Battery unit having reduced temperature deviation within battery cell and cooling plate included therein

Abstract

The battery unit according to an embodiment of the present invention may comprise: a battery cell stack comprising multiple battery cells; and a cooling plate for cooling the battery cell stack, wherein the cooling plate comprises two inlets through which a refrigerant is introduced and which are formed at different positions, and an outlet through which the refrigerant is discharged; the two inlets comprise a first inlet and a second inlet; and the directions in which the refrigerant is introduced through the first inlet and the second inlet are parallel to the direction in which the multiple battery cells are stacked.

Description

Battery unit with improved temperature deviation within the battery cell and cooling plate included therein

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2025-0015053 dated February 6, 2025, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of this specification.

[0003] The present invention relates to a battery unit and a cooling plate included therein, and more specifically, to a battery unit with improved temperature variation within a battery cell and a novel cooling plate included therein.

[0004] Secondary batteries, which possess electrical characteristics such as high energy density and high applicability across product categories, are widely applied not only to portable devices but also to electric vehicles or hybrid vehicles powered by electric sources, and power storage devices. These secondary batteries are attracting attention as a new energy source for enhancing eco-friendliness and energy efficiency, not only for the primary advantage of drastically reducing the use of fossil fuels but also because they generate no by-products from energy use.

[0005] While small mobile devices use one or two or three battery cells per device, medium-to-large devices such as automobiles require high output and large capacity. Therefore, medium-to-large battery modules consisting of multiple battery cells electrically connected are used.

[0006] Meanwhile, with the recent increase in the need for large-capacity structures, including their utilization as energy storage sources, there is a growing demand for multi-module battery packs that combine multiple battery modules in which multiple secondary batteries are connected in series and / or parallel.

[0007] Meanwhile, when configuring a battery pack by connecting multiple battery cells in series or parallel, it is common practice to first construct a battery module consisting of at least one battery cell, and then use this at least one battery module to add other components to form the battery pack. Recently, a modular type battery module / pack structure is also being used, which omits the module frame constituting the battery module and directly loads a battery cell stack containing multiple battery cells onto a pack frame.

[0008] Battery units comprising such medium-to-large battery modules and / or battery packs are composed of rechargeable secondary batteries; therefore, these high-output, high-capacity secondary batteries generate a significant amount of heat during the charging and discharging process. If the heat generated by the battery modules during charging and discharging is not effectively removed, heat accumulation occurs, which consequently accelerates the degradation of the battery modules / packs and, in some cases, can lead to ignition or explosion. Accordingly, medium-to-large battery packs for vehicles or power storage devices, which contain multiple medium-to-large battery modules and are high-output, high-capacity batteries, require a cooling system to cool the battery cells embedded within them.

[0009] The cooling plates used in conventional cooling systems have one inlet and one outlet. While the portion near the inlet is cooled first, the portion near the outlet may be cooled by a refrigerant that has risen in temperature. Consequently, battery cells located near the outlet have a problem with inferior cooling performance compared to those located near the inlet.

[0010] The problem that the present invention aims to solve is to provide a battery unit with improved temperature variation within the battery cell and a cooling plate included therein.

[0011] However, the problems that the embodiments of the present invention aim to solve are not limited to the problems described above and can be expanded in various ways within the scope of the technical ideas included in the present invention.

[0012] A battery unit according to one embodiment of the present invention includes a battery cell stack comprising a plurality of battery cells and a cooling plate for cooling the battery cell stack, wherein the cooling plate includes two inlets formed at different locations into which a refrigerant is introduced and an outlet into which the refrigerant is discharged, wherein the two inlets include a first inlet and a second inlet, and the direction in which the refrigerant is introduced through the first inlet and the second inlet may be parallel to the direction in which the plurality of battery cells are stacked.

[0013] The first inlet is located adjacent to a first electrode lead protruding from the first outermost battery cell among the battery cells, and the second inlet is located adjacent to a second electrode lead protruding from the second outermost battery cell among the battery cells, and the first outermost battery cell and the second outermost battery cell may be positioned on the same side or opposite sides.

[0014] The first electrode lead and the second electrode lead may be located on different sides with respect to the longitudinal direction of the battery cell.

[0015] The direction in which the refrigerant is discharged through the above outlet may be parallel to the direction in which the plurality of battery cells are stacked.

[0016] The above cooling plate includes a first cooling section including a first cooling channel connected to the first inlet, a second cooling section including a second cooling channel connected to the second inlet, and a third cooling section including a third cooling channel connected to the outlet, wherein the first cooling section is disposed at the front end of the cooling plate, the second cooling section is disposed at the rear end of the cooling plate, and the third cooling section may be disposed at the center of the cooling plate.

[0017] The direction in which the first cooling channel extends may be perpendicular to the direction in which the first electrode lead protrudes, and the direction in which the second cooling channel extends may be perpendicular to the direction in which the second electrode lead protrudes.

[0018] The first cooling channel above may overlap vertically with a plurality of first electrode leads protruding from each of the plurality of battery cells, and the second cooling channel above may overlap vertically with a plurality of second electrode leads protruding from each of the plurality of battery cells.

[0019] When the portion including the first cooling portion, the second cooling portion, and the third cooling portion is referred to as a lower cooling plate, the cooling plate further includes an upper cooling plate including a fourth cooling portion connected to the first cooling portion, a fifth cooling portion connected to the second cooling portion, and a sixth cooling portion connected to the third cooling portion, wherein the fourth cooling portion is connected to the first cooling portion through a first connecting portion extending in the vertical direction, the fifth cooling portion is connected to the second cooling portion through a second connecting portion extending in the vertical direction, and the sixth cooling portion is connected to the third cooling portion through a third connecting portion extending in the vertical direction, and the refrigerant may flow upward at the first connecting portion and the second connecting portion, and the refrigerant may flow downward at the third connecting portion.

[0020] The lower cooling plate may have a larger surface area than the upper cooling plate.

[0021] A cooling plate according to another embodiment of the present invention includes two inlets formed at different locations into which a refrigerant is introduced, and an outlet into which the refrigerant is discharged, wherein the two inlets include a first inlet and a second inlet, and the direction in which the refrigerant is introduced through the first inlet, the direction in which the refrigerant is introduced through the second inlet, and the direction in which the refrigerant is discharged through the outlet are parallel to each other.

[0022] The above outlet can be placed between the two inlets.

[0023] The above cooling plate includes a first cooling section including a first cooling channel connected to the first inlet, a second cooling section including a second cooling channel connected to the second inlet, and a third cooling section including a third cooling channel connected to the outlet, wherein the first cooling section is disposed at the front end of the cooling plate, the second cooling section is disposed at the rear end of the cooling plate, and the third cooling section may be disposed at the center of the cooling plate.

[0024] When the portion including the first cooling portion, the second cooling portion, and the third cooling portion is referred to as a lower cooling plate, the cooling plate further includes an upper cooling plate including a fourth cooling portion connected to the first cooling portion, a fifth cooling portion connected to the second cooling portion, and a sixth cooling portion connected to the third cooling portion, wherein the fourth cooling portion is connected to the first cooling portion through a first connecting portion extending in a vertical direction, the fifth cooling portion is connected to the second cooling portion through a second connecting portion extending in a vertical direction, and the sixth cooling portion is connected to the third cooling portion through a third connecting portion extending in a vertical direction, and the refrigerant may flow upward at the first connecting portion and the second connecting portion, and the refrigerant may flow downward at the third connecting portion.

[0025] The first inlet, the second inlet, and the outlet may be formed on the same side of the cooling plate, and the first connection part, the second connection part, and the third connection part may be formed on the same other side of the cooling plate.

[0026] According to the embodiments, multiple inlets are formed to uniformly cool multiple parts that require cooling.

[0027] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art from the description in the claims.

[0028] FIG. 1 is a perspective view showing a battery unit according to one embodiment of the present invention.

[0029] Figure 2 is an exploded perspective view of the battery unit included in Figure 1.

[0030] FIG. 3 is a perspective view of a battery cell included in the battery unit of FIG. 2.

[0031] Figure 4 is a diagram showing the flow of refrigerant in the cooling plate of Figure 1.

[0032] Figure 5 is a diagram showing the arrangement relationship between the battery cell stack and the cooling plate in the battery unit of Figure 1.

[0033] Figure 6 is a diagram showing the flow of refrigerant in a cooling plate according to a comparative example.

[0034] Figure 7 is a diagram showing the arrangement relationship between the cooling plate of Figure 6 and the battery cell stack.

[0035] FIG. 8 is a perspective view showing a two-layer cooling plate structure according to another embodiment of the present invention.

[0036] Hereinafter, various embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. The present invention may be embodied in various different forms other than those described below, and the scope of the present invention is not limited by the embodiments described herein.

[0037] To clearly explain the present invention, parts unrelated to the description have been omitted, and the same reference numerals are used for identical or similar components throughout the specification.

[0038] In addition, the size and thickness of each component shown in the drawings have been arbitrarily enlarged or reduced for convenience of explanation, so it is obvious that the content of the present invention is not limited to what is illustrated. In the drawings below, the thickness of each layer has been enlarged to clearly represent various layers and regions. Also, in the drawings below, the thickness of some layers and regions has been exaggerated for convenience of explanation.

[0039] Furthermore, when describing a part such as a layer, membrane, region, or plate as being "above" or "on" another part, this should be interpreted to include not only cases where the corresponding part is "directly above" the other part, but also cases where there is another part in between. Conversely, when describing a corresponding part such as a layer, membrane, region, or plate as being "directly above" another part, it may mean that there is no other part in between. Additionally, stating that a part is "above" or "on" a reference part means being located above or below the reference part, and does not necessarily mean being located "above" or "on" in the opposite direction of gravity. Meanwhile, just as describing a part as being "above" or "on" another part can be understood by referring to the aforementioned content, describing a part as being "below" or "under" another part can also be understood.

[0040] Furthermore, throughout the specification, when a part is described as "including" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0041] Additionally, throughout the specification, "planar" means when the part is viewed from above, and "cross-sectional" means when the cross-section obtained by cutting the part vertically is viewed from the side.

[0042] FIG. 1 is a perspective view showing a battery unit according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the battery unit included in FIG. 1. FIG. 3 is a perspective view of a battery cell included in the battery unit of FIG. 2.

[0043]

[0044] Referring to FIGS. 1 to 3, a battery unit (100) according to one embodiment of the present invention comprises a battery cell stack (120) in which a plurality of battery cells (110) are stacked, each having electrode leads (111, 112) protruding in opposite directions; a module frame (200) that houses the battery cell stack (120); and a first bus bar frame (310) disposed on one side of the battery cell stack (120) in one direction (x-axis direction, -x-axis direction) in which the electrode leads (111) protrude.

[0045] First, referring to FIG. 3, the battery cell (110) may be a pouch-type battery cell. For example, the battery cell (110) according to the present embodiment may have a structure in which two electrode leads (111, 112) face each other and protrude from one end (114a) and the other end (114b) of the cell body (113). More specifically, the electrode leads (111, 112) are connected to an electrode assembly (not shown) and protrude from the electrode assembly (not shown) to the outside of the battery cell (110).

[0046] Meanwhile, the battery cell (110) can be manufactured by bonding the two ends (114a, 114b) of the cell case (114) and the one side (114c) connecting them, while the electrode assembly (not shown) is housed in the cell case (114). In other words, the battery cell (110) according to the present embodiment has a total of three sealing parts (114sa, 114sb, 114sc), and the sealing parts (114sa, 114sb, 114sc) are sealed by a method such as heat fusion, and the other side can be formed as a connecting part (115). The cell case (114) can be made of a laminate sheet including a resin layer and a metal layer.

[0047] Additionally, the connecting portion (115) may extend along one edge of the battery cell (110), and a protrusion (110p) of the battery cell (110), called a bat-ear, may be formed at the end of the connecting portion (115). Additionally, as the cell case (114) is sealed with the protruding electrode leads (111, 112) in between, a terrace portion (116) may be formed between the electrode leads (111, 112) and the cell body (113). That is, the battery cell (110) includes a terrace portion (116) that extends from the cell case (114) in the direction in which the electrode leads (111, 112) protrude.

[0048] Although the battery cell (110) according to the present embodiment has been described as being pouch-type, it is not limited thereto, and a prismatic cell or a cylindrical cell may also be used.

[0049] A plurality of battery cells (110) may be configured, and a plurality of battery cells (110) may be stacked so as to be electrically connected to each other to form a battery cell stack (120). Referring to FIG. 2, battery cells (110) may be stacked along the y-axis direction to form a battery cell stack (120). A first bus bar frame (310) may be located on one side of the battery cell stack (120) in the direction in which the electrode lead (111) protrudes (x-axis direction). Although not specifically illustrated, a second bus bar frame may be located on the other side of the battery cell stack (120) in the direction in which the electrode lead (112) protrudes (-x-axis direction). The battery cell stack (120) and the first bus bar frame (310) may be accommodated together in a module frame (200). The module frame (200) can protect the battery cell stack (120) housed inside the module frame (200) and the electrical components connected thereto from external physical impact.

[0050] A module frame (200) according to an embodiment of the present invention may have a monoframe structure covering four sides, excluding the front and rear sides of a battery cell stack (120). First, the monoframe may be in the form of a metal plate with an integrated top surface, bottom surface, and both sides, and may be manufactured by extrusion molding. The monoframe may be a frame that requires horizontal assembly to insert the battery cell stack (120) into the monoframe. However, the module frame is not limited to a monoframe and may be in the form of a U-shaped frame with an open top surface, front surface, and rear surface, and an upper plate covering the top of the battery cell stack (120). Furthermore, in the case of a moduleless structure, the module frame may be omitted, and the battery cell stack (120) may be directly mounted to the pack frame.

[0051] A thermally conductive resin may be injected between the lower surface of the battery cell stack (120) and the module frame (200), and a thermally conductive resin layer (not shown) may be formed between the lower surface of the battery cell stack (120) and the module frame (200) through the injected thermally conductive resin.

[0052] Meanwhile, the module frame (200) may be opened in the direction in which the electrode leads (111, 112) protrude (x-axis direction, -x-axis direction), and a first end plate (410) and a second end plate (420) may be positioned on each of the open sides of the module frame (200). The first end plate (410) may be joined to the module frame (200) while covering the first bus bar frame (310), and the second end plate (420) may be joined to the module frame (200) while covering the second bus bar frame (not shown). That is, the first bus bar frame (310) may be positioned between the first end plate (410) and the battery cell stack (120), and the second bus bar frame (not shown) may be positioned between the second end plate (420) and the battery cell stack (120). Additionally, an insulating cover (800, see FIG. 1) for electrical insulation may be located between the first end plate (410) and the first bus bar frame (310).

[0053] The first end plate (410) and the second end plate (420) are positioned to cover the one side and the other side, respectively, of the battery cell stack (120). The first end plate (410) and the second end plate (420) can protect the first bus bar frame (310) and various electrical components connected thereto from external impacts, and for this purpose, they must have a certain strength and may include a metal such as aluminum. Additionally, the first end plate (410) and the second end plate (420) can each be joined to the corresponding corner of the module frame (200) by means such as welding.

[0054] The first bus bar frame (310) is positioned on one side of the battery cell stack (120) to cover the battery cell stack (120) and simultaneously guide the connection between the battery cell stack (120) and an external device. Specifically, at least one of a bus bar, a terminal bus bar, and a module connector may be mounted on the first bus bar frame (310). In particular, at least one of a bus bar, a terminal bus bar, and a module connector may be mounted on the side opposite to the side of the first bus bar frame (310) facing the battery cell stack (120). For example, FIG. 2 shows a bus bar (510) and a terminal bus bar (520) mounted on the first bus bar frame (310).

[0055] Battery cells (110) constituting a battery cell stack (120) can be connected in series or in parallel by a bus bar (510) or a terminal bus bar (520), and the battery cells (110) can be electrically connected to an external device or circuit through a terminal bus bar (520) exposed to the outside of the battery module (105). For example, the terminal bus bar (520) can be connected to an external bus bar that allows the battery module containing the terminal bus bar (520) to be connected to another battery module adjacent to it.

[0056] The first bus bar frame (310) may include an electrically insulating material. The first bus bar frame (310) may prevent a short circuit by restricting the bus bar (510) or terminal bus bar (520) from contacting the battery cells (110), except for the portion where the bus bar (510) or terminal bus bar (520) is joined to the electrode lead (111).

[0057] Meanwhile, as described above, a second bus bar frame may be positioned on the other side of the battery cell stack (120), and a bus bar and a module connector may be mounted on the second bus bar frame. An electrode lead (112) may be bonded to this bus bar.

[0058] An opening may be formed in the first end plate (410) according to the present embodiment to expose a terminal bus bar (520). The opening may be a terminal bus bar opening. For example, as shown in FIGS. 1 and 2, a terminal bus bar opening (410H) to expose a terminal bus bar (520) may be formed in the first end plate (410). The terminal bus bar (520) further includes an upwardly protruding portion compared to the bus bar (510), and this upwardly protruding portion may be exposed to the outside of the battery module (100) through the terminal bus bar opening (410H). The terminal bus bar (520) exposed through the terminal bus bar opening (410H) may be connected to another battery module or a BDU (Battery Disconnect Unit) to form a High Voltage (HV) connection.

[0059] The battery unit (100) according to the present embodiment described above is described based on the battery module (105). The battery module (105) according to the present embodiment may include a battery cell stack (120), a module frame (200) that houses the same, a bus bar frame (310), and end plates (410, 420). At this time, the battery unit (100) according to the present embodiment may include the battery module (105) and a cooling plate (500) located at the bottom of the battery module (105).

[0060] Figure 4 is a diagram showing the flow of refrigerant in the cooling plate of Figure 1.

[0061] Referring to FIGS. 1 and 4, the cooling plate (500) according to the present embodiment includes two inlets (510, 512; inlet) formed at different locations through which refrigerant is introduced, and an outlet (515; outlet) through which the refrigerant is discharged. The two inlets may include a first inlet (510) and a second inlet (512). At this time, the outlet (515) may be positioned between the first inlet (510) and the second inlet (512). Through the first inlet (510), the refrigerant may be introduced into the first cooling section (520) in the -y-axis direction, through the second inlet (512), the refrigerant may be introduced into the second cooling section (522) in the -y-axis direction, and through the outlet (515), the refrigerant may be discharged in the y-axis direction.

[0062] Specifically, the cooling plate (500) according to the present embodiment may include a first cooling section (520) including a first cooling channel (501) connected to a first inlet (510), a second cooling section (522) including a second cooling channel (502) connected to a second inlet (512), and a third cooling section (525) including a third cooling channel (503) connected to an outlet (515).

[0063] The first cooling section (520) may be positioned at the front end of the cooling plate (500), the second cooling section (522) may be positioned at the rear end of the cooling plate (500), and the third cooling section (525) may be positioned at the center of the cooling plate (500). Here, the front end of the cooling plate (500) corresponds to the front end of the battery unit (100) of FIG. 1, the rear end of the cooling plate (500) corresponds to the rear end of the battery unit (100), and the center of the cooling plate (500) corresponds to the center of the battery unit (100).

[0064] The structure of the cooling plate (500) may be in the form of a lower plate and an upper plate facing each other, although not illustrated. A plurality of cooling channels (501, 502, 503) may be formed so that refrigerant supplied into the cooling plate (500) through the first and second inlets (510, 512) flows. The cooling channels (501, 502, 503) may have a structure in which the lower plate is formed to be recessed downward, thereby forming a space for the refrigerant to flow between the upper plate and the lower plate.

[0065] The cooling plate (500) structure described above is an example, and as a modified embodiment, a flat upper plate and a flat lower plate are combined, and an internal support having a bead structure protruding from the lower plate may be disposed between them. At this time, a cooling channel (501, 502, 503) may be formed by the bead structure between the upper plate and the lower plate. As another modified embodiment, the cooling plate (500) may have the bottom part of the module frame (200) acting as the upper plate without an upper plate, so that a cooling channel (501, 502, 503) is formed in the space between the lower plate and the bottom part of the module frame (200).

[0066] According to the present embodiment, the direction in which refrigerant flows in through the first inlet (510) (A1; -y-axis direction), the direction in which refrigerant flows in through the second inlet (512) (A2; -y-axis direction), and the direction in which refrigerant is discharged through the outlet (515) (A3; y-axis direction) may be parallel to each other. In the embodiment of FIG. 4, the refrigerant inflow direction of the first and second inlets (510, 512) was described as being the same, but the refrigerant inflow directions of the first and second inlets (510, 512) may be parallel to each other and different directions, for example, the refrigerant inflow direction of the first inlet (510) may be the -y-axis direction and the refrigerant inflow direction of the second inlet (512) may be the y-axis direction. Similarly, the refrigerant inflow direction of the outlet (515) may be the y-axis direction.

[0067] Figure 5 is a diagram showing the arrangement relationship between the battery cell stack and the cooling plate in the battery unit of Figure 1.

[0068] Referring to FIGS. 1, 4, and 5, in the battery unit (100) according to the present embodiment, the battery cell stack (120) overlaps with the cooling plate (500) in the vertical direction (z-axis direction). At this time, according to the present embodiment, the direction (A1, A2) in which the refrigerant is introduced through the first inlet (510) and the second inlet (512) is parallel to the direction in which a plurality of battery cells (110) are stacked in the battery cell stack (120). The direction in which the refrigerant is discharged through the outlet (515) is parallel to the direction in which a plurality of battery cells (110) are stacked.

[0069] The battery cell (110) according to the present embodiment may include electrode leads (111, 112) protruding in directions facing each other. For example, the length direction of the battery cell (110) may be defined as the x-axis direction shown in FIG. 5, and the first electrode lead (111) and the second electrode lead (112) may be located on different sides with respect to the length direction of the battery cell (110).

[0070] A first electrode lead (111) protruding from a battery cell (110) may be positioned adjacent to a first inlet (510), and a second electrode lead (112) protruding from a battery cell (110) may be positioned adjacent to a second inlet (512). A plurality of first electrode leads (111) and second electrode leads (112) may be formed by protruding from each of the plurality of battery cells (110) included in the battery cell stack (120). Among the plurality of electrode leads, a first electrode lead (111) protruding from a first outermost battery cell (110) may be adjacent to a first inlet (510), and a second electrode lead (112) protruding from a second outermost battery cell (110) may be adjacent to a second inlet (512).

[0071] The first outermost battery cell (110) and the second outermost battery cell (110) may be placed on the same side or opposite sides. For example, the first and second outermost battery cells (110) may be the battery cells (110) placed on the far left or far right in FIG. 5. Alternatively, the first outermost battery cell (110) may be the battery cell (110) placed on the far left in FIG. 5 and the second outermost battery cell (110) may be the battery cell (110) placed on the far right, or the first outermost battery cell (110) and the second outermost battery cell (110) may be placed opposite each other.

[0072] According to the present embodiment, a plurality of first electrode leads (111) may be formed in the first cooling section (520), and a plurality of second electrode leads (112) may be formed in the second cooling section (522). The first cooling section (520) may be positioned at the front end of the cooling plate (500), the second cooling section (522) may be positioned at the rear end of the cooling plate (500), and the third cooling section (525) may be positioned at the center of the cooling plate (500). The front end and the rear end of the cooling plate (500) may each be a portion that overlaps vertically with the area where the bus bar frame (310) and end plates (410, 420) of FIG. 2 are formed.

[0073] As illustrated in FIG. 4, a refrigerant may flow through the first cooling channel (501) in the first cooling section (520), a refrigerant may flow through the second cooling channel (502) in the second cooling section (522), and a refrigerant may flow through the third cooling channel (503) in the third cooling section (525). The direction in which the first cooling channel (510) extends may be perpendicular to the direction in which the first electrode lead (111) protrudes, and the direction in which the second cooling channel (502) extends may be perpendicular to the direction in which the second electrode lead (112) protrudes. The first cooling channel (501) may overlap vertically with a plurality of first electrode leads (111) protruding from a plurality of battery cells (110), and the second cooling channel (502) may overlap vertically with a plurality of second electrode leads (112) protruding from a plurality of battery cells (110).

[0074] Accordingly, the refrigerant is first supplied to the cooling plate (500) through the first inlet (510) and the second inlet (512), so that the first and second cooling paths (501, 502) connected to the first and second inlets (510, 512), respectively, and the plurality of first electrode leads (111) and the plurality of second electrode leads (112) that overlap vertically can be cooled first. The central part of the battery cell (110) that overlaps vertically with the third cooling path (503) connected to the outlet (515) can be cooled with the refrigerant in a state where the temperature has risen slightly.

[0075] As such, according to the present embodiment, the first electrode lead (111) and the second electrode lead (112), which generate the most heat during charging and discharging, are cooled simultaneously first to improve the temperature difference with the central part of the battery cell (110).

[0076] Figure 6 is a diagram showing the flow of refrigerant in a cooling plate according to a comparative example. Figure 7 is a diagram showing the arrangement relationship between the cooling plate of Figure 6 and the battery cell stack.

[0077] Referring to FIG. 6, the cooling plate (50) according to the comparative example includes one inlet (12) and one outlet (15), and the refrigerant supplied through the inlet (12) can flow in the first cooling section (22) through the first cooling channel (32) connected to the inlet (12) and can flow in the second cooling section (25) through the second cooling channel (35) connected to the first cooling channel (32). The refrigerant that has passed through the second cooling channel (35) can be discharged out of the cooling plate (50) through the outlet (15).

[0078] Referring to FIGS. 6 and 7, the cooling plate (50) according to the comparative example can be vertically overlapped with the battery cell stack (11). In the cooling plate (50), the direction (B1) in which the refrigerant is introduced through the inlet (12) and / or the direction (B2) in which the refrigerant is discharged through the outlet (15) is perpendicular to the direction (y-axis direction) in which a plurality of battery cells (10) included in the battery cell stack (11) are stacked. A portion of the electrode leads (21) protruding from each of the plurality of battery cells (10) can be vertically overlapped with the first cooling section (22), and another portion of the electrode leads (21) can be vertically overlapped with the second cooling section (25). At this time, the temperature of the refrigerant flowing through the second cooling section (35) connected to the outlet (15) is higher than the temperature of the refrigerant flowing through the first cooling section (32) connected to the inlet (12). Accordingly, compared to the battery cell (10) that is cooled by overlapping the first cooling section (22) vertically, the cooling performance of the battery cell (10) that is cooled by overlapping the second cooling section (25) vertically is reduced, so the temperature difference between the battery cells (10) included in the battery cell stack (11) may increase. On the other hand, according to the embodiment of the present invention described above, by positioning two inlets on each electrode lead where heat generation is most severe during charging and discharging, the first electrode lead and the second electrode lead are simultaneously cooled first with the inlet refrigerant with the lowest temperature, thereby improving the temperature difference with the central part of the battery cell.

[0079]

[0080] FIG. 8 is a perspective view showing a two-layer cooling plate structure according to another embodiment of the present invention.

[0081] The cooling plate structure according to the present embodiment includes a lower cooling plate (600) comprising a first cooling section (620), a second cooling section (622), and a third cooling section (625), and an upper cooling plate (700) comprising a fourth cooling section (720) connected to the first cooling section (620), a fifth cooling section (722) connected to the second cooling section (622), and a sixth cooling section (725) connected to the third cooling section (625).

[0082] The cooling plate (500) structure described in FIGS. 1 to 5 above may correspond to the lower cooling plate (600) according to the present embodiment. In other words, the cooling plate structure according to the present embodiment may further include an upper cooling plate (700) and the first, second, and third connecting parts described later, in the cooling plate (500) structure according to the embodiment of FIGS. 1 to 5.

[0083] According to the present embodiment, the fourth cooling unit (720) is connected to the first cooling unit through a first connecting unit (630) extending in the vertical direction, the fifth cooling unit (722) is connected to the second cooling unit (622) through a second connecting unit (632) extending in the vertical direction, and the sixth cooling unit (725) can be connected to the third cooling unit (625) through a third connecting unit (635) extending in the vertical direction.

[0084] In the first connection part (630) and the second connection part (632), the refrigerant may flow upward, and in the third connection part (635), the refrigerant may flow downward.

[0085] Although not illustrated, in the cooling plate structure according to the present embodiment, an object to be cooled may be placed in the space between the lower cooling plate (600) and the upper cooling plate (700). For example, the battery module (105) described in FIG. 1 may be placed therein.

[0086]

[0087] In the cooling plate structure according to the present embodiment, the lower cooling plate (600) may have a larger area than the upper cooling plate (700). In the portion of the lower cooling plate (600) that has a larger area than the upper cooling plate (700) without overlapping with the upper cooling plate (700), first and second inlets (610, 612) and an outlet (615) may be connected.

[0088] According to the present embodiment, by cooling the object to be cooled not only at the bottom but also at the top, the temperature difference that may occur between the upper and lower parts of the battery cell can also be improved.

[0089] In addition to the differences explained above, the contents described in FIGS. 1 to 5 are all applicable to this embodiment.

[0090] Meanwhile, one or more battery modules included in the battery unit according to the present embodiment may be packaged within a pack case to form a battery pack.

[0091] The battery module and the battery pack containing the same described above can be applied to various devices. Such devices may be applied to means of transportation such as electric bicycles, electric vehicles, and hybrid vehicles, but the present invention is not limited thereto and can be applied to various devices capable of using the battery module and the battery pack containing the same, and this also falls within the scope of the present invention.

[0092] The battery module or battery pack described in this specification may be included in a battery unit.

[0093] Although preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims also fall within the scope of the present invention.

[0094] [Explanation of the symbol]

[0095] 100: Battery unit

[0096] 105: Battery Module

[0097] 120: Battery cell stack

[0098] 500: Cooling plate

[0099] 501, 502, 502: Cooling channels

[0100] 510, 512: Inlet

[0101] 515: Outlet

[0102] 520, 522, 525, 620, 622, 625, 720, 722, 725: Cooling section

[0103] 630, 632, 635: Connections

Claims

1. A battery cell stack comprising a plurality of battery cells, and It includes a cooling plate for cooling the above-mentioned battery cell stack, and The above cooling plate includes two inlets formed at different locations through which refrigerant flows, and an outlet through which the refrigerant is discharged. The above two inlets include a first inlet and a second inlet, The direction in which the refrigerant flows through the first inlet and the second inlet is parallel to the direction in which the plurality of battery cells are stacked in the battery unit.

2. In Paragraph 1, A battery unit in which the first inlet is located adjacent to a first electrode lead protruding from the first outermost battery cell among the battery cells, and the second inlet is located adjacent to a second electrode lead protruding from the second outermost battery cell among the battery cells, and the first outermost battery cell and the second outermost battery cell are arranged on the same side or opposite sides.

3. In Paragraph 2, The first electrode lead and the second electrode lead are battery units located on different sides with respect to the longitudinal direction of the battery cell.

4. In Paragraph 2, A battery unit in which the direction in which the refrigerant is discharged through the above outlet is parallel to the direction in which the plurality of battery cells are stacked.

5. In Paragraph 2, The above cooling plate includes a first cooling section including a first cooling channel connected to the first inlet, a second cooling section including a second cooling channel connected to the second inlet, and a third cooling section including a third cooling channel connected to the outlet. A battery unit wherein the first cooling unit is positioned at the front end of the cooling plate, the second cooling unit is positioned at the rear end of the cooling plate, and the third cooling unit is positioned at the center of the cooling plate.

6. In Paragraph 5, A battery unit in which the direction in which the first cooling channel extends is perpendicular to the direction in which the first electrode lead protrudes, and the direction in which the second cooling channel extends is perpendicular to the direction in which the second electrode lead protrudes.

7. In Paragraph 6, A battery unit in which the first cooling channel overlaps vertically with a plurality of first electrode leads protruding from each of the plurality of battery cells, and the second cooling channel overlaps vertically with a plurality of second electrode leads protruding from each of the plurality of battery cells.

8. In Paragraph 5, When the portion including the first cooling portion, the second cooling portion, and the third cooling portion is referred to as the lower cooling plate, the cooling plate further includes an upper cooling plate including a fourth cooling portion connected to the first cooling portion, a fifth cooling portion connected to the second cooling portion, and a sixth cooling portion connected to the third cooling portion. The above-mentioned fourth cooling unit is connected to the first cooling unit through a first connecting unit extending in the vertical direction, and The above-mentioned fifth cooling unit is connected to the second cooling unit through a second connecting unit extending in the vertical direction, and The above-mentioned sixth cooling unit is connected to the above-mentioned third cooling unit through a third connecting unit extending in the vertical direction, and A battery unit in which the refrigerant flows upward in the first and second connecting parts, and the refrigerant flows downward in the third connecting part.

9. In Paragraph 8, The lower cooling plate above is a battery unit having a larger area than the upper cooling plate.

10. Two inlets formed at different locations through which refrigerant flows, and It includes an outlet through which the above-mentioned refrigerant is discharged, The above two inlets include a first inlet and a second inlet, A cooling plate in which the direction in which the refrigerant flows in through the first inlet, the direction in which the refrigerant flows in through the second inlet, and the direction in which the refrigerant is discharged through the outlet are parallel to each other.

11. In Paragraph 10, The above outlet is a cooling plate positioned between the two inlets.

12. In Paragraph 10, The above cooling plate includes a first cooling section including a first cooling channel connected to the first inlet, a second cooling section including a second cooling channel connected to the second inlet, and a third cooling section including a third cooling channel connected to the outlet. A cooling plate wherein the first cooling portion is disposed at the front end of the cooling plate, the second cooling portion is disposed at the rear end of the cooling plate, and the third cooling portion is disposed at the center of the cooling plate.

13. In Paragraph 12, When the portion including the first cooling portion, the second cooling portion, and the third cooling portion is referred to as the lower cooling plate, the upper plate further includes a fourth cooling portion connected to the first cooling portion, a fifth cooling portion connected to the second cooling portion, and a sixth cooling portion connected to the third cooling portion. The above-mentioned fourth cooling unit is connected to the first cooling unit through a first connecting unit extending in the vertical direction, and The above-mentioned fifth cooling unit is connected to the second cooling unit through a second connecting unit extending in the vertical direction, and The above-mentioned sixth cooling unit is connected to the above-mentioned third cooling unit through a third connecting unit extending in the vertical direction, and A cooling plate in which the refrigerant flows upward in the first and second connecting portions, and the refrigerant flows downward in the third connecting portion.

14. In Paragraph 13, The lower cooling plate is a cooling plate having a larger surface area than the upper cooling plate.

15. In Paragraph 13, A cooling plate in which the first inlet, the second inlet, and the outlet are formed on the same side of the cooling plate, and the first connection, the second connection, and the third connection are formed on the same other side of the cooling plate.

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