usually steel, to support the high load of multiple battery cells.

[0006] However, in this case, electrical insulation between the casing and the electrical components, particularly between the casing and the battery cells, becomes a concern. To resolve this, additional insulating structures or separate insulating components must be used between the casing and the battery cells. This leads to problems such as increased manufacturing time, increased cycle time, and higher manufacturing costs for the battery pack.

[0007] On the other hand, conventional energy storage systems (ESS) battery packs have a structure that uses bolt-nut connections to fix the internal pack components. In addition, torque is used to prevent rotation during the assembly of the terminal block, and bolts are used to fix the position of the terminal block and prevent rotation.

[0008] As with conventional bolt-nut systems, structural considerations are necessary to achieve this, such as avoiding inserts and undercuts. Furthermore, the design must also take into account potential insulation weakening. From a process control perspective, bolt-nut systems require torque control for fastening, and continuous monitoring and control are necessary to ensure proper fastening and prevent loosening during product use. This also presents the problem of increased cycle time due to the addition of fastening and verification processes.

[0009] Therefore, there is a need to develop technologies for outer casing structures that ensure electrical insulation between the outer casing and electrical components, while also improving structural rigidity and safety to firmly support multiple battery cells. Furthermore, there is a need to develop technologies for battery packs that require even fewer design variables to be considered for fixing internal pack components than when using bolts and nuts. [Overview of the initiative] [Problems that the invention aims to solve]

[0010] The present invention was created to solve the aforementioned problems against the background described above, and the problem that the present invention aims to solve is to provide a battery pack and an energy storage system including the same that ensures electrical insulation and structural safety.

[0011] Another problem that the present invention aims to solve is to provide a battery pack and an energy storage system including the same that requires even fewer design variables to be considered for fixing the internal pack components than when using bolts and nuts, is easier to manage from a process control standpoint than when using bolts and nuts, and does not increase the cycle time. [Means for solving the problem]

[0012] The battery pack of the present invention, which solves the above-mentioned problems, includes at least one cell assembly containing a plurality of battery cells, an outer casing for housing the cell assembly, the outer casing having an insertion portion along its longitudinal direction which is provided in a shape that is recessed inward on its outer surface, 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 can be integrally injection molded.

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

[0016] The outer casing may be manufactured from a plastic material, and the reinforcing member may be manufactured from 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 is a plurality of cell assemblies arranged side by side, and the cell assembly may include a busbar frame assembly.

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

[0020] The base plate further includes recesses 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, the busbar frame may include a mounting plate positioned on the upper surface of the support frame portion and mounting guide blocks projecting downward from the mounting plate so as to be insertable into the corresponding recesses.

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

[0022] The recess may include a step on its upper surface, and the lower surface of the aforementioned mounting guide block may have a shape corresponding to the step.

[0023] When the cell assembly is placed on the base plate with each of the aforementioned 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 assembly, and the assembly wall can limit the insertion portion.

[0024] The mounting guide block and the support frame portion restrain the position of the reinforcing member in the longitudinal and height directions, and the reinforcing member can fix the outer casing and the busbar frame assembly to each other.

[0025] The assembled wall body includes an upper housing wall, a lower housing wall, and a side housing wall, and the reinforcing member is a rectangular parallelepiped steel pipe, the upper part of the steel pipe is in contact with the upper housing wall, the lower part of the steel pipe is in contact with the lower housing wall, and one side of the steel pipe may be in contact with the side housing wall.

[0026] 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 front cover having a snap-fit structure for preventing the terminal block from detaching can be mounted on the front plate.

[0027] The base plate and the front plate may be integrally formed by injection molding.

[0028] The front plate is in the shape of a vertical plate provided on a peripheral edge portion at one side of the base plate, the terminal block is mounted on an outer surface of the front plate, the battery pack further includes a top cover with an opening, and the terminal block can be exposed or shielded by using the front cover that is detachably provided on the front plate via the opening of the top cover.

[0029] Further, one aspect of the present invention provides an energy storage system, characterized by comprising at least one battery pack according to one aspect of the present invention. Effects of the Invention

[0030] According to one aspect of the present invention, manufacturing the outer casing from a plastic injection molded product makes it possible to ensure insulation between the outer casing and the battery cells, and inserting a reinforcing member into the outer casing improves the mechanical properties of the outer casing, making it possible to ensure structural stability.

[0031] In particular, according to one aspect of the present invention, it is possible to provide a battery pack configured such that perfect insulation can be achieved by applying an injection-molded outer casing without a separate insulating component. As a result, electrical insulation between the outer casing and the battery cells can be achieved without an additional insulating structure or a separate insulating component, which makes it possible to reduce the number of manufacturing steps, tact time and manufacturing cost of the battery pack.

[0032] Furthermore, according to one aspect of the present invention, the outer casing and the busbar frame assembly are fixed to each other by reinforcing members, providing a robust fastening structure that improves resistance to warping, bending, or loosening.

[0033] Furthermore, by using a fixing configuration with reinforcing members, the fixing structure using bolts and nuts can be minimized. In particular, one aspect of the present invention proposes a structure in which the fixing structure using bolts and nuts in a battery pack is minimized, and the internal components are structurally assembled and fixed. According to one aspect of the present invention, the design and control factors of the battery pack can be minimized, and the occurrence of problems that may occur can be suppressed. That is, there are even fewer design variables to consider in fixing the internal pack components than when bolts and nuts are used, it is easier to manage from a process control standpoint than when bolts and nuts are used, and a battery pack can be provided that does not increase the cycle 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 cycle time. According to one aspect of the present invention, the battery pack can be made lighter by simplifying the process and structure. According to one aspect of the present invention, since the outer casing is made of plastic injection rather than steel, it is not only lightweight, but also lighter than existing bolt-nut structures because it eliminates the weight of bolts and nuts, and the resin required to realize the injection structure for fixing.

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

[0036] Furthermore, by incorporating such battery packs, energy storage systems become safer, easier to transport and install, and reduce production costs.

[0037] The drawings accompanying this specification illustrate preferred embodiments of the present invention and are intended to further illustrate the technical idea of ​​the invention along with the content of the invention; therefore, the present invention shall not be construed as being limited only to what is shown in the drawings. [Brief explanation of the drawing]

[0038] [Figure 1] This is a perspective view of a battery pack according to one embodiment of the present invention. [Figure 2] This image shows the battery pack with the top cover removed, as shown in Figure 1. [Figure 3] Figure 1 is a partially exploded perspective view showing the main parts of the battery pack. [Figure 4] This is a perspective view showing a battery pack cell assembly according to one embodiment of the present invention. [Figure 5] This is a perspective view showing a base plate and reinforcing member of a battery pack according to one embodiment of the present invention. [Figure 6] This is a magnified section of Figure 5. [Figure 7] This figure shows the busbar frame in more detail. [Figure 8] This figure shows 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] This figure shows 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] Figure 9 shows the base clip assembled after the reinforcing member has been inserted. [Figure 11] Figure 1 is a cross-sectional view of the battery pack. [Figure 12]This figure shows the terminal block portion of a battery pack according to one embodiment of the present invention. [Figure 13] This figure illustrates the assembly and fixing structure of a terminal block in a battery pack according to one aspect of the present invention. [Figure 14] This corresponds to the cross-section viewed along the line A-A' in Figure 13, and shows the front cover after it has been assembled. [Figure 15] This is a schematic diagram of an energy storage system according to one aspect of the present invention. [Modes for carrying out the invention]

[0039] Preferred embodiments of the present invention will now be described in detail based on the accompanying drawings. Prior to this, terms and words used in this specification and in the claims are not to be interpreted in their ordinary or dictionary sense, but rather in accordance with the principle that the inventor may appropriately define the concepts of terms in order to best describe the invention, and are to be interpreted in the sense and concepts corresponding to the technical idea of ​​the present invention. Therefore, the embodiments described herein and the configurations shown in the drawings are merely preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention; it should be understood that there may be a variety of equivalent and modified embodiments that can be substituted for these at the time of this application.

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

[0041] Referring to Figures 1 to 3, a battery pack 10 according to one aspect of the present invention may be a three-dimensional structure having predetermined lengths, widths, and heights in the X, Y, and Z axes, respectively. The battery pack 10 includes a cell assembly (CMA) 100, an outer casing 400, and reinforcing members 500. The battery pack 10 may further include a base clip for fixing the position of the reinforcing members 500 and a top cover 410.

[0042] A battery pack 10 according to one aspect of the present invention includes one or more cell assemblies 100, where a cell assembly 100 refers to a group of battery cells 101.

[0043] The battery pack 10 may be configured to include multiple cell assemblies 100. For example, as shown in the embodiment of Figure 2, the battery pack 10 may include four cell assemblies 100 arranged side by side. The battery pack 10 then includes an outer casing 400 to protect the four cell assemblies 100 from the outside.

[0044] The outer casing 400 is the part that houses the cell assembly 100. When the top cover 410 is attached to the outer casing 400 as shown in Figure 1, an empty space is formed inside in which the cell assembly 100 can be housed, and the cell assembly 100 can be housed in such an empty space.

[0045] The outer casing 400 can support the cell assembly 100. In particular, the outer casing 400 can primarily support the lower surface of the cell assembly 100. Such an outer casing 400 can be mounted on machinery or mechanisms that use the battery pack 10 as an energy source. For example, the outer casing 400 can be mounted on energy storage systems or electric vehicles.

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

[0047] 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 may be provided in the shape of a generally plate-like body with an area capable of supporting multiple cell assemblies 100.

[0048] In particular, the base plate 420 and the top cover 410 may each include two unit parts arranged to extend in one direction (in this embodiment, the Y-axis direction), with each unit part connected to the others. Figure 3 shows the left-hand unit part of the two unit parts. On one side of the unit parts facing each other, fastening projections protruding in opposite directions and fastening receiving grooves coupled to these fastening projections are provided, allowing the unit parts to be assembled without any steps at the connection points. When increasing the size of the outer casing 400 to manufacture a large-capacity battery pack, manufacturing it as a single unit may lead to manufacturing difficulties and inconveniences in 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 to an appropriate size and assembled in a simple manner, which has the advantage of being convenient in the manufacturing and handling process. Furthermore, the base plate 420 has the effect of further improving structural rigidity at the connection points of each unit part, and further improving resistance to warping, bending, or sagging in the thickness direction (Z-axis direction).

[0049] Next, the detailed configuration of the cell assembly 100 will be described based on Figure 4.

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

[0051] Referring further to Figure 4, the cell assembly 100 may include a plurality of battery cells 101. A predetermined number of battery cells 101 may come together to form a single cell assembly 100.

[0052] Each cell assembly 100 may include cell stacks 110, 120, each containing a plurality of battery cells 101. Preferably, the cell stacks 110, 120 are separated from each other by an air layer K1 at a predetermined distance.

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

[0054] The air layer K1 can serve to block heat transfer between the cell stacks 110 and 120. For example, if 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 cell stack 120 to the other cell stack 110. Therefore, when a thermal event occurs in a specific battery cell 101, it is possible to prevent the heat from propagating in a chain reaction to all battery cells 101 included in the cell assembly 100. The air layer K1 can also be used as a gas transport passage when gas is generated in the battery cell 101.

[0055] The battery cells 101 may consist of pouch-type rechargeable batteries and may be arranged in multiples and electrically connected to one another. For electrical connection, the cell assembly 100 includes a busbar frame assembly 300.

[0056] Each battery cell 101 may include an electrode assembly, a battery case housing the electrode assembly, and electrode leads 102 protruding outside the battery case and electrically connected to the electrode assembly. The electrode leads 102 may include a positive lead and a negative lead, the positive lead being connected to the positive electrode plate of the electrode assembly, and the negative lead being connected to the negative electrode plate of the electrode assembly.

[0057] In the illustrated example, each battery cell 101 includes a pair of electrode leads 102 that protrude from both sides in its longitudinal direction (X-axis direction). In other words, the electrode leads 102 may be provided on 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 and 120 are assemblies of multiple battery cells 101 stacked in one direction (Y-axis direction). The battery cells 101 can be arranged so that they are aligned horizontally (Y-axis direction) while standing upright in the vertical direction (Z-axis direction). That is, the battery cells 101 can be arranged in a shape where their wide surfaces are standing vertically to the ground and stacked horizontally.

[0059] The busbar frame assembly 300 is positioned in front of and behind the cell stacks 110 and 120, which are arranged side by side at a predetermined distance apart in the left-right direction (Y-axis direction). In other words, the busbar frame assembly 300 is positioned in front of and behind the cell stacks 110 and 120 in a direction that intersects with the stacking direction of the battery cells 101.

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

[0061] The busbar frame assembly 300 includes a busbar frame 310 and a number of busbars 320.

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

[0063] Multiple busbars 320 can be manufactured in the form of rods or plates from electrically conductive metal materials such as copper, aluminum, or nickel. Such multiple busbars 320 can be mounted on a busbar frame 310 at regular intervals from one another along the stacking direction of the battery cells 101.

[0064] The battery cells 101 constituting the cell stacks 110 and 120 can have their electrode leads 102 drawn out to the outside of the busbar frame 310 by passing through the corresponding lead slits. The electrode leads 102 drawn out to the outside of the busbar frame 310 can be bent and mounted to be fixed to the surface of the corresponding busbar 320. For example, the busbar 320 and the electrode leads 102 can be fixedly joined to each other by laser welding or ultrasonic welding. For example, the positive electrode leads of two battery cells 101 can be overlapped and mounted to a particular busbar 320, and the negative electrode leads of two other battery cells 101 can be overlapped and mounted to the same particular busbar 320. Then the four battery cells 101 can be connected to each other in series and / or in parallel. In this manner, by attaching the electrode leads 102 of the battery cells 101 to the corresponding busbars 320, all battery cells 101 contained in the cell stacks 110 and 120 can be connected in series and / or in parallel.

[0065] The busbar frame 310 can achieve electrical insulation. Since the busbar frame 310 can be manufactured from plastic structures by injection molding, separate insulation treatments or insulating components are unnecessary. It also contributes to weight reduction.

[0066] Furthermore, it is preferable that the components be made of injection-molded structures for realizing mating parts with the base plate 420. In the battery pack 10 according to this embodiment, the busbar frame 310 of the busbar frame assembly 300 may further include a mounting plate 314 placed on the upper surface of the support frame portion 422 of the base plate 420, and a mounting guide block 315 protruding downward from such mounting plate 314. The mounting plate 314 and the mounting guide block 315 are components for improving the assembly and fixing of the multiple cell assemblies 100 and the base plate 420. The mounting plate 314 and the mounting guide block 315 can be integrally injection-molded with the busbar frame 310. The mounting plate 314 and the mounting guide block 315 will be described in more detail below in relation to the base plate 420.

[0067] Returning to Figures 1 to 3, the outer casing 400 can be formed from a plastic material. The outer casing 400 as a whole can be manufactured from a plastic material. In particular, the outer casing 400 can be formed in the shape of a plastic injection mold. By manufacturing the outer casing 400 from a plastic injection mold in this way, it becomes possible to ensure insulation from the battery cell 101.

[0068] Multiple cell assemblies 100 can be placed on 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 arranged along the Y-axis, and busbar frame assemblies 300, which connect the electrode leads 102 in the cell assemblies 100, are placed on both sides of the base plate 420. If a cell assembly includes one in which the electrode leads protrude in one direction along the X-axis, the busbar frame assemblies may be placed on one side of the base plate.

[0069] In particular, the base plate 420 can achieve electrical insulation and is preferably composed of an injection-molded structure for realizing a mating part with the cell assembly 100. The base plate 420 can be manufactured from a plastic structure by injection molding, eliminating the need for separate insulation treatment or insulating parts for electrical insulation. Furthermore, it is possible to achieve even greater weight reduction compared to when the outer casing is formed from a metal material.

[0070] Conventionally, the base plate of the battery pack's outer casing was manufactured by extrusion or from a rigid material such as steel plate. This presented a problem: the need to employ additional insulating components for insulation led to increased weight and higher costs. A battery pack 10 according to one aspect of the present invention employs an injection-molded outer casing, thus eliminating the need for additional insulating components. Consequently, weight and cost can be reduced.

[0071] However, when using plastic injection molding, the structural safety of the outer casing 400 may be questioned. Furthermore, as the size of the outer casing 400 increases, the plastic injection molding outer casing 400 structure may experience more warping, bending, and sagging compared to conventional outer casings made of steel, potentially weakening it in terms of strength and rigidity, thus limiting its ability to provide robust support.

[0072] Therefore, in this embodiment, a reinforcing member 500 is provided on the outer casing 400. That is, the structural rigidity of the injection-molded 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 an even smaller volume and weight compared to the steel base plate of the outer casing of a conventional battery pack. Accordingly, the battery pack 10 according to one aspect of the present invention can reduce weight and cost compared to a conventional battery pack.

[0073] The outer casing 400 is provided with an insertion portion 424a along its longitudinal direction, which is provided in a shape that is recessed inward on its outer surface. 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 so as to be able to form such an insertion portion 424a. The base plate 420 and the support frame portion 422 can be injection molded integrally. By manufacturing the outer casing 400 from a plastic injection mold in this way, it is possible to ensure insulation from the battery cell 101, as well as ensure ease of processing and reduce manufacturing man-hours. In this way, since electrical insulation can be achieved without further insulating structures or separate insulating parts by manufacturing the outer casing 400 from a plastic injection mold, it is possible to shorten the cycle time of the battery pack 10 and reduce 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 into a rod shape that extends elongated in one direction in order to be inserted into the insertion portion 424a. The insertion portion 424a can be provided on both sides of the outer casing 400. Therefore, the reinforcing member 500 can be inserted from the side of the battery pack 10. Since the insertion portion 424a is provided in the outer casing 400 with an outer surface that is recessed inward, the reinforcing member 500 can be easily inserted into the insertion portion 424a by a simple operation of pushing it inward from the outer surface of the outer casing 400, that is, in the side direction.

[0075] The reinforcing member 500 can be manufactured from a metal material. For example, the reinforcing member 500 may be a pair of steel pipes. Alternatively, as shown in Figure 3, the reinforcing member 500 may be a rectangular steel pipe with a rectangular cross-section. Furthermore, the reinforcing member 500 may be provided in the shape of a hollow pipe, as shown in the figure. In this case, further weight reduction can be achieved.

[0076] Such reinforcing members 500 can be arranged so that a pair is inserted into the insertion portion 424a of the outer casing 400. Through this, both sides of the outer casing 400 can be firmly supported. In this way, even though the outer casing 400 is manufactured from plastic injection molding, the reinforcing members 500 improve the mechanical properties of the outer casing 400 and ensure structural stability. Compared to the case where the cell assembly 100 is supported only by the base plate 420, the reinforcing members 500 enable the entire connecting structure to support the load of the cell assembly 100, thereby ensuring structural safety.

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

[0078] First, as shown in Figure 5, the base plate 420 may be provided with a perforated lower vent hole 425. Then, as shown in Figures 1 and 2, the top cover 410 may be provided with a perforated upper vent hole 411. The upper vent hole 411 and the lower vent hole 425 may be formed to have a vertically symmetrical structure. Furthermore, the upper vent hole 411, the air layer K1 shown in Figures 2 and 3, and the lower vent hole 425 may all be formed to be matched in the vertical direction. Gas ejected from the battery cell 101 can be discharged to the outside of the battery pack 10 through the air layer K1 and the upper vent hole 411 and / or the lower vent hole 425. In this way, the high-temperature, high-pressure gas generated in the battery cell 101 can be uniformly dispersed and discharged to the outside of the outer casing 400. This makes it possible to prevent collapse or distortion of the battery pack 10 when gas is ejected from the battery cell 101.

[0079] On the other hand, as shown in Figures 5 and 6, the support frame portion 422 of the base plate 420 is provided on the edge region 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. The base plate 420 may further include recesses 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 cells 101, and the edge region extending in the arrangement direction of the cell assembly 100 includes the edge regions in both directions along the X axis in the base plate 420 of Figure 5.

[0080] Furthermore, the support frame portion 422 has a shape in which its outer surface is recessed inward, so that it is possible to form an insertion portion 424a. The recessed shape is generally provided in the shape of a "U", and such a shape can be fitted with the reinforcing member 500. On the other hand, the recessed shape does not necessarily have to be a "U" shape, as long as it can be fitted with the reinforcing member 500. The recess 423 may be located between two adjacent support frame portions 422, as shown in Figure 6.

[0081] Figure 7 is a diagram showing the busbar frame of Figure 4 in more detail. Figures 8 and 9 are diagrams showing the 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 is a diagram showing the state in Figure 9 after the reinforcing member has been inserted and the base clip has been assembled.

[0082] The recess 423 may be configured to fit with the mounting guide block 315 of the busbar frame 310, as shown in Figures 7 and 8. 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 corresponding to the step. The step can provide position guidance and may be configured to include an inclined portion in particular to facilitate the positioning and assembly of the guide block 315 into the recess 423. This allows the cell assembly 100 to be stably placed and housed on the base plate 420.

[0083] Next, the assembly structure and fixing structure of the base plate 420 and the multiple cell assemblies 100 will be described based on Figures 8 to 10.

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

[0085] Support frame portions 422 are provided protruding around the recess 423. The mounting guide block 315 can fit into the recess 423 by passing from top to bottom, i.e., in the Z-axis direction, between adjacent support frame portions 422. The recess 423 can be formed in the edge region of the base plate 420 such that when the mounting guide block 315 of each cell assembly 100 is inserted into the corresponding recess 423, the cell assemblies 100 are arranged on the base plate 420 at a certain distance from each other. In addition, the busbar frame 310 of each cell assembly 100 includes a mounting plate 314 that can be positioned facing the upper surface of the support frame portion 422, as also shown in Figures 3 and 7.

[0086] Since the battery pack 10 according to one aspect of the present invention includes the above configuration, when each cell assembly 100 is assembled on the base plate 420 so that the mounting guide block 315 and the recess 423 can be fitted together, multiple cell assemblies 100 can be easily positioned on the base plate 420, as shown in Figure 8.

[0087] Furthermore, each cell assembly 100 is inserted such that the mounting guide block 315 fits into the recess 423 between the two support frame portions 422, so that, as shown in Figure 8, it can be fixed to the base plate 420 in the Y-axis direction. In other words, since the mounting guide block 315 of the busbar frame 310 is inserted into the recess 423 of the base plate 420, and the support frame portions 422 are provided protruding around the recess 423 so as to be constrained to the left and right sides (Y-axis direction) of the recess 423, the movement of each cell assembly 100 in the Y-axis direction is restricted after it is placed on the base plate 420.

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

[0089] Since the assembled wall 424 can be provided with an outer surface that is recessed inward, the insertion portion 424a of the outer casing 400 is limited. As shown in Figure 9, a reinforcing member 500 can be inserted into the insertion portion 424a from the side.

[0090] The reinforcing member 500 can be manufactured in the shape of a rod having a length corresponding to the length of the assembled wall 424. Such a reinforcing member 500 can be applied substantially similarly to the edge regions on both sides of the base plate 420.

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

[0092] The upper housing wall 424_1 formed by the support frame portion 422 of the base plate 420 and the upper housing wall 424_1 formed by the mounting guide block 315 of the busbar frame 310 are aligned and there is no step. The lower housing wall 424_2 formed by the support frame portion 422 and the lower housing wall 424_2 formed by the mounting guide block 315 are also aligned and there is no step. The side housing wall 424_3 formed by the support frame portion 422 and the side housing wall 424_3 formed by the mounting guide block 315 are also aligned and there is no step. Therefore, the internal space of the assembled wall body 424 communicates with each other in the X, Y, and Z axis directions, defining the insertion portion 424a of the integrated space, thereby enabling 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, Y, and Z axis directions.

[0093] On the other hand, to prevent the reinforcing member 500 from being easily dislodged from the insertion portion 424a, a base clip 510 can be attached to the base plate 420, as shown in Figure 10. For example, after the reinforcing member 500 is inserted into the insertion portion 424a, the base clip 510 can be connected to the support frame portion 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 material.

[0094] With this configuration, 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 fitted between the support frame portions 422 (on both side edges) of the base plate 420, so its 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, thereby restricting the movement of the mounting guide block 315 in the Y-axis and Z-axis directions. After this, the top cover 410 can be assembled to secondarily prevent the reinforcing member 500 from moving, and the battery pack 10 can be completed.

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

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

[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 busbar 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 outer casing 400 and the busbar frame assembly 300 can be fixed to each other by the reinforcing member 500. Thus, it can be confirmed that the reinforcing member 500, the base plate 420 and the busbar frame 310 can be restrained in the X-axis and Z-axis directions without the use of bolts and nuts.

[0098] Thus, the base plate 420 and the busbar frame 310 can be manufactured from a plastic structure by injection molding, and the base plate 420 and the busbar frame 310, which are divided into two parts, are combined and fixed to each other by insertion of reinforcing members 500 and side fixing. The base plate 420 and the busbar frame 310 can be joined without bolts and nuts, and structural safety can be enhanced.

[0099] From a process control perspective, bolts and nuts require continuous verification and control of torque for fastening, the presence or absence of loosening due to product use after fastening. There is also the problem that the cycle time increases due to the addition of processes for fastening and verification. According to one aspect of the present invention, the use of bolts and nuts can be minimized, making it easier to manage from a process control perspective and preventing an increase in cycle time.

[0100] On the other hand, referring to Figures 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, and a front cover 701 with a snap-fit ​​702 structure that prevents the terminal block 700 from detaching may be attached to the front plate 427. The front cover 701 is detachably provided on the front plate 427.

[0101] Figure 12 shows the terminal block portion of a battery pack according to one embodiment of the present invention. Figure 13 is a diagram illustrating the assembly and fixing structure of the terminal block in a battery pack according to one aspect of the present invention. Figure 14 corresponds to the cross section taken along the line A-A' in Figure 13, and shows the battery pack after the front cover has been assembled.

[0102] Referring to Figures 12-14 in conjunction with Figure 2, the base plate 420 and the front plate 427 can be injection molded as a single unit.

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

[0104] The top cover 410 may include an opening 412. The terminal block 700 can be exposed or shielded using a front cover 701 which is detachably provided on the front plate 427 through the opening 412 of the top cover 410.

[0105] Referring to Figure 12, the terminal block 700 can be mounted on the stepped portion 428 of the front plate 427. Conventionally, rotation of the terminal block was prevented by torque during assembly, and bolts were used to fix the position of the terminal block and prevent rotation. In one embodiment of the present invention, rotation of the terminal block 700 can be prevented by using a structural step, and the front cover 701 of the terminal block 700 can be fixed in position to the front plate 427 using a snap-fit ​​702 structure.

[0106] The wall created by the step at the stepped section 428 provides position guidance during assembly and prevents rotation after assembly. The snap-fit ​​702 structure prevents the terminal block 700 from detaching after assembly.

[0107] Conventionally, when assembling terminal blocks, torque was used to prevent rotation, and bolts were used to fix the position of the terminal blocks and prevent rotation. With this embodiment of the present invention, since the stepped portion 428 is used, the use of bolts and nuts can be minimized.

[0108] On the other hand, the BMS assembly 600 may be attached to the front plate 427 via an insert nut 610. The front plate 427 may be provided with consideration during plastic injection molding so that the BMS assembly 600 can be attached to the BMS mounting section 600A via the insert nut 610 without the need for a separate BMS housing.

[0109] Thus, the front plate 427 can be manufactured by injection molding with the BMS mounting portion 600A and the terminal block mounting portion 700A integrated into one unit. Plastic injection molding provides satisfactory insulation, as well as weight reduction and cost savings. Furthermore, there is no need to fasten bolts and nuts to fix the position of the terminal block 700.

[0110] From a process control perspective, bolts and nuts require continuous verification and management of torque control for fastening, the presence or absence of loosening due to product use after fastening. There is also the problem of increased cycle time due to the addition of processes for fastening and checking fastening. One aspect of the present invention proposes a structure in which the fixing structure using bolts and nuts in the battery pack 10 is minimized and the internal components are structurally assembled and fixed.

[0111] According to one aspect of the present invention, the design and control factors of the battery pack 10 can be minimized, thereby suppressing the occurrence of potential problems. Specifically, fewer design variables need to be considered for fixing the internal pack components compared to when using bolts and nuts, making it easier to manage from a process control perspective than when using bolts and nuts, and providing a battery pack 10 that does not increase the cycle 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 cycle time.

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

[0113] The energy storage system 20 may include one or more battery packs 10 according to one aspect of the present invention as described above. In particular, the energy storage system 20 may include multiple battery packs 10 according to one aspect of the present invention in a configuration that is electrically connected to one another, in order to have a large energy capacity. In addition, the energy storage system 20 according to one aspect of the present invention may further include various other components of energy storage systems that are known at the time of filing of the present invention. Furthermore, such an energy storage system 20 can 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, each containing a battery pack 10 according to one aspect of the present invention. The battery packs 10 may be configured to be housed in a rack case (not shown) arranged vertically. Multiple battery packs 10 may be mounted inside the rack case, spaced apart from each other in the vertical direction. The rack case may have a housing space with an open structure that allows multiple battery packs 10 to communicate with each other 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 on the battery rack. These plurality of battery racks may be electrically connected to each other via rack busbars (not shown).

[0115] An energy storage system 20 according to one aspect of the present invention, by including a battery pack 10 according to one aspect of the present invention, can directly utilize the advantages of the battery pack 10. Since the electrical insulation and structural safety of the battery pack 10 are ensured, the energy storage system 20 including it is highly safe. Since the structural safety of the battery pack 10 is ensured and its weight is reduced, the battery pack 10 can be easily carried and installed. Since the material costs of the battery pack 10 are reduced and productivity is improved, the production cost of the energy storage system 20 including it can be reduced.

[0116] In this specification, directional terms such as up, down, left, right, front, and back have been used. However, these terms are used merely for ease of explanation, and it will be obvious to those skilled in the art that they may vary depending on the position of the object being described and the observer's position.

[0117] Although the present invention has been described above with limited embodiments and drawings, it goes without saying that the present invention is not limited in any way, and that it can be implemented by persons with ordinary skill in the art to which the present invention pertains, with various modifications and variations within the equivalent scope of the technical idea and the appended claims. [Explanation of symbols]

[0118] 10 Battery Packs 20 Energy storage devices 100 cell assembly 101 battery cells 102 Electrode Leads 110, 120 cell stack K1 Air layer 300 Busbar Frame Assembly 310 Busbar Frame 314 Mounting plate 315 Guide Block 320 Bus Bar 400 Outer casing 410 Top Cover 412 Aperture 420 Base Plate 422 Support frame section 423 recess 424 Assembly wall 424a Insertion section 427 Front Plate 428 Stepped section 500 Reinforcement member 510 Base Clip 700 Terminal Block 701 Front Cover 702 Snap-Fit

Claims

1. A cell assembly containing multiple battery cells, An outer casing for housing the cell assembly, the outer casing having an insertion portion along its longitudinal direction, the outer surface of which is recessed inward; A rod-shaped reinforcing member inserted into the aforementioned insertion portion, Includes, The aforementioned outer casing is The base plate on which the aforementioned battery cell is mounted, The support frame portion, which is provided on both sides of the base plate and constitutes the insertion portion, Includes, The aforementioned at least one cell assembly is a plurality of cell assemblies arranged side by side, The cell assembly includes a busbar frame assembly, The support frame portion of the base plate is It is provided on the edge region extending in the arrangement direction of the cell assembly, and is provided to protrude upward at predetermined intervals along the arrangement direction of the cell assembly to support the busbar frame assembly of each cell assembly. Battery pack.

2. The base plate and the support frame are integrally injection-molded. The battery pack according to claim 1.

3. The reinforcing member is a pair of steel pipes. The battery pack according to claim 1 or 2.

4. The aforementioned outer casing is manufactured from plastic material. The reinforcing member is manufactured from a metal material. The battery pack according to claim 1 or 2.

5. Further including a base clip for fixing the position of the reinforcing member, The battery pack according to claim 1 or 2.

6. The base plate further includes a recess provided between adjacent support frame portions, Each of the cell assemblies includes a busbar frame made of an electrically insulating material. The aforementioned busbar frame is A mounting plate is placed on the upper surface of the support frame portion, A mounting guide block protruding downward from the mounting plate so as to be insertable into the corresponding recess, including, The battery pack according to claim 1.

7. The aforementioned mounting plate and the aforementioned mounting guide block are integrally injection molded with the busbar frame. The battery pack according to claim 6.

8. The recess includes a step on its upper surface, and the lower surface of the aforementioned mounting guide block has a shape corresponding to the step. The battery pack according to claim 6.

9. When the cell assembly is placed on the base plate with each of the aforementioned 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 assembly, and the assembly wall limits the insertion portion. The battery pack according to claim 6.

10. The mounting guide block and the support frame portion restrain the position of the reinforcing member in the longitudinal and height directions, and the outer casing and the busbar frame assembly are fixed to each other by the reinforcing member. The battery pack according to claim 9.

11. The assembled wall includes an upper housing wall, a lower housing wall, and a side housing wall. The reinforcing member is a rectangular parallelepiped steel pipe, The upper part of the steel pipe is in contact with the upper housing wall, the lower part of the steel pipe is in contact with the lower housing wall, and one side of the steel pipe is in contact with the side housing wall. The battery pack according to claim 9.

12. The outer casing further includes a front plate on at least one side of the base plate, The aforementioned battery pack further includes a terminal block, The front plate is fitted with a front cover that has a snap-fit ​​structure to prevent the terminal block from detaching. The battery pack according to claim 1 or 2.

13. The base plate and the front plate are injection molded as a single unit. The battery pack according to claim 12.

14. The front plate is a vertical plate-shaped plate provided on one peripheral edge 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 terminal block is exposed or shielded using the front cover, which is detachably provided on the front plate through the opening in the top cover. The battery pack according to claim 12.

15. A battery pack comprising at least one of the battery packs described in claim 1 or 2, Energy storage system.

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