Busbar and battery module comprising same

Abstract

A busbar according to one embodiment of the present invention is characterized by comprising: a first conductor layer made of a first metal and having a first side edge, a second side edge opposite to the first side edge, and a first surface extending between the first and second side edges; and a second conductor layer made of a second metal different from the first metal and laminated on and bonded to the first surface of the first conductor layer, wherein the first conductive layer has an exposed region in which the first metal is exposed on the first surface of the first conductive layer to which the second conductive layer is bonded, and the second conductive layer extends from the first side edge of the first conductive layer toward the second side edge while leaving the exposed region of the first conductive layer.

Description

Busbar and battery module including the same

[0001] The present invention relates to a busbar and a battery module including the same, and more particularly, to a busbar formed by joining dissimilar metals and a battery module including the same.

[0002] Secondary batteries, unlike primary batteries that cannot be recharged, are batteries that can be charged and discharged. They are used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are driven by electrical power sources.

[0003] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, i.e., unit battery cells, is approximately 2.5 V to 4.6 V. Therefore, when a higher output voltage is required, multiple battery cells are connected in series to form a battery pack. Furthermore, depending on the charge / discharge capacity required for the battery pack, multiple battery cells are connected in parallel to form a battery pack. Therefore, the number of battery cells included in the battery pack can be set in various ways depending on the required output voltage or charge / discharge capacity.

[0004] When configuring a battery pack by connecting multiple battery cells in series or parallel, it is common to first configure a battery module comprising at least one battery cell, preferably multiple battery cells, and then use at least one such battery module and add other components to configure the battery pack. Here, the battery module refers to a component in which multiple battery cells are connected in series or parallel, and the battery pack may refer to a component in which multiple battery modules are connected in series or parallel to increase capacity and output.

[0005] A battery module is composed of multiple cells electrically connected using a busbar, and the electrode leads of the battery cells are connected to the busbar.

[0006] However, when the electrode lead of the battery cell is connected to the bus bar, the electrode lead, which is made of a metal of a different material from the bus bar, may be joined to the bus bar, which may increase the occurrence rate of cracks along with corrosion at the welding surface and reduce weldability.

[0007] The present invention is intended to solve the problems described above, and aims to provide a busbar with improved weldability and a battery module including the same.

[0008] According to one embodiment of the present invention, a busbar comprises: a first conductor layer having a first side edge, a second side edge opposite the first side edge, and a first surface extending between the first and second side edges, the first conductor layer being made of a first metal; and a second conductor layer being made of a second metal different from the first metal and laminated and bonded to the first surface of the first conductor layer; wherein the first conductor layer has an exposed area where the first metal is exposed on the first surface of the first conductor layer to which the second conductor layer is bonded, and the second conductor layer leaves the exposed area of ​​the first conductor layer and extends from the first side edge of the first conductor layer toward the second side edge.

[0009] Additionally, the second conductor layer extends from the first side edge to the second side edge.

[0010] Additionally, the exposure area of ​​the first conductor layer extends from the second side edge toward the first side edge.

[0011] Additionally, the first metal or the second metal includes aluminum.

[0012] Additionally, the first metal or the second metal includes copper.

[0013] Additionally, the first conductor layer has a through hole.

[0014] Additionally, the through hole is disposed between the exposed area and the second conductor layer.

[0015] In addition, the second conductor layer includes a first portion; a second portion extending from one end of the first portion in the direction of the second side edge of the first conductor layer; and a third portion extending from the other end of the first portion in the direction of the second side edge of the first conductor layer.

[0016] Additionally, the first portion of the second conductor layer is arranged parallel to the exposed area of ​​the first conductor layer.

[0017] Additionally, the first conductor layer has a through hole, and the through hole is disposed between a first portion of the second conductor layer and an exposed area of ​​the first conductor layer.

[0018] According to one embodiment of the present invention, a battery module comprises: a battery cell stack in which a plurality of battery cells are stacked; a module case for accommodating the battery cell stack; and a bus bar for electrically connecting the battery cells; wherein the bus bar comprises: a first conductive layer having a first side edge, a second side edge opposite the first side edge, and a first surface extending between the first and second side edges, the first conductive layer being made of a first metal; and a second conductive layer made of a second metal different from the first metal, the second conductive layer being laminated and bonded to the first surface of the first conductive layer, wherein the first conductive layer has an exposed area where the first metal is exposed on the first surface of the first conductive layer to which the second conductive layer is bonded, and the second conductive layer leaves the exposed area of ​​the first conductive layer and extends from the first side edge of the first conductive layer toward the second side edge.

[0019] Additionally, an electrode lead of the battery cell made of the first metal is bonded to the exposed area of ​​the first conductor layer, and an electrode lead of the battery cell made of the second metal is bonded to the second conductor layer.

[0020] In addition, the battery module further includes a terminal bus bar made of the first metal, and an electrode lead of the battery cell made of the first metal is coupled to the terminal bus bar.

[0021] In addition, the battery module further includes a terminal bus bar made of the second metal, and an electrode lead of the battery cell made of the second metal is coupled to the terminal bus bar.

[0022] In addition, the battery module further includes a busbar frame arranged on one side of the battery cell stack, and the busbar is arranged on the busbar frame.

[0023] The busbar and battery module according to one embodiment of the present invention have the effect of improving weldability by having the electrode lead and the busbar be welded to the same type.

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

[0025] Figure 2 is an exploded perspective view of a battery module according to one embodiment of the present invention.

[0026] Figure 3 is a perspective view of a battery cell in one embodiment of the present invention.

[0027] Figure 4 is a perspective view of a terminal bus bar in one embodiment of the present invention.

[0028] FIG. 5 is a perspective view of an insulating cover and an end plate in one embodiment of the present invention.

[0029] Figure 6 is a detailed view of a busbar frame in one embodiment of the present invention.

[0030] FIG. 7 is a drawing showing a bus bar to which electrode leads are coupled in one embodiment of the present invention.

[0031] Figure 8 is a drawing showing a bus bar in one embodiment of the present invention.

[0032] Figure 9 is an exploded perspective view of the bus bar of Figure 8.

[0033] Fig. 10 is a cross-sectional view of line AA in Fig. 8.

[0034] Fig. 11 is a rear view of the bus bar of Fig. 8,

[0035] FIG. 12 is a drawing showing a bus bar according to another embodiment of the present invention.

[0036] Fig. 13 is a drawing showing a busbar (terminal busbar) joint plate in one embodiment of the present invention.

[0037] The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Accordingly, in some embodiments, well-known process steps, well-known device structures, and well-known techniques are not specifically described to avoid ambiguity in the interpretation of the present invention. Like reference numerals refer to like elements throughout the specification.

[0038] In order to clearly represent multiple layers and regions in the drawings, the thickness may be enlarged. Similar parts are designated by the same drawing reference numerals throughout the specification. When an element such as a layer, film, region, or plate is said to be "over" another element, this includes not only the case where it is "directly over" that element but also the case where there are other elements in between. Conversely, when an element is said to be "directly over" another element, this means that there are no other elements in between. Furthermore, when an element such as a layer, film, region, or plate is said to be "under" another element, this includes not only the case where it is "directly under" that element but also the case where there are other elements in between. Conversely, when an element is said to be "directly under" another element, this means that there are no other elements in between.

[0039] A busbar and battery module (1000) according to one embodiment of the present invention will be described in detail with reference to the drawings.

[0040] FIG. 1 is a perspective view of a battery module according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of a battery module according to an embodiment of the present invention, FIG. 3 is a perspective view of a battery cell according to an embodiment of the present invention, FIG. 4 is a perspective view of a terminal bus bar according to an embodiment of the present invention, FIG. 5 is a perspective view of an insulating cover and an end plate according to an embodiment of the present invention, FIG. 6 is a detailed view of a bus bar frame according to an embodiment of the present invention, FIG. 7 is a view showing a bus bar to which electrode leads are coupled according to an embodiment of the present invention, FIG. 8 is a view showing a bus bar according to an embodiment of the present invention, FIG. 9 is an exploded perspective view of the bus bar of FIG. 8, FIG. 10 is a cross-sectional view taken along line AA in FIG. 8, FIG. 11 is a rear view of the bus bar of FIG. 8, FIG. 12 is a view showing a bus bar according to another embodiment of the present invention, and FIG. 13 is a view showing a bus bar according to another embodiment of the present invention. In one embodiment, this is a drawing showing a busbar (terminal busbar) joint plate.

[0041] A battery module (1000) according to one embodiment of the present invention may include a battery cell stack (100) in which a plurality of battery cells (110) are stacked, a module case (200) that accommodates the battery cell stack (100), a bus bar frame (300) positioned on one side and / or the other side of the battery cell stack (100), an insulating cover (500) positioned on the outside of the bus bar frame (300), and an end plate (400) positioned on the outside of the insulating cover (500).

[0042] The above battery cell stack (100) may be formed by stacking a plurality of battery cells (110) along one direction, and the plurality of battery cells (110) may be electrically connected. The direction in which the plurality of battery cells (110) are stacked may be the X-axis direction (or -X-axis direction) in FIG. 2.

[0043] The direction from the front to the rear of the battery cell stack (100), or the opposite direction, may be defined as the longitudinal direction of the battery cell stack (100), and may be the Y-axis direction in the drawing. In addition, the direction from the upper surface to the lower surface of the battery cell stack (100), or the opposite direction, may be defined as the width direction of the battery cell stack (100), and may be the Z-axis direction in the drawing.

[0044] The longitudinal direction of the battery cell stack (100) may be substantially the same as the longitudinal direction of the battery cell (110). The electrode leads (111, 112) of the battery cell (110) may be positioned on the front and rear sides of the battery cell stack (100), and the bus bars (310, 320) of the battery module (1000) may be positioned close to the front and rear sides of the battery cell stack (100) to easily form an electrical connection with the electrode leads (111, 112).

[0045] The battery cell (110) may be provided as a pouch-shaped battery cell, and the number of pouch-shaped battery cells stacked per unit area may be maximized. However, the battery cell (110) does not necessarily have to be provided as a pouch-shaped battery cell, and may be provided in a square, cylindrical, or other various shapes.

[0046] A battery cell (110) provided in a pouch type may include an electrode assembly and a cell case (115) that accommodates the electrode assembly (see FIG. 3).

[0047]

[0048] The cell case (115) of the battery cell (110) may be a pouch-type cell case (115) for accommodating the electrode assembly. The cell case (115) includes a lower case and an upper case covering the lower case, and the upper and lower cases may be formed integrally. In addition, as illustrated in FIG. 3, the connecting portions of the upper and lower cases may be formed in a structure in which they are bent and folded. In addition, as illustrated, the upper case may completely cover the lower case, and a sealing portion (114) may be formed at the periphery.

[0049]

[0050] Both the upper and lower cases can be formed of a laminate structure including an inner covering layer, a metal layer, and an outer covering layer. The inner covering layer is located on the inside of the cell case (115) based on the metal layer and is in direct contact with the electrode assembly, so it must have insulation and electrolytic resistance. In addition, in order to seal it from the outside, the sealing portion where the inner layers are thermally bonded must have excellent thermal bonding strength. The metal layer is located between the inner covering layer and the outer covering layer and serves as a barrier layer that prevents moisture or various gases from penetrating into the battery from the outside. A preferable material for the metal layer in contact with the inner covering layer is an aluminum (Al) thin film that is lightweight and has excellent formability. The outer covering layer is located on the outside of the cell case (115) based on the metal layer, and this outer covering layer can use a heat-resistant polymer with excellent tensile strength, moisture permeability, and air permeability to protect the electrode assembly while ensuring heat resistance and chemical resistance. For example, nylon or polyethylene terephthalate can be used.

[0051]

[0052] A receiving groove (116) can be formed in each of the upper and lower cases, and an electrode assembly can be accommodated in the receiving groove (116) of the upper and lower cases.

[0053] The electrode assembly housed in the cell case (115) may be one of a group consisting of a jelly-roll type electrode assembly having a structure in which a separator is interposed between long sheet-shaped positive and negative electrodes and then rolled up, a stack type electrode assembly having unit cells having a structure in which rectangular positive and negative electrodes are stacked with a separator interposed between them, a stack-folding type electrode assembly in which the unit cells are rolled up by a long separator film, and a lamination-stack type electrode assembly in which the unit cells are stacked with a separator interposed between them and attached to each other.

[0054]

[0055] Additionally, the electrode assembly may include two electrode tabs and two electrode leads (111, 112) each connected to the electrode tabs by a weld.

[0056] Among the two electrode leads (111, 112), one electrode lead (111, 112) may be a positive lead connected to the positive tab, and the other electrode lead (111, 112) may be a negative lead connected to the negative tab. For example, the positive electrode lead (111) may be made of aluminum (Al), and the negative electrode lead (112) may be made of copper (Cu).

[0057] A lead film (113) may be attached to each of the electrode leads (111, 112). The lead film (113) coupled to the electrode leads (111, 112) is positioned between the electrode leads (111, 112) and the cell case (115), thereby preventing a short circuit from occurring between the electrode leads (111, 112) and the cell case (115) and improving the sealing force, thereby preventing leakage of the electrolyte, etc.

[0058]

[0059] The two electrode leads (111, 112) are shown as being arranged on each side of the electrode assembly, but may be arranged on only one side of the electrode assembly depending on the arrangement of the electrode tabs.

[0060]

[0061] The above module case (200) may be for protecting the battery cell stack (100) and electrical components connected thereto from external physical impact, and the module case (200) may accommodate the battery cell stack (100) and electrical components connected thereto in the internal space of the module case (200).

[0062] The structure of the module case (200) may vary, and for example, the structure of the module case (200) may be a mono-frame structure. Here, the mono-frame may be in the form of a metal plate having an upper surface, a lower surface, and both side surfaces that are integrated. The mono-frame may be manufactured by extrusion molding. As another example, the structure of the module case (200) may be a structure in which a U-shaped frame and an upper plate (upper surface (201)) are combined. In the case of a structure in which a U-shaped frame and an upper plate are combined, the structure of the module case (200) may be formed by combining an upper plate on the upper side of a U-shaped frame, which is a metal plate having a lower surface and both side surfaces that are combined or integrated, and each frame or plate may be manufactured by press molding. In addition, the structure of the module case (200) may be provided as an L-shaped frame structure in addition to a mono-frame or a U-shaped frame, and may be provided as various structures not described in the above-described examples.

[0063]

[0064] The structure of the module case (200) may be provided in an open form along the longitudinal direction of the battery cell stack (100). The front and rear sides of the battery cell stack (100) may not be covered by the module case (200). The electrode leads (111, 112) of the battery cells (110) may not be covered by the module case (200). The front and rear sides of the battery cell stack (100) may be covered by a bus bar frame (300), an end plate (400), or bus bars (310, 320) to be described later, and through this, the front and rear sides of the battery cell stack (100) may be protected from external physical impacts, etc.

[0065]

[0066] A compression pad (150) may be positioned between one side of the inner surface of the battery cell stack (100) and the module case (200).

[0067] The compression pad (150) can be arranged to face the battery cell (110) at the outermost end of the battery cell stack (100) in the X-axis direction in the drawing.

[0068] Also, although not shown, a thermally conductive resin may be injected between the inner surface of the battery cell stack (100) and the module case (200), and a thermally conductive resin layer (not shown) may be formed between one of the inner surfaces of the battery cell stack (100) and the module case (200) by the injected thermally conductive resin. At this time, the thermally conductive resin layer may be positioned on the Z-axis of the battery cell stack (100), and the thermally conductive resin layer may be formed between the battery cell stack (100) and the bottom surface positioned on the -Z-axis of the module case (200).

[0069] The above busbar frame (300) is positioned on one side of the battery cell stack (100), and can cover one side of the battery cell stack (100) and simultaneously guide the connection between the battery cell stack (100) and an external device. Specifically, the busbar frame (300) can be positioned on the front or rear side of the battery cell stack (100) as illustrated, and can also be positioned on the upper side, lower side, or side. At least one of a busbar (310, 320) and a module connector can be mounted on the busbar frame (300). As illustrated in FIG. 2, one side of the busbar frame (300) can be connected to one side or the other side of the battery cell stack (100), and the other side of the busbar frame (300) can be connected to the busbar (310, 320).

[0070] The busbar frame (300) may be made of an electrically insulating material or may include an insulating material. The busbar frame (300) may limit contact between the busbars (310, 320) and other parts of the battery cells (110) other than the parts where the busbars are connected to the electrode leads (111, 112), thereby preventing electrical short circuits from occurring. The busbar frame (300) may be positioned on one side and the other side of the battery cell stack (100), respectively.

[0071] FIG. 6 is a drawing illustrating a busbar frame (300) according to an embodiment of the present invention. A busbar (310, 320) may be mounted on one surface of the busbar frame (300), and the busbar (310, 320) may be for electrically connecting the battery cell stack (100) or the battery cells (110) and an external device circuit. A plurality of busbars (310, 320) may be arranged, and are positioned between the battery cell stack (100) or the busbar frame (300) and the end plate (400), thereby protecting the battery from external impacts, etc., and minimizing the deterioration of durability due to external moisture, etc.

[0072] The busbar (310, 320) can be electrically connected to the battery cell stack (100) through the electrode leads (111, 112) of the battery cell (110).

[0073] Specifically, the electrode leads (111, 112) of the battery cell (110) can be bent and connected to the bus bars (310, 320) after passing through the lead slit formed in the bus bar frame (300).

[0074] The bus bar (310) may be for electrically connecting the battery cells, and as shown in FIGS. 6 and 7, electrode leads (111, 112) of the battery cells (110) may be connected to both sides of the bus bar (310), and the electrode lead (111) connected to one side of the bus bar (310, 320) may be a positive lead, and the electrode lead (112) connected to the other side of the bus bar (310, 320) may be a negative lead.

[0075] In the present embodiment, the busbar (310) may be a clad metal busbar formed by bonding different types of metals. As a clad metal busbar, the busbar (310) may be formed by bonding a first conductor layer (311) and a second conductor layer (315), as illustrated in FIGS. 8 to 10, and may be formed by laminating a second conductor layer (315) on the first conductor layer (311). The busbar (310) may have a through hole (312). In another embodiment, the busbar (310) may not have a through hole (312). FIG. 12 is a drawing illustrating a busbar (310) without a through hole (312).

[0076] The first conductor layer (311) and the second conductor layer (315) may be laminated metal plates. The first conductor layer (311) may have an approximately rectangular shape. The first conductor layer (311) may have a first side edge (311a) and a second side edge (311b). The first side edge (311a) and the second side edge (311b) may be parallel and arranged on opposite sides.

[0077] Additionally, the first conductor layer (311) has a first side (311c), and a second conductor layer can be laminated on the first side (311c). The first side (311c) can extend between the first side edge (311a) and the second side edge (311b) and can be formed in a plane.

[0078] The first conductor layer (311) may be formed of a first metal, and the second conductor layer (315) may be formed of a second metal different from the first metal. The first metal may include aluminum (Al) or may be aluminum. The second metal may include copper (Cu) or may be copper. Alternatively, the second metal may include aluminum (Al) or may be aluminum. The first metal may include copper (Cu) or may be copper. Alternatively, the first metal or the second metal may be formed of an alloy in which aluminum or copper is combined with another metal.

[0079] The first conductive layer (311) may have a through hole (312) in the center as illustrated, and an exposed area (313) in which the first metal is exposed may be formed in an area where the second conductive layer (315) is not laminated on the first side (311c) of the first conductive layer (311). The exposed area (313) may extend from the second side edge (311b) toward the first side edge (311a). The exposed area (313) may not extend to the first side edge (311a). The exposed area (313) may extend from the second side edge (311b) to one edge of the through hole (312).

[0080] In the exposed area (313), an electrode lead (111) of a positive electrode made of a first metal (or aluminum) from a battery cell (110) can be joined, and the electrode lead (111) of the positive electrode can be electrically connected to the first conductor layer (311) by welding in the exposed area (313).

[0081] The second conductor layer (315) may be laminated on the first surface (311c) of the first conductor layer (311). The second conductor layer (315) may cover the entire first surface (311c) of the first conductor layer (311), or may cover a portion of the first surface (311c) of the first conductor layer (311). The portion of the first surface (311c) of the first conductor layer (311) covered by the second conductor layer (315) may be 50 to 80% of the first surface (311c). The exposed area (313) of the first conductor layer (311) may be 20 to 50% of the first surface (311c).

[0082] As illustrated in FIGS. 8 to 10, a second conductor layer (315) can be laminated on an area excluding the exposed area (313) on the first surface (311c) of the first conductor layer (311), and an exposed area (316) exposed to the outside from the second conductor layer (315) can be formed on an area excluding the exposed area (313).

[0083] In the present embodiment, the second conductor layer (315) may be about 30-40% of the thickness of the first conductor layer (311), or for example, about 1 / 3. Accordingly, when the second metal is heavier than the first metal, for example, when the first metal includes aluminum and the second metal includes copper, the bus bar can be reduced in weight while ensuring a minimum welding strength with the electrode lead.

[0084] The second conductor layer (315) may extend from the first side edge (311a) of the first conductor layer (311) toward the second side edge (311b) while leaving the exposed area (313) of the first conductor layer (311). The second conductor layer (315) may extend from the first side edge (311a) to the second side edge (311b).

[0085] The second conductor layer (315) may include a first portion (317), a second portion (318), and a third portion (319), and the first portion (317), the second portion (318), and the third portion (319) may be formed integrally.

[0086] The first portion (317) may be arranged parallel to the exposed area (313) of the first conductor layer (311), and a through hole (312) may be arranged between the first portion (317) and the exposed area (313). For example, a negative electrode lead (112) may be connected to the first portion (317).

[0087] The second portion (318) may extend from one end of the first portion (317) toward the second side edge (311b). The second portion (318) may extend from one end of the first portion (317) to the second side edge (311b).

[0088] The third portion (319) may extend from the other end of the first portion (317) toward the second side edge (311b). The third portion (319) may extend from the other end of the first portion (317) to the second side edge (311b).

[0089] That is, the second part (318) and the third part (319) can extend parallel from both ends of the first part (317). An exposed area (313) of the first conductor layer (311) can be arranged between the second part (318) and the third part (319).

[0090] The first portion (317), the second portion (318), and the third portion (319) can form an exposed area (316) in the second conductor layer (315).

[0091] In this embodiment, an exposed area (313) where a first conductor layer (311) is exposed and an exposed area (316) where a second conductor layer (315) is exposed can be arranged together on one surface of a bus bar (310), and a positive electrode lead (111) can be joined to the exposed area (313), and a negative electrode lead (112) can be joined to the exposed area (316).

[0092] Accordingly, an anode electrode lead (111) made of aluminum can be joined to a first conductor layer (311) made of a first metal, aluminum, and a cathode electrode lead (112) made of copper can be joined to a second conductor layer (315) made of a second metal, copper.

[0093] When an electrode lead made of a metal different from that of the bus bar is joined to the bus bar, the crack occurrence rate may increase and weldability may deteriorate. In the present embodiment, as described above, the positive electrode lead (111) is joined to a first conductor layer (311) of the same metal material as the positive electrode lead, and the negative electrode lead (112) is joined to a second conductor layer (315) of the same metal material as the negative electrode lead, thereby forming a homogeneous joint, thereby reducing the crack occurrence rate and improving weldability.

[0094] In addition, a busbar weld plate (310a) may be joined to the second portion (318) of the second conductor layer (315) (see FIG. 13). The busbar weld plate (310a) may be connected to a connector (not shown), and the connector to which the busbar weld plate (310a) is connected may be connected to a connector (350) illustrated in FIG. 6. The connector (350) may be connected to a sensing unit (sensing plate) (not shown) to perform functions such as voltage sensing of the battery cell (110).

[0095] That is, the sensing unit is connected to the bus bar (310) through the bus bar joint plate (310a) coupled to the bus bar (310) and can sense the voltage of the battery cell (110), etc.

[0096] In this embodiment, the busbar joint plate (310a) may be made of a second metal (e.g., copper). Accordingly, it can be welded to a second conductor layer (315) made of the second metal, thereby improving weldability.

[0097] Battery cells (110) constituting the battery cell stack (100) can be connected in series or parallel by bus bars (310, 320).

[0098] The busbars (310, 320) may include terminal busbars (320) for electrically connecting one battery module (100) to another battery module (100).

[0099] At least a portion of the terminal bus bar (320) may be exposed to the outside of the end plate (400) to be connected to another battery module (100), and the end plate (400) may be provided with a terminal opening (410) for this purpose.

[0100] The terminal bus bar (320) can have one end (second part (322)) exposed through the opening (510) of the insulating cover (500) and the terminal opening (410) of the end plate (400).

[0101] As illustrated in FIG. 4, the terminal bus bar (320) may include a first portion (321) connected to the electrode leads (111, 112) of the battery cell (110) and a second portion (322) exposed to the outside through a terminal opening (410). In addition, the terminal bus bar (320) may further include a bending portion (323) formed between the first portion (321) and the second portion (322).

[0102] In the terminal bus bar (320), the first part (321) can be connected to the second part (322) through the bending part (323), and one side of the first part (321) and one side of the second part (322) can be perpendicular to each other. That is, by forming a bent bending part (323) in the terminal bus bar (320), the second part (322) can protrude and be seated in the seating part (530) of the insulating cover (500), and the second part (322) can be electrically connected to the pack bus bar (not shown). A joining hole (322a) is formed in the second part (322) constituting one end of the terminal bus bar (320), and the second part (322) of the terminal bus bar (320) is fixed by a fixing pin (not shown) inserted into the joining hole (322a).

[0103] In this embodiment, two terminal bus bars (320) can be arranged on both sides of the bus bar frame (300).

[0104] Among the two terminal bus bars (320), one terminal bus bar (320) may be a positive (+) terminal bus bar (320), and the other may be a negative (-) terminal bus bar (320).

[0105] In this embodiment, the terminal bus bar (320) on the left in FIG. 6 may be a positive (+) terminal bus bar (320) and may be made of aluminum (Al).

[0106] An electrode lead (111) of a positive electrode made of a first metal can be joined to a terminal bus bar (320) on the left side made of a first metal (e.g., aluminum), and weldability can be improved by forming a joint of the same metal.

[0107] In Fig. 4, an electrode lead (111) can be welded to a first portion (321) of a terminal bus bar (320). The terminal bus bar (320) can be nickel-plated (Ni plating) and tin-plated (Sn plating).

[0108] Additionally, a terminal busbar weld plate (320a) can be joined to the bending portion (323) of the terminal busbar (320) (see Fig. 13).

[0109] The terminal busbar joint plate (320a) can be connected to a connector (not shown) like the busbar joint plate (310a), and the connector connected to the terminal busbar joint plate (320a) can be connected to the connector (350) shown in Fig. 6. The connector (350) can be connected to a sensing unit (sensing plate) (not shown) to perform functions such as voltage sensing of the battery cell (110).

[0110] That is, the sensing unit is connected to the terminal bus bar (320) through the terminal bus bar joint plate (320a) coupled to the terminal bus bar (320) and can sense the voltage of the battery cell (110), etc.

[0111] In this embodiment, the terminal busbar joint plate (320a) may be made of a first metal (e.g., aluminum). Accordingly, it can be welded to a positive terminal busbar (320) made of the first metal, thereby improving weldability.

[0112] In Fig. 6, the terminal bus bar (320) on the right may be a negative (+) terminal bus bar (320) and may be made of copper (Cu).

[0113] The negative electrode lead (112) of the second metal can be joined to the terminal bus bar (320) on the right side made of a second metal (e.g., copper), and weldability can be improved by forming a joint of the same metal.

[0114] Additionally, a terminal busbar weld plate (320b) can be joined to the terminal busbar (320) on the right.

[0115] The terminal busbar joint plate (320b) can be connected to a connector (not shown) like the busbar joint plate (310a), and the connector connected to the terminal busbar joint plate (320b) can be connected to the connector (350) shown in Fig. 6. The connector (350) can be connected to a sensing unit (sensing plate) (not shown) to perform functions such as voltage sensing of the battery cell (110).

[0116] In this embodiment, the terminal busbar joint plate (320b) may be made of a second metal (e.g., copper). Accordingly, it can be welded to the negative terminal busbar (320) made of the second metal, thereby improving weldability.

[0117] The end plate (400) may be used to protect the battery cell stack (100) and electrical components connected thereto from external physical impact by covering the open surface of the module case (200). To this end, the end plate (400) may be manufactured from a material having a predetermined strength, and for example, the end plate (400) may include a metal such as aluminum or a plastic material.

[0118] A terminal opening (410) may be formed in the end plate (400). The terminal openings (410) may be positioned on each side of the end plate (400), and a portion of the insulating cover (500) and one end (second portion (322)) of the terminal bus bar (320) may be exposed through the terminal openings (410).

[0119] In addition, a connector opening may be located between terminal openings (410) located on both sides of the end plate (400), and a module connector may be exposed to the outside through the connector opening.

[0120] The end plate (400) can be combined with the module case (200) while covering the busbar frame (300) or busbar (310, 320) located on one side of the battery cell stack (100). Each corner of the end plate (400) can be combined with a corresponding corner of the module case (200) by welding, bolting, hooking, or the like.

[0121] The end plate (400) can be positioned on one side and the other side of the module case (200) to cover both sides of the battery cell stack (100). In this embodiment, an example in which the end plate (400) is positioned on the front and rear sides of the module case (200) is shown.

[0122] The insulating cover (500) may be positioned inside the end plate (400) and outside the busbar frame (300). In addition, an insulating cover (500) for electrical insulation may be positioned between the end plate (400) and the busbar frame (300). That is, the busbar frame (300), the insulating cover (500), and the end plate (400) may be sequentially positioned outside the battery cell stack (100). Like the end plate (400), the busbar frame (300) and the insulating cover (500) may each be configured in multiples.

[0123] The insulating cover (500) may be made of or include an electrically insulating material and may block the busbar (310, 320) from contacting the end plate (400).

[0124] The insulating cover (500) may include an opening (510) and a mounting portion (530). The openings (510) may be positioned on each of the upper sides of the insulating cover (500), and one end (second portion (322)) of the terminal bus bar (320) may be exposed through the openings (510).

[0125] In addition, a connector opening may be located between the openings (510) located on both sides of the insulating cover (500), and the module connector may be exposed to the outside through the connector opening.

[0126] The insulating cover (500) may be positioned on the inner surface of the end plate (400) and may be in close contact with the inner surface of the end plate (400), but this is not necessarily the case.

[0127] As described above, one end (the second part (322)) of the terminal bus bar (320) can be exposed through the opening (510), and the exposed one end (the second part (322)) of the terminal bus bar (320) can be seated on the mounting portion (530). Accordingly, the mounting portion (530) can be positioned adjacent to the opening (510) and can be positioned on the upper outer surface.

[0128] The mounting portion (530) may have a second portion (322) of the terminal bus bar (320) mounted on its upper surface, and thus the upper surface of the mounting portion (530) may form a mounting surface. In addition, as illustrated in FIG. 5, the mounting portion (530) may include a fixing member (531) for fixing the terminal bus bar (320).

[0129] The fixing member (531) can fix the second part (322) of the terminal bus bar (320) and may include a fixing hole (531a).

[0130] A fixing pin (not shown) can be inserted into the fixing hole (531a) above. A fixing pin (not shown) inserted into a joining hole (322a) formed in a second part (322) of the terminal bus bar (320) is fixed by being coupled to the fixing hole (531a), thereby fixing the second part (322) of the terminal bus bar (320) to the insulating cover (500).

[0131] Accordingly, the second part (322) of the terminal bus bar (320) is seated on the mounting portion (530) of the insulating cover (500), and the second part (322) is seated on the fixing member (531) arranged on the mounting portion (530) and comes into contact with it.

[0132] In addition, a terminal cover portion (not shown) covering one end (second portion (322)) of the exposed terminal bus bar (320) can be placed on the insulating cover (500).

[0133] Meanwhile, electrical connection between battery modules (1000) can be made through a pack bus bar (not shown). The pack bus bar is a member for connecting one battery module (1000) to another adjacent battery module (1000) or a BDU (Battery Disconnection Unit), and can be connected to an exposed end (second part (322)) of a terminal bus bar (320). For example, the pack bus bar can be connected to overlap the upper end (second part (322)) of one end of the terminal bus bar (320).

[0134] After one end of the pack bus bar is placed overlapping the second part (322) of the terminal bus bar (320), a fixing pin is sequentially inserted into the coupling hole of the pack bus bar and the coupling hole (322a) of the second part (322) of the terminal bus bar (320), and then the fixing pin is fixed to the fixing groove (531a) of the mounting portion (530), so that the pack bus bar can be connected to the terminal bus bar (320).

[0135] And, the second part (322) of the terminal bus bar (320) can be fixed to the insulating cover (500) together with the pack bus bar by a fixed pin.

[0136] One or more battery modules (1000) according to the present invention as described above can form a battery pack. The battery pack according to the present invention can accommodate at least one battery module (1000) inside a pack case and can include various control and protection systems such as a BMS (Battery Management System) and a cooling system.

[0137] The battery module (1000) and battery pack according to the present invention, configured as described above, can be applied to various devices. Specifically, they can be applied to transportation vehicles such as electric bicycles, electric vehicles, and hybrid vehicles, or ESS (Energy Storage Systems), but are not limited thereto and can be applied to various devices capable of using secondary batteries.

[0138] Although the present invention has been described with reference to preferred embodiments as described above, it is not limited to the above embodiments, and various changes and modifications may be made by a person having ordinary skill in the art to which the invention pertains within a scope that does not depart from the spirit of the present invention.

[0139] The present invention can provide a busbar and battery module in which the electrode lead and the busbar are welded in the same manner to improve weldability.

Claims

1. A first conductor layer made of a first metal, having a first side edge, a second side edge opposite the first side edge, and a first surface extending between the first and second side edges; and A second conductor layer comprising a second metal different from the first metal and laminated and bonded to the first surface of the first conductor layer; On the first surface of the first conductor layer to which the second conductor layer is bonded, the first conductor layer has an exposed area in which the first metal is exposed, A busbar characterized in that the second conductor layer leaves an exposed area of ​​the first conductor layer and extends from the first side edge of the first conductor layer toward the second side edge.

2. In paragraph 1, The second conductor layer is a bus bar extending from the first side edge to the second side edge.

3. In paragraph 1, The exposed area of ​​the first conductor layer is a bus bar extending from the second side edge toward the first side edge.

4. In paragraph 1, A busbar wherein the first metal or the second metal comprises aluminum.

5. In paragraph 1, A bus bar wherein the first metal or the second metal comprises copper.

6. In paragraph 1, The above first conductor layer is a bus bar having a through hole.

7. In paragraph 6, The above through hole is a bus bar arranged between the exposed area and the second conductor layer.

8. In paragraph 1, The above second conductor layer Part 1; and A second portion extending from one end of the first portion toward the second side edge of the first conductor layer; and A busbar including a third portion extending from the other end of the first portion toward the second side edge of the first conductor layer.

9. In paragraph 8, A bus bar in which the first portion of the second conductor layer is arranged parallel to the exposed area of ​​the first conductor layer.

10. In paragraph 8, The above first conductor layer has a through hole, The above through hole is a bus bar arranged between the first portion of the second conductor layer and the exposed area of ​​the first conductor layer.

11. A battery cell stack in which a plurality of battery cells are stacked; A module case for accommodating the above battery cell stack; and A bus bar for electrically connecting the above battery cells is included; The above bus bar A first conductor layer comprising a first metal and having a first side edge, a second side edge opposite the first side edge, and a first surface extending between the first and second side edges; and A second conductor layer comprising a second metal different from the first metal and laminated and bonded to the first surface of the first conductor layer; On the first surface of the first conductor layer to which the second conductor layer is bonded, the first conductor layer has an exposed area in which the first metal is exposed, A battery module wherein the second conductive layer leaves an exposed area of ​​the first conductive layer and extends from the first side edge of the first conductive layer toward the second side edge.

12. In paragraph 11, The electrode lead of the battery cell made of the first metal is bonded to the exposed area of ​​the first conductor layer, A battery module in which the electrode lead of the battery cell made of the second metal is bonded to the second conductor layer.

13. In paragraph 11, A battery module wherein the second conductor layer extends from the first side edge to the second side edge.

14. In paragraph 11, A battery module wherein the exposed area of ​​the first conductor layer extends from the second side edge toward the first side edge.

15. In paragraph 11, A battery module wherein the first metal or the second metal comprises aluminum.

16. In paragraph 11, A battery module wherein the first metal or the second metal comprises copper.

17. In paragraph 11, A battery module wherein the first conductor layer has a through hole.

18. In paragraph 11, The above battery module further includes a terminal bus bar made of the first metal, A battery module in which the electrode lead of the battery cell made of the first metal is connected to the terminal bus bar.

19. In paragraph 11, The above battery module further includes a terminal bus bar made of the second metal, A battery module in which the electrode lead of the battery cell made of the second metal is connected to the terminal bus bar.

20. In paragraph 11, Further comprising a busbar frame arranged on one side of the above battery cell stack, The above busbar is a battery module arranged on the above busbar frame.

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