Battery module and battery pack including same

Abstract

The present disclosure provides a battery module comprising: a cell assembly comprising a plurality of cells, each cell comprising a main body portion configured to accommodate an electrode assembly and an electrode lead electrically connected to the electrode assembly, the plurality of cells being arranged relative to each other in a first direction; the side plate extends to be arranged on at least one side of the battery cell assembly in the first direction; and a pressing member provided on the inner side of the side plate and configured to apply a pressure to a portion of the cell assembly adjacent to the electrode lead.

Description

Technical Field

[0001] The disclosed technology generally relates to a battery module comprising multiple rechargeable and discharging secondary battery cells and a battery pack comprising the battery module. Background Technology

[0002] With the increasing demand for mobile devices, electric vehicles, energy storage devices, and other technologies, the demand for secondary battery cells as energy sources is also growing rapidly. In secondary batteries, the conversion between chemical energy and electrical energy is reversible, allowing for repeated charging and discharging of the secondary battery cells.

[0003] A battery cell may include an electrode assembly consisting of a positive electrode plate, a negative electrode plate, a separator, etc., and an electrolyte. Battery cells are available in various types, such as pouch-type, prismatic, or cylindrical can-type.

[0004] Multiple cells can be arranged in a predetermined pattern and incorporated into a battery module or battery pack, which can be used in a variety of applications such as electric vehicles and energy storage systems (ESS). Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] During charging and discharging, secondary cell swelling may occur, which refers to the volume expansion of the cell. This swelling may be caused by solid expansion due to electrochemical reactions or by gas generation under high temperature conditions. When swelling occurs, uneven surface pressure between cells within the battery module may lead to cell deformation and shorten the lifespan of both the cells and the battery module.

[0007] To address the issue of air expansion, compression components such as pads can be placed around the battery cells to alleviate uneven surface pressure between them.

[0008] However, if the electrode assembly exhibits thickness variations due to the position of the electrode plates constituting the assembly, the compression pad may have limitations in its ability to completely eliminate surface pressure unevenness. When such surface pressure unevenness occurs in the cell, the cell's capacity may drop sharply or its resistance may increase sharply in the areas of low surface pressure.

[0009] In one aspect of the disclosed technology, a battery module and a battery pack including the battery module are provided, which can extend the service life by reducing unevenness of surface pressure applied to the battery cell.

[0010] In one aspect of the disclosed technology, a battery module and a battery pack including the battery module are provided, which can limit the sharp decrease in cell capacity or the sharp increase in resistance caused by uneven surface pressure.

[0011] In one aspect of the disclosed technology, a battery module and a battery pack including the battery module are provided, which employ a structure that limits the decrease in cell capacity and / or the increase in resistance and can also reduce the impact on energy density.

[0012] The disclosed technology can be widely applied in green technology fields such as electric vehicles, battery charging stations, and other solar and wind power generation utilizing batteries. Furthermore, the disclosed technology can be used in eco-friendly electric vehicles, hybrid vehicles, and similar applications that prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0013] (II) Technical Solution

[0014] In one aspect of the disclosed technology, the battery module may include: a cell assembly comprising a plurality of cells, each cell including a body portion configured to house an electrode assembly and a body portion of an electrode lead electrically connected to the electrode assembly, the plurality of cells being arranged relative to each other along a first direction; a side plate extending to be disposed on at least one side of the cell assembly in the first direction; and a pressure member disposed on the inner side of the side plate and configured to apply pressure to a portion of the cell assembly adjacent to the electrode lead.

[0015] According to one embodiment, the main body may include: a uniform thickness region at or near the center of the main body; and a reduced thickness region closer to the electrode lead than the uniform thickness region. The side plate may include: a first portion opposite to the uniform thickness region in the first direction; and a second portion opposite to the reduced thickness region in the first direction. The pressure member may be disposed in at least a portion of the second portion and may not be disposed in at least a portion of the first portion.

[0016] According to one embodiment, the pressurizing component may not be provided in the first part.

[0017] According to one embodiment, the side plate may include a first side plate and a second side plate respectively disposed on two opposite sides of the battery cell assembly. The distance between the first side plate and the second side plate at the center of the side plate is called a first distance, and the minimum distance between a pressure-applying component disposed on the first side plate and a pressure-applying component disposed on the second side plate is called a second distance. Here, the first distance is greater than the second distance.

[0018] According to one embodiment, the difference between the average thickness of the electrode assembly in the uniform thickness region and the minimum thickness of the electrode assembly in the thickness reduction region is called the maximum thickness deviation. Here, the first distance and the second distance can satisfy the following ranges.

[0019] L1 - (dTm × N) ≤ L2 ≤ L1 - dTm

[0020] Where L1 is the first distance, L2 is the second distance, dTm is the maximum thickness deviation, and N is the number of cells included in the cell assembly.

[0021] According to one embodiment, the pressurizing component may be integrated into the side plate.

[0022] According to one embodiment, the pressurizing component may be integrally formed with the side plate.

[0023] According to one embodiment, the pressurizing member may be formed as a protrusion on the inner side surface of the side plate.

[0024] According to one embodiment, the pressurizing member may be formed as an inclined surface or a curved surface on the inner side of the side plate.

[0025] According to one embodiment, the side plate may include: a first portion opposite to a uniform thickness region of the main body in the first direction; and a second portion opposite to a thickness reduction region of the main body in the first direction, wherein the pressure member may be formed as the second portion of the side plate.

[0026] According to one embodiment, the pressurizing component may have a constant thickness in a second direction in which the electrode lead extends from the electrode assembly.

[0027] According to one embodiment, the pressurizing member may have a shape such that, in a second direction in which the electrode lead extends from the electrode assembly, the outer side of the pressurizing member protrudes further into the cell assembly than the inner side of the pressurizing member.

[0028] According to one embodiment, the side plate may include a first side plate and a second side plate respectively disposed on two opposite sides of the cell assembly, and the pressurizing component may be disposed on the first side plate and the second side plate respectively.

[0029] According to one embodiment, the side plate may form part of a module housing, the module housing may include a housing body, the housing body including: a first side plate; a second side plate; and a bottom plate connecting the first side plate and the second side plate, the housing body may be manufactured in sections of at least two parts, and the at least two parts of the housing body may be coupled to each other in a second direction in which the electrode leads extend from the electrode assembly.

[0030] According to one embodiment, the side panel may include: a first portion opposite to a uniform thickness region of the main body in the first direction; and a second portion opposite to a thickness reduction region of the main body in the first direction and connected to the first portion, wherein the at least two components may be separated at the boundary between the first portion and the second portion.

[0031] According to one embodiment, the electrode leads can extend from each of two opposite sides of the electrode assembly along a second direction. The thickness reduction regions are located on each of two opposite sides of the body portion along the second direction, and the pressure-applying member can be disposed on the side plate opposite each thickness reduction region.

[0032] According to one embodiment, the electrode leads can extend from one side of the electrode assembly along a second direction. The thickness reduction region can be located on one side of the main body along the second direction. The pressure-applying member can be disposed on one side of the side plate along the second direction, opposite to the thickness reduction region located on one side of the main body along the second direction.

[0033] According to one aspect of the disclosed technology, a battery pack may include: a plurality of battery modules; and a battery pack housing configured to house the plurality of battery modules, wherein at least one of the plurality of battery modules may include: a cell assembly including a plurality of cells, each cell including a body portion configured to house an electrode assembly and an electrode lead electrically connected to the electrode assembly, the plurality of cells being arranged relative to each other along a first direction; a side plate extending to be disposed on at least one side of the cell assembly in the first direction; and a pressure member disposed inside the side plate and configured to apply pressure to a portion of the cell assembly adjacent to the electrode lead.

[0034] (III) Beneficial Effects

[0035] Based on the embodiments, the lifespan of battery modules and / or battery packs can be extended.

[0036] In addition, it can address the problem of a sharp drop in the capacity or a sharp increase in the resistance of the battery cells installed in the battery module.

[0037] In addition, when a pressurizing component is installed on the inside of the side plate, the energy density reduction of the battery module caused by the installation of the pressurizing component can be minimized. Attached Figure Description

[0038] The specific aspects, features, and advantages of the disclosed technology are illustrated in the following detailed description with reference to the accompanying drawings.

[0039] Figure 1 This is a perspective view showing a battery module based on an embodiment of the disclosed technology.

[0040] Figure 2 It is shown Figure 1 The image shows an exploded perspective view of the battery module.

[0041] Figure 3 This is a perspective view showing a battery cell based on an embodiment of the disclosed technology.

[0042] Figure 4 It shows along Figure 3 A cross-sectional view of the battery cell taken from the I-I' line.

[0043] Figure 5a It is a perspective view showing the state in which the battery cell assembly and the housing body are joined together based on an embodiment of the disclosed technology.

[0044] Figure 5b It shows along Figure 5a A cross-sectional view of the battery cell assembly taken from line II-II' before it is pressurized by the pressurizing component.

[0045] Figure 5c It is shown Figure 5b A cross-sectional view of the battery cell assembly under pressure by a pressurizing component.

[0046] Figure 6 This is a graph showing the thickness deviation ΔT of the electrode assembly of a battery cell based on an embodiment of the disclosed technology.

[0047] Figure 7 This is a diagram showing the thickness variation of an electrode assembly in a portion adjacent to the electrode leads, based on an embodiment of the disclosed technology.

[0048] Figure 8 (a) and (b) show the electrode plates; Figure 8 (a) is a plan view showing an electrode plate based on an embodiment of the disclosed technology. Figure 8 (b) is a cross-sectional view.

[0049] Figure 9a It is shown Figures 5a to 5c A perspective view of a variant of the outer casing and pressurizing components shown.

[0050] Figure 9b It is shown Figure 9a The image shows a perspective view of the outer shell body in a separated state.

[0051] Figure 9c It is along Figure 9a A cross-sectional view taken from line III-III'.

[0052] Figure 10a and Figure 10b They are shown respectively Figure 9c Cross-sectional view of the variant example shown.

[0053] Figure 11 This is an exploded perspective view of a battery module based on another embodiment of the disclosed technology.

[0054] Figure 12 It is along Figure 11 A cross-sectional view taken from the IV-IV' line.

[0055] Figure 13 and Figure 14 It is shown Figure 12 A cross-sectional view of a variant example.

[0056] Figure 15a and Figure 15b This is a diagram of a battery cell based on another embodiment of the disclosed technology.

[0057] Figure 16 This is a perspective view of a battery pack based on an embodiment of the disclosed technology.

[0058] Explanation of reference numerals in the attached figures:

[0059] 100: Battery module; 110: Cell assembly

[0060] 120: Battery cell; 121: Bag (outer packaging material)

[0061] 122: Main body

[0062] 122a: Uniform thickness region

[0063] 122b: Reduced thickness region

[0064] 123: Sealing part; 124: Electrode assembly

[0065] 124a: Positive electrode plate; 124b: Negative electrode plate

[0066] 124c: Diaphragm; 125: Electrode tab

[0067] 126: Electrode lead; 126a: Positive lead

[0068] 126b: Negative lead; 130: Pressure-applying component

[0069] 140: Busbar assembly; 141: Support plate

[0070] 145: Busbar 150: Module Housing

[0071] 151: Outer shell body 151a: First body

[0072] 151b: Second subject; 151c: Third subject

[0073] 152: Base plate 153: Side plate

[0074] 154: First side panel 155: Second side panel

[0075] 154a, 155a: Central section; 154b, 155b: Pressurized section

[0076] 154c, 155c: Outer side; 156: Outer shell cover

[0077] 200: Battery pack 210: Battery pack casing

[0078] A1: Part One A2: Part Two

[0079] CC: Current collector; CL: Cutting line

[0080] L1: First distance L2: Second distance

[0081] R1: Coated part; R11: Center part

[0082] R12: Edge area; R2: Uncoated area

[0083] R21: First uncoated portion; R22: Second uncoated portion

[0084] RM: Slurry; TP: Thickness of pressurized component. Detailed Implementation

[0085] Embodiments of the disclosed technology will be described with reference to the accompanying drawings.

[0086] In the accompanying drawings, the same reference numerals denote the same elements. For clarity, redundant or known descriptions that might obscure the understanding of the disclosed technology have been omitted. It should be understood that even if the same reference numerals are used in different embodiments, the components shown do not necessarily represent the same embodiment.

[0087] The present disclosure will now be described in detail with reference to the accompanying drawings. However, these are merely examples, and the present disclosure is not limited to the specific embodiments described herein.

[0088] Figure 1 This is a perspective view of the battery module 100 based on an embodiment. Figure 2 yes Figure 1 An exploded perspective view of the battery module 100 shown.

[0089] Reference Figure 1 and Figure 2 The battery module 100 based on the embodiment may include: a cell assembly 110, wherein a plurality of cells 120 are arranged along a first direction X, and each of the plurality of cells 120 includes an electrode assembly (see reference). Figure 4 The main body 122 of the cell assembly 110 and the electrode lead 126 electrically connected to the electrode assembly; the side plate 153, which covers both sides (e.g., two opposite sides) of the cell assembly 110 in the first direction X; and the pressure member 130, which is disposed inside the side plate 153 and configured to apply pressure to the portion of the cell assembly 110 adjacent to the electrode lead 126.

[0090] The battery module 100 according to the embodiment may include a busbar assembly 140, the busbar assembly 140 including: a busbar 145 connected to the electrode leads 126 of the battery cell 120; and a support plate 141 supporting the busbar 145. The battery module 100 according to the embodiment may further include a module housing 150 covering at least a portion of the battery cell assembly 110.

[0091] The cell assembly 110 can be formed by arranging a plurality of cells 120 along a first direction X. In one embodiment, the plurality of cells 120 can be stacked with their wide faces facing each other. For example, the plurality of cells 120 can be stacked along the first direction X. However, in some embodiments, the plurality of cells 120 can also have a shape that is stacked along the direction of gravity (e.g., the third direction Z).

[0092] Each cell 120 can be configured to house an electrode assembly within a bag (outer packaging material) 121. Figure 4 The battery cell 120 is a pouch-type cell (124). The pouch 121 may include a body portion 122 that houses the electrode assembly 124. Each cell 120 may include electrode leads 126 exposed outside the pouch 121. The electrode leads 126 may be electrically connected to the electrode assembly 124.

[0093] In the cell 120 of this disclosure, the width direction (length direction) refers to the direction from which the electrode lead 126 extends from the electrode assembly ( Figure 4 The second direction Y of the extension of 124), the thickness direction refers to the first direction X perpendicular to the wide surface of bag 121, and the height direction (up and down direction or gravity direction) refers to the third direction Z perpendicular to the width direction and the thickness direction.

[0094] The cell assembly 110 may include a compression pad 115 to absorb the expansion of the cell 120 due to air expansion. The compression pad 115 may be disposed between at least a portion of the cells 120, or between the cell 120 and the side plate 153. The compression pad 115 can be compressed when the cell 120 expands, thereby absorbing the expansion of the cell 120. The compression pad 115 may also be elastically deformable. The compression pad 115 can suppress the overall volume increase of the cell assembly 110 during air expansion. The compression pad 115 may be made of polyurethane foam, but its material or structure is not limited to this. The compression pad 115 may have dimensions corresponding to the main body 122, but its dimensions can also be varied.

[0095] The busbar assembly 140 may include a conductive busbar 145 electrically connected to the electrode leads 126 of the battery cell 120 and an electrically insulating support plate 141. The support plate 141 may be disposed between the plurality of battery cells 120 and the conductive busbar 145 to support the busbar 145. The support plate 141 may electrically insulate the busbar 145 from the pockets 121 of the battery cell 120. For example, the busbar 145 may be snap-fitted to the support plate 141 or welded to the support plate 141. However, the manner in which the busbar 145 is attached to the support plate 141 can be varied.

[0096] Busbar assembly 140 can be positioned opposite to the electrode leads 126 of battery cell 120 to be electrically connected to multiple electrode leads 126. For example, when the electrode leads 126 are located at both ends of the second direction Y of battery cell 120, busbar assembly 140 can be located at both ends of the second direction Y of battery cell 120 to be connected to the electrode leads 126.

[0097] Electrode leads 126 can pass through the support plate 141 of the busbar assembly 140 and be coupled to the busbar 145 on the outside of the busbar assembly 140. The busbar 145 may include a bonding hole 146 through which the electrode leads 126 pass and are coupled. The electrode leads 126 can be soldered to the busbar 145 while passing through the bonding hole 146. Multiple cells 120 can be electrically connected in series and / or in parallel through multiple busbars 145.

[0098] Busbar assembly 140 may include connection terminals 147 for electrically connecting the busbar to an external component. Battery cell 120 may be electrically connected to the external component via connection terminals 147. Connection terminals 147 may be exposed to the external component through through-holes 157a formed in end plate 157.

[0099] The module housing 150 may have a structure that covers at least a portion of the cell assembly 110. The module housing 150 may form at least a portion of the appearance of the battery module 100.

[0100] The module housing 150 can have various shapes or segmented structures. For example, the module housing 150 may include: a housing body 151 with a cross-sectional shape having an opening on one side; and a housing cover 156 that cooperates with the housing body 151 to form an internal space. The housing cover 156 may cover the top surface of the cell assembly 110. The housing body 151 may include: a base plate 152 that supports the lower part of the cell assembly 110; and side plates 153 that extend from both ends of the base plate 152 along a third direction Z and support the sides of the cell assembly 110. The module housing 150 may have a structure in which end plates 157 are attached to the front and rear parts of the module housing 150 along its length. The end plates 157 may be attached to the two sides of the cell 120 on which the electrode leads 126 are provided, for example, on both sides of the module housing 150 in the second direction Y.

[0101] The inner side of the module housing 150 may be provided with a battery cell assembly 110. At least one side of the module housing 150 may serve as a heat sink to dissipate the heat generated by the battery cell 120 to the outside. At least a portion of the module housing 150 may be made of a material with high thermal conductivity, such as metal. For example, the module housing 150 may contain aluminum. However, the material of the housing body 151 is not limited to this; various materials can be used, even if they are not metal, as long as they have similar strength and thermal conductivity to metal.

[0102] On the other hand, although Figure 1 and Figure 2 The module housing 150 is shown as having a structure that completely surrounds the outer surface of the cell assembly 110, but the module housing 150 may also be configured to expose at least one side of the cell assembly 110 to the outside. For example, the module housing 150 may also have a structure that does not cover the lower surface of the cell assembly 110.

[0103] The pressurizing member 130 can be disposed on the inner side of the side plate 153 and can pressurize the cell assembly 110 at the portion adjacent to the electrode leads 126. The pressurizing member 130 can have a shape that protrudes from the inner side of the side plate 153 into the cell assembly 110. The pressurizing member 130 can be configured to pressurize a thin region of the electrode assembly 124 in the cell 120. By pressurizing the thin region of the electrode assembly 124, the pressurizing member 130 can not only compensate for the thickness of the thin portion of the electrode assembly 124, but also increase the pressure in the thin region of the electrode assembly 124. Therefore, the pressurizing member 130 can limit the sharp decrease in capacity or the sharp increase in resistance of the cell 120 due to surface pressure imbalance.

[0104] Figure 3 This is a perspective view of the battery cell 120 based on the embodiment. Figure 4 It shows along Figure 3 A cross-sectional view taken from the I-I' line.

[0105] Reference Figure 3 and Figure 4 The battery cell 120 may be a pouch-type battery cell that houses the electrode assembly 124 inside a pouch 121 of flexible material.

[0106] The battery cell 120 may include: a body portion 122 that internally houses an electrode assembly 124; a sealing portion 123 that extends from at least a portion of the outer surface of the body portion 122 and seals the body portion 122; and an electrode lead 126 that is electrically connected to the electrode assembly 124.

[0107] The bag 121 can be formed in the form of a container to provide internal space for accommodating the electrode assembly 124 and the electrolyte. For example, the bag 121 can be made of an outer sheet laminated with a resin such as polypropylene and an aluminum laminate. However, the materials constituting the bag 121 can be varied.

[0108] The bag 121 may include a main body 122 and a sealing portion 123. The main body 122 is formed in the form of a container and provides an internal space of a predetermined shape (e.g., hexahedron) for accommodating the electrode assembly 124 and the electrolyte. The main body 122 may include: a uniform thickness region 122a, including the center of the main body 122; and a reduced thickness region 122b, disposed closer to the electrode lead 126 than the uniform thickness region 122a.

[0109] The sealing portion 123 may extend from at least a portion of the outer surface of the main body portion 122. The sealing portion 123 may be formed as a flange extending outward from at least a portion of the outer surface of the main body portion 122. For example, when a bag 121 is formed by folding an outer sheet, the sealing portion 123 may have a shape extending from three of the four faces of the main body portion 122. Conversely, when a bag 121 is formed by overlapping two outer sheets, the sealing portion 123 may have a shape extending from all four faces of the main body portion 122. The sealing portion 123 may have the outer sheets constituting the bag 121 overlapping or stacked. The sealing portion 123 may include portions where the overlapping outer sheets join to seal the main body portion 122. The joining of the sealing portion 123 may be achieved by heat fusion, but is not limited to this method.

[0110] The electrode assembly 124 may include multiple electrode plates EP and multiple separators 124c, and is housed within the internal space of the main body 122. The electrode plates EP may include a positive electrode plate 124a and a negative electrode plate 124b. The electrode assembly 124 may be configured such that the positive electrode plate 124a and the negative electrode plate 124b are stacked with the separators 124c sandwiched between them, with their wide surfaces facing each other. The multiple positive electrode plates and the multiple negative electrode plates may each include electrode tabs 125. The electrode tabs 125 may include a positive electrode tab 125a disposed on the positive electrode plate 124a and a negative electrode tab 125b disposed on the negative electrode plate 124b. The electrode tabs 125 may be connected to electrode leads 126 in a manner where they are in contact with each other of the same polarity.

[0111] Electrode leads 126 may be exposed to external components through a portion of the sealing portion 123. For example, electrode leads 126 may have a shape extending from electrode assembly 124 along a second direction Y and exposed to the outside of the sealing portion 123. Electrode leads 126 may include: a positive electrode lead 126a connected to the positive electrode tab 125a of the positive electrode plate 124a; and a negative electrode lead 126b connected to the negative electrode tab 125b of the negative electrode plate 124b.

[0112] In one embodiment, the sealing portion 123 can be divided into a first sealing portion 123a and a second sealing portion 123b. The first sealing portion 123a is located on the flange where the electrode lead 126 is provided, and the second sealing portion 123b is located on the flange where the electrode lead 126 is not provided. In the first sealing portion 123a, the electrode lead 126 may be covered by an insulating portion 127. The insulating portion 127 can improve the electrical insulation performance between the electrode lead 126 and the bag 121, and can improve the sealing performance of the sealing area. The insulating portion 127 may include an insulating film.

[0113] exist Figure 3In the case of the battery cell 120 shown, with the second direction Y as a reference, electrode leads 126 are respectively provided on both sides of the main body 122 of the battery cell 120. Specifically, Figure 3 The diagram shows a configuration where the positive lead 126a and the negative lead 126b are arranged facing opposite directions. However, the positive lead 126a and the negative lead 126b can also be arranged on one side of the main body 122, facing the same direction and spaced apart from each other (see reference). Figure 15a and Figure 15b ).

[0114] In one embodiment, the cell 120 may be configured such that a portion of the seal 123 is folded at least once to improve the engagement reliability of the seal 123 and reduce the area occupied by the seal 123. For example, a second seal 123b without electrode leads 126 may include a folded portion 123c folded along the length direction of the cell 120 (e.g., a second direction Y). The folded portion 123c may have a shape folded by at least one folding process. In one embodiment, the cell 120 may include at least one tape 129 covering the folded portion 123c to limit the unfolding of the folded portion 123c due to rising internal pressure of the cell 120. The tape 129 may have a shape that wraps around the folded portion 123c.

[0115] Figure 5a This is a perspective view showing the state in which the cell assembly 110 and the housing body 151 are joined together in the embodiment. Figure 5b It is along Figure 5a The cross-sectional view taken along line II-II' shows the state of the cell assembly 110 before being pressurized by the pressurizing component 130. Figure 5c It is shown schematically. Figure 5b A cross-sectional view of the battery cell assembly 110 under pressure by the pressure-applying component 130. Figure 5b The state of the battery cell assembly 110 before it is pressurized is shown in order to clearly show the part where the pressurizing component 130 pressurizes the battery cell assembly 110. Figure 5c Only the positional relationship between the cell assembly 110 and the pressurizing component 130 is shown when the cell assembly 110 is pressurized by the pressurizing component 130; the deformation state of the cell assembly 110 is not specifically shown. Figure 5c Under pressure, the cell assembly 110 can be compressed at a position opposite to the pressure member 130, corresponding to the thickness of the pressure member 130.

[0116] The cell assembly 110 may include multiple cells 120. (See reference...) Figure 3 and Figure 4As described, the main body 122 of the cell 120 may include: a uniform thickness region 122a, including the center of the main body 122; and a thickness reduction region 122b, which is disposed closer to the electrode lead 126 than the uniform thickness region 122a.

[0117] Simultaneously refer to Figures 3 to 5c After coating with a slurry (including active substances, conductive materials, and binders) (see reference) Figure 8 In the region of (b) RM), the electrode assembly 124 may include a region of uniform thickness and a region with a smaller thickness compared to the region of uniform thickness. The uniform thickness region 122a and the reduced thickness region 122b of the main body 122 can be determined based on the thickness of the electrode assembly 124 located inside the main body 122. The uniform thickness region 122a and the reduced thickness region 122b are used to coat the slurry (including the active material) Figure 8 Based on the region of (b) RM or the region of the electrode plate EP stack, the electrode tab 125 may not be included in the thickness reduction region 122b. The uniform thickness region 122a and the thickness reduction region 122b as a whole may have a quadrilateral shape.

[0118] The uniform thickness region 122a can be defined as the portion of the main body 122 facing the electrode assembly 124 that has a uniform thickness with respect to the electrode assembly 124. Here, "uniform thickness" is not limited to having the same thickness, but rather means that the thickness of the electrode assembly 124 is within a predetermined range (e.g., within 3%).

[0119] The thickness reduction region 122b refers to the portion of the main body 122 that faces the area where the thickness of the electrode assembly 124 disposed on the inner side of the main body 122 is reduced overall compared to the uniform thickness region 122a. For example, the thickness reduction region 122b may include a region where the thickness of the electrode assembly 124 exceeds a predetermined range (e.g., within 3%) and is less than the thickness of the uniform thickness region 122a. Here, the predetermined range is not fixed at a specific value and can be varied according to the thickness deviation of the current collector (metal foil) constituting the electrode plate EP, the thickness deviation of the slurry including active materials, etc. The thickness reduction region 122b may be the portion of the main body 122 facing the area of ​​the electrode assembly 124 with a smaller thickness when pressure is applied to the electrode assembly 124.

[0120] The thickness reduction region 122b can be defined as the area with the slurry coated on the electrode plate EP. Figure 8The thickness reduction region 122b is the portion of the main body 122 opposite to the region of RM (b). The thickness reduction region 122b can extend from the end of the electrode plate EP toward the inside of the electrode plate EP. The thickness reduction region 122b can extend from one side of the main body 122 opposite to the end position P1 of the first electrode plate (e.g., the positive electrode plate) toward the inside of the first electrode plate, or it can extend from the other side of the main body 122 opposite to the end position P19 of the second electrode plate (e.g., the negative electrode plate) toward the inside of the second electrode plate.

[0121] Reference Figures 5a to 5c The side plate 153 can be provided as part of the module housing 150. The module housing 150 can include a housing body 151, which includes a first side plate 154, a second side plate 155, and a bottom plate 152 connecting the first side plate 154 and the second side plate 155.

[0122] The outer casing 151 may include: a base plate 152 that supports the lower part of the battery cell assembly 110; and a side plate 153 that extends from both ends of the base plate 152 along a third direction Z and supports the sides of the battery cell assembly 110.

[0123] Side plates 153 may include a first side plate 154 and a second side plate 155 respectively disposed on both sides of the cell assembly 110. The first side plate 154 may cover one side of the cell assembly 110 in a first direction X, and the second side plate 155 may cover the other side of the cell assembly 110 in the first direction X. For example, the first side plate 154 may extend upward from one end of the base plate 152, and the second side plate 155 may extend upward from the other end of the base plate 152. However, the first side plate 154 and the second side plate 155 are not limited to a configuration connected to the base plate 152. For example, the module housing 150 or the housing body 151 may also not include the base plate 152 (see reference). Figure 11 ).

[0124] The side plate 153 may include: a first portion A1, which is opposite to the uniform thickness region 122a of the main body 122 in the first direction X; and a second portion A2, which is opposite to the thickness reduction region 122b of the main body 122 in the first direction X. The side plate 153 may further include: a third portion A3, which is disposed outside the second portion A2 in the second direction Y.

[0125] The pressurizing member 130 can be disposed on the inner side of the side plate 153, and can pressurize the cell assembly 110 at the portion adjacent to the electrode lead 126. The pressurizing member 130 can have a shape that protrudes from the inner side of the side plate 153 into the cell assembly 110.

[0126] The side plate 153 may include a first side plate 154 and a second side plate 155 respectively disposed on both sides of the cell assembly 110, and the pressure member 130 may be disposed on the first side plate 154 and the second side plate 155 respectively.

[0127] The pressure-applying member 130 may be disposed in at least a portion of the second portion A2 of the side plate 153, and may not be disposed in at least a portion of the first portion A1 of the side plate 153. In some embodiments, the pressure-applying member 130 may have a shape that does not cover the entire uniform thickness region in the second direction Y in which the electrode lead 126 extends. For example, the pressure-applying member 130 may be disposed at a position away from the uniform thickness region 122a and cover the thickness reduction region 122b. In the second direction Y, the width W of the pressure-applying member 130 may have the same width as the thickness reduction region 122b (see reference). Figure 8 The value corresponding to La of (b).

[0128] The thickness of the electrode assembly 124 opposite to the thickness reduction region 122b (refer to) Figure 7 T2) can be less than the thickness of the electrode assembly 124 opposite to the uniform thickness region 122a (see reference). Figure 7 (T1). The pressurizing member 130 may have a preset thickness TP, thus compensating for at least a portion of the thickness of the electrode assembly 124 opposite to the thickness reduction region 122b. In some embodiments, the thickness TP of the pressurizing member 130 may compensate for the thickness of the electrode assembly 124 opposite to the uniform thickness region 122a (see T1). Figure 7 The thickness of T1) and the thickness of the electrode assembly 124 opposite to the thickness reduction region 122b (refer to T1) Figure 7 At least a portion of the difference between T2 and T2.

[0129] Furthermore, the pressurizing component 130 can increase the pressure on the electrode assembly 124 opposite to the thickness reduction region 122b, thereby compensating for at least a portion of the pressure in the thickness reduction region 122b. The thickness T2 of the electrode assembly 124 opposite to the thickness reduction region 122b is smaller than the thickness T1 of the electrode assembly 124 opposite to the uniform thickness region 122a. Therefore, when the cell 120 undergoes gas expansion, the space in which the electrode assembly 124 opposite to the thickness reduction region 122b can expand is greater than the space in which the electrode assembly 124 opposite to the uniform thickness region 122a can expand.

[0130] Therefore, the surface pressure or applied pressure exerted by adjacent cells 120, etc., on the electrode assembly 124 opposite the thickness reduction region 122b can be less than the surface pressure or applied pressure exerted on the electrode assembly 124 opposite the uniform thickness region 122a. The pressurizing member 130 can compensate for the reduced thickness of the electrode assembly 124 opposite the thickness reduction region 122b, thereby ensuring that the surface pressure or applied pressure exerted on the electrode assemblies 124 opposite the uniform thickness region 122a and the thickness reduction region 122b, respectively, has similar or uniform values. Therefore, the pressurizing member 130 can maintain the pressure exerted on the electrode assembly 124 opposite the thickness reduction region 122b at a level similar to the pressure exerted on the electrode assembly 124 opposite the uniform thickness region 122a.

[0131] As described above, the pressurizing component 130 can compensate for at least a portion of the thickness and / or pressure of the thickness reduction region 122b.

[0132] Based on the embodiments, the pressurizing member 130 may not be located opposite to the first portion A1. If the pressurizing member 130 is provided throughout the entire body portion 122 along the second direction Y extending along the electrode lead 126, the pressurizing member 130 may also be provided on the first portion A1. In this case, since the pressurizing member 130 pressurizes the uniform thickness region 122a of the body portion 122, which does not require thickness compensation and / or pressure compensation, the thickness of the battery module in the first direction X increases, resulting in a decrease in the space efficiency of the battery module. Furthermore, when the pressurizing member 130 pressurizes both the thickness-reduced region 122b and the uniform thickness region 122a, the thickness compensation effect and / or pressure compensation effect of the pressurizing member 130 in the thickness-reduced region 122b may be reduced. Conversely, in the embodiment, since the pressurizing component 130 is mainly disposed in the thickness reduction region 122b that requires thickness compensation and / or pressure compensation, it can not only fully realize the thickness compensation and / or pressure compensation effect of the pressurizing component 130 in the thickness reduction region 122b, but also solve the problem of reduced internal space efficiency of the battery module caused by the setting of the pressurizing component 130.

[0133] The side plate 153 may include a first side plate 154 and a second side plate 155 respectively disposed on both sides of the cell assembly 110. When the distance between the first side plate 154 and the second side plate 155 at the center of the side plate 153 is called a first distance L1, and the minimum distance between the pressure member 130 disposed on the first side plate 154 and the pressure member 130 disposed on the second side plate 155 is called a second distance L2, the first distance L1 may be greater than the second distance L2. The pressure member 130 has a preset thickness TP, thus it can compensate for at least a portion of the thickness of the cell assembly 110 at the second portion A2 of the side plate 153 opposite to the thickness reduction region 122b. The thickness of the cell assembly 110 opposite to the second portion A2 of the side plate 153 may correspond to the second distance L2, and the thickness of the cell assembly 110 opposite to the first portion A1 of the side plate 153 may correspond to the first distance L1.

[0134] For a battery cell 120, when the difference between the average thickness T1 of the electrode assembly 124 in the uniform thickness region 122a and the minimum thickness T2 of the electrode assembly 124 in the thickness reduction region 122b is called the maximum thickness deviation “dTm”, the first distance L1 and the second distance L2 can satisfy the range defined by the following formula (Formula 1). The first distance L1 and the second distance L2 can be as follows: Figure 5c The values ​​shown are measured with the cell assembly 110 pressurized by the pressurizing component 130. The first distance L1 and the second distance L2 can also be measured with the cell assembly 110 assembled into the module housing 150.

[0135] [Formula 1] L1 - (dTm × N) ≤ L2 ≤ L1 - dTm

[0136] Here, L1: first distance, L2: second distance, dTm: maximum thickness deviation, N: number of cells 120 included in the cell assembly 110.

[0137] In some embodiments, the second distance L2 may be equal to or greater than the first distance L1 minus the total maximum thickness deviation dTm of all cells 120 in the cell assembly 110. The second distance L2 may be equal to or less than the first distance L1 minus the maximum thickness deviation dTm of one cell 120.

[0138] The first distance L1 can be equal to the sum of the second distance L2 and the thickness TP of the two pressurizing components 130. Therefore, when the pressurizing components 130 disposed on the first side plate 154 and the second side plate 155 have the same thickness, the thickness TP of each pressurizing component 130 can be calculated as (L1-L2) / 2. However, the pressurizing component 130 can also be disposed only on one of the first side plate 154 and the second side plate 155, and the thickness of the pressurizing component 130 disposed on the first side plate 154 can also have different values ​​than the thickness of the pressurizing component 130 disposed on the second side plate 155.

[0139] On the other hand, the thickness T2 of the electrode assembly 124 in the thickness reduction region 122b can have a minimum value at the end position P1 of the electrode plate EP. However, depending on the process of coating the electrode plate EP with slurry (or active material), the position where the thickness T2 of the electrode assembly 124 is minimum or the thickness deviation is maximum can be located at a position slightly farther from the end position P1 of the electrode plate EP.

[0140] The pressure member 130 may have a constant thickness in the second direction Y in which the electrode lead 126 extends from the electrode assembly 124. The pressure member 130 may have a stepped shape relative to the side plate 153. However, the shape of the pressure member 130 is not limited to this and may also have an inclined surface or a curved surface (see reference). Figures 9a to 10b Furthermore, the pressurizing member 130 may also have a shape in which the outer side of the pressurizing member 130 protrudes further into the cell assembly 110 than the inner side in a second direction Y from which the electrode lead 126 extends from the electrode assembly 124 (see reference). Figures 9a to 10b ).

[0141] When the pressure member 130 is made of a non-compressible material, the thickness TP of the pressure member 130 can be defined as the value measured in the uncompressed state. When the pressure member 130 is made of a compressible material, the thickness TP of the pressure member 130 can be defined as the value measured when the pressure member 130 is compressed to a preset value (e.g., 60%, 80% or similar).

[0142] When the pressurizing component 130 is an incompressible, non-compressible material (e.g., a rigid synthetic resin), the pressurizing component 130 can have the same or similar thickness in both the pressurized and unpressurized states. On the other hand, when the pressurizing component 130 is a compressible, compressible material (e.g., polyurethane foam), the thickness of the pressurizing component 130 in the pressurized state is less than its thickness in the unpressurized state. Even for a compressible material pressurizing component 130, it is difficult to compress further or the amount of further compression is very small when it is under a preset compression value. With this in mind, the thickness TP of the compressible material pressurizing component 130 can be set to a value measured under a preset compression value (e.g., 60%, 80%, or a similar value).

[0143] In the second direction Y extending from the electrode assembly 124, the width W of the pressure member 130 can be 0.5 to 2.0 times the width of the thickness reduction region 122b. The width W of the pressure member 130 can be 0.7 to 1.5 times, 0.8 to 1.2 times, or 0.8 to 1.0 times the width of the thickness reduction region 122b. In some embodiments, the pressure member 130 can cover more than half of the thickness reduction region 122b to compensate for the thickness of the thickness reduction region 122b and increase surface pressure. Furthermore, the pressure member 130 can cover most or all of the thickness reduction region 122b. If the width W of the pressure member 130 is too small (e.g., less than 0.5 times the width of the thickness reduction region 122b), the pressure member 130 cannot adequately cover the thickness reduction region 122b, thus reducing the effectiveness of thickness compensation and increased surface pressure in the thickness reduction region 122b. On the other hand, if the width W of the pressure-applying component 130 is too large (for example, greater than 2.0 times the width of the thickness reduction region 122b), the pressure-applying component 130 will cover a large area of ​​the uniform thickness region 122a, resulting in an increase in the thickness of the cell 120, and the thickness compensation effect of the thickness reduction region 122b may also be reduced.

[0144] The height of the pressurizing component 130 can be greater than or equal to the height of the electrode plate EP in the electrode assembly 124. For example, the height of the pressurizing component 130 can be greater than or equal to the height of the positive electrode plate 124a. The pressurizing component 130 can cover the entire electrode assembly 124 in the thickness reduction region 122b in the height direction of the cell 120, i.e., the third direction Z. For example, the height of the pressurizing component 130 can have a value corresponding to the height of the thickness reduction region 122b or the height of the side plate 153. However, the height of the pressurizing component 130 can also be set to more than half the height of the electrode plate EP in the electrode assembly 124.

[0145] Since the pressure-applying component 130 can contact the main body 122 of the battery cell 120, the pressure-applying component 130 can contain an electrically insulating material to achieve insulation from the battery cell 120. When the insulation of the main body 122 of the battery cell 120 is compromised, current may flow to the pressure-applying component 130, which is in contact with the main body 122. In this case, the pressure-applying component 130 may act as an abnormal current channel. With this in mind, the pressure-applying component 130 can be insulating. The insulation performance of the pressure-applying component 130 can be the same as or higher than that of the insulation performance of the bag 121 or the diaphragm. For example, the insulation performance of the pressure-applying component 130 can also be set to 80 megohms or higher. However, when other insulating materials (e.g., compression pad 115) are provided between the pressure-applying component 130 and the main body 122, the electrical insulation of the pressure-applying component 130 may not be necessary, or its insulation level may be lower than the above-mentioned level. For example, the material of the pressure-applying component 130 can be polyurethane, silicone, rubber, or similar materials, but various modifications are possible.

[0146] The pressure-applying component 130 can be attached to the side plate 153. The pressure-applying component 130 can be attached to the second portion A2 of the side plate 153 so as to face the thickness reduction region 122b. For example, the pressure-applying component 130 can be composed of a gasket or the like and attached to the thickness reduction region 122b. Alternatively, the pressure-applying component 130 can also have a configuration where it is liquid-coated onto the second portion A2 of the side plate 153 and then cured. For example, the pressure-applying component 130 can be made of a curable liquid substance such as hot melt adhesive or thermal adhesive.

[0147] like Figures 3 to 5c As shown, when the electrode leads 126 have a shape that extends from both sides of the electrode assembly 124 along the second direction Y, the thickness reduction regions 122b can be located on both sides of the main body 122 in the second direction Y, and the pressure members 130 can be respectively provided on both sides of the side plate 153 to be opposite to each thickness reduction region 122b.

[0148] For example, the pressurizing components 130 can be respectively disposed in the second portion A2 on one side of the second direction Y and the second portion A2 on the other side of the second direction Y in the first side plate 154, and can also be respectively disposed in the second portion A2 on one side of the second direction Y and the second portion A2 on the other side of the second direction Y in the second side plate 155. In some embodiments, a total of four pressurizing components 130 can be disposed on the side plate 153. The pressurizing components 130 disposed on both sides of the side plate 153 in the second direction Y can be spaced apart from each other by the first portion A1.

[0149] Figure 6 This illustrates the electrode assembly in the battery cell 120 based on an embodiment. Figure 4A graph showing the thickness deviation ΔT of 124). Figure 7 This is a diagram showing the thickness variation of the electrode assembly 124, where the electrode leads 126 are provided. Figure 7 This shows the internal state of cell 120 when it is pressurized by pressure pad CP. Figure 8 (a) and (b) show the electrode plate EP. Specifically, Figure 8 (a) is a plan view of electrode plate EP. Figure 8 (b) is a cross-sectional view of electrode plate EP.

[0150] Combination Figure 4 Reference Figure 6 The thickness of the electrode assembly 124 of the battery cell 120 varies depending on its position. Figure 6 The upper diagram marks 19 measurement positions, P1 to P19, along the second direction Y extending from the electrode lead 126 to measure the thickness of the electrode assembly 124. The lower diagram shows the thickness deviation ΔT measured at each of the measurement positions P1 to P19 in millimeters (mm). Measurement position P1 is the end position of the first electrode plate (e.g., the positive electrode plate), measurement position P19 is the end position of the second electrode plate (e.g., the negative electrode plate), and measurement position P10 is the center XC of the electrode assembly 124. Figure 6 The graph shows the thickness deviation ΔT of the electrode assembly 124 at each measurement location relative to the center P10 of the electrode assembly 124.

[0151] like Figure 6 As shown in the diagram, it can be confirmed that the electrode assembly 124 has a relatively uniform thickness in the uniform thickness region 122a of the main body 122, while the thickness of the electrode assembly 124 decreases in the thickness reduction region 122b near the electrode lead 126. Because... Figure 6 The electrode leads 126 of the battery cell 120 shown are located on both sides of the main body 122, so the thickness reduction region 122b is formed on both sides of the main body 122.

[0152] like Figure 7 As shown, the thickness of the electrode assembly 124 decreases in the thickness reduction region 122b. In some embodiments, the thickness T2 of the electrode assembly 124 in the thickness reduction region 122b may be less than the thickness T1 of the electrode assembly 124 in the uniform thickness region 122a. As an example, the thickness T2 of the electrode assembly 124 in the thickness reduction region 122b may decrease closer to the electrode lead 126. The thickness T2 of the electrode assembly 124 in the thickness reduction region 122b may have a minimum value at the end position P1 of the electrode plate EP.

[0153] Reference Figure 8 (a) and Figure 8(b) explains the reason for the reduction in thickness of the electrode assembly 124 in the portion adjacent to the electrode lead 126.

[0154] The electrode plates (positive and negative plates) EP constituting the electrode assembly 124 are formed by coating a current collector CC made of aluminum or copper with a paste RM. The paste RM contains an active material, a conductive material, and a binder, and can be coated on both sides of the current collector CC. The electrode plate EP can be divided into a coated area R1 with the paste RM containing the active material and an uncoated area R2 without the paste RM. The uncoated area R2 has a predetermined width Lb and is cut into a predetermined shape to form an electrode tab. Figure 4 (125). The coated portion R1 can form the wide surface of the electrode plate EP. The coated portion R1 and the uncoated portion R2 can be cut with the cutting line CL as a reference so that they each have a height corresponding to one electrode plate EP.

[0155] The uncoated portion R2 may include a first uncoated portion R21 disposed on one side of the electrode plate EP and a second uncoated portion R22 disposed on the other side of the electrode plate EP. The first uncoated portion R21 may be used as a positive electrode tab in the positive electrode plate, and the second uncoated portion R22 may be used as a negative electrode tab in the negative electrode plate.

[0156] Because the slurry RM is in a fluid state, it will flow down from the two side edges R12 under its own weight, thus having a shape where the thickness of the two side edges R12 is less than the thickness of the center R11. For example, the two side edges R12 can have an inclined shape. In this case, the two side edges R12 can have the minimum thickness at the boundary line BL with the uncoated portion R2. The two side edges R12 are formed on a predetermined width La. When the electrode plates EP are stacked to form the electrode assembly 124, the two side edges R12 can be opposite to the thickness reduction region 122b of the main body 122, and the width La of the edge R12 can be equal to the width of the pressure member ( Figure 5b Corresponding to W).

[0157] Refer again Figure 7In the end position P1 of the thickness reduction region 122b, the gap t1 between the electrode assembly 124 and the main body 122 can be larger than the gap t2 between the electrode assembly 124 and the main body 122 in the portion adjacent to the uniform thickness region 122a. Therefore, in the thickness reduction region 122b, a space S2 without the electrode assembly 124 is formed between the main body 122 and the electrode assembly 124. Due to this space S2, the surface pressure PS1 applied to the electrode assembly 124 in the thickness reduction region 122b is less than the surface pressure PS2 applied to the electrode assembly 124 in the uniform thickness region 122a. Therefore, the surface pressure PS1 in the thickness reduction region 122b of the cell 120 may be less uniform than the surface pressure in the uniform thickness region 122a. Compared to other locations, the distance between the electrode plates EP in the portion with lower surface pressure or applied pressure is larger, thus increasing the resistance between the electrode plates EP as the electrolyte decreases. When the resistance between the electrode plates EP increases, lithium plating, a phenomenon that drastically reduces the lifespan of cell 120, may occur.

[0158] Embodiments of this disclosure provide a pressurizing component in the portion opposite to the thickness reduction region 122b. Figure 5a The pressurizing component 130 can increase the surface pressure or applied pressure to the electrode assembly 124 in the thickness reduction region 122b. Furthermore, the pressurizing component 130 can reduce the size of the space S2 generated in the thickness reduction region 122b, thereby reducing the resistance between the electrode plates EP and mitigating or delaying lithium plating in the electrode assembly (positive plate) in the thickness reduction region 122b. Therefore, based on this embodiment, the problem of a sharp decrease in the lifespan of the cell 120 can be addressed.

[0159] Figure 9a It is shown Figures 5a to 5c A perspective view of a variant of the outer casing 151 and the pressurizing component 130 shown. Figure 9b It is shown Figure 9a A perspective view of the outer casing 151 in a separated state, as shown. Figure 9c It is along Figure 9a A cross-sectional view taken from line III-III'. Figure 9c The state of the battery cell assembly 110 before being pressurized by the pressurizing component 130 is shown in order to clearly show the part where the pressurizing component 130 pressurizes the battery cell assembly 110.

[0160] Reference Figures 9a to 9cThe side plate 153 can be provided as part of the module housing 150. The module housing 150 can include a housing body 151, which can include: a first side plate 154; a second side plate 155; and a bottom plate 152 connecting the first side plate 154 and the second side plate 155.

[0161] The outer casing 151 may include: a base plate 152 that supports the lower part of the battery cell assembly 110; and a side plate 153 that extends from both ends of the base plate 152 along a third direction Z and supports the side of the battery cell assembly 110.

[0162] and Figures 5a to 5c Compared to the outer casing 151 shown, Figures 9a to 9c The difference in the shown housing body 151 is that the pressure member 130 is integrally formed with the side plate 153. Furthermore, Figures 9a to 9c The difference in the shown outer casing 151 is that the outer casing 151 can have a segmented structure. Figures 5a to 5c The description of the housing body 151 and the pressurizing component 130 shown can also be applied to... Figures 9a to 9c .

[0163] The side plate 153 may include a first side plate 154 and a second side plate 155 respectively disposed on both sides of the cell assembly 110. The first side plate 154 may cover one side of the cell assembly 110 in the first direction X, and the second side plate 155 may cover the other side of the cell assembly 110 in the first direction X.

[0164] The pressurizing component 130 can be disposed on the inner side of the side plate 153, and can pressurize the cell assembly 110 at the portion adjacent to the electrode lead 126. The side plate 153 may include a first side plate 154 and a second side plate 155 respectively disposed on both sides of the cell assembly 110, and the pressurizing component 130 may be disposed on the first side plate 154 and the second side plate 155 respectively.

[0165] The pressurizing component 130 can be integrally formed with the side plate 153.

[0166] For example, the side plate 153 may include: a first portion A1, which is opposite to the uniform thickness region 122a of the main body 122 in the first direction X; a second portion A2, which is opposite to the thickness reduction region 122b of the main body 122 in the first direction X; and a pressure member 130 may be provided as the second portion A2 of the side plate 153. The side plate 153 may further include: a third portion A3, which is disposed outside the second portion A2 in the second direction Y.

[0167] The pressurizing member 130 may be provided as a protrusion formed on the inner side of the side plate 153. The second portion A2 of the side plate 153 may have a shape that protrudes further into the cell assembly 110 than the first portion A1. The pressurizing member 130 may be configured to form the protrusion of the second portion A2 of the side plate 153.

[0168] The pressure member 130 can be provided as an inclined surface or a curved surface formed on the inner side of the side plate 153. For example, as Figures 9a to 9c As shown, the pressurizing member 130 can be provided as a second portion A2 including an inclined surface. Alternatively, the pressurizing member 130 can also be provided as a second portion A2 including a curved surface (see reference). Figure 10a ).

[0169] The pressurizing member 130 may have a shape in which the outer side of the pressurizing member 130 protrudes further into the cell assembly 110 than the inner side in the second direction Y, where the electrode lead 126 extends from the electrode assembly 124. Since the electrode assembly 124 is thinner near the electrode lead 126 in the thickness reduction region 122b of the main body 122, the pressurizing member 130 may have a shape in which the outer side near the electrode lead 126 protrudes further into the cell assembly 110 than the inner side away from the electrode lead 126. For example, the inclined surface or curved surface constituting the second portion A2 may have a shape in which the outer side of the electrode lead 126 protrudes further away from the first portion A1 in the first direction X.

[0170] The housing body 151 can be manufactured in at least two parts, and the at least two parts can be coupled to each other in a second direction Y from which the electrode lead 126 extends from the electrode assembly 124. The housing body 151 may include: a first body 151a, including a first portion A1; a second body 151b, connected to one side of the first body 151a and including a second portion A2; and a third body 151c, connected to the other side of the first body 151a and including a second portion A2. The first body 151a, the second body 151b, and the third body 151c can be manufactured in at least two parts.

[0171] The first side plate 154 may include: a central portion 154a forming a first part A1; a pressure portion 154b forming a second part A2; and an outer portion 154c forming a third part A3. Similarly, the second side plate 155 may include: a central portion 155a forming a first part A1; a pressure portion 155b forming a second part A2; and an outer portion 155c forming a third part A3.

[0172] The side plate 153 may include: a first portion A1, which is opposite to the uniform thickness region 122a of the main body 122 in the first direction X; and a second portion A2, which is opposite to the thickness reduction region 122b of the main body 122 in the first direction X. At least two components may be separated by the boundary between the first portion A1 and the second portion A2. For example, the first side plate 154 may be separated by the boundary between the center portion 154a and the pressure portion 154b, and the second side plate 155 may also be separated by the boundary between the center portion 155a and the pressure portion 155b.

[0173] The first body 151a, the second body 151b, and the third body 151c can be manufactured by dividing them into at least two parts and then combining them. For example, the second body 151b can be manufactured separately from the first body 151a and the third body 151c. Alternatively, the first body 151a, the second body 151b, and the third body 151c can also be manufactured by dividing them into three parts and then combining them.

[0174] When the cell assembly 110 is provided in the first body 151a, the cell assembly 110 can move along... Figure 9b The arrow direction is inserted into the inner side of the first body 151a. With the cell assembly 110 positioned inside the first body 151a, the second body 151b can be inserted along... Figure 9b The arrow moves in the direction to compress the thickness reduction region 122b of the cell assembly 110 via the second body 151b. In some embodiments, during the process of attaching the second body 151b to the first body 151a, the thickness of the cell assembly 110 corresponding to the thickness reduction region 122b can be easily compressed to a thickness corresponding to the thickness of the pressure member 130. Therefore, when the housing body 151 is manufactured in at least two parts and then the at least two parts are joined together, the cell assembly 110 can be easily assembled to the housing body 151.

[0175] Figure 10a and Figure 10b It is shown Figure 9c Cross-sectional view of the variant example shown. Figure 10a and Figure 10b The state of the battery cell assembly 110 before being pressurized by the pressurizing component 130 is shown in order to clearly show the part where the pressurizing component 130 pressurizes the battery cell assembly 110.

[0176] and Figures 9a to 9c compared to, Figure 10a The difference is that the pressure part 154b of the first side plate 154 and the pressure part 155b of the second side plate 155 form a curved surface, and the pressure part 154b of the first side plate 154 and the pressure part 155b of the second side plate 155 constitute the pressure component 130.

[0177] and Figures 9a to 9c compared to, Figure 10b The difference lies in the fact that the outer surface of the side plate 153 is generally flat. The thickness of the side plate 153 of the second part A2 and the third part A3 can be greater than the thickness of the side plate 153 of the first part A1.

[0178] Aside from the differences, Figures 5a to 5c and Figures 9a to 9c The description of the housing body 151 and the pressurizing component 130 shown also applies to Figure 10a and Figure 10b .

[0179] Figure 11 This is an exploded perspective view of battery module 100a based on another embodiment. Figure 12 It is along Figure 11 A cross-sectional view taken from the IV-IV' line. Figure 12 The state of the battery cell assembly 110 before being pressurized by the pressurizing component 130 is shown in order to clearly show the part where the pressurizing component 130 pressurizes the battery cell assembly 110.

[0180] Figure 11 and Figure 12 The battery module 100a shown may include: a cell assembly 110, in which a plurality of cells 120 are arranged along a first direction X; a side plate 153, which covers both sides of the cell assembly 110 in the first direction X; and a pressurizing member 130, disposed on the inner side of the side plate 153, and pressurizing the cell assembly 110 in the portion adjacent to the electrode leads 126. The battery module 100a may include a busbar assembly 140, which includes: a busbar 145 connected to the electrode leads 126 of the cells 120; and a support plate 141 supporting the busbar 145.

[0181] and Figures 1 to 5c Compared to the battery module 100 shown, Figure 11 and Figure 12 The difference in the battery module 100a shown lies in the structure of the housing body 151. In some embodiments, Figure 11 and Figure 12 The side plate 153 in the housing body 151 of the battery module 100a shown may include a first side plate 154 and a second side plate 155 respectively disposed on both sides of the cell assembly 110, and the first side plate 154 and the second side plate 155 may have a separable structure. In some embodiments, with Figures 1 to 5c Compared to the battery module 100 shown, Figure 11 and Figure 12 The first side plate 154 and the second side plate 155 shown are not connected through the base plate (see reference). Figure 2152) Interconnected structures.

[0182] The first side plate 154 and the second side plate 155 can be fixed to the busbar assembly 140, etc., while covering both sides of the cell assembly 110. The fastening structure that keeps the side plate 153 covering both sides of the cell assembly 110 can be modified in various ways.

[0183] The pressurizing component 130 may be disposed in at least a portion of the second part A2 of the side plate 153. The pressurizing component 130 may be coupled to the side plate 153.

[0184] The pressurizing component 130 may have a constant thickness in a second direction Y extending from the electrode assembly 124 along the electrode lead 126.

[0185] right Figures 1 to 8 The explanation in (b) can also be applied to Figure 11 and Figure 12 Battery module 100a.

[0186] Figure 13 and Figure 14 They are shown respectively Figure 12 A cross-sectional view of a variant example. Figure 13 and Figure 14 The state of the battery cell assembly 110 before it is pressurized by the pressurizing component 130 is shown in order to clearly show the part where the pressurizing component 130 pressurizes the battery cell assembly 110.

[0187] and Figure 12 Compared to the pressurized component 130, Figure 13 and Figure 14 The difference in the pressure member 130 shown is that it is integrally formed with the side plate 153. The pressure member 130 may be provided as a protrusion formed on the inner side of the side plate 153.

[0188] Figure 13 The pressure member 130 shown can be provided as an inclined surface formed on the inner side of the side plate 153, but it can also be provided as a curved surface. The pressure member 130 can have a shape in which the outer side of the pressure member 130 protrudes more into the cell assembly 110 than the inner side in a second direction Y in which the electrode lead 126 extends.

[0189] The side plate 153 may include: a first portion A1, which is opposite to the uniform thickness region 122a of the main body portion 122 in the first direction X; and a second portion A2, which is opposite to the thickness reduction region 122b of the main body portion 122 in the first direction X. The first side plate 154 may include: a central portion 154a, forming the first portion A1; and a pressure portion 154b, forming the second portion A2. The second side plate 155 may include: a central portion 155a, forming the first portion A1; and a pressure portion 155b, forming the second portion A2.

[0190] The pressurizing component 130 can be provided as the second part A2 of the side plate 153. The pressurizing component 130 can correspond to the pressurizing portion 154b of the first side plate 154 and the pressurizing portion 155b of the second side plate 155.

[0191] Figure 14 The pressure member 130 shown can be integrally formed with the side plate 153 and can be provided as a protrusion formed on the inner side surface of the side plate 153. The pressure member 130 can have a constant thickness in the second direction Y in which the electrode lead 126 extends.

[0192] Aside from the differences, Figures 5a to 5c , Figures 9a to 12 The description of the housing body 151 and the pressurizing component 130 shown can also be applied to... Figure 13 and Figure 14 .

[0193] Figure 15a and Figure 15b This is a schematic diagram of a battery cell according to another embodiment. Figure 15a and Figure 15b This is a schematic diagram showing the cell 120a with electrode leads 126 disposed on one side of the bag 121.

[0194] Figure 15a The battery cell 120a shown and Figure 15b The battery cells 120b shown each have an electrode lead 126 disposed on one side of the pouch 121 or the main body 122. In some embodiments, the positive electrode lead 126a and the negative electrode lead 126b may be disposed on one side of the pouch 121, respectively. In this case, the thickness reduction region 122b is formed adjacent to the portion where the electrode lead 126 is disposed, and the uniform thickness region 122a may be formed at a position away from the electrode lead 126, for example, at a position away from the thickness reduction region 122b.

[0195] Including Figure 15a or Figure 15b In the embodiment of the battery cell 120a shown, the electrode lead 126 has a shape extending from one side of the electrode assembly 124 along the second direction Y, the thickness reduction region 122b is located on one side of the main body 122 in the second direction Y, and the pressure member ( Figure 5a The 130) can be provided on one side of the side plate 153 in the second direction Y, so as to be opposite to the thickness reduction region 122b located on one side of the main body 122 in the second direction Y.

[0196] For example, when Figure 5a The side plate 153 shown is provided in Figure 15a or Figure 15bWhen the battery cell 120a shown is used, a pressure-applying component 130 can be provided on the first side plate 154 and the second side plate 155 respectively, so as to be opposite to the thickness reduction region 122b.

[0197] exist Figure 15a and Figure 15b In the battery cell 120a shown, a pressure member 130 is also provided on the side plate 153 to face the thickness reduction region 122b adjacent to the electrode lead 126, thereby increasing the surface pressure or pressure applied to the electrode assembly 124 in the thickness reduction region 122b, and improving the problem of the sharp reduction in the service life of the battery cell 120a by alleviating or delaying the lithium plating phenomenon that occurs in the electrode assembly in the thickness reduction region 122b.

[0198] Figure 16 This is an exploded perspective view of the battery pack 200 based on the embodiment.

[0199] Reference Figure 16 The battery pack 200 may include: a plurality of battery modules 100; and a battery pack housing 210 for accommodating the plurality of battery modules 100. Figures 1 to 15b The description of battery module 100 also applies to Figure 16 Battery module 100.

[0200] The battery pack housing 210 can accommodate components such as the battery module 100 disposed within the battery pack 200. The battery pack housing 210 may include a housing body 211 supporting the battery module 100 and a battery pack cover 215 covering the housing body 211. The housing body 211 may include a bottom component 212 and side walls 213. The battery pack housing 210 may include a partition 214 spanning the space where the battery module 100 is disposed. For example, the accommodating space of the battery pack housing 210 may be divided into multiple spaces by the partition 214. The partition 214 may be arranged spanning the accommodating space to enhance the strength of the battery pack housing 210.

[0201] The battery pack 200 may include a battery control unit 220 for controlling the battery module 100. The battery control unit 220 may be disposed within the battery pack housing 210. The battery control unit 220 may include a battery management system (BMS). The configuration of the battery control unit 220 is known in various forms, and therefore detailed description is omitted. In one embodiment, the battery control unit 220 may be referred to as a processor.

[0202] Only specific examples of implementations of particular embodiments have been described. Variations, improvements, and enhancements can be made to the disclosed embodiments and other embodiments based on the disclosure of this patent document.

Claims

1. A battery module, comprising: A battery cell assembly includes a plurality of battery cells, each battery cell including a body portion configured to house an electrode assembly and an electrode lead electrically connected to the electrode assembly, the plurality of battery cells being arranged relative to each other along a first direction; Side plate, extending to be disposed on at least one side of the cell assembly in the first direction; as well as A pressure-applying component is disposed on the inner side of the side plate and configured to apply pressure to the portion of the cell assembly adjacent to the electrode leads.

2. The battery module according to claim 1, wherein, The main body includes: a region of uniform thickness at or near the center of the main body; and a region of reduced thickness closer to the electrode lead than the region of uniform thickness. The side panel includes: a first portion opposite to the uniform thickness region in the first direction; and a second portion opposite to the thickness-reducing region in the first direction. The pressurizing component is disposed in at least a portion of the second part, but not in at least a portion of the first part.

3. The battery module according to claim 2, wherein, The pressurizing component is not located in the first part.

4. The battery module according to claim 2, wherein, The side plate includes a first side plate and a second side plate respectively disposed on two opposite sides of the battery cell assembly. The distance between the first side plate and the second side plate at the center of the side plate is called the first distance, and the minimum distance between the pressure member provided on the first side plate and the pressure member provided on the second side plate is called the second distance. The first distance is greater than the second distance.

5. The battery module according to claim 4, wherein, The difference between the average thickness of the electrode assembly in the uniform thickness region and the minimum thickness of the electrode assembly in the thickness reduction region is called the maximum thickness deviation. The first distance and the second distance satisfy the following range: L1 - (dTm × N) ≤ L2 ≤ L1 - dTm L1 is the first distance, L2 is the second distance, dTm is the maximum thickness deviation, and N is the number of cells included in the cell assembly.

6. The battery module according to any one of claims 1 to 5, wherein, The pressurizing component is attached to the side plate.

7. The battery module according to any one of claims 1 to 5, wherein, The pressurizing component is integrally formed with the side plate.

8. The battery module according to claim 7, wherein, The pressurizing component is formed as a protrusion on the inner side surface of the side plate.

9. The battery module according to claim 7, wherein, The pressurizing component is formed as an inclined surface or curved surface on the inner side of the side plate.

10. The battery module according to claim 7, wherein, The side plate includes: The first portion is opposite to the uniform thickness region of the main body in the first direction; and The second part is opposite to the thickness reduction region of the main body in the first direction. The pressurizing component is formed as the second part of the side plate.

11. The battery module according to any one of claims 1 to 5, wherein, The pressurizing component has a constant thickness in a second direction in which the electrode lead extends from the electrode assembly.

12. The battery module according to any one of claims 1 to 5, wherein, The pressurizing member has a shape such that, in a second direction in which the electrode lead extends from the electrode assembly, the outer side of the pressurizing member protrudes further into the cell assembly than the inner side of the pressurizing member.

13. The battery module according to any one of claims 1 to 5, wherein, The side plate includes a first side plate and a second side plate respectively disposed on two opposite sides of the battery cell assembly. The pressurizing components are respectively disposed on the first side plate and the second side plate.

14. The battery module according to claim 13, wherein, The side panels form part of the module's outer shell. The module housing includes a housing body, which comprises: a first side plate; a second side plate; and a bottom plate connecting the first side plate and the second side plate. The housing body is manufactured in sections of at least two parts, and the at least two parts of the housing body are joined together in a second direction in which the electrode leads extend from the electrode assembly.

15. The battery module according to claim 14, wherein, The side plate includes: The first portion is opposite to the uniform thickness region of the main body in the first direction; and The second part is opposite to the thickness reduction region of the main body in the first direction and is connected to the first part. The at least two components are separated at the boundary between the first part and the second part.

16. The battery module according to any one of claims 2 to 5, wherein, The electrode leads extend from each of the two opposite sides of the electrode assembly along a second direction. The thickness reduction region is located on each of two opposite sides of the main body along the second direction. The pressurizing component is disposed on the side plate opposite each of the thickness reduction regions.

17. The battery module according to any one of claims 2 to 5, wherein, The electrode leads extend from one side of the electrode assembly along a second direction. The thickness reduction region is located on one side of the main body along the second direction. The pressurizing component is disposed on one side of the side plate along the second direction, opposite to the thickness reduction region located on one side of the main body along the second direction.

18. A battery pack, comprising: Multiple battery modules; as well as The battery pack housing is configured to accommodate the plurality of battery modules. At least one of the plurality of battery modules includes: A battery cell assembly includes a plurality of battery cells, each battery cell including a body portion configured to house an electrode assembly and an electrode lead electrically connected to the electrode assembly, the plurality of battery cells being arranged relative to each other along a first direction; Side plate, extending to be disposed on at least one side of the cell assembly in the first direction; and A pressure-applying component is disposed on the inner side of the side plate and configured to apply pressure to the portion of the cell assembly adjacent to the electrode leads.

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