Battery module

Abstract

The present invention relates to a battery module and, more specifically, to a battery module which can prevent leaked electrolyte from corroding internal components of the battery module when electrolyte leakage occurs in a secondary battery inside the battery module and can prevent an internal short from occurring inside the battery module, thereby ultimately improving the safety of the entire module. The battery module according to the present invention comprises: a cell assembly including a plurality of secondary batteries each having a plurality of electrode leads and arranged to be stacked in at least one direction; and a bus bar assembly including a plurality of bus bars electrically connecting the plurality of secondary batteries to each other and having one or more through-holes formed therein to allow the electrode leads to be inserted thereinto, and a bus bar frame configured to allow the plurality of bus bars to be mounted thereon, wherein in the bus bars, an immersion area that is an area immersed by electrolyte when the electrolyte leaks from the secondary batteries, is anti-corrosion treated.

Description

battery module

[0001] Cross-citation with related applications

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2023-0107254, filed August 16, 2023, the entire contents of which are incorporated herein by reference.

[0003] Technology field

[0004] The present invention relates to a battery module, and more particularly, to a battery module that can prevent leakage of electrolyte from corroding internal components of a battery module when leakage of electrolyte occurs in a secondary battery within the battery module, and can also prevent short circuits from occurring within the battery module, thereby ultimately improving the safety of the entire module.

[0005] In recent years, rising energy prices due to the depletion of fossil fuels and growing concerns about environmental pollution have made the demand for eco-friendly alternative energy sources essential for future living. Research is continuing into various power generation technologies, such as solar, wind, and tidal power. Furthermore, significant interest is being focused on power storage devices, such as batteries, to more efficiently utilize the generated electricity.

[0006] Moreover, with the technological development and increasing demand for battery-powered electronic mobile devices and electric vehicles, the demand for batteries as an energy source is rapidly increasing, and accordingly, much research is being conducted on batteries that can meet various needs.

[0007] In particular, in terms of materials, there is a high demand for lithium secondary batteries such as lithium ion batteries and lithium ion polymer batteries, which have advantages such as high energy density, discharge voltage, and output stability.

[0008] Secondary batteries can be classified into cylindrical and prismatic batteries, in which the electrode assembly is housed in a cylindrical or prismatic metal can, and pouch-type batteries, in which the electrode assembly is housed in a pouch-type case made of aluminum laminate sheet, depending on the shape of the battery case. However, the operating voltage of these unit cells, i.e., unit battery cells, is approximately 2.5 V to 4.2 V.

[0009] Therefore, when a higher output voltage is required, a secondary battery module is formed by connecting multiple individual battery cells, and the battery pack is manufactured by assembling multiple battery modules.

[0010] Fig. 1 is a perspective view illustrating a conventional battery module. Fig. 2 is a cross-sectional view taken along line A-A' of Fig. 1. Fig. 3 is a cross-sectional view taken along line B-B' of Fig. 1.

[0011] Referring to FIGS. 1 to 3, a battery module (1) composed of pouch-type secondary batteries (11) is configured such that a cell assembly (10) in which a plurality of cells manufactured as pouch-type secondary batteries (11) are stacked in a predetermined number is mounted in a rectangular parallelepiped module case (50). The module case (50) may include a top plate (51) covering the upper portion of the cell assembly (10), a side plate (52) covering the side of the cell assembly (10), and an end plate (53) coupled to the top plate (51) and the side plate (52) in the front-back direction of the module case (50).

[0012] A busbar assembly (30) may be positioned between the end plate (53) and the cell assembly (10). The busbar assembly (30) includes a busbar (31) and a busbar frame (32).

[0013] The bus bar (31) may have a shape in which a through hole (31-1) is formed in the center of a rectangular plate configuration. The secondary battery (11) has an electrode lead (12) protruding that is electrically connected to the internal electrode assembly, and this electrode lead (12) can pass through the through hole (31-1) formed in the bus bar (31) and be coupled to the bus bar (31).

[0014] The battery module (1) can have a parallel and / or series electrical connection between the secondary batteries. For this purpose, one end of the electrode lead (12) can be contact-fixed to a bus bar (31) by welding or the like for electrical connection between the respective secondary batteries (11).

[0015] And the busbar frame (32) may be a frame configuration capable of mounting a busbar (31). In order to apply multiple busbars (31), a busbar frame (32) made of an insulating material capable of mounting multiple busbars (31) may be provided.

[0016] The secondary batteries (11) that make up the cell assembly (10) contain an electrolyte. When the battery module (1) is used, this electrolyte may leak out of the secondary battery (11). This can be referred to as electrolyte leakage. If the electrolyte leaks, it may first accumulate at the bottom of the module case (50). As the amount gradually increases, the electrolyte level may gradually rise to the top of the module case (50).

[0017] Referring to FIGS. 2 and 3, the level of the leaked electrolyte is indicated by a dotted line (E). The level of the electrolyte at the time of initial leakage would have been close to the bottom surface of the module case (50), but as the amount of leakage increases, the level of the electrolyte gradually moves upward (U) and can rise to the level (E) shown in FIGS. 2 and 3.

[0018] If the electrolyte level rises significantly in this way, the bus bar (31) may become immersed in the electrolyte. Corrosion may occur in the portion of the bus bar (31) immersed in the electrolyte. In this case, a short circuit may occur between the bus bars (31) and the bus bars (31).

[0019] Figure 3 illustrates a situation where a short circuit (S) occurs below the electrolyte level (E). A short circuit may occur when a metal bridge is formed between bus bars due to a redox reaction, and a short circuit may also occur when the bus bar (31) corrodes and the corroded metal falls off. In addition, a short circuit may occur when the electrolyte itself electrically connects multiple bus bars (31) to each other.

[0020] If a short circuit occurs like this, the battery safety is greatly reduced, and serious problems such as fire or explosion may occur, which is problematic.

[0021] The present invention has been devised to solve the above problems, and the task of the present invention is to provide a battery module that can prevent leakage of electrolyte from corroding internal components of a battery module when leakage of electrolyte occurs in a secondary battery inside the battery module, can prevent short circuits from occurring inside the battery module, and ultimately improve the safety of the entire module.

[0022] A battery module according to the present invention comprises a cell assembly having a plurality of secondary batteries, each having a plurality of electrode leads, and arranged to be stacked in at least one direction, and a busbar assembly having a plurality of busbars electrically connecting the plurality of secondary batteries and having at least one through-hole formed therein for inserting the electrode leads, and a busbar frame configured to mount the plurality of busbars, wherein the busbar has an immersion area that is immersed in an electrolyte when the electrolyte leaks from the secondary battery and is subjected to a corrosion prevention treatment.

[0023] The busbar may be coated with an insulator in the immersion area.

[0024] The insulator may contain epoxy.

[0025] The insulator may be coated with a thickness of 200 to 300 um.

[0026] The insulator may be coated by at least one of dipping, air spraying, and electrostatic coating methods.

[0027] The busbar may have its immersion area deleted.

[0028] The through hole may be open at the bottom.

[0029] The busbar may have a closed-loop configuration.

[0030] The busbar may be folded with the immersion area being a residual area located above the immersion area.

[0031] The immersion zone and the residual zone may be connected in the form of a hinge joint.

[0032] The immersion region may include a hinge protrusion protruding from an end of the immersion region body portion and facing the residual region, and the residual region may include a hinge recessed portion recessed from an end of the residual region body portion and facing the immersion region.

[0033] The hinge projection includes a first projection protruding from an end of the immersion region body in a direction toward the residual region body, and a second projection protruding from a side of the first projection, and the hinge recess can be formed to correspond to the shape of the hinge projection so that the first projection and the second projection can be inserted.

[0034] The immersion region can be folded by rotating about an imaginary axis formed by extending the second protrusion.

[0035] The immersion region includes an immersion region body part and a joining protrusion protruding from an outer surface of the immersion region body part that faces the residual region, and the residual region includes a joining recessed part provided in a sunken shape from an outer surface of the residual region body part that faces the immersion region, and the joining protrusion is inserted into the joining recessed part so that the immersion region can be joined to the residual region.

[0036] The coupling protrusion may include a column portion protruding from the outer surface of the immersion area body portion and a hook portion protruding from the side of the column portion, and the coupling recess may include a catch portion that allows the hook portion to be caught when the coupling protrusion is inserted.

[0037] The residual region includes a residual region body and a connecting projection protruding from an outer surface of the residual region body that faces the immersion region, and the immersion region includes an immersion region body and a connecting recessed portion that is provided in a sunken shape from an outer surface of the immersion region body that faces the residual region, and the connecting projection is inserted into the connecting recessed portion so that the immersion region can be connected to the residual region.

[0038] The coupling protrusion may include a column portion protruding from the outer surface of the residual area body portion and a hook portion protruding from the side of the column portion, and the coupling recess may include a catch portion that catches the hook portion when the coupling protrusion is inserted.

[0039] A battery module according to the present invention comprises a cell assembly having a plurality of secondary batteries, each having a plurality of electrode leads and arranged to be stacked in at least one direction, a plurality of bus bars for electrically connecting the plurality of secondary batteries and having at least one through hole formed therein for inserting the electrode leads, and a bus bar assembly having a bus bar frame configured to mount the plurality of bus bars, wherein the bus bar has an immersion area that is a region immersed in electrolyte when electrolyte leaks from the secondary battery and is subjected to a corrosion prevention treatment, and thus, when electrolyte leaks from a secondary battery inside the battery module, the leaked electrolyte can be prevented from corroding internal components of the battery module and preventing a short circuit from occurring inside the battery module, thereby ultimately improving the safety of the entire module.

[0040] Figure 1 is a perspective view illustrating a conventional battery module.

[0041] Figure 2 is a cross-sectional view taken along line A-A' of Figure 1.

[0042] Figure 3 is a cross-sectional view taken along line B-B' of Figure 1.

[0043] Figure 4 is a perspective view illustrating a battery module according to an embodiment of the present invention.

[0044] Figure 5 is a cross-sectional view taken along line D-D' of Figure 4.

[0045] FIG. 6 is a front view showing a bus bar in a battery module according to Example 1 of the present invention.

[0046] Figure 7 is a front view showing a bus bar in a battery module according to Example 2 of the present invention.

[0047] Figure 8 is a front view showing a bus bar in a battery module according to Example 3 of the present invention.

[0048] FIG. 9 is a perspective view showing a detailed configuration of a bus bar in a battery module according to Example 3 of the present invention.

[0049] Hereinafter, with reference to the attached drawings, preferred embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the invention. However, the present invention may be implemented in various different forms and is not limited or restricted by the following examples.

[0050] In order to clearly explain the present invention, a detailed description of a part that is irrelevant to the description or a related known technology that may unnecessarily obscure the gist of the present invention has been omitted, and when adding reference signs to components of each drawing in this specification, the same or similar reference signs are attached to the same or similar components throughout the specification.

[0051] In addition, terms and words used in this specification and claims should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical idea of ​​the present invention based on the principle that the inventor can appropriately define the concept of the term to explain his or her own invention in the best way.

[0052]

[0053] Example 1

[0054] Fig. 4 is a perspective view illustrating a battery module according to an embodiment of the present invention. Fig. 5 is a cross-sectional view taken along line D-D' of Fig. 4. Fig. 6 is a front view illustrating a bus bar in a battery module according to embodiment 1 of the present invention.

[0055] Referring to FIGS. 4 and 5, a battery module (100) according to Embodiment 1 of the present invention may include a cell assembly (110) and a busbar assembly (130).

[0056] The cell assembly (110) may be an assembly including a plurality of secondary batteries (not shown). Each of the secondary batteries may be provided with a plurality of electrode leads (112), and the plurality of secondary batteries may be arranged to be stacked in at least one direction. Here, the secondary battery may be a pouch-type secondary battery. In addition, the cell assembly (110), in which a plurality of cells manufactured as pouch-type secondary batteries are stacked in a predetermined number, may be mounted in a module case (170) having a rectangular parallelepiped shape. In addition, the module case (170) may include a top plate (171) covering the upper portion of the cell assembly (110), a side plate (172) covering the side surface of the cell assembly (110), and an end plate (173) coupled to the top plate (171) and the side plate (172) in the front-back direction of the module case (170).

[0057] A busbar assembly (130) may be positioned between the end plate (173) and the cell assembly (110). The busbar assembly (130) may include a busbar (150) and a busbar frame (140).

[0058] The bus bar (150) electrically connects a plurality of secondary batteries and may be formed with at least one through hole (153) for inserting an electrode lead (112). A plurality of such bus bars (150) may be provided. Specifically, the bus bar (150) may have a shape in which a through hole (153) is formed in the center of a rectangular plate configuration. An electrode lead (112) electrically connected to an electrode assembly inside a secondary battery protrudes to the outside of the secondary battery pouch outer material, and the electrode lead (112) may pass through the through hole (153) formed in the bus bar (150) and be coupled to the bus bar (150).

[0059] The battery module (100) may have a parallel and / or series electrical connection between the secondary batteries. For this purpose, one end of the electrode lead (112) may be contact-fixed to a bus bar (150) by welding or the like for electrical connection between the respective secondary batteries.

[0060] And the busbar frame (140) may be a frame configuration capable of mounting a busbar (150). In order to apply multiple busbars (150), a busbar frame (140) made of an insulating material capable of mounting multiple busbars (150) may be provided. For example, multiple busbars (150) may be mounted on one busbar frame (140). A busbar assembly (130) including a busbar (150) and a busbar frame (140) may be provided.

[0061] Referring to FIG. 6, in the battery module (100) according to Example 1 of the present invention, the bus bar (150) may have an immersion area (151) that is an area immersed in electrolyte when electrolyte leaks from the secondary battery, which may be treated to prevent corrosion.

[0062] Specifically, the bus bar (150) may include an immersion region (151), which is a portion submerged by the electrolyte in the event of electrolyte leakage from the secondary battery, and a residual region (152) located above the immersion region (151). For example, the immersion region (151) may be a portion below a portion where an electrode lead is attached. In addition, a corrosion prevention treatment may be applied to prevent corrosion in this immersion region (151).

[0063] Referring to FIGS. 5 and 6, in the battery module (100) according to Embodiment 1 of the present invention, the bus bar (150) may be coated with an insulator (160) in the immersion region (151). By coating the bus bar (150) with the insulator (160), corrosion of the bus bar (150) can be prevented. For example, the insulator (160) may be a material containing epoxy. Accordingly, the insulating effect may be excellent.

[0064] When the immersion area (151) of the bus bar (150) is immersed in the electrolyte, corrosion may occur in the portion of the bus bar (150) immersed in the electrolyte. In this case, a short circuit may occur between the bus bars (150) and the bus bars (150).

[0065] A short circuit may occur when a metal bridge is formed between bus bars (150) due to an oxidation-reduction reaction, and when the bus bars (150) corrode, a short circuit may occur as the corroded metal falls off. In addition, the electrolyte itself may cause a short circuit by electrically connecting multiple bus bars (150) to each other. If a short circuit occurs in this way, the battery safety is significantly reduced, and serious problems such as fire or explosion may occur.

[0066] Accordingly, in the battery module (100) according to Example 1 of the present invention, by coating the immersion area (151) of the bus bar (150) with an insulator (160), it is possible to prevent leaked electrolyte from corroding internal components of the battery module (100). In addition, it is possible to prevent a short circuit from occurring within the battery module (100), and thus ultimately improve the safety of the entire module.

[0067] In the battery module (100) according to Example 1 of the present invention, the insulator (160) can be coated on the immersion area (151) by at least one of dipping, air spray, and electrostatic painting.

[0068] The dipping method may be a method of coating the immersion area (151) with an insulator (160) by immersing the bus bar (150) in an insulator (160) solution while covering the residual area (152) with a mask and leaving the immersion area (151) exposed.

[0069] The air spray method may similarly be a method of coating the insulator (160) on the immersion area (151) by spraying an insulator (160) solution onto the bus bar (150) while covering the residual area (152) with a mask and leaving the immersion area (151) exposed. The spray may be sprayed simultaneously from both sides of the bus bar (150) to coat the insulator (160), and in this case, the insulator (160) may be coated quickly and effectively.

[0070] The electrostatic coating method may be a technique of applying a powdered paint containing no solvent or thinner by electrostatic spraying, and then heating and melting it to form a film. Specifically, an anode is applied to the object to be coated, and a cathode is applied to the object to be coated, and the two are attached using electrostatic force, and then heated and melted to form a film on the insulator (160).

[0071] Meanwhile, when coating the immersion area (151), the insulator (160) may be coated with a thickness of 200 to 300 μm. If the thickness of the insulator (160) to be coated is thinner than 200 μm, the coating's holding power may be relatively weak, and if the thickness of the insulator (160) to be coated is thicker than 200 μm, the volume may increase, and the production cost, such as material cost, may unnecessarily increase.

[0072]

[0073] Example 2

[0074] Figure 7 is a front view showing a bus bar in a battery module according to Example 2 of the present invention.

[0075] Embodiment 2 of the present invention differs from Embodiment 1 in that the immersion area of ​​the bus bar is deleted to prevent corrosion.

[0076] We will explain Example 2 focusing on the differences, omitting as much of the common content as possible with Example 1. In other words, it is self-evident that if there is content not explained in Example 2, it can be supplemented through the content of Example 1.

[0077] Referring to FIG. 7, in the battery module according to Embodiment 2 of the present invention, the bus bar (150) may have the immersion region (151) deleted. The deletion of the immersion region (151) may mean that the immersion region (151) portion is cut by a cutting device or the like. Of course, it may also mean that the immersion region (151) is removed from the bus bar (150) by a method other than cutting.

[0078] Fig. 7(a) illustrates the bus bar (150) before the immersion area (151) is deleted, and Fig. 7(b) is a drawing illustrating the bus bar (150) after the immersion area (151) is deleted. Referring to Fig. 7(b), as the immersion area (151) is deleted, the through hole (153) of the bus bar (150) may be in a form in which the lower side is open. Since the immersion area (151) is deleted in this way, even if the electrolyte leaks, the bus bar (150) can be prevented from being corroded. Accordingly, the occurrence of a short circuit inside the battery module can be prevented, and thus, the safety of the entire module can be ultimately improved.

[0079] The method of deletion offers the advantage of achieving corrosion prevention more quickly and at lower production costs. Furthermore, since a portion of the busbar (150) is removed, the weight of the busbar (150) can be reduced, thereby reducing the weight of the entire battery module.

[0080] Meanwhile, referring to Fig. 7(c), after the immersion region (151) is deleted, the bus bar (150) may have a form in which the lower side of the through hole (153) is not open. That is, the bus bar (150) may have a closed-loop form. When formed in this manner, the width of the route through which the current moves is relatively widened, so advantages such as the effect of reducing resistance or increasing the current allowable capacity can be obtained.

[0081]

[0082] Example 3

[0083] Fig. 8 is a front view illustrating a bus bar in a battery module according to Embodiment 3 of the present invention. Fig. 9 is a perspective view illustrating a detailed configuration of a bus bar in a battery module according to Embodiment 3 of the present invention.

[0084] Embodiment 3 of the present invention differs from Embodiments 1 and 2 in that the immersion area of ​​the busbar is folded to prevent corrosion.

[0085] We will omit as much of the common content as possible with Examples 1 and 2 and explain Example 3 focusing on the differences. In other words, it is self-evident that if there is content not explained in Example 3, it can be supplemented through the content of Examples 1 and 2.

[0086] Referring to FIG. 8, in the battery module according to Embodiment 3 of the present invention, the bus bar (150) may have a folded immersion region (151). Specifically, the bus bar (150) may be folded such that the immersion region (151) has a residual region (152) positioned above the immersion region (151) (see arrow F).

[0087] The fact that the immersion area (151) is folded may mean that it is folded by a hinge or the like, and may also include any other form that is bent or folded.

[0088] Fig. 8(a) illustrates the bus bar (150) before the immersion region (151) is folded, and Fig. 8(b) is a drawing illustrating the bus bar (150) in a state where the immersion region (151) is folded. Referring to Fig. 8(b), as the immersion region (151) is folded, the lower immersion region (151) of the bus bar (150) can be formed such that it is no longer immersed in the electrolyte.

[0089] Since the immersion area (151) is folded in this way, even if the electrolyte leaks, the bus bar (150) can be prevented from corroding. Accordingly, the occurrence of a short circuit within the battery module can be prevented, and thus, the safety of the entire module can be ultimately improved.

[0090] When folding is used, there is an advantage in that, unlike in the case of deletion, the cross-sectional area of ​​the bus bar (150) can be maintained without reducing the effect of corrosion prevention. That is, in the case of deletion, the cross-sectional area of ​​the bus bar (150) can be reduced, which may reduce the size of the allowable current. However, in the case of the folding method, the cross-sectional area of ​​the bus bar (150) can be maintained, so the effect of corrosion prevention can be achieved without reducing the size of the allowable current.

[0091] Referring to FIG. 9, the immersion region (151) and the residual region (152) may be connected in the form of a hinge connection. To implement this hinge connection form, the present invention may include a special form.

[0092] Specifically, the immersion region (151) may include an immersion region body (151-1) and a hinge protrusion (151-2). The immersion region body (151-1) may be configured as a main body that folds upward toward the residual region (152). The immersion region body (151-1) may have a 'ㄷ' shape. The hinge protrusion (151-2) may be configured to protrude from an end of the immersion region body (151-1) facing the residual region (152).

[0093] Here, the hinge protrusion (151-2) may include a first protrusion (151-2a) and a second protrusion (151-2b). The first protrusion (151-2a) may be a portion that protrudes from the end of the immersion region body (151-1) toward the residual region (152) body (152-1). The second protrusion (151-2b) may be a portion that protrudes from the side of the first protrusion (151-2a).

[0094] The residual region (152) may include a residual region (152) body portion (152-1) and a hinge recessed portion (152-2). The residual region (152) body portion (152-1) may be a configuration of a main body that meets the folded immersion region (151). The residual region body portion (152-1) may also have a 'ㄷ' shape. However, the immersion region body portion (151-1) and the residual region body portion (152-1) may have different sizes or lengths. The hinge recessed portion (152-2) may be a recessed portion at an end of the residual region body portion (152-1) facing the immersion region (151).

[0095] Since the hinge protrusion (151-2) has a configuration of a first protrusion (151-2a) and a second protrusion (151-2b), the hinge recessed portion (152-2) can be formed to correspond to the shape of the hinge protrusion (151-2) so that the first protrusion (151-2a) and the second protrusion (151-2b) can be inserted.

[0096] With this configuration, the immersion region (151) can be folded by rotating while the hinge protrusion (151-2) is inserted into the hinge recess (152-2). Specifically, the immersion region (151) can be folded by rotating around an imaginary axis formed by extending the second protrusion (151-2b). As the immersion region (151) is folded, the immersion region (151) and the residual region (152) can be in a state of overlapping each other.

[0097] In addition, the battery module according to embodiment 3 of the present invention may further include a special structure in which the immersion region (151) can be fixed in a folded state.

[0098] Specifically, the immersion region (151) may include an immersion region body (151-1) and a coupling protrusion (151-3). The coupling protrusion (151-3) may be configured in the form of a protrusion that protrudes from an outer surface of the immersion region body (151-1) that faces the residual region (152).

[0099] Here, the coupling protrusion (151-3) may again include a column portion (151-3a) and a hook portion (151-3b). The column portion (151-3a) may have a column-shaped configuration protruding from the outer surface of the immersion region body portion (151-1), and the hook portion (151-3b) may have a configuration protruding from the side surface of the column portion (151-3a). The hook portion may have a hook-shaped configuration, and further, the end of the hook portion (151-3b) may have a triangular shape or a pointed shape.

[0100] The residual region (152) may include a residual region body portion (152-1) and a coupling recessed portion (152-3) corresponding to the immersion region (151). The coupling recessed portion (152-3) may be a recessed portion provided in a recessed shape on the outer surface of the residual region body portion (152-1) facing the immersion region (151). Accordingly, the coupling protrusion (151-3) may be inserted into the coupling recessed portion so that the immersion region (151) may be coupled to the residual region (152). Through this coupling, the immersion region (151) may be fixed to the residual region (152) in a folded state.

[0101] In addition, the coupling recessed portion (152-3) may include a catch portion (152-3a) that allows the hook portion (151-3b) to be caught when the coupling protrusion (151-3) is inserted. This may enable a more secure connection.

[0102] Also, referring to FIG. 9, a bonding protrusion (152-4) may be formed in the residual area (152), and a bonding depression (151-4) may be formed in the immersion area (151).

[0103] In addition, referring to FIG. 9, a joining protrusion (151-3) may be formed on one side of the immersion region body (151-1), a joining recessed portion (151-4) may be formed on the other side, and correspondingly, a joining recessed portion (152-3) may be formed on one side of the residual region body (152-1), and a joining protrusion (152-4) may be formed on the other side.

[0104] The specific form in which the joining protrusion (152-4) is formed in the residual region (152) may be as follows. That is, the residual region (152) may include a joining protrusion (152-4) that protrudes from an outer surface of the residual region body (152-1) that faces the immersion region (151), and the immersion region (151) may include a joining recessed portion (151-4) that is provided in a sunken shape from an outer surface of the immersion region body (151-1) that faces the residual region (152). Accordingly, the joining protrusion (152-4) may be inserted into the joining recessed portion (151-4) so ​​that the immersion region (151) may be joined to the residual region (152).

[0105] In this case, the coupling protrusion (152-4) formed in the residual area body (152-1) may include a column portion protruding from the outer surface of the residual area body (152-1) and a hook portion (not shown) protruding from the side of the column portion. In addition, the coupling recess (151-4) formed in the immersion body may include a catch portion (not shown) that allows the hook portion to be caught when the coupling protrusion (152-4) is inserted.

[0106]

[0107] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and various embodiments are possible within the scope equivalent to the technical idea of ​​the present invention and the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0108] [Explanation of symbols]

[0109] 100: Battery module

[0110] 110: Cell assembly

[0111] 130: Busbar assembly

[0112] 140: Busbar frame

[0113] 150: Busbar

[0114] 151: Immersion area

[0115] 151-1: Immersion area body

[0116] 151-2: Hinge protrusion

[0117] 151-2a: First projection

[0118] 151-2b: Second projection

[0119] 151-3: Joint protrusion

[0120] 151-3a: Column section

[0121] 151-3b: Hook section

[0122] 151-4: Joint depression

[0123] 152: Residual area

[0124] 152-1: Residual area body

[0125] 152-2: Hinge recess

[0126] 152-3: Joint depression

[0127] 152-3a: Hooked part

[0128] 152-4: Joint protrusion

[0129] 153: Penetration

[0130] 160: Insulator

[0131] 170: Module Case

[0132] 171: Top plate

[0133] 172: Side plate

[0134] 173: End Plate

Claims

1. A cell assembly having a plurality of secondary batteries, each having a plurality of electrode leads and arranged to be stacked in at least one direction; and A busbar assembly comprising a plurality of busbars electrically connecting the plurality of secondary batteries and having at least one through-hole formed therein for inserting the electrode leads, and a busbar frame configured to mount the plurality of busbars, A battery module, characterized in that the bus bar has an immersion area that is immersed in the electrolyte when the electrolyte leaks from the secondary battery, and is treated to prevent corrosion.

2. In claim 1, A battery module, characterized in that the above busbar is coated with an insulator in the above immersion region.

3. In claim 2, A battery module, characterized in that the insulator comprises epoxy.

4. In claim 2, A battery module characterized in that the above insulator is coated to a thickness of 200 to 300 um.

5. In claim 2, A battery module characterized in that the insulator is coated by at least one of dipping, air spray, and electrostatic coating methods.

6. In claim 1, A battery module characterized in that the above busbar has the above immersion region deleted.

7. In claim 6, A battery module characterized in that the upper through hole has an open lower side.

8. In claim 6, A battery module characterized in that the above busbar has a closed-loop shape.

9. In claim 1, A battery module, wherein the busbar is folded such that the immersion region has a residual region positioned above the immersion region.

10. In claim 9, A battery module characterized in that the above-mentioned immersion region and the above-mentioned residual region are connected in the form of a hinge connection.

11. In claim 10, The above immersion area is, immersion area body part; and Including a hinge projection protruding from an end of the body part of the immersion area facing the residual area, The above residual area is, Residual area body part; and A battery module characterized by including a hinge recessed portion that is recessed at an end of the residual region body portion facing the immersion region.

12. In claim 11, The above hinge projection is, It includes a first protrusion protruding in a direction toward the residual region body part from an end of the immersion region body part, and a second protrusion protruding from a side of the first protrusion, A battery module characterized in that the hinge recessed portion is formed to correspond to the shape of the hinge protrusion portion so that the first protrusion and the second protrusion can be inserted therein.

13. In claim 12, A battery module characterized in that the above-mentioned immersion region is folded by rotating around an imaginary axis formed by extending the second protrusion.

14. In claim 9 or claim 10, The above immersion area is, immersion area body part; and Including a joining protrusion protruding from the outer surface of the body part of the above immersion area facing the residual area, The above residual area is, Residual area body part; and It includes a combined recessed portion provided in a recessed shape on the outer surface of the body part of the above residual area facing the immersion area, A battery module characterized in that the above-mentioned joining protrusion is inserted into the above-mentioned joining recess so that the above-mentioned immersion region is joined to the above-mentioned residual region.

15. In claim 14, The above-mentioned joint protrusion includes a pillar portion protruding from the outer surface of the body portion of the immersion region, and a hook portion protruding from the side surface of the pillar portion, A battery module characterized in that the above-mentioned coupling recessed portion includes a catch portion that allows the hook portion to be caught in a state where the above-mentioned coupling protrusion is inserted.

16. In claim 9 or claim 10, The above residual area is, Residual area body part; and Including a joining protrusion protruding from the outer surface of the body part of the above residual area facing the immersion area, The above immersion area is, immersion area body part; and It includes a combined recessed portion provided in a recessed shape on the outer surface of the body part of the above-mentioned immersion area facing the residual area, A battery module characterized in that the above-mentioned joining protrusion is inserted into the above-mentioned joining recess so that the above-mentioned immersion region is joined to the above-mentioned residual region.

17. In claim 16, The above-mentioned joint protrusion includes a pillar portion protruding from the outer surface of the residual region body portion, and a hook portion protruding from the side surface of the pillar portion, A battery module characterized in that the above-mentioned coupling recessed portion includes a catch portion that allows the hook portion to be caught in a state where the above-mentioned coupling protrusion is inserted.

Images