Battery module

Abstract

Embodiments of the present invention may provide a battery module comprising: a battery assembly in which a plurality of batteries are stacked in one direction; a plurality of busbars electrically connected to electrode leads provided at both ends of the battery; and a sensing housing formed integrally with the busbars, disposed at the front and rear of the battery assembly respectively, and having a plurality of fixing grooves formed therein into which a position fixing jig used for welding the busbars and electrode leads is inserted at the top and bottom.

Description

Technology Field

[0001] The present invention relates to a battery module with improved welding quality. Background Technology

[0002] Recently, due to rising oil prices and increasing interest in the environment, the demand for eco-friendly vehicles is surging. Among these, interest in electric vehicles (EVs), which can supply and use energy utilizing various energy resources, is growing. In particular, as technology advances, research and development in EVs are focusing on achieving driving ranges comparable to those of internal combustion engine vehicles.

[0003] The driving range of an electric vehicle is directly related to the capacity and quantity of the installed battery modules. In other words, the driving range of an electric vehicle equipped with high-capacity and high-energy battery modules can be extended. Therefore, depending on the required output voltage or charge / discharge capacity, multiple batteries can be connected in series and parallel to form a battery module.

[0004] Meanwhile, the battery module may include various components such as a battery assembly formed by stacking a plurality of batteries equipped with electrode leads at both ends, a plurality of busbars electrically connected to the electrode leads, and sensing housings formed integrally with the busbars and disposed at each end of the battery assembly.

[0005] During the process of assembling components, including the battery assembly, to manufacture such battery modules, defects may occur if the relative positions of the battery assembly and other components become misaligned. In particular, if a component is missing to secure the sensing housing, which is integrally formed with the busbar, during the welding process of the busbar and electrode leads, welding defects occur, which becomes a problem that causes a degradation in the quality of the battery module. The problem to be solved

[0006] Embodiments of the present invention can provide a battery module that prevents a gap from occurring between a busbar and an electrode lead when welding a busbar and an electrode lead by preventing the sensing housing from being pushed by an external force, by forming a fixing groove into which a position fixing jig is inserted at the upper and lower portions of the sensing housing.

[0007] Embodiments of the present invention can solve the problem of welding defects caused by the gap occurring between the busbar and the electrode lead by welding the busbar and the electrode lead in close contact, thereby providing a battery module with improved quality.

[0008] Embodiments of the present invention can provide a battery module capable of delaying or preventing thermal runaway of a battery by forming a compartment through a surface pressure pad disposed between each pair of batteries.

[0009] The problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0010] Embodiments of the present invention may provide a battery module comprising a battery assembly in which a plurality of batteries are stacked in one direction, a plurality of busbars electrically connected to electrode leads provided at both ends of the battery, and a sensing housing formed integrally with the busbars and disposed at the front and rear of the battery assembly, respectively, and having a plurality of fixing grooves formed therein into which a position fixing jig used for welding the busbars and electrode leads is inserted at the top and bottom. Effects of the invention

[0011] According to embodiments of the present invention, by forming a fixing groove portion into which a position fixing jig is inserted at the upper and lower portions of the sensing housing, a battery module can be provided that prevents the sensing housing from being pushed by an external force and a gap from occurring between the bus bar and the electrode lead during welding of the bus bar and the electrode lead.

[0012] According to embodiments of the present invention, by welding the busbar and the electrode lead in close contact, the problem of welding defects caused by the gap between the busbar and the electrode lead can be resolved, thereby providing a battery module with improved quality.

[0013] According to embodiments of the present invention, a battery module capable of delaying or preventing thermal runaway of a battery can be provided by forming a compartment through a surface pressure pad disposed between each pair of batteries.

[0014] The effects of the embodiments of the present invention are not limited to those mentioned herein, and other unmentioned effects will be clearly understood by those skilled in the art from the description below. Brief explanation of the drawing

[0015] FIG. 1 is a perspective view of a battery module according to one embodiment of the present invention. Figure 2 is an exploded perspective view of Figure 1. FIG. 3 is a drawing illustrating the interior of a battery module according to one embodiment of the present invention. Figure 4 is a diagram comparing the length of the surface pressure pad of a battery module in which a fixed groove is not formed in the sensing housing and a battery module in which a fixed groove is formed in the sensing housing. FIG. 5 is a perspective view of a sensing housing according to one embodiment of the present invention. FIG. 6 is an upper side view of a sensing housing according to one embodiment of the present invention. FIG. 7 is a lower side view of a sensing housing according to one embodiment of the present invention. FIG. 8 is a cross-sectional view showing A-A' of the battery module illustrated in FIG. 1. FIG. 9 is an exploded perspective view of a sensing housing and a busbar according to one embodiment of the present invention. Figures 10a and 10b are schematic drawings illustrating the welding process of a sensing housing and a battery. Specific details for implementing the invention

[0016] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Identical or similar components regardless of drawing symbols are given the same reference number, and redundant descriptions thereof will be omitted.

[0017] The suffixes "module" and "part" for components used in the following description are assigned or used interchangeably solely for the sake of ease of drafting the specification, and do not inherently possess distinct meanings or roles. Furthermore, in describing the embodiments disclosed in this specification, detailed descriptions of related prior art are omitted if it is determined that such detailed descriptions could obscure the essence of the embodiments disclosed in this specification.

[0018] In addition, the attached drawings are intended only to facilitate understanding of the embodiments disclosed in this specification, and the technical concept disclosed in this specification is not limited by the attached drawings; it should be understood that all modifications, equivalents, and substitutions included within the concept and technical scope of the present invention are included.

[0019] Terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but said components are not limited by said terms. These terms are used solely for the purpose of distinguishing one component from another.

[0020] When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. On the other hand, when it is stated that one component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between.

[0021] A singular expression includes a plural expression unless the context clearly indicates otherwise.

[0022] In this application, terms such as “comprising” or “having” are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0023] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings.

[0024] FIG. 1 is a perspective view of a battery module according to one embodiment of the present invention, and FIG. 2 is an exploded perspective view of FIG. 1.

[0025] Referring to FIGS. 1 and 2, the battery module (100) may include a cover portion (110), a battery assembly (120), a bus bar (130), a surface pressure pad (140), and a sensing housing (150).

[0026] The cover portion (110) is intended to cover and protect the components constituting the battery module (100) and may include an end plate (111), an upper cover (112), a front cover (113), and a rear cover (114).

[0027] The end plates (111) are provided in pairs and can cover one side and the other side of the battery assembly (120), respectively. For example, the end plates (111) may be formed in the shape of rectangular plates that are elongated in the X-axis direction in the drawing and may be spaced apart in the Y-axis direction while facing each other. Here, the X-axis direction refers to the front-back direction in the drawing, the Y-axis direction refers to the left-right direction, and the Z-axis direction refers to the up-down direction.

[0028] The upper cover (112) can cover the upper part of the battery assembly (120) by connecting the upper part of the end plate (111). The front cover (113) can cover the front part of the battery assembly (120) by connecting the front end of the end plate (111), and the rear cover (114) can cover the rear part of the battery assembly (120) by connecting the rear end of the end plate (111).

[0029] The battery assembly (120) can be placed inside the cover portion (110), and a plurality of batteries (B) can be stacked in one direction. For example, two of the plurality of batteries (B) can be separated and placed as a pair within the cover portion (110).

[0030] The battery (B) constituting the battery assembly (120) may be a pouch-type battery. The pouch-type battery may include a body portion (121) having an electrode assembly in which electrodes and separators are alternately arranged inside, electrode leads (122) connected to both ends of the electrode assembly and protruding outward from the body portion (121), and a sealing portion (123) that seals the circumference of the body portion (121) and has both ends protruding in the direction in which the electrode leads (122) are formed.

[0031] The busbar (130) can be electrically connected to the electrode leads (122) provided at both ends of the battery (B). For example, the busbar (130) may be located at the front and rear of the battery assembly (120), respectively, and may be provided in multiple numbers and spaced apart in the direction in which the batteries (B) are stacked. That is, when the batteries (B) are stacked along the Y-axis direction, the multiple busbars (130) may be spaced apart along the Y-axis direction while facing the batteries (B).

[0032] Each of the multiple busbars (130) can be connected to a printed circuit board (10). For example, the printed circuit board (10) may be equipped with multiple electronic components for processing voltage information of the battery assembly (120). Thus, voltage information of the battery assembly (120) can be provided to other electronic units within the vehicle through the printed circuit board (10).

[0033] A bus bar (130) may include terminal members (131) on both sides to electrically connect a battery module (100) to another battery module (100). For example, the terminal member (131) may be formed in a shape where a portion of the upper side is bent outward and may be electrically connected to the bus bars (130) through a printed circuit board (10). Such terminal members (131) may be formed only on the front or rear of the battery module (100).

[0034] A surface pressure pad (140) may be provided between each of a pair of batteries (B), and its end may be positioned adjacent to a sensing housing (150). For example, the surface pressure pad (140) may be positioned between two adjacent batteries (B) to secure the batteries (B) and provide a constant surface pressure to ensure the batteries (B) are in close contact with each other. Additionally, a compartment may be formed to separate the pair of batteries (B) through the surface pressure pad (140).

[0035] As such, the batteries (B) can be separated by the surface pressure pad (140). If the surface pressure pad (140) is formed of a flame-retardant material, it can absorb or reflect flames to delay or prevent the thermal runaway phenomenon of the batteries (B).

[0036] The sensing housing (150) is formed integrally with the bus bar (130) and is positioned at the front and rear of the battery assembly (120), respectively, and a plurality of fixing grooves (151) may be formed at the top and bottom. Here, the fixing grooves (151) may be formed parallel to the direction in which the battery assembly (120) is stacked, and may be a space into which a position fixing jig (40, see FIG. 10) used when welding the bus bar (130) and the electrode lead (122) is inserted. For example, the fixing grooves (151) may be formed in a circular groove shape and may be positioned so as not to overlap with the electrode lead (122). That is, the fixing grooves (151) may be recessed at a height lower than the position of the electrode lead (122) at the top and bottom of the sensing housing (150).

[0037] In this way, as a fixing groove (151) into which a position fixing jig (40) is inserted is formed in the upper and lower parts of the sensing housing (150), it is possible to prevent the sensing housing (150) from being pushed backward by an external force during welding of the bus bar (130) and the electrode lead (122), thereby preventing a gap from occurring between the bus bar (130) and the electrode lead (122). Therefore, the problem of welding defects occurring between the bus bar (130) and the electrode lead (122) due to the gap can be resolved, thereby improving the quality of the battery module (100).

[0038] FIG. 3 is a drawing showing the interior of a battery module according to an embodiment of the present invention, and FIG. 4 is a drawing comparing the length of the surface pressure pad of a battery module in which a fixed groove is not formed in the sensing housing and a battery module in which a fixed groove is formed in the sensing housing.

[0039] Referring to FIGS. 3 and 4, the battery module (100) may have the end of the surface pressure pad (140) positioned between the body part (121) and the sealing part (123). In this embodiment, the length of the surface pressure pad (140) can be increased as a fixing groove part (151) into which a position fixing jig (40) is inserted is formed in the upper and lower parts of the sensing housing (150).

[0040] If a fixed groove (151) is not formed in the sensing housing (150), a certain space (S) must be left empty between the sensing housing (150) and the battery assembly (120), and a bar-shaped support member (not shown) must be inserted into this space (S) to prevent the sensing housing (150) from shifting during welding. Therefore, the surface pressure pad (140) placed between the batteries (B) could be positioned only up to the space (S) where the support member is inserted.

[0041] On the other hand, when a fixed groove (151) is formed in the sensing housing (150), a part of the position fixing jig (40) can be inserted into the fixed groove (151) to fix the position of the sensing housing (150), thereby making it possible to eliminate the space (S) for inserting the support member. Accordingly, the surface pressure pad (140) can be formed longer by the length (L) where the support member was located, so that the batteries (B) can be separated more effectively to delay or prevent thermal runaway.

[0042] In addition, since the fixed groove (151) is positioned at the upper and lower portions of the sensing housing (150), the upper and lower portions of the sensing housing (150) can be stably supported through the position fixing jig (40), thereby preventing the position fixing jig (40) from being deformed by external force applied during welding.

[0043] FIG. 5 is a perspective view of a sensing housing according to one embodiment of the present invention.

[0044] Referring to FIG. 5, the sensing housing (150) may be formed in a rectangular box shape that is elongated in the direction in which the battery (B) is stacked. For example, the sensing housing (150) may include a guide groove (152) and a slit (153) to provide a space from which the electrode lead (122) can be drawn out.

[0045] The guide groove (152) is for guiding the assembly position of the electrode lead (122) on one surface and can be formed to be long in the vertical direction. For example, the guide groove (152) can be formed so that the surface facing the body part (121) of the battery (B) is long and recessed in the vertical direction, and can be provided in multiple numbers and spaced apart in the direction in which the batteries (B) are stacked. The guide groove (152) can be formed to have a tapered shape in which the width narrows in the direction in which the electrode lead (122) is inserted.

[0046] The slit (153) may be formed in a hole shape so that it communicates with the guide groove (152) and allows the electrode lead (122) to pass through. For example, the slit (153) may be provided in multiple numbers and spaced apart in the direction in which the battery (B) is stacked.

[0047] Accordingly, when assembling the sensing housing (150) and the battery (B), the electrode lead (122) of the battery (B) is guided in position by the guide groove (152) and can be drawn out to the outside through the slit (153). The electrode lead (122) drawn out to the outside in this way can be joined to the busbar (130) by welding.

[0048] FIG. 6 is an upper side view of a sensing housing according to one embodiment of the present invention, and FIG. 7 is a lower side view of a sensing housing according to one embodiment of the present invention.

[0049] Referring to FIGS. 6 and 7, a fixed groove (151) formed in the sensing housing (150) can be positioned between guide grooves (152). For example, a portion of one side of the sensing housing (150) may be recessed to form a plurality of guide grooves (152), and a protruding member (154) may be formed between the guide grooves (152) by the guide grooves (152), and a fixed groove (151) is formed on the protruding member (154). Accordingly, the area of ​​the fixed groove (151) can be maximized to increase the contact area with the position fixing jig (40), thereby preventing the position fixing jig (40) from being deformed by external force applied during welding.

[0050] The fixed groove (151) formed on the upper part of the sensing housing (150) and the fixed groove (151) formed on the lower part of the sensing housing (150) may be formed offset from each other in the direction in which the battery (B) is stacked. In this case, the deformation of the position fixing jig (40) caused by the external force applied during welding can be reduced, thereby stably supporting the sensing housing (150), and thus preventing welding defects caused by deformation of the position fixing jig (40).

[0051] FIG. 8 is a cross-sectional view showing A-A' of the battery module illustrated in FIG. 1, and FIG. 9 is an exploded perspective view of a sensing housing and a busbar according to an embodiment of the present invention.

[0052] Referring to FIGS. 8 and 9, the bus bar (130) may be formed in the shape of a square bar with a hollow interior and may include terminal members (131) on both sides. For example, the bus bar (130) and the terminal members (131) may be installed in the sensing housing (150) by an insert molding method.

[0053] The bus bar (130) may include a first member (31) formed in the shape of a rectangular bar extending in the vertical direction, a second member (32) spaced apart from the first member (31) in one direction, a third member (33) connecting the upper end of the first member (31) and the second member (32), and a fourth member (34) connecting the lower end of the first member (31) and the second member (32).

[0054] Among the plurality of batteries (B), four batteries (B) adjacent to each other can be electrically connected to a single busbar (130). For example, electrode leads (122) provided in two of the four batteries (B) can be drawn out through the slit (153) and then bent in opposite directions to be connected to the first member (31), and electrode leads (122) provided in the remaining two batteries (B) can be drawn out through the slit (153) and then bent in opposite directions to be connected to the second member (32). That is, the electrode leads (122) provided in two of the four batteries (B) adjacent to each other can overlap each other and be connected to the busbar (130).

[0055] In this way, as two electrode leads (122) are connected in an overlapping manner on one side of the bus bar (130), the work efficiency can be increased by reducing the work required to weld between the bus bar (130) and the electrode leads (122).

[0056] FIGS. 10a and 10b are schematic diagrams illustrating the welding process of a sensing housing and a battery. Referring to FIGS. 10a and 10b, the welding process of the sensing housing and the battery is described as follows.

[0057] First, in the manufacturing process of the battery module (100), a process is required to join the busbar (130) provided in the sensing housing (150) and the electrode lead (122) provided in the battery (B) to each other. For example, the busbar (130) and the electrode lead (122) can be joined by laser welding, but in order to ensure the quality of the welding, it is necessary to weld the sensing housing (150) and the electrode lead (122) while they are in close contact with each other. Therefore, by using a pressure jig (30) to press the busbar (130) and the electrode lead (122) while the busbar (130) and the electrode lead (122) are facing each other, the sensing housing (150) and the electrode lead (122) can be brought into close contact.

[0058] However, since the bus bar (130) is formed integrally with the sensing housing (150), when the pressure jig (30) presses the bus bar (130) and the electrode lead (122) while the sensing housing (150) is not fixed in position, the sensing housing (150) moves in the direction in which the external force is applied, so proper contact between the bus bar (130) and the electrode lead (122) cannot be achieved.

[0059] Accordingly, as shown in FIG. 10a, the position of the sensing housing (150) can be fixed by inserting the fixing projection (41) of the position fixing jig (40) into the fixing groove (151) formed on the upper and lower parts of the sensing housing (150). Then, as shown in FIG. 10b, even if the bus bar (130) and the electrode lead (122) are pressed using the pressure jig (30), the sensing housing (150) is prevented from sliding, so the problem of welding defects caused by the gap between the bus bar (130) and the electrode lead (122) during welding can be solved.

[0060] The embodiments of the present invention described above are briefly explained as follows.

[0061] According to embodiments of the present invention, a battery module may be provided comprising a battery assembly in which a plurality of batteries are stacked in one direction, a plurality of busbars electrically connected to electrode leads provided at both ends of the batteries, and a sensing housing formed integrally with the busbars and disposed at the front and rear of the battery assembly, respectively, and having a plurality of fixing grooves formed therein into which a position fixing jig used for welding the electrode leads and the busbars is inserted at the top and bottom.

[0062] According to embodiments of the present invention, two of the plurality of batteries are separated and arranged to form a pair, and a surface pressure pad may be further included, each provided between the pair of batteries and having an end positioned adjacent to a sensing housing.

[0063] According to embodiments of the present invention, the battery comprises a body portion having an electrode assembly inside and a sealing portion that seals the perimeter of the body portion and has both ends protruding in the direction in which electrode leads are formed, and the end of a surface pressure pad may be disposed between the body portion and the sealing portion.

[0064] According to embodiments of the present invention, a plurality of guide grooves for guiding the assembly position of electrode leads may be formed in an upward and downward direction on one side of the sensing housing.

[0065] According to embodiments of the present invention, the sensing housing may include a plurality of slits that are in communication with a guide groove and through which an electrode lead passes.

[0066] According to embodiments of the present invention, the fixed groove portion may be disposed between the guide groove portions.

[0067] According to embodiments of the present invention, the fixed groove may be positioned so as not to overlap with the electrode lead.

[0068] According to embodiments of the present invention, a plurality of fixed grooves are inserted into a part of a position fixing jig when welding the electrode lead and the bus bar, thereby preventing the sensing housing from shifting during welding.

[0069] According to embodiments of the present invention, a fixed groove formed on the upper part of the sensing housing and a fixed groove formed on the lower part of the sensing housing may be arranged offset from each other in the direction in which the batteries are stacked.

[0070] According to embodiments of the present invention, electrode leads provided on two adjacent batteries among a plurality of batteries may overlap each other and be connected to a busbar.

[0071] It is obvious to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit and essential features of the invention.

[0072] The foregoing detailed description should not be interpreted restrictively in all respects and should be considered exemplary. The scope of the invention shall be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the invention are included within the scope of the invention. Explanation of the symbols

[0073] 100: Battery module 110: Cover part 120: Battery assembly 121: Body 122: Electrode Lead 123: Sealing part 130: Busbar 131: Terminal member 140: Face pressure pad 150: Sensing housing 151: Fixed groove 152: Guide Home 153: Slit 154: Protruding member

Claims

Claim 1 A battery module comprising: a battery assembly in which a plurality of batteries are stacked in one direction; a plurality of busbars electrically connected to electrode leads provided at both ends of the batteries; and a sensing housing formed integrally with the busbars, disposed at the front and rear of the battery assembly respectively, and having a plurality of fixing grooves formed at the top and bottom into which a position fixing jig used for welding the electrode leads and the busbars is inserted. Claim 2 A battery module according to claim 1, wherein two of the plurality of batteries are separated and arranged to form a pair, and further comprising a surface pressure pad provided between each of the pair of batteries, with the end thereof positioned adjacent to the sensing housing. Claim 3 In paragraph 2, the battery comprises a body portion having an electrode assembly inside and a sealing portion that seals the perimeter of the body portion and has both ends protruding in the direction in which the electrode leads are formed, and the end of the surface pressure pad is disposed between the body portion and the sealing portion, forming a battery module. Claim 4 A battery module according to claim 1, wherein a plurality of guide grooves for guiding the assembly position of the electrode lead are formed vertically on one side of the sensing housing. Claim 5 In paragraph 4, the battery module comprising a plurality of slits through which the electrode leads pass, wherein the sensing housing communicates with the guide groove portion. Claim 6 In paragraph 4, the fixed groove portion is a battery module disposed between the guide groove portions. Claim 7 A battery module according to claim 1, wherein the fixed groove portion is positioned so as not to overlap with the electrode lead. Claim 8 A battery module according to claim 1, wherein a portion of the position fixing jig is inserted into the plurality of fixed grooves when welding the electrode lead and the bus bar, thereby preventing the sensing housing from shifting during welding. Claim 9 A battery module according to claim 1, wherein a fixed groove formed on the upper part of the sensing housing and a fixed groove formed on the lower part of the sensing housing are arranged offset from each other in the direction in which the batteries are stacked. Claim 10 A battery module according to claim 1, wherein electrode leads provided on two adjacent batteries among the plurality of batteries overlap each other and are connected to the busbar.

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