High Voltage Pouch Battery Cell

Abstract

The present invention provides a pouch-type battery cell including an electrode assembly formed by alternately stacking first electrodes and second electrodes with a separator interposed therebetween, a pouch that houses the electrode assembly, and first and second electrode leads that extend from the first and second electrodes, respectively, and protrude outside the pouch, wherein the electrodes and the separator are stacked together in the axial direction, and the pouch is made of a flexible sheet and includes a peripheral member that covers the outer peripheral surface of the electrode assembly, and a pair of cover members that cover both axial ends of the electrode assembly. The pouch also provides a structure of a pouch-type battery cell and a battery pack including the same.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0156367, filed November 21, 2022, and all contents disclosed in the documents of this Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a pouch battery cell capable of outputting high voltage. [Background technology]

[0003] Secondary batteries, which are easily applicable to a wide range of products and have electrical properties such as high energy density, are commonly used not only in portable devices but also in electric vehicles or hybrid vehicles powered by electrical sources, power storage devices, etc. These secondary batteries are attracting attention as a new energy source because they not only have the primary advantage of dramatically reducing the use of fossil fuels, but also because they are environmentally friendly and improve energy efficiency by not producing any by-products from energy use.

[0004] While small mobile devices use one or two or three battery cells per device, medium to large devices such as automobiles require high output and large capacity, and therefore use medium to large battery modules or battery packs that electrically connect multiple battery cells.

[0005] Meanwhile, cylindrical, prismatic, and pouch-type battery cells are known as types of unit secondary battery cells. Since it is preferable to manufacture medium- to large-sized battery modules with small size and weight, prismatic batteries and pouch-type batteries, which can be stacked with high integration and have low weight relative to capacity, are mainly used as battery cells for medium- to large-sized battery modules. In addition, these battery modules or cylindrical battery cells can be assembled to form a battery pack.

[0006] 1 is a perspective view showing the structure of a typical pouch-type battery cell. Referring to FIG. 1, a typical pouch-type battery cell 11 includes a pouch 111 that houses and seals an electrode assembly, and an electrode lead 112 that extends from the electrode assembly and protrudes outside the pouch 111. The electrode assembly is formed by stacking positive and negative electrodes alternately in the thickness direction with a separator interposed therebetween, and the electrode lead 112 includes a positive electrode lead extending from the positive electrode and a negative electrode lead extending from the negative electrode.

[0007] 2 is a perspective view showing the structure of a battery module including the battery cell of FIG. 1. Referring to FIG. 2, the battery module 12 includes a battery cell stack formed by stacking a plurality of the battery cells 11 in the thickness direction, and a module frame 121 that accommodates the battery cell stack. At this time, bus bars that connect the plurality of electrode leads 112 to each other in series or parallel are connected, and the bus bars are connected to terminals 122 exposed to the outside of the module frame 121.

[0008] Fig. 3 is a perspective view showing the structure of a battery pack including the battery module of Fig. 2. Referring to Fig. 3, the battery pack 13 includes a plurality of the battery modules 12 and a pack frame 131 that houses the battery modules 12. The plurality of terminals 122 are connected to bus bars that connect the terminals 122 to each other in series or parallel.

[0009] As described above, battery modules and battery packs incorporating pouch-type battery cells have the disadvantages that, because they are manufactured by stacking multiple pouches, there is a high possibility of tolerances, heat is easily transmitted between the battery cells, and a fire in just one cell can spread to the entire module and pack. Furthermore, battery cells are not directly assembled into a battery pack; rather, battery cells are first assembled into a battery module, and the process of assembling the battery module to form the battery pack also creates problems, such as a complex structure and low energy density.

[0010] 4 is a plan view showing the structure of an electrode stack constituting a jelly-roll type electrode assembly. Referring to this, the jelly-roll type electrode assembly 21 to be installed inside a cylindrical battery cell is formed by winding an electrode stack in which a positive electrode 211a, a separator 212, a negative electrode 211b, and a separator 212 are sequentially stacked in a winding direction. The positive electrode 211a and the negative electrode 211b are provided with a positive electrode uncoated portion and a negative electrode uncoated portion at one and the other axial ends, respectively, where an active material layer is not coated for battery reaction.

[0011] 5 is a cross-sectional view showing the structure of a cylindrical battery cell including the jelly-roll-type electrode assembly of FIG. 4. Referring to FIG. 5, the cylindrical battery cell 22 is manufactured by inserting the electrode assembly 21 into a cylindrical battery can 221, connecting the negative electrode uncoated portion 223b to the battery can 221 via a negative electrode current collector 224b, and connecting the positive electrode uncoated portion 223a to a top cap 222 that covers the top of the battery can 221 via a positive electrode current collector 224a and an electrode tab 225 extending therefrom. The top cap 222 serves as the positive terminal of the battery cell 22, and the battery can 221 serves as the negative terminal of the battery cell 22.

[0012] Fig. 6 is a perspective view showing the structure of a battery pack including the battery cell of Fig. 5. Referring to Fig. 6, the battery pack 23 includes a plurality of the battery cells 22 and a pack frame 231 that accommodates the battery cells 22. The plurality of positive and negative terminals may be connected to each other in series or in parallel via bus bars.

[0013] Disadvantages of the cylindrical battery cells and the battery packs that house them include the fact that the current collector plate, battery can, top cap, etc. are made of metal, making them heavy; the fact that, unlike when flexible pouches are used, it is difficult to change the process; and the fact that the process is complicated, requiring many processes such as beading, crimping, and welding. Summary of the Invention [Problem to be solved by the invention]

[0014] The present invention was conceived in light of the background of the prior art described above, and its object is to provide a battery cell and battery pack structure that is simple in structure, easy to manufacture, not susceptible to tolerances, and lightweight.

[0015] A further technical object of the present invention is to provide a battery cell and battery pack structure in which heat transfer between electrodes and between cells is reduced or prevented and heat is easily dissipated.

[0016] It is yet another object of the present invention to provide a battery cell and battery pack structure in which the process and manufacturing specifications can be easily changed, and in which the output voltage and capacity can be easily changed as required when manufacturing.

[0017] The technical object of the present invention is not limited to the above-mentioned objects, and other unmentioned objects and advantages of the present invention can be understood from the following description and can be more clearly understood from the examples of the present invention. Furthermore, it can be easily understood that the objects and advantages of the present invention can be achieved by the means and combinations thereof set forth in the claims. [Means for solving the problem]

[0018] In order to solve the above problems, the present invention provides a pouch-type battery cell structure including an electrode assembly formed by alternately stacking first electrodes and second electrodes with a separator interposed therebetween, a pouch that houses the electrode assembly, and first and second electrode leads that extend from the first and second electrodes, respectively, and protrude outside the pouch, wherein the electrodes and the separator are stacked together in the axial direction, and the pouch is made of a flexible sheet and includes a peripheral member that covers the outer periphery of the electrode assembly, and a pair of cover members that cover both axial ends of the electrode assembly.

[0019] In one embodiment of the present invention, the electrodes, the separator, and the cover member may be formed in a circular shape, so that the electrode assembly and the battery cell may have a cylindrical shape.

[0020] In another embodiment of the present invention, the electrode, the separator, and the cover may be formed in a rectangular shape. The rectangle may have right angles at its vertices or may have rounded vertices in a broader sense. As a result, the electrode assembly and the battery cell may have a rectangular prism or a rectangular parallelepiped shape.

[0021] The shapes of the electrodes, the separator, and the cover member are not limited to those described above, and may be formed in any shape as long as they are formed to correspond to each other and can constitute a single columnar electrode assembly and battery cell.

[0022] In one embodiment of the present invention, the surrounding member may be formed by fusing both ends of a single sheet together at a first seal. In this case, the surrounding member may be formed by fusing the inner surfaces of both ends of the sheet together, or by fusing the inner surface of one end of the sheet to the outer surface of the other end. The sheet may be formed into various shapes, such as a rectangle or a parallelogram, as long as the sheet is formed into a pipe shape that surrounds the outer periphery of the electrode assembly by fusing both ends together as described above.

[0023] In another embodiment of the present invention, the surrounding member may be formed by fusing the inner surfaces of the ends of a plurality of sheets together with a plurality of first seal portions. For example, the surrounding member may be formed by fusing the ends of two sheets that are symmetrical to each other in a horizontal direction together.

[0024] The surrounding member may be formed by fusing the sheet to surround the electrode assembly, or the sheet may be pre-fused to form a sleeve into which the electrode assembly can be inserted.

[0025] The surrounding member and the cover member may be fused to each other at a second seal portion. Preferably, the surrounding member and the cover member are fused to each other at their respective inner surfaces. At least one of the surrounding member and the cover member may be plastically deformed in advance to facilitate the fusion. For example, the cover member may be plastically deformed so as to sink inward in the axial direction, or the surrounding member may be plastically deformed so that both axial ends thereof protrude outward in the radial direction.

[0026] In one embodiment of the present invention, the electrode lead may protrude through a slit provided in the cover member. In this case, an insulating layer may be provided in the slit to insulate and seal between the electrode lead and the cover member. The insulating layer may fusion seal between the slit and the electrode lead. The electrode lead may be connected to the electrode while coupled to the cover member, or may pass through the slit while coupled to the electrode and be coupled to the cover member.

[0027] In another embodiment of the present invention, the electrode lead may protrude between the surrounding member and the cover member. In this case, the electrode lead may be sealed together with the second seal portion. The electrode lead may be connected to the electrode before the surrounding member and the cover member are fused together.

[0028] The present invention also provides a battery pack structure including the pouch-type battery cell, a pack frame that houses the battery cell, and a bus bar to which the electrode leads are connected.

[0029] The battery pack may include a thermal insulator filling the space between the battery cells inside the frame. The thermal insulator may be made of any material that can reduce or prevent heat transfer between the battery cells. The thermal insulator may be a compressible material.

[0030] In one embodiment of the present invention, the battery cells may be arranged in the frame such that the first electrode leads face a first direction and the second electrode leads face a second direction. In this case, the bus bars may include a first bus bar connected to the first electrode leads on the first direction side of the battery cells and a second bus bar connected to the second electrode leads on the second direction side of the battery cells. In this case, the battery cells may be connected in parallel to each other between the first bus bar and the second bus bar.

[0031] In another embodiment of the present invention, the battery cells may include a first group of cells arranged in the frame with the first electrode leads facing a first direction and the second electrode leads facing a second direction, and a second group of cells arranged in the frame with the first electrode leads facing a second direction and the second electrode leads facing a third direction. In this case, the busbars may include a first busbar connected to the first electrode leads of the first group of cells on the first direction side of the battery cells, a second busbar connected to the second electrode leads of the first group of cells and the first electrode leads of the second group of cells on the second direction side of the battery cells, and a third busbar connected to the second electrode leads of the second group of cells on the third direction side of the battery cells. In this case, the first group of cells may be connected in parallel to each other between the first busbar and the second busbar, and the second group of cells may be connected in parallel to each other between the second busbar and the third busbar, so that the first group of cells and the second group of cells are connected in series to each other.

[0032] The output voltage of one of the battery cells may be the same as or half of the output voltage of the battery pack, so that the bus bar can meet the required voltage of the battery pack by simply connecting one or two groups of the battery cells in parallel, thereby simplifying the structure.

[0033] A thermally conductive layer having insulating and thermally conductive properties may be interposed between the bus bar and the frame.

[0034] The present invention also provides a vehicle including the battery pack. The construction of these electric vehicles is well known to those of ordinary skill in the art and will not be described further herein. [Effects of the Invention]

[0035] The present invention provides a battery cell and battery pack structure that is not susceptible to tolerances because it is a method of storing pouch-type battery cells as they are in a pack, with most of the cells connected in parallel with only a small number of bus bars, making the structure simple, easy to manufacture, and lightweight. The battery cells are not stacked on top of each other, but are arranged with a space between them.

[0036] Another advantage of the battery cell structure provided by the present invention is that, unlike jelly-roll-type electrode assemblies that have one positive electrode and one negative electrode, multiple positive and negative electrodes are stacked with multiple separators between them, thereby delaying or preventing heat transfer between the electrodes, and unlike batteries housed in thick battery cans, the battery is housed in a thin pouch, thereby facilitating heat dissipation.Another advantage of the battery pack structure provided by the present invention is that multiple battery cells are arranged with insulating material between them, thereby delaying or preventing heat transfer between the cells, and a thermally conductive layer is provided between the simplified bus bars and the pack frame, thereby facilitating heat dissipation.

[0037] One or two battery cells according to the present invention can output the high voltage required for a medium- to large-sized battery module or battery pack. This eliminates the need for an intermediate unit called a battery module, allowing a battery pack to be directly constructed using only the battery cells. Unlike rigid battery cans that require complex processes such as beading and crimping, the battery cells are manufactured in flexible pouches, making it easy to modify the manufacturing process and specifications. Increasing or decreasing the voltage of the battery cells is also easy by simply changing the pouch cut dimensions and the number of stacked electrodes. Furthermore, by using these high-voltage cells, most of the cells are connected in parallel, simplifying the busbar structure. This simplicity makes it easy to provide a thermally conductive layer on the busbar, simplifying the manufacture of the battery pack.

[0038] In addition to the above, the present invention can achieve various other effects, which will be explained in each embodiment, or explanations of effects that can be easily inferred by ordinary engineers will be omitted. [Brief explanation of the drawings]

[0039] [Figure 1] FIG. 1 is a perspective view showing the structure of a typical pouch-type battery cell. [Figure 2] 2 is a perspective view showing the structure of a battery module including the battery cell of FIG. 1. FIG. [Figure 3] FIG. 3 is a perspective view showing the structure of a battery pack including the battery module of FIG. 2. [Figure 4] FIG. 2 is a plan view showing the structure of an electrode stack that constitutes a jelly roll type electrode assembly. [Figure 5] 5 is a cross-sectional view showing the structure of a cylindrical battery cell including the jelly-roll type electrode assembly of FIG. 4. [Figure 6] FIG. 6 is a perspective view showing the structure of a battery pack including the battery cell of FIG. 5. [Figure 7] 1 is a cross-sectional view showing the structure of an electrode assembly according to a first embodiment of the present invention. [Figure 8] 1 is a perspective view showing the structure of an electrode assembly according to a first embodiment of the present invention. [Figure 9] 1 is a perspective view showing the structure of a battery cell according to a first embodiment of the present invention. [Figure 10] 1 is a cross-sectional view showing the structure of a battery cell according to a first embodiment of the present invention. [Figure 11] 1 is a perspective view showing the structure of a battery pack according to a first embodiment of the present invention. [Figure 12] 1 is a cross-sectional view showing the structure of a battery pack according to a first embodiment of the present invention. [Figure 13] 1 is a vertical cross-sectional view showing the structure of a battery pack according to a first embodiment of the present invention. [Figure 14] FIG. 10 is a perspective view showing the structure of an electrode assembly according to a second embodiment of the present invention. [Figure 15] FIG. 10 is a perspective view showing the structure of a battery cell according to a second embodiment of the present invention. [Figure 16] FIG. 6 is a cross-sectional view showing the structure of a battery cell according to a second embodiment of the present invention. [Figure 17] FIG. 10 is a perspective view showing the structure of a battery pack according to a second embodiment of the present invention. [Figure 18] FIG. 10 is a cross-sectional view showing the structure of a battery pack according to a second embodiment of the present invention. [Figure 19] FIG. 10 is a vertical cross-sectional view showing the structure of a battery pack according to a second embodiment of the present invention. [Figure 20] 1 is a perspective view showing the structure of an automobile according to the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0040] The above-mentioned objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily implement the technical concept of the present invention. In describing the present invention, if a detailed description of known technologies relating to the present invention is deemed to obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings are used to indicate the same or similar components.

[0041] Although terms such as "first" and "second" are used to indicate various components, it is understood that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a first component may also be a second component.

[0042] Throughout the specification, unless otherwise specified, each element may be singular or plural.

[0043] Hereinafter, when an arbitrary structure is arranged "on (or below)" a component or "above (or below)" a component, it means that the arbitrary structure is not only arranged in contact with the upper surface (or lower surface) of the component, but also that other structures may be interposed between the component and the arbitrary structure arranged above (or below) the component.

[0044] Furthermore, when a component is described as being "coupled," "coupled," or "connected" to another component, it should be understood that the components may be directly coupled or connected to each other, but that other components may be "intervening" between the components, or that each component may be "coupled," "coupled," or "connected" via other components.

[0045] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. Terms such as "comprise" or "include" in this application should not be interpreted as including all of the components or steps described in the specification, but should be interpreted as meaning that some of the components or steps may not be included, or that additional components or steps may be included.

[0046] In the entire specification, "A and / or B" means A, B or A and B unless otherwise specified, and "C to D" means C or more and D or less unless otherwise specified.

[0047] The present invention provides a pouch-type battery cell including an electrode assembly formed by alternately stacking first electrodes and second electrodes with a separator interposed therebetween, a pouch that houses the electrode assembly, and electrode leads including a first electrode lead and a second electrode lead that extend from the first electrode and the second electrode, respectively, and protrude to the outside of the pouch, wherein the first electrode, the second electrode, and the separator are stacked together in the axial direction, and the pouch is made of a flexible sheet and includes a peripheral member that covers the outer peripheral surface of the electrode assembly, and a pair of cover members that cover both axial ends of the electrode assembly. The present invention also provides a pouch-type battery cell and a battery pack structure including the pouch-type battery cell.

[0048] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings.

[0049] [Example 1] 7 is a cross-sectional view showing the structure of an electrode assembly according to Example 1 of the present invention. Referring to this figure, the electrode assembly 31 may be formed by stacking a plurality of first electrodes 311a and second electrodes 311b alternately along the axial direction with separators 312 interposed therebetween.

[0050] The electrode assembly 31 according to this embodiment has the advantage of reducing the speed and range of heat propagation in the event of electrode ignition, compared to a jelly-roll type electrode assembly formed by winding up a single long positive and negative electrode sheet. In the case of a jelly-roll type electrode assembly, heat propagates quickly through the integrated electrode sheet that extends across the axial cross section and entire length of the electrode assembly in the event of electrode ignition, which increases the risk of the entire electrode assembly igniting. However, in the case of the electrode assembly 31 according to the present invention, the electrodes 311 are provided in multiple pieces along the axial direction with separators interposed therebetween, which delays or prevents heat propagation between the electrodes 311, thereby delaying or preventing the entire electrode assembly 31 from igniting.

[0051] The electrode assembly 31 according to this embodiment also has the advantage of being able to output a high voltage due to the large number of stacked electrodes 311. This will be described later together with the structure of the battery pack.

[0052] 8 is a perspective view showing the structure of an electrode assembly according to a first embodiment of the present invention. Referring to this, the electrode 311, the separator 312, and the cover member 322 may be formed in a circular shape. As a result, the electrode assembly 31 and the battery cell may be cylindrical. The shapes of the electrode 311, the separator 312, and the cover member 322 are not limited to those described above, and may be formed in any shape as long as they are formed to correspond to each other and can form the electrode assembly 31 and the battery cell in a single columnar shape.

[0053] 9 and 10 are a perspective view and a cross-sectional view, respectively, showing the structure of a battery cell according to a first embodiment of the present invention. Referring to these figures, the battery cell 32 may include the electrode assembly 31, a pouch that houses the electrode assembly 31, and electrode leads 323 that extend from the electrodes 311 and protrude outside the pouch.

[0054] The pouch may be made of a flexible sheet and may include a surrounding member 321 that covers the outer peripheral surface of the electrode assembly, and a pair of lid members 322 that cover both axial ends of the electrode assembly.

[0055] The surrounding member 321 may be formed by fusing both ends of a single sheet together at a first seal portion 321S. In this case, the surrounding member 321 may be formed by fusing the inner surfaces of both ends of the sheet together, or by fusing the inner surface of one end of the sheet to the outer surface of the other end. The sheet may be formed into various shapes, such as a rectangle or a parallelogram, as long as it is formed into a pipe shape that surrounds the outer periphery of the electrode assembly 31 by fusing both ends together as described above.

[0056] The surrounding member 321 may be formed by fusing the sheet so that it surrounds the electrode assembly 31, or the sheet may be fused in advance to form a sleeve into which the electrode assembly 31 can be inserted.

[0057] The surrounding member 321 and the cover member 322 may be fused to each other at a second seal portion 322S. Preferably, the inner surfaces of the surrounding member 321 and the cover member 322 are fused to each other. At least one of the surrounding member 321 and the cover member 322 may be plastically deformed in advance to facilitate the fusion. For example, the cover member 322 may be plastically deformed so as to sink inward in the axial direction, or the surrounding member 321 may be plastically deformed so that both ends in the axial direction protrude outward in the radial direction.

[0058] The electrode lead 323 may protrude through a slit provided in the cover member 322. In this case, an insulating layer 324 may be provided in the slit to insulate and seal between the electrode lead 323 and the cover member 322. The insulating layer 324 may fusion seal between the slit and the electrode lead 323. The electrode lead 323 may be connected to the electrode 311 while being coupled to the cover member 322, or may pass through the slit while being coupled to the electrode 311 and coupled to the cover member 322.

[0059] The battery cell 32 according to this embodiment may include the electrode assembly 31, the pouch, and the electrode lead 323. The electrode assembly 31 may be formed by stacking the circular first electrode 311a, the circular second electrode 311b, and the circular separator 312 along the axial direction. The pouch may include the surrounding member 321 and the cover member 322. The surrounding member 321 may be a rectangular sheet that surrounds the electrode assembly 31, with the inner surfaces of both ends of the surrounding member 321 being sealed together by the first seal portion 321S. The pair of cover members 322 may be plastically deformed into a shape that is depressed inward in the axial direction, and the inner surfaces around them may be fused to the inner surfaces of both axial ends of the surrounding member 321 at the second seal portion 322S; the cover members 322 may include a slit through which the electrode lead 323 passes, and the insulating layer 324 that seals and insulates between the electrode lead 323 and the slit; the electrode lead 323 may be connected to the electrode 311 while being coupled to the cover members 322.

[0060] In the battery cell 32 according to this embodiment, the electrodes 311 are stacked in a large number along the axial direction, thereby delaying or preventing heat transfer between the electrodes 311 and outputting a high voltage. In addition, the battery cell 32 is housed in the pouch made of a flexible sheet rather than a thick battery can, which facilitates heat dissipation, simplifies manufacturing, is lightweight, and allows for easy changes to the manufacturing process and specifications.

[0061] The present invention also provides a battery pack structure including the pouch-type battery cell, a pack frame that houses the battery cell, and a bus bar to which the electrode leads are connected.

[0062] 11 to 13 are a perspective view, a cross-sectional view, and a longitudinal sectional view, respectively, showing the structure of a battery pack according to Example 1 of the present invention. Referring to these drawings, the battery pack 33 may include the battery cells 32, a pack frame 331 that houses the battery cells 32, and bus bars 332 to which the electrode leads 323 are connected.

[0063] The battery pack 33 may include a heat insulating material 333 that fills the spaces between the battery cells 32 inside the frame 331. The heat insulating material 333 may be made of any material as long as it can reduce or prevent heat transfer between the battery cells 32. The heat insulating material 333 may be made of a compressible material.

[0064] According to this embodiment, since the battery cells 32 have a circular cross section, the space between the battery cells 32 can be increased, and the space between the battery cells 32 can be filled with the insulating material 333, thereby delaying or preventing heat transfer between the battery cells 32. In addition, if the insulating material 333 has compressibility, the insulating material 333 can also function to absorb the tolerances of the battery cells 32.

[0065] The battery cells 32 may be arranged in the frame 331 such that the first electrode leads 323a face in a first direction and the second electrode leads 323b face in a second direction. In this case, the bus bars 332 may include a first bus bar 332a connected to the first electrode leads 323a on the first direction side of the battery cells 32 and a second bus bar 332b connected to the second electrode leads 323b on the second direction side of the battery cells 32. In this case, the battery cells 32 may be connected in parallel to each other between the first bus bar 332a and the second bus bar 332b.

[0066] The output voltage of one of the battery cells 32 may be the same as or half the output voltage of the battery pack 33. This allows the bus bar 332 to meet the required voltage of the battery pack 33 by simply connecting one or two groups of the battery cells 32 in parallel, thereby simplifying the structure.

[0067] A thermally conductive layer 334 having insulating and thermally conductive properties may be interposed between the bus bar 332 and the frame 331. The thermally conductive layer 334 may be made of a synthetic resin material having insulating and thermally conductive properties.

[0068] According to this embodiment, since the battery cells 32 can output a high voltage, the number of bus bars 332 can be reduced and the structure can be simplified, which simplifies the manufacture of the battery pack 33, makes it easier to change the manufacturing process and specifications, and increases the contact area between the bus bars 332 and the pack frame 331, which can be advantageous for heat dissipation.

[0069] [Example 2] The following description of the present embodiment regarding the parts not specifically explained is the same as that of the first embodiment.

[0070] 14 is a perspective view showing the structure of an electrode assembly according to Example 2 of the present invention. Referring to this figure, the electrode 411, the separator 412, and the cover member 422 may be formed in a rectangular shape. The rectangle may have right angles at each vertex, or may have rounded vertices in a broader sense of the word. Therefore, the electrode assembly 41 and the battery cell 42 may have a rectangular prism or rectangular parallelepiped shape.

[0071] 15 and 16 are a perspective view and a cross-sectional view, respectively, showing the structure of a battery cell according to Example 2 of the present invention. Referring to these figures, the surrounding member 421 may be formed by fusing the inner surfaces of the respective ends of a plurality of sheets together with a plurality of first sealing portions 421S. For example, the surrounding member 421 may be formed by fusing the respective ends of two sheets that are horizontally symmetrical to each other.

[0072] The electrode lead 423 may protrude between the surrounding member 421 and the cover member 422. In this case, the electrode lead 423 may be sealed together by the second seal portion 422S. The electrode lead 423 may be connected to the electrode 411 before the surrounding member 421 and the cover member 422 are fused to each other.

[0073] The battery cell 42 according to this embodiment may include the electrode assembly 41, the pouch, and the electrode lead 423. The electrode assembly 41 may be formed by stacking the first electrode 411a, the second electrode 411b, and the separator 412, each of which has a square shape with rounded corners, along the axial direction. The pouch may include the surrounding member 421 and the cover member 422. The surrounding member 421 is a pair of rectangular sheets that surround the electrode assembly 41. The inner surfaces of both ends may be formed by fusing together with a pair of the first seal portions 421S; the pair of cover members 422 may be plastically deformed into a shape that sinks inward in the axial direction, and the inner surfaces around them may be fused to the inner surfaces of both axial ends of the surrounding member 421 with the second seal portion 422S; the electrode lead 423, while connected to the electrode 411, may pass through the second seal portion 422S and protrude to the outside of the pouch, and be sealed together with the surrounding member 421 and the cover member 422.

[0074] The battery cell 42 according to this embodiment has the advantages of ease of arrangement and connection and ensuring energy density, since the shape of the pouch and the position of the first sealing portion 421S are symmetrical and the overall shape is formed close to a rectangular parallelepiped.

[0075] 17 to 19 are a perspective view, a horizontal cross-sectional view, and a vertical cross-sectional view, respectively, showing the structure of a battery pack according to Example 2 of the present invention. Referring to these drawings, the battery cells 42 may include a first group of cells arranged in the frame 431 so that the first electrode leads 423a face a first direction and the second electrode leads 423b face a second direction, and a second group of cells arranged in the frame 431 so that the first electrode leads 423a face the second direction and the second electrode leads 423b face a third direction. In this case, the bus bar 432 may include a first bus bar 432a connected to the first electrode leads 423a of the first group of cells on the first direction side of the battery cell 42, a second bus bar 432b connected to the second electrode leads 423b of the first group of cells and the first electrode leads 423a of the second group of cells on the second direction side of the battery cell 42, and a third bus bar 432c connected to the second electrode leads 423b of the second group of cells on the third direction side of the battery cell 42. In this case, the first group of cells may be connected in parallel to each other between the first bus bar 432a and the second bus bar 432b, and the second group of cells may be connected in parallel to each other between the second bus bar 432b and the third bus bar 432c, so that the first group of cells and the second group of cells may be connected in series to each other.

[0076] The output voltage of one of the battery cells 42 may be the same as or half the output voltage of the battery pack 43. This allows the bus bar 432 to meet the required voltage of the battery pack 43 by simply connecting one or two groups of the battery cells 42 in parallel, thereby simplifying the structure.

[0077] According to this embodiment, the rectangular shape of the battery cells 42 allows them to be accommodated in the pack frame 431 with higher integration, thereby enabling the battery pack 43 to have a high energy density. In addition, the arrangement of the bus bars 432 has the advantage that the positive and negative terminals of the battery pack 43 can face in the same direction.

[0078] The present invention also provides a vehicle including the battery pack.

[0079] 20 is a perspective view showing the structure of the automobile according to the present invention. Referring to this, the battery pack (P) can be installed inside the automobile (V) as a power source. The structure of these electric automobiles is well known to ordinary engineers, so it will not be described separately in this specification.

[0080] It should be understood that the above-described embodiments are illustrative in all respects and are not limiting, and the scope of the present invention is defined by the following claims rather than the above detailed description. All modifications and variations within the meaning and scope of the following claims, as well as equivalent concepts, should be construed as being included within the scope of the present invention.

[0081] Although the present invention has been described above with reference to illustrative drawings, the present invention is not limited to the embodiments and drawings disclosed in this specification, and various modifications may be made by those skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration of the present invention are not explicitly described in the above description of the embodiments of the present invention, it is natural that the effects that can be predicted by the configuration should also be recognized. [Explanation of symbols]

[0082] 11 Battery Cells 111 pouches 112 Electrode Lead 12 Battery Module 121 Module Frame Terminal 122 13 Battery pack 131 Pack Frame 21 Electrode assembly 211 Electrode 211a positive electrode 211b negative electrode 212 Separation membrane 22 battery cells 221 Battery Can 222 Top Cap 223 Uncoated electrode 223a Positive electrode uncoated area 223b Negative electrode plain area 224 Current collector plate 224a Positive current collector plate 224b Negative current collector plate 225 Electrode Tab 23 Battery pack 231 Pack Frame 31 Electrode assembly 311 Electrode 311a 1st electrode 311b 2nd electrode 312 Separation membrane 32 battery cells 321 Surrounding Materials 321S First seal part 322 Cover member 322S Second seal part 323 Electrode Lead 323a First electrode lead 323b Second electrode lead 324 Insulation Layer 33 Battery pack 331 Pack Frame 332 Busbar 332a 1st bus bar 332b 2nd bus bar 333 Insulation 334 Thermal Conduction Layer 41 Electrode assembly 411 Electrode 411a 1st electrode 411b 2nd electrode 412 Separation membrane 42 battery cells 421 Surrounding parts 421S First seal part 422 Cover member 422S Second seal part 423 Electrode Lead 423a First electrode lead 423b Second electrode lead 424 Insulating Layer 43 Battery Pack 431 Pack Frame 432 Busbar 432a 1st bus bar 432b 2nd bus bar 432c 3rd bus bar 433 Insulation 434 Thermal Conduction Layer P Battery pack V Automobile X1 Length direction Y1 Thickness direction / Width direction Z1 Height direction X2 Length / Circumference Y2 Radial direction Z2 Height direction / Thickness direction / Axial direction

Claims

1. a pouch-type battery cell equipped with electrode leads; a pack frame that houses the battery cells; a bus bar to which the electrode lead is connected; A battery pack including: The battery cell is an electrode assembly formed by alternately stacking first electrodes and second electrodes with a separator interposed therebetween; a pouch that accommodates the electrode assembly; Including, the electrode leads include a first electrode lead and a second electrode lead extending from the first electrode and the second electrode, respectively, and protruding to the outside of the pouch; the first electrode, the second electrode, and the separation membrane are stacked in the axial direction; The pouch comprises: It consists of a flexible sheet, a peripheral member that covers an outer peripheral surface of the electrode assembly; a pair of cover members for covering both axial ends of the electrode assembly; Including, Battery pack.

2. The first electrode, the second electrode, the separation membrane, and the cover member are formed in a circular shape. The battery pack according to claim 1 .

3. The first electrode, the second electrode, the separation membrane, and the cover member are formed in a rectangular shape. The battery pack according to claim 1 .

4. the first electrode, the second electrode, the separation membrane, and the cover member are formed in a rectangular shape with rounded vertices; The battery pack according to claim 1 .

5. The peripheral member is formed by fusing both end portions of a single sheet together at a first seal portion. The battery pack according to claim 1 .

6. The peripheral member is formed by fusing the inner surfaces of both end portions of the sheet to each other. The battery pack according to claim 5 .

7. The peripheral member is formed by fusing an inner surface of one end of the sheet and an outer surface of the other end of the sheet together. The battery pack according to claim 5 .

8. The peripheral member is formed by fusing the inner surfaces of the respective ends of a plurality of sheets together with a plurality of first seal portions. The battery pack according to claim 1 .

9. The surrounding member and the lid member are fused to each other at a second seal portion. The battery pack according to claim 1 .

10. The electrode lead protrudes through a slit provided in the lid member. The battery pack according to claim 1 .

11. an insulating layer is provided in the slit to insulate and seal between the electrode lead and the cover member; The battery pack according to claim 10.

12. The electrode lead protrudes between the surrounding member and the cover member. The battery pack according to claim 9.

13. a heat insulating material filling spaces between the battery cells inside the pack frame; The battery pack according to claim 1 .

14. the battery cell is disposed in the pack frame such that the first electrode lead faces a first direction and the second electrode lead faces a second direction; The bus bar is a first bus bar connected to the first electrode lead on the first direction side of the battery cell; a second bus bar connected to the second electrode lead on the second direction side of the battery cell; Including, The battery pack according to claim 1 .

15. The output voltage of one of the battery cells is the same as or half of the output voltage of the battery pack. The battery pack according to claim 14.

16. The battery cell is a first group of cells arranged in the pack frame such that the first electrode leads face a first direction and the second electrode leads face a second direction; a second group of cells arranged in the pack frame such that the first electrode leads face a second direction and the second electrode leads face a third direction; Including, The bus bar is a first bus bar connected to the first electrode leads of the first group of cells on the first direction side of the battery cells; a second bus bar connected to the second electrode leads of the first group of cells and the first electrode leads of the second group of cells on the second direction side of the battery cells; a third bus bar connected to the second electrode leads of the second group of cells on the third direction side of the battery cells; Including, The battery pack according to claim 1 .

17. The output voltage of one of the battery cells is the same as or half of the output voltage of the battery pack. The battery pack according to claim 16.

18. a thermally conductive layer having insulating properties and thermal conductivity is interposed between the bus bar and the pack frame; The battery pack according to claim 1 .

19. A battery pack comprising the battery pack according to any one of claims 1 to 18. car.

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