Battery Pack Capable of Surface Pressure Loading

Abstract

The present invention is a battery pack capable of receiving a surface pressure load, comprising: a battery module formed by stacking a plurality of battery cells; an upper case that surrounds and pressurizes the upper part of the battery module; a lower case manufactured to correspond to the upper case, which surrounds the lower part of the battery module and is coupled to the upper case; a coupling unit that detachably connects the upper case and the lower case; and a plurality of compression units provided in the battery module to maintain the surface pressure applied to the battery module according to a set standard.

Description

Technology Field

[0001] The present invention relates to a battery pack capable of surface pressure loading by applying surface pressure to a pouch cell without a fixing member through an integrated pack design. Background Technology

[0002] Recently, lithium-ion batteries are being widely used not only in small devices such as portable electronic equipment but also in medium-to-large devices such as automobiles and power storage systems. When lithium-ion batteries are used in such medium-to-large devices, a large number of batteries are electrically connected to increase capacity and output. In particular, pouch-type batteries are frequently used in these medium-to-large devices due to advantages such as ease of stacking and light weight.

[0003] In the past, when a cell assembly was prepared by stacking multiple pouch-type secondary batteries and cartridges and housing it in a pack case to form a battery pack, end plates were provided at the outermost ends of both sides in the stacking direction of the cell assembly.

[0004] These end plates, primarily composed of metal, can protect and secure the secondary battery and cartridge and maintain surface pressure.

[0005] In addition, to prevent damage to the electrode lead welds caused by the movement of the battery cells, the pouch-type secondary batteries were inserted into a cell frame and stacked, and then the cell assembly was assembled using bolts and nuts.

[0006] Meanwhile, secondary batteries possess electrical characteristics that allow for high applicability across a diverse range of product categories and high energy density. These secondary batteries are being applied not only to portable electronic devices but also to electric or hybrid vehicles powered by electric sources, power storage devices, and the like.

[0007] Battery packs applied to electric vehicles and the like have a structure in which multiple battery modules, each containing multiple battery cells, are connected to obtain high output. Furthermore, each individual battery cell functions as an electrode assembly and enables repeated charging and discharging through electrochemical reactions between its components, which include positive and negative current collectors, separators, active materials, and electrolytes.

[0008] In addition, with the recent increase in the need for large-capacity structures, including their utilization as energy storage sources, there is a growing demand for battery packs with a multi-module structure that aggregates multiple battery modules in which multiple secondary batteries are connected in series or parallel.

[0009] Meanwhile, in the case of battery cells in battery modules, a swelling phenomenon occurs during repeated charging and discharging. To account for this swelling phenomenon, conventional battery modules position battery cells at a certain distance apart during stacking, or place compression pads between the cells to support the cells during swelling.

[0010] However, spacing the aforementioned compression pads or battery cells reduces the volume that cells can occupy in the battery module. Reducing the volume occupied by cells in the battery module presents a problem of decreasing the energy density of the battery cells.

[0011] In addition, using compression pads between battery cells complicates the manufacturing process of the battery module and increases the manufacturing cost.

[0012] In addition, if compression pads are not used and the batteries are arranged at regular intervals, there is a problem of damaging the batteries because they cannot be secured against swelling or external impacts.

[0013] In addition, batteries for vehicle power supply and batteries for electronic device power supply have traditionally been operated using lead-acid batteries. However, there is a recent trend of shifting the technology base to lithium batteries due to reasons such as product intelligence, lifespan, and weight reduction. Lithium battery cells are classified into NCM, LFP, etc., based on the cathode material, and are distinguished into pouch, cylindrical can, prismatic can, etc., based on the form factor.

[0014] Conventionally, starting batteries or deep-cycle batteries were manufactured using lead, and vehicle starting batteries have disadvantages such as lifespan, intelligence, and heavy weight.

[0015] Furthermore, when using pouch cells such as NCM or LFP, changes in temperature and pressure during use may exceed the original assembly tolerance range, placing stress on product components and potentially causing durability issues.

[0016] Furthermore, when using pouch cells, the internal cathode, anode, and separator are stacked; if the pressure and thickness specified in the initial shipment standards are not guaranteed, the distance lithium ions travel becomes longer, resulting in a situation where a portion of the initial performance cannot be utilized.

[0017] Therefore, when conventional battery packs utilize pouch cells, they manage initial surface pressure and pressure during swelling by configuring a method of applying surface pressure through separate fixing members, such as separate long bolt configurations. Prior art literature

[0018] Republic of Korea Published Patent No. 10-2021-0090387 (July 20, 2021) Republic of Korea Registered Patent No. 10-2018721 (September 9, 2019) The problem to be solved

[0019] Accordingly, the present invention has been devised to solve the above-mentioned problems. The objective of the present invention is limited to the design of a battery pack based on a lithium battery using a pouch cell, and is to provide a battery pack capable of surface pressure load that implements initial surface pressure through the design of a fixed structure of the product itself with an additional fixed shape configuration without a separate fixing member.

[0020] However, the technical problems to be solved by the present invention are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0021] The present invention was created to improve upon the problems of the prior art as described above, and may comprise a battery pack capable of receiving a surface pressure load, comprising: a battery module formed by stacking a plurality of battery cells; an upper case that surrounds and pressurizes the upper part of the battery module; a lower case manufactured to correspond to the upper case, which surrounds the lower part of the battery module and is coupled to the upper case; a coupling unit that detachably combines the upper case and the lower case; and a plurality of compression units provided in the battery module to maintain the surface pressure applied to the battery module according to a set standard.

[0022] In addition, in one embodiment, the upper case may include a plurality of ribs that protrude downward from a portion of the inner side and press the upper part of the battery module so that a pressure set on the battery module is applied uniformly.

[0023] In addition, in one embodiment, the compression unit may be interposed between a plurality of battery cells in the battery module and pressurize at a preset pressure to achieve a preset compression ratio.

[0024] In addition, in one embodiment, the upper case and the lower case can each be joined through a snap-fit ​​connection.

[0025] Additionally, in one embodiment, the coupling unit may include: coupling holes formed at corresponding positions on the upper case and the lower case, respectively; and fastening bolts that are coupled to each of the coupling holes and coupled to the lower case while pressing the upper case.

[0026] Additionally, in one embodiment, the rib may include a plurality of pressure areas formed at set intervals to press the upper part of the battery module; and a plurality of dispersion areas formed inwardly recessed between the pressure areas corresponding to the plurality of pressure areas to disperse pressure. Effects of the invention

[0027] According to one embodiment of the present invention, the design is limited to a battery pack based on a lithium battery using a pouch cell, and has the effect of implementing an initial surface pressure through a rib, a coupling unit, and a compression unit formed on an upper case without a separate fixing member.

[0028] However, the effects obtainable from the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description below. Brief explanation of the drawing

[0029] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. FIG. 1 is a perspective view of a battery pack capable of surface pressure load according to an embodiment of the present invention. Figure 2 is an exploded view of a battery pack capable of surface pressure load. Figure 3 is a diagram illustrating the interior of a battery pack capable of surface pressure load. Figure 4 is a drawing showing the inside of the upper case of the battery pack. Figure 5 is a drawing showing the inner side of the lower case of the battery pack. Figure 6 is a detailed drawing of the ribs of the upper case. Specific details for implementing the invention

[0030] Below, with reference to the attached drawings, embodiments of the present invention are described in detail so that those skilled in the art can easily implement the invention. However, since the description of the present invention is merely an example for structural or functional explanation, the scope of the rights of the present invention should not be interpreted as being limited by the embodiments described in the text. That is, since the embodiments are subject to various modifications and may take various forms, the scope of the rights of the present invention should be understood to include equivalents capable of realizing the technical concept. Furthermore, the objectives or effects presented in the present invention do not imply that a specific embodiment must include all of them or only such effects; therefore, the scope of the rights of the present invention should not be understood as being limited by them.

[0031] The meaning of the terms described in this invention should be understood as follows.

[0032] Terms such as "first" and "second" are intended to distinguish one component from another, and the scope of rights shall not be limited by these terms. For example, the first component may be named the second component, and similarly, the second component may be named the first component. When a component is referred to as being "connected" to another component, it should be understood that it may be directly connected to that other component, or that there may be other components in between. Conversely, when a component is referred to as being "directly connected" to another component, it should be understood that there are no other components in between. Meanwhile, other expressions describing the relationship between components, such as "between" and "exactly between," or "adjacent to" and "directly adjacent to," shall be interpreted in the same manner.

[0033] A singular expression should be understood to include a plural expression unless the context clearly indicates otherwise, and terms such as "include" or "have" are intended to specify the existence of the set-up features, numbers, steps, actions, components, parts, or combinations thereof, and should be understood not to preclude the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0034] Unless otherwise defined, all terms used herein have the same meaning as generally understood by those skilled in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted as having meanings consistent with the context of the relevant technology and should not be interpreted as having an ideal or overly formal meaning unless explicitly defined in this invention.

[0035] FIG. 1 is a perspective view of a battery pack capable of surface pressure load according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of a battery pack capable of surface pressure load, FIG. 3 is a drawing showing the interior of a battery pack capable of surface pressure load, FIG. 4 is a drawing showing the interior of an upper case of a battery pack, FIG. 5 is a drawing showing the interior of a lower case of a battery pack, and FIG. 6 is a drawing showing the ribs of an upper case in detail.

[0036] As illustrated in FIGS. 1 to 6, the present invention may include a battery pack capable of receiving a surface pressure load, comprising a battery module (100), an upper case (200), a lower case (300), a coupling unit (400), and a compression unit (500).

[0037] The battery module (100) can be formed by stacking a plurality of battery cells (30).

[0038] The upper case (200) can surround and pressurize the upper part of the battery module (100).

[0039] The upper case (200) may include a rib (210).

[0040] The ribs (210) are composed of multiple ribs and are formed to protrude downward from a part of the inner side, so that the upper part of the battery module (100) can be pressed so that the pressure set on the battery module (100) is applied uniformly.

[0041] The rib (210) may include a pressure area (212) and a dispersion area (214).

[0042] A plurality of pressure areas (212) are formed at set intervals to apply pressure to the upper part of the battery module (100). Specifically, the upper case (200), which is coupled to the lower case (300) by the coupling unit (400), can apply pressure through the coupling unit (400) and press the upper part of the battery module (100) with the set pressure using the plurality of pressure areas (212).

[0043] A plurality of dispersion areas (214) are formed in a state of being inwardly recessed between a plurality of pressure areas (212) corresponding to a plurality of pressure areas (212) so as to disperse pressure. Specifically, the dispersion areas (214) are inwardly recessed between a plurality of pressure areas (212) to provide a plurality of spaces of a set size, thereby helping to ensure that the pressure applied by the pressure areas (212) to the battery module (100) is evenly distributed.

[0044] The composition or structure of the rib (210) can be freely manufactured considering interference and durability.

[0045] The lower case (300) is manufactured to correspond to the upper case (200) and can be coupled to the upper case (200) while surrounding the lower part of the battery module (100).

[0046] The upper case (200) and the lower case (300) can each be joined by a snap-fit ​​connection.

[0047] The coupling unit (400) can detachably combine the upper case (200) and the lower case (300).

[0048] The coupling unit (400) may include a coupling hole (410) and a fastening bolt (420).

[0049] The coupling hole (410) can be formed at corresponding positions on the upper case (200) and the lower case (300).

[0050] The fastening bolt (420) is connected to each of the connecting holes (410) and can be connected to the lower case (300) while pressing the upper case (200).

[0051] A plurality of compression units (500) are provided in the battery module (100) to maintain the surface pressure applied to the battery module (100) according to a set standard.

[0052] The compression unit (500) can be interposed between a plurality of battery cells (30) in the battery module (100) and pressurized to a preset pressure to achieve a preset compression ratio.

[0053] A battery pack (10) according to one embodiment of the present invention is limited to a battery pack (10) based on a lithium battery with battery cells, and can achieve an initial surface pressure through an upper case (200), a compression unit (500), a coupling unit (400), etc., without adding a separate fixing member, by adding a fixing shape configuration to a configuration that fits a preset standard without a separate fixing member.

[0054] In addition, pressure can be applied to maintain a constant thickness even when the battery cell (30) is used for an initial thickness and a certain lifespan. The method of applying pressure involves applying pressure to the upper part of the battery module (100) through the formed ribs (210) of the upper case (200), and applying pressure through the load required for assembly as well as the configuration of the battery module (100) by connecting the upper case (200) and the lower case (300), which are made of die-casting material, with a connecting unit (400).

[0055] At this time, for the purpose of self-protection of the battery cell (30) and pressure inversion, a compression unit (500) in the form of a compression pad is inserted between the battery cells (30) to calculate the corresponding value through the compression ratio, thereby securing initial performance.

[0056] As described above, the detailed description of the preferred embodiments of the present invention disclosed is provided to enable those skilled in the art to implement and practice the present invention. Although the present invention has been described with reference to preferred embodiments, those skilled in the art will understand that various modifications and changes can be made to the present invention without departing from the scope of the invention. For example, those skilled in the art may utilize each configuration described in the embodiments described above in combination with one another. Accordingly, the present invention is not intended to be limited to the embodiments shown herein, but to be given the broadest scope consistent with the principles and novel features disclosed herein.

[0057] The present invention may be embodied in other specific forms without departing from the spirit and essential features of the invention. Accordingly, the above detailed description should not be interpreted restrictively in all respects but should be considered exemplary. The scope of the invention shall be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the invention are included within the scope of the invention. The invention is not intended to be limited to the embodiments shown herein, but to be given the broadest possible scope consistent with the principles and novel features disclosed herein. Furthermore, embodiments may be constructed by combining claims that are not explicitly related in the claims, or by including them as new claims through amendments made after filing. Explanation of the symbols

[0058] 10 : Battery pack 30 : Battery cell 100 : Battery module 200 : Upper case 210 : Liv 212 : Pressurized area 214 : Dispersion area 300 : Lower case 400 : Combination unit 410 : Connection hole 420 : Fastening bolt 500 : Compression unit

Claims

Claim 1 A battery pack capable of applying surface pressure, comprising: a battery module formed by stacking a plurality of battery cells; an upper case that surrounds and applies pressure to the upper part of the battery module; a lower case manufactured to correspond to the upper case, that surrounds the lower part of the battery module, and that is coupled to the upper case; a coupling unit that detachably connects the upper case and the lower case; and a compression unit provided in a plurality on the battery module to maintain the surface pressure applied to the battery module according to a set standard; wherein the upper case includes a plurality of ribs formed to protrude downward from a part of the inner side to apply pressure to the upper part of the battery module so that a set pressure is applied uniformly to the battery module; and wherein the ribs include a plurality of pressure areas formed at a set interval to apply pressure by directly contacting the upper part of the battery module. A battery pack capable of surface pressure load, comprising: a plurality of dispersion regions formed inwardly recessed as non-pressure spaces between the plurality of pressure regions that do not come into direct contact with the battery module, corresponding to the plurality of pressure regions, and dispersing pressure; wherein the plurality of pressure regions pressurize the upper part of the battery module with a set pressure while the upper case, which is coupled to the lower case by the coupling unit, applies a set pressure through the coupling unit, and the dispersion regions provide a plurality of spaces of a set size that are inwardly recessed between the plurality of pressure regions, thereby ensuring that the pressure applied by the pressure regions to the battery module is evenly distributed. Claim 2 delete Claim 3 A battery pack capable of surface pressure load according to claim 1, wherein the compression unit is interposed between a plurality of battery cells in the battery module and pressurizes with a preset pressure to achieve a preset compression ratio. Claim 4 A battery pack capable of surface pressure load according to claim 1, characterized in that the upper case and the lower case are each joined through a snap-fit ​​connection. Claim 5 A battery pack capable of surface pressure load according to claim 1, wherein the coupling unit comprises: coupling holes formed at corresponding positions of the upper case and the lower case, respectively; and fastening bolts coupled to each of the coupling holes and coupled to the lower case while pressing the upper case. Claim 6 delete

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