Battery cell comprising support part

Abstract

According to one embodiment of the present disclosure, a battery cell may comprise: a case which accommodates an electrode assembly in an internal accommodation space and is formed with an opening; at least one part of the cover plate is inserted into the accommodating space through the opening and is combined with the shell; and a support portion provided in the accommodation space to support a lower surface of the cover plate, a side surface of the cover plate facing an inner surface of the housing being spaced apart from the inner surface of the housing by a predetermined distance to form a fixed space, at least a portion of the support portion may be disposed at a lower portion of the fixed space to form a lower surface of the fixed space.

Description

Technical Field

[0001] The present disclosure relates to a battery cell including a support portion. Background Art

[0002] Unlike primary batteries, secondary batteries are conveniently chargeable and dischargeable, and therefore are attracting attention as a power source for various mobile devices and electric vehicles.

[0003] A secondary battery can include a battery cell, in which an electrode assembly formed by stacking or rolling a positive electrode plate, a negative electrode plate, and a separator is housed inside a casing along with an electrolyte. Multiple battery cells can be stacked in a predetermined direction and housed in a battery module or battery pack.

[0004] In some types of secondary batteries, an electrode assembly may be introduced into the interior of a case of a battery cell together with an electrolyte. In a state where the electrode assembly and the electrolyte are housed, a cover may be coupled to an opening portion of the case to seal the interior space of the case.

[0005] At this time, the height of the battery cell may be increased by the thickness of the cover itself or the thickness of the welding bead itself that fixes the cover and the case to each other.

[0006] The above description is provided to help understand the technical background of the present disclosure and should not be interpreted as narrowing, limiting or restricting the technical ideas of the present disclosure. In addition, the content recorded or implied in the above description does not necessarily mean that it is prior art, and some may include content that is not prior art. Summary of the Invention

[0007] (1) Technical issues to be resolved

[0008] According to one aspect of the present disclosure, a battery cell can be provided that can reduce the volume by the thickness of a cover plate.

[0009] According to one aspect of the present disclosure, a battery cell can be provided in which welding beads do not protrude outside a case.

[0010] (2) Technical solution

[0011] According to one embodiment of the present disclosure, a battery cell may include: a shell, which accommodates an electrode assembly in an internal accommodating space and is formed with an opening; a cover plate, at least a portion of which is inserted into the accommodating space through the opening and combined with the shell; and a support portion, which is arranged in the accommodating space to support the lower surface of the cover plate, and the side surface of the cover plate facing the inner surface of the shell may be separated from the inner surface of the shell by a predetermined distance to form a fixed space, and the support portion may be arranged below the cover plate so that at least a portion of the support portion forms the lower surface of the fixed space.

[0012] According to one embodiment, a welding portion may be further included, at least a portion of which may be disposed in the fixing space to fix the housing and the cover plate to each other, and the supporting portion may be configured to support the welding portion and the cover plate together.

[0013] According to one embodiment, the support portion may be coupled to an inner surface of the housing, and at least one support portion may be provided on the inner surface of the housing to support an edge of the cover plate.

[0014] According to one embodiment, the inner surface of the housing may be provided with four or more surfaces, and the support portion may be provided on two or four surfaces facing each other on the inner surface of the housing to support the cover plate.

[0015] According to one embodiment, the support portion may be formed in such a manner as to extend along an inner surface of the housing to surround the opening of the housing.

[0016] According to one embodiment, a chamfer may be formed on the side surface of the cover plate, and the chamfer is inclined in a shape in which the length gradually increases toward the accommodation space.

[0017] According to one embodiment, the side surface of the cover plate may be stepped.

[0018] According to one embodiment, the side surface of the cover plate may include: a first side surface, separated from the inner surface of the shell; a second side surface, arranged above the first side surface, and having a length less than the length of the first side surface; and a stepped surface, connecting the first side surface and the second side surface to each other, and a chamfer may be formed on at least one of the first side surface and the second side surface of the cover plate, and the chamfer is inclined in a shape in which the length gradually increases toward the accommodating space.

[0019] According to one embodiment, an upper portion of the welding portion may be flush with an upper surface of the housing or may be disposed below the upper surface of the housing.

[0020] According to one embodiment, the upper surface of the shell can be flush with the upper surface of the cover plate or can be arranged above the upper surface of the cover plate, and the upper part of the welding part can be flush with the upper surface of the cover plate or can be arranged above the upper surface of the cover plate.

[0021] According to one embodiment, an upper portion of the welding portion may be disposed between an upper surface of the housing and an upper surface of the cover plate.

[0022] According to one embodiment, the fixed space may be formed by an inner surface of the housing, a side surface of the cover plate, and an upper surface of the support portion.

[0023] According to one embodiment, a distance between an upper surface of the support portion and an upper surface of the housing may be set to be greater than or equal to a height of the welding portion.

[0024] According to one embodiment, the length of the cover plate may be smaller than the length between the inner surfaces of the housing.

[0025] In addition, a battery cell according to another embodiment of the present disclosure may include: a shell, which accommodates an electrode assembly in an internal accommodating space; a cover plate, at least a portion of which is inserted into the accommodating space and combined with the shell; a support portion, which is arranged in the accommodating space to support the lower surface of the cover plate; a welding portion, which is arranged between the inner surface of the shell and the side surface of the cover plate facing the inner surface of the shell to fix the inner surface of the shell and the side surface of the cover plate to each other, and the support portion can be arranged to be at least partially in contact with the lower surface of the welding portion.

[0026] The technical solutions according to the present disclosure are described above, but this is merely exemplary, and it should be understood that even if other configurations not mentioned are added, they also belong to the present disclosure.

[0027] (3) Beneficial effects

[0028] The battery cell according to one embodiment of the present disclosure can reduce the volume by an amount equivalent to the thickness of the cover plate.

[0029] In the battery cell according to one embodiment of the present disclosure, the welding beads do not protrude outside the case. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a three-dimensional diagram of a battery cell according to an embodiment of the present disclosure.

[0031] Figures 2a to 2c This is a schematic diagram of the shell and cover of the battery cell.

[0032] Figure 3 It is along Figure 1 Schematic internal cross-sectional view taken along line II'.

[0033] Figure 4 yes Figure 3 A magnified view of center.

[0034] Figure 5 is a diagram illustrating one embodiment of the present disclosure.

[0035] Figure 6 is a diagram illustrating another embodiment of the present disclosure.

[0036] Figure 7 It is a diagram showing still another embodiment of the present disclosure.

[0037] Figures 8a to 8cThis is a diagram showing an embodiment in which the side surface of the cover plate adopts a stepped structure.

[0038] Description of reference numerals:

[0039] 10: Battery cell 110: Shell

[0040] 120: Electrode assembly 130: Cover plate

[0041] 200: Support

[0042] W: welding part V: fixed space

[0043] O: Opening S: Accommodation space DETAILED DESCRIPTION

[0044] Before describing the embodiments in detail, it should be noted that the terms or words used in the following description and claims should not be interpreted as limited to the general meaning or dictionary meaning, but should be interpreted as meanings and concepts that are consistent with the technical ideas of the present invention based on the principle that the inventor can appropriately define the concept of the term in order to describe his own invention in the best way.

[0045] The same reference numerals or symbols in the drawings represent components or assemblies that perform substantially the same functions. For ease of explanation and understanding, the same reference numerals or symbols will be used in different embodiments for explanation.

[0046] In the following description, unless the context clearly indicates otherwise, singular expressions include plural expressions. Terms such as "comprising" or "consisting of" should be understood as specifying the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in this specification, and do not preclude the presence or additional possibility of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0047] In addition, in the following description, expressions such as upper side, upper part, lower side, lower part, side, front part, and rear part are expressed based on the directions shown in the accompanying drawings. It should be noted that if the direction of the corresponding object changes, it can be expressed in different ways.

[0048] In the following description and claims, terms including ordinal numbers, such as "first" and "second," may be used to distinguish components. These ordinal numbers are used to distinguish identical or similar components and should not be construed as limiting the meaning of the terms. For example, the order in which components are used or arranged, as associated with these ordinal numbers, should not be construed as limiting. These ordinal numbers can be used interchangeably, if necessary.

[0049] Hereinafter, the present disclosure will be described with reference to the accompanying drawings.

[0050] Figure 1 is a three-dimensional diagram of a battery cell according to an embodiment of the present disclosure, Figures 2a to 2c This is a schematic diagram of the shell and cover of the disassembled battery cell. Figure 3 It is along Figure 1 Schematic internal cross-sectional view taken along line II'.

[0051] Also refer to Figures 1 to 3 According to one embodiment of the present disclosure, a battery cell 10 includes: a shell 110, an internal accommodation space S of which an electrode assembly 120 is accommodated and an opening O is formed; a cover plate 130, at least a portion of which is inserted into the accommodation space S through the opening O and combined with the shell 110; and a support portion 200, which is arranged in the accommodation space S to support the lower surface 130b of the cover plate 130, and a side surface 130a of the cover plate 130 facing the inner surface 110a of the shell 110 is separated from the inner surface 110a of the shell 110 by a predetermined distance a to form a fixed space V, and the support portion 200 can be arranged below the cover plate 130 so that at least a portion of the support portion 200 can form the lower surface of the fixed space V.

[0052] In other words, the battery cell 10 of the present disclosure includes: a case 110 having an opening O formed on at least one side thereof for accommodating an electrode assembly 120 in an internal accommodation space S; and a cover plate 130 , at least a portion of which is accommodated in the accommodation space of the case 110 through the opening O of the case 110 and is coupled to the case 110 , thereby closing the opening O. Furthermore, the present disclosure may include a support portion 200 , which is disposed in the accommodation space S of the case 110 and supports the cover plate 130 .

[0053] On the other hand, the fixed space V may refer to a space formed by the inner surface 110 a of the housing 110 , the side surface 130 a of the cover plate 130 , and the upper surface 200 a of the support portion 200 .

[0054] The housing 110 may provide an internal space that can accommodate the electrode assembly 120, etc., which will be described later. In the drawings, the housing 110 is shown as a substantially rectangular parallelepiped shape, but this is only an example, and the shape of the housing 110 may be changed to various shapes as long as it has a structure that forms the accommodation space S for accommodating the electrode assembly 120.

[0055] In addition, a cover plate 130 to be described later may be coupled to the opening O of the housing 110 to seal the accommodation space S. A detailed structure in which the cover plate 130 is coupled to the opening O in a state of being supported by the support portion 200 will be described later.

[0056] The material of the housing 110 may be appropriately selected based on thermal conductivity, electrical conductivity, rigidity corresponding to swelling of the electrode assembly 120 , processability, manufacturing cost, etc. For example, the housing 110 may be made of a metal material including aluminum, aluminum alloy, etc.

[0057] The electrode assembly 120 may be disposed in the accommodation space S of the case 110 .

[0058] The electrode assembly 120 may include a positive electrode material 121. The positive electrode material 121 may include a positive electrode collector and a positive electrode active material. In some embodiments, the positive electrode collector may include aluminum, an aluminum alloy, etc., and the positive electrode active material may include lithium cobalt oxide, lithium manganese oxide, lithium nickel oxide, lithium iron phosphate, etc. The positive electrode active material may be coated on the surface of the positive electrode collector. A portion of the positive electrode collector that is not coated with the positive electrode active material may be used as a positive electrode tab 120a. In some embodiments, a plurality of positive electrode tabs 120a may be provided, and some or all of the plurality of positive electrode tabs 120a may be joined to each other.

[0059] The electrode assembly 120 may include a negative electrode material 122. The negative electrode material 122 may include a negative electrode collector and a negative electrode active material. In some embodiments, the negative electrode collector may include copper, a copper alloy, nickel, a nickel alloy, etc., and the negative electrode active material may include carbon, silicon, etc. The negative electrode active material may be coated on the surface of the negative electrode collector. A portion of the negative electrode collector that is not coated with the negative electrode active material may serve as a negative electrode tab 120b. In some embodiments, a plurality of negative electrode tabs 120b may be provided, and some or all of the plurality of negative electrode tabs 120b may be joined to each other.

[0060] The electrode assembly 120 may include a separator 123. The separator 123 may be disposed between the positive electrode material 121 and the negative electrode material 122. The function of the separator 123 is to limit the physical contact between the positive electrode material 121 and the negative electrode material 122 and to provide a channel for ion movement. For example, the separator 123 may include a porous polymer film or a porous non-woven fabric. In some embodiments, the separator 123 may be made of a polymer material including polyethylene, polypropylene, etc. In addition, the separator 123 may include a dry separator and a wet separator. In some embodiments, the separator 123 may include a coating, and the coating may include a ceramic coating, etc.

[0061] The electrode assembly 120 can be formed by arranging the above-mentioned components in a winding, stacking, or other manner. As an example, the electrode assembly 120 can be formed in a structure in which the positive electrode material 121, the negative electrode material 122, and the separator 123 are wound about a longitudinal axis or a transverse axis. Alternatively, the electrode assembly 120 can be formed in a structure in which the wound structure is extruded in a direction substantially perpendicular to the winding axis. This wound structure may be referred to in the art as a "jelly roll," for example.

[0062] As another example, the electrode assembly 120 may be formed in a structure in which the positive electrode material 121, the negative electrode material 122, and the separator 123 are stacked in sequence in the vertical direction (e.g., in the thickness direction or height direction of the electrode assembly). In some cases, in the stacked structure, the separator 123 may be formed in a stacked structure in which a plurality of unit separators 123 continuous in the length direction are folded in sequence in the stacking order of the positive electrode material 121 and the negative electrode material 122. The stacked structure may be referred to in the art as "stack and folding," "z-folding," or the like. However, in this embodiment, the arrangement of the components of the electrode assembly 120 is not particularly limited. The electrode assembly 120 may have a variety of arrangements other than the above examples.

[0063] In some embodiments, the electrode assembly 120 may be composed of a plurality of unit cells. As an example, the electrode assembly 120 may include a unit cell wound in a jelly roll manner, with two or more of the unit cells combined to form the electrode assembly 120. In this embodiment, the electrode assembly 120 is composed of two jelly roll units. As another example, the electrode assembly 120 may include a unit cell wound in a stacked and folded manner, with two or more of the unit cells combined to form the electrode assembly 120.

[0064] The electrode assembly 120 can be housed in the housing space S of the housing 110 along with an electrolyte. In some embodiments, the electrolyte can be formed from an organic solvent containing a lithium salt. As an example, the lithium salt can include liquid or gel-like lithium hexafluorophosphate (LiPF6) or lithium tetrafluoroborate (LiBF4). The organic solvent can include cyclic carbonates such as ethylene carbonate (EC) and propylene carbonate (PC), and linear carbonates such as diethyl carbonate (DEC), dimethyl carbonate (DMC), and ethyl methyl carbonate (EMC).

[0065] In some other embodiments, the electrolyte can be omitted or replaced. As an example, if an inorganic solid electrolyte is used, the liquid or gel electrolyte can be omitted.

[0066] In addition, the structure of the electrode assembly 120 shown in this disclosure is exemplary. Although the present disclosure illustrates an electrode assembly 120 including a positive electrode tab 120a and a negative electrode tab 120b arranged side by side on one side of the electrode assembly 120, the position and / or number of the positive electrode tab 120a and the negative electrode tab 120b are exemplary. For example, in an embodiment not shown, the positive electrode tab 120a and the negative electrode tab 120b may be arranged such that the electrode assembly 120 (e.g., the positive electrode material 121, the negative electrode material 122, and the separator 123) are positioned between the positive electrode tab 120a and the negative electrode tab 120b. At least a portion of the positive electrode tab 120a and the negative electrode tab 120b may each be positioned between the housing 110 and the electrode assembly 120.

[0067] The cover plate 130 may be coupled to the case 110 to seal the opening of the case 110. In the drawings, the cover plate 130 is illustrated as a quadrilateral plate shape corresponding to the opening of the case 110. The cover plate 130 may be coupled to the case 110 to seal the accommodation space S of the case 110 in which the electrode assembly 120 is disposed. In some embodiments, the cover plate 130 may be welded to the case 110 by ultrasonic welding, laser welding, or the like.

[0068] The length of the cover plate 130 may be shorter than the length between the inner surfaces 110a of the housing 110. Thus, the cover plate 130 may be inserted into the opening O more easily.

[0069] The cover plate 130 may be provided with terminals 131a and 131b that are electrically connected to the electrode assembly 120. The battery cell 10 may be electrically connected to an external power source via the terminals 131a and 131b. The terminals 131a and 131b may include a positive terminal 131a and a negative terminal 131b. The positive terminal 131a may be electrically connected to the positive electrode tab 120a of the electrode assembly 120, and the negative terminal 131b may be electrically connected to the negative electrode tab 120b of the electrode assembly 120.

[0070] The cover plate 130 may include a vent 133. In this embodiment, the vent 133 is located between the positive terminal 131a and the negative terminal 131b. However, the location of the vent 133 can be varied as needed and is not necessarily limited to the illustrated example. In other embodiments, the vent 133 may be provided on or attached to the housing 110. The vent 133 may be configured to open in response to internal pressure within the housing 110. The vent 133 functions to discharge this internal pressure to the exterior of the housing 110, thereby helping to stabilize the internal components of the housing 110. In this embodiment, the vent 133 may include a notch (not shown) of a predetermined shape. The notch may be a fragile portion that is at least partially recessed in the thickness direction of the vent 133. Under the influence of internal pressure within the accommodation space S, the notch causes the vent 133 to rupture, thereby opening the accommodation space S of the housing 110 and allowing fluid (gas, etc.) to be discharged to the exterior.

[0071] On the other hand, although the present disclosure shows a secondary battery including a housing 110 having a single opening O and a cap plate 130 located on one side of the housing 110, this is merely exemplary. In an embodiment not shown, a secondary battery may be provided in which the opening O is formed on both sides of the housing 110 and the secondary battery includes a plurality of cap plates 130 respectively disposed in the openings O. For example, the secondary battery may include a first cap plate disposed on one side of the housing 110 and a second cap plate disposed on the other side of the housing 110.

[0072] The support portion 200 of the present disclosure may be disposed near the opening O in the accommodation space S. The support portion 200 may support the lower surface of the edge of the cover plate 130 that is at least partially inserted into the accommodation space S. That is, the support portion 200 is coupled to the inner surface 110 a of the housing 110 , and at least one support portion 200 may be disposed on the inner surface 110 a of the housing 110 to support the edge of the cover plate 130 .

[0073] For example, Figure 2a and Figure 2b As shown, the support portion 200 may be provided at two or four corners facing each other in the accommodation space S to support the corner portion of the edge of the cover plate 130. That is, the support portion 200 may be provided at two or four corners facing each other on the inner surface of the housing 110 to support the cover plate 200.

[0074] In addition, the support portion 200 may be provided to support the four corners of the cover plate 130. Alternatively, the support portion 200 may be provided at two of the four corners to support the cover plate 130. In other words, the support portion 200 may be provided on two or four edge surfaces of the inner surface 110a of the housing 110 facing each other to support the cover plate 130.

[0075] In other words, refer to Figure 2a and Figure 2b In one embodiment of the present disclosure, the inner surface 110a of the housing 110 is provided with four or more surfaces (four surfaces are shown in the figure), and the support portions 200 may be provided in an even number and disposed on an even number of the inner surface surfaces of the housing 110. Here, in order to support the cover plate 130, the support portions 200 may be disposed on the inner surfaces 110a facing each other.

[0076] That is, according to one embodiment of the present disclosure, the inner surface 110 a of the housing 110 is formed of four or more surfaces, and the support parts 200 may be provided on two or four surfaces to face each other in the inner surface 110 a of the housing 110 . Figure 2a It shows that the support portion 200 is arranged on four surfaces, Figure 2b FIG. 2 shows that the support portion 200 is provided on two surfaces. Figure 2a and Figure 2b As shown, the support portion 200 may be arranged along the inner surface 110a of the housing 110 (see Figure 4 ) is formed in a manner surrounding the cover plate 130 to support the entire edge of the cover plate 130. In other words, the support portion 200 can be formed in a manner extending along the inner surface 110a of the housing 110 to surround the opening O of the housing 110. Thus, the support portion 200 can support the entire edge of the cover plate 130.

[0077] As described above, the support portion 200 of the present disclosure is not limited thereto, and any support portion 200 may be provided as long as it can support the welding portion W (see FIG. Figure 5 ) and the structure of the cover 130 will not be subject to special restrictions.

[0078] Hereinafter, the coupling structure of the housing 110 and the cover 130 through the support portion 200 in the present disclosure will be described in detail.

[0079] Figure 4 yes Figure 3 A magnified view of Figure 5 is a diagram illustrating one embodiment of the present disclosure. Figure 4 and Figure 5 It is an enlarged view of the connection structure between the cover plate 130 and the housing 110 .

[0080] Also refer to Figure 4 and Figure 5 The battery cell 10 according to one embodiment of the present disclosure may include a support portion 200 disposed in the accommodation space S to support at least a portion of the cap plate 130 inserted into the accommodation space S.

[0081] More specifically, according to one embodiment, the cover plate 130 can be at least partially accommodated in the accommodation space S through the opening O of the housing 110. Here, "at least partially accommodated" means that at least a portion of the lower surface 130b of the cover plate 130 (for example, an edge portion of the cover plate 130) is disposed below the upper surface 110c of the housing 110 (in the -Z axis direction).

[0082] In one embodiment, a fixed space V may be formed between the inner surface 110a of the housing 110 and the side surface 130a of the cover plate 130. The fixed space V is a space between the inner surface 110a of the housing 110 and the side surface 130a of the cover plate 130, and may be a portion forming a welding portion W to be described later.

[0083] As an example, the side surface 130a of the cover plate 130 facing the inner surface 110a forming the storage space S of the housing 110 can be separated by a predetermined distance a from the inner surface 110a of the housing 110 to form a fixed space V. Furthermore, by separating the cover plate 130 from the housing 110 as described above, stress concentration on the edge of the cover plate 130 (the portion having the side surface 130a) can be prevented or minimized. As an example, the side surface 130a of the cover plate 130 can be tilted to form a chamfer, such that the fixed space V widens upward (in the +Z-axis direction). In other words, the side surface 130a of the cover plate 130 can be chamfered, with the chamfer being inclined so that its length gradually increases toward the storage space S. That is, the side surface 130a of the cover plate 130 can be tilted so that its length gradually increases toward the storage space S.

[0084] The drawings show a structure in which chamfers are formed on the side surface 130 a of the cover plate 130 .

[0085] However, this is only one embodiment, and as long as the structure can form the fixed space V, it is also possible not to form the chamfer. More specifically, the present disclosure may include at least one of the following structures to form the fixed space V: a first structure in which the side surface 130a of the cover plate 130 is separated from the housing 110 by a predetermined distance a (refer to Figure 7 ); a second structure in which a chamfer is formed on the side surface 130a of the cover plate 130; a third structure in which the side surface 130a of the cover plate 130 is stepped (refer to Figures 8a to 8c ); or a fourth structure that simultaneously adopts the first structure and the second structure. Figure 4 and Figure 5 The fourth structure is described based on the simultaneous use of the first and second structures. As will be described later, Figure 6 An embodiment using only the second structure is shown. Figure 7 An embodiment adopting the first structure is shown. Figures 8a to 8cAn embodiment adopting the third structure is shown.

[0086] As described above, the present disclosure is not particularly limited as long as a fixed space V is formed between the housing 110 and the cover plate 130 and a support portion 200 to be described later supports a structure of a lower surface of the fixed space V.

[0087] The support portion 200 may be coupled to the inner surface 110 a of the housing 110 and disposed in the accommodation space S. The upper surface 200 a of the support portion 200 may be disposed lower (in the −Z-axis direction) than the upper surface 110 c of the housing 110. The support portion 200 may be disposed below the cover plate 130 (in the −Z-axis direction) in the accommodation space S to support the cover plate 130.

[0088] In addition, the support portion 200 may be formed on a lower surface of the fixed space V formed between the inner surface 110 a of the housing 110 and the side surface 130 a of the cover plate 130 .

[0089] Here, “the lower surface forming the fixing space V” may refer to a lower surface provided to support a welding portion W to be described later formed in the fixing space V. That is, the support portion 200 may be provided to support not only the lower surface 130 b of the cap plate 130 , but also the lower surface of the welding portion W to be described later.

[0090] Reference Figure 5 , a welding portion W may be formed in the fixing space V. The welding portion W may fix the inner surface 110 a of the housing 110 and the side surface of the cap plate 130 a to each other.

[0091] In other words, the battery cell 10 according to an embodiment of the present disclosure may further include a welding portion W, at least a portion of which is arranged in the fixed space V to fix the housing 110 and the cover plate 130 to each other. Here, the support portion 200 may be configured to support the welding portion W and the cover plate 130 together. Here, "supporting together" means that the upper surface 200a of the support portion 200 is in contact with the lower surface of the welding portion W and the lower surface 130b of the cover plate 130 to support the welding portion W and the cover plate 130 together. That is, this may mean that the support portion 200 forming the lower surface of the fixed space V supports the lower surface of the welding portion W. In addition, "forming the lower surface of the fixed space V" may mean that the support portion 200 is configured to support the lower surface of the welding portion W.

[0092] In other words, according to one embodiment of the present disclosure, it includes: a shell 110, in which the electrode assembly 120 is accommodated in the internal accommodating space S; a cover plate 130, at least a portion of which is inserted into the accommodating space S and combined with the shell 110; a support portion 200, arranged in the accommodating space S to support the lower surface 130b of the cover plate 130; a welding portion W, arranged between the inner surface 110a of the shell 110 and the side surface 130a of the cover plate 130 facing the inner surface 110a of the shell 110 to fix them to each other, and the support portion 200 can be set to at least a portion in contact with the lower surface of the welding portion W.

[0093] On the other hand, in one embodiment, the welding portion W may be a welding bead that is configured to fix the inner surface 110a of the shell 110 and the side surface 130a of the cover plate 130 to each other. For example, the welding portion W may be formed by irradiating a laser to melt at least one of the shell 110 or the cover plate 130 near the fixed space V using a method such as laser welding. The lower surface of the welding portion W may be supported by the support portion 200. That is, the welding portion W may fix the shell 110, the cover plate 130, and the support portion 200 together. The upper portion of the welding portion W (the most protruding portion in the +Z axis direction) may be at the same height as the upper surface 110c of the shell 110 or may be disposed below the upper surface 110c of the shell 110 (in the -Z axis direction). In other words, referring to Figure 5 , a height d2 of the welding portion W may be equal to or less than a distance d1 between the support portion 200 and the housing 110 .

[0094] That is, a distance d1 between the upper surface 200 a of the support portion 200 and the upper surface 110 c of the housing 110 may be equal to or greater than a height d2 of the welding portion W.

[0095] Here, the height W of the weld portion may refer to a vertical distance from a lower surface of the weld portion W to the uppermost end of the weld portion W, or may refer to a vertical distance from an upper surface 200 a of the support portion 200 to the uppermost end of the weld portion W.

[0096] More specifically, in one embodiment, the size of the weld portion W can be increased depending on the temperature of the heat generated by laser irradiation. If at least a portion of the weld portion W is positioned above the upper surface 110c of the housing 110 (the weld portion W is positioned outside the housing), the size of the battery cell 10 may be increased. Furthermore, external impacts may be concentrated on the protruding weld portion W, making it more susceptible to impact and reducing the durability of the battery cell 10. Therefore, according to one embodiment of the present disclosure, the weld portion W may be positioned within the accommodation space S of the housing 110.

[0097] That is, the upper surface 110c of the housing 110 may be flush with or positioned above the upper surface 130c of the cover plate 130, and the upper portion of the weld portion W may be flush with or positioned below the upper surface 110c of the housing 110 (in the -Z-axis direction). Specifically, the distance d1 between the upper surface 200a of the support portion 200 and the upper surface 110c of the housing may be greater than or equal to the distance d3 between the upper surface 200a of the support portion 200 and the upper surface 130c of the cover plate. Furthermore, the distance d3 between the upper surface 200a of the support portion and the upper surface 130c of the cover plate may be less than or equal to the height d2 of the weld portion W.

[0098] The welding portion W may be configured to completely fill the fixing space V to enhance the bonding strength between the housing 110 and the cover plate 130. In one embodiment, the upper portion of the welding portion W may be flush with the upper surface 130c of the cover plate 130 or may be disposed above the upper surface 130c of the cover plate 130 (in the +Z-axis direction).

[0099] For example, the upper portion of the welding portion W may be disposed between the upper surface 110 c of the housing 110 and the cover plate 130 c .

[0100] As described above, in one embodiment, the upper portion of the welding portion W may be flush with the upper surface 110 c of the shell 110 or may be disposed below the upper surface 110 c of the shell 110 (-Z axis direction), and the upper portion of the welding portion W may be flush with the upper surface 130 c of the cover plate 130 or may be disposed above the upper surface 130 c of the cover plate 130.

[0101] On the other hand, in one embodiment, the upper surface 130c of the cover plate 130 may be flush with the upper surface 110c of the housing 110 or may be disposed below the upper surface 110c of the housing 110 (in the -Z axis direction). With the above structure, according to the present disclosure, the height of the battery cell 10 may be reduced.

[0102] On the other hand, referring to Figures 2a to 2c In one embodiment, the terminals 131a and 131b electrically connected to the external power source may be disposed on the cover plate 130, and their upper surfaces may be flush with or above the upper surface 110c of the housing 110. In other words, in one embodiment, with the height direction (Z-axis direction) as a reference, the upper surface 110c of the housing 110 may be disposed between the upper surfaces of the terminals 131a and 131b and the upper surface of the cover plate 130c.

[0103] However, the present disclosure is not limited thereto, and any structure in which the height of the battery cell 10 is reduced by inserting at least a portion of the cap plate 130 into the accommodation space S is considered to fall within the scope of the present disclosure.

[0104] Figure 6 is a diagram illustrating another embodiment of the present disclosure. Figure 6 The second structure (a structure in which chamfers are formed only on the side surface 130 a of the cover plate) is shown.

[0105] According to another embodiment, the side surface 130 c of the cap plate 130 may be chamfered to form a predetermined space (“fixed space V”) together with the inner surface 110 a of the housing 110 , and a welding portion W may be formed in the fixed space V.

[0106] In this embodiment, the lower surface of the welding portion W is supported by the side surface 130 c of the cover plate 130 , and the support portion 200 may face the welding portion W via the cover plate 130 in the height direction (Z-axis direction).

[0107] On the other hand, reference will be made to Figure 7 and Figures 8a to 8c Another embodiment of the present disclosure is described below.

[0108] Figure 7 Another embodiment of the present disclosure is shown. Figure 7 , the side surface 130 a of the cover plate 130 according to one embodiment of the present disclosure may be disposed to face in parallel with the inner surface 110 a of the housing 110 .

[0109] Figures 8a to 8c The embodiment in which the side of the cover plate adopts a stepped structure is shown. Figures 8a to 8c The side surface 130 a of the cover plate 130 may be stepped. The stepped structure may further increase the contact area between the welding portion W and the cover plate 130 .

[0110] In addition, the chamfered structure can also be adopted in this stepped structure.

[0111] More specifically, the side surface 130a of the cover plate 130 may include: a first side surface 130a-1 spaced apart from the inner surface 110a of the housing 110; a second side surface 130a-2 disposed above the first side surface 130a-1 and having a length less than that of the first side surface; and a stepped surface 130d connecting the first side surface 130a-1 and the second side surface 130a-2. A chamfer may be formed on at least one of the first side surface 130a-1 and the second side surface 130a-2 of the cover plate, the chamfer being inclined so as to gradually increase in length toward the accommodation space S.

[0112] For example, Figure 8b The structure of forming a chamfer on the first side surface 130a-1 is shown. Figure 8c The structure in which both the first side surface 130a-1 and the second side surface 130a-2 are chamfered is shown.

[0113] in addition, Figures 8a to 8c It is shown that the side surface 130a is formed into a two-step stepped structure, but the present disclosure is not limited to this. That is, as long as the side surface 130a adopts a stepped structure, even if it is formed into a three-step or more stepped structure, it will be regarded as falling within the scope of the present disclosure. Although the various embodiments of the present disclosure are described in detail above, the scope of rights of the present disclosure is not limited thereto, and it is obvious to those skilled in the art that various modifications and changes can be made without departing from the scope of the technical ideas of the present disclosure recorded in the claims. The above embodiments can be implemented by deleting certain components or by combining them with each other.

[0114] The above is merely an example of applying the principles of the present disclosure, and other configurations may be included without departing from the scope of the present disclosure.

Claims

1. A battery cell comprising: a housing that accommodates the electrode assembly in an internal accommodation space and is formed with an opening; a cover plate, at least a portion of which is inserted into the accommodation space through the opening and combined with the housing; as well as a supporting portion, disposed in the accommodation space to support the lower surface of the cover plate, The side surface of the cover plate facing the inner surface of the housing is spaced apart from the inner surface of the housing by a predetermined distance to form a fixed space. The support portion is disposed below the cover plate, so that at least a portion of the support portion forms a lower surface of the fixed space.

2. The battery cell according to claim 1, further comprising: a welding portion, at least a portion of which is disposed in the fixing space to fix the housing and the cover plate to each other, The support portion is configured to support the welding portion and the cover plate together.

3. The battery cell according to claim 1, wherein: The support portion is coupled to an inner surface of the housing, and at least one support portion is provided on the inner surface of the housing to support an edge of the cover plate.

4. The battery cell according to claim 3, wherein: The inner surface of the shell is provided with four or more surfaces. The support portions are provided on two or four surfaces facing each other among the inner surfaces of the housing to support the cover plate.

5. The battery cell according to claim 3, wherein: The support portion is formed in such a manner as to extend along an inner surface of the housing to surround the opening of the housing.

6. The battery cell according to claim 1, wherein: A chamfer is formed on the side surface of the cover plate, and the chamfer is inclined in a shape in which the length gradually increases toward the accommodation space.

7. The battery cell according to claim 2, wherein: The side surface of the cover plate is stepped.

8. The battery cell according to claim 7, wherein: The side surface of the cover plate includes: a first side surface spaced apart from the inner surface of the shell; a second side surface, disposed above the first side surface and having a length shorter than that of the first side surface; and a stepped surface connecting the first side surface and the second side surface to each other, A chamfer is formed on at least one of the first side surface and the second side surface of the cover plate, and the chamfer is inclined in a shape in which a length gradually increases toward the accommodation space.

9. The battery cell according to claim 2, wherein: The upper portion of the welding portion is flush with the upper surface of the shell or is arranged below the upper surface of the shell.

10. The battery cell according to claim 2, wherein: The upper surface of the shell is flush with the upper surface of the cover plate or is arranged above the upper surface of the cover plate, The upper portion of the welding portion is flush with the upper surface of the cover plate or is arranged above the upper surface of the cover plate.

11. The battery cell according to claim 10, wherein: The upper portion of the welding portion is disposed between the upper surface of the housing and the upper surface of the cover plate.

12. The battery cell according to claim 2, wherein: The fixed space is formed by an inner surface of the housing, a side surface of the cover plate, and an upper surface of the support portion.

13. The battery cell according to claim 2, wherein: A distance between an upper surface of the support portion and an upper surface of the housing is set to be greater than or equal to a height of the welding portion.

14. The battery cell according to claim 1, wherein: The length of the cover plate is smaller than the length between the inner surfaces of the housing.

15. A battery cell comprising: a housing for accommodating the electrode assembly in an internal accommodation space; a cover plate, at least a portion of which is inserted into the accommodation space and combined with the housing; a supporting portion, disposed in the accommodating space to support the lower surface of the cover plate; a welding portion provided between the inner surface of the housing and a side surface of the cover plate facing the inner surface of the housing to fix the inner surface of the housing and the side surface of the cover plate to each other, The support portion is provided so that at least a portion thereof contacts a lower surface of the welding portion.

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