KR101783515B1 - Cooling plate for secondary battery and secondary battery module - Google Patents

Abstract

The present invention relates to a cooling plate for a secondary battery and a secondary battery module including the cooling plate, wherein the cooling plate is provided with a cooling part having a mesh structure penetrating in the thickness direction of the cooling plate on a flat plate surface of the cooling plate.
The secondary battery module according to the present invention minimizes the deformation of the cooling plate when the battery module passes through the battery module due to external impact and stimulation and consequently reduces the influence of deformation of the cooling plate on the unit cell, Lt; RTI ID = 0.0 > stability. ≪ / RTI >

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a cooling plate for a secondary battery,

The present invention relates to a cooling plate for a secondary battery and a secondary battery module including the same, which can minimize the deformation when passing through the battery module due to external impact and stimulation and reduce the influence on the adjacent unit cells as a result, .

As technology development and demand for mobile devices are increasing, the demand for batteries as energy sources is rapidly increasing, and accordingly, a lot of researches on batteries capable of meeting various demands have been conducted.

Typically, there is a high demand for a pouch-type secondary battery that can be applied to products such as mobile phones with a thin thickness in terms of the shape of the battery. In terms of materials, lithium ion batteries having high energy density, discharge voltage and output stability, lithium- The demand for secondary batteries is high.

Generally, a secondary battery may have various shapes such as a cylindrical shape and a square shape. When the secondary battery is used to drive a motor such as an electric vehicle, which requires large power, a plurality of secondary batteries are connected in series as a unit battery, Capacity secondary battery assembly (hereinafter referred to as " battery module ").

Wherein each of the unit cells constituting the battery module includes a battery case having an electrode assembly in which a positive electrode plate and a negative electrode plate are stacked with a separator interposed therebetween, and a space portion in which the electrode assembly is housed, An amount of the electrode assembly, and an electrode terminal electrically connected to the current collector of the negative electrode plate and the negative electrode plate. In the case of a prismatic secondary battery, for example, each unit cell is configured such that a cathode terminal and a cathode terminal protruding from the upper portion of the battery case are arranged to be offset from a cathode terminal and an anode terminal of a neighboring unit cell, Thereby constituting a battery module. At this time, since several to several tens of unit cells are connected to each other, the heat generated from each unit cell must be easily discharged.

The heat release characteristic of the battery module is very important so as to influence the performance of the battery. If the heat is not properly discharged, the heat generated in the unit cell may cause a rise in the temperature inside the battery, which may deteriorate battery performance and cause a risk of explosion. In particular, when the battery module is applied as a large-capacity secondary battery for driving an electric vacuum cleaner, an electric scooter or an automobile motor, since the battery is charged and discharged with a large current, the temperature of the battery rises to a considerable temperature due to heat generated inside the battery do.

Accordingly, it is required to develop a cooling plate capable of effectively emitting heat generated in the battery module.

Korean Patent Publication No. 2012-0048938 (published May 16, 2012)

SUMMARY OF THE INVENTION A first technical problem to be solved by the present invention is to provide a battery module that minimizes deformation when passing through a battery module due to external impact and stimulation and consequently reduces the effect on an adjacent unit cell, And to provide a cooling plate for a secondary battery that can improve the safety of the back-up battery.

A second technical problem to be solved by the present invention is to provide a secondary battery module and a battery pack including the cooling plate.

However, the technical problem to be solved by the present invention is not limited to the above-mentioned problems, and other matters not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a plate-type cooling plate, comprising: a cooling plate for a secondary battery provided with a cooling section having a mesh structure penetrating in a thickness direction of a cooling plate, Lt; / RTI >

According to another embodiment of the present invention, there is provided a secondary battery module in which a plurality of unit cells capable of charging and discharging are arranged at intervals, the secondary battery module including the cooling plate interposed between the unit cells do.

Further, the present invention provides a battery pack including the secondary battery module.

Other details of the embodiments of the present invention are included in the following detailed description.

The cooling plate for a secondary battery according to the present invention minimizes the deformation of the cooling plate when the battery module passes through the battery module due to external impact and stimulation and consequently reduces the influence of deformation of the cooling plate on the unit cell, The cell safety can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments of the invention and, together with the description of the invention, It should not be construed as limited.
1 is a perspective view illustrating a cooling plate in a secondary battery module according to an embodiment of the present invention.
Fig. 2 schematically shows deformation of a cooling plate during a nail penetration test in a secondary battery module including a conventional cooling plate.
3 is a schematic view illustrating a modification of a cooling plate during a nail penetration test in a secondary battery module including a cooling plate according to an embodiment of the present invention.
4 is an exploded perspective view schematically illustrating a structure of a secondary battery module according to another embodiment of the present invention.

Hereinafter, the configuration and operation according to the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description with reference to the accompanying drawings, the same reference numerals denote the same elements regardless of the reference numerals, and redundant description thereof will be omitted. The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

1 is a perspective view schematically showing a structure of a cooling plate for a secondary battery according to an embodiment of the present invention. FIG. 1 is an illustration for illustrating the present invention, but the present invention is not limited thereto.

1, a cooling plate 20 for a secondary battery according to an embodiment of the present invention is a flat plate type cooling plate. The plate is provided with a through-hole in the thickness direction (y-axis direction) And a cooling unit 21 having a mesh structure.

Generally, the cooling plate intervenes between the unit cells to prevent the unit cells from expanding and breaking, and rapidly discharges the heat generated by the unit cells to increase the cooling efficiency of the unit cells.

As the conventional cooling plate, a plate-type cooling plate made mainly of aluminum was used, and the cooling plate was closely attached between the unit cells without a space in the battery module. As a result, when an external impact such as a nail penetration test is applied, deformation in the vertical direction occurs in the cooling plate, and the lower end unit cell is deformed to cause a short circuit.

On the contrary, in the present invention, by applying a cooling plate of a mesh type that can minimize the deformation in the vertical direction by opening the empty space of the cooling plate as much as the nail is inserted in the nail penetration test, The cooling efficiency is further improved and the deformation of the cooling plate is minimized when the battery module is penetrated by the external impact and the magnetic pole so that the influence of deformation of the cooling plate on the adjacent unit cells is reduced, Can be prevented.

FIG. 2 is a schematic view illustrating deformation of a cooling plate during a nail penetration test in a secondary battery module including a conventional cooling plate, and FIG. 3 is a cross-sectional view of a secondary battery module including a cooling plate according to an embodiment of the present invention. The deformation of the cooling plate during the nail penetration test is schematically shown. 2 and 3 (a) show the cooling plate before the penetration test, and (b) show the cooling plate after the penetration test.

As shown in FIGS. 2 and 3, when the nail is inserted, the conventional plate is deformed to generate a hole in a vertical direction. However, the cooling plate according to an embodiment of the present invention may have a hollow space do. As a result, the deformation in the vertical direction can be minimized.

Specifically, the cooling plate 20 for a secondary battery according to an embodiment of the present invention has a flat plate shape and has a mesh structure penetrating in the thickness direction (y-axis direction) of the cooling plate on the flat plate surface of the cooling plate A cooling section 21 is provided.

More specifically, in the cooling plate, the cooling section 21 includes a plurality of openings 21a penetrating in the thickness direction of the cooling plate and a partition 21b for partitioning between the openings.

The opening 21a may have various shapes such as a circle, an ellipse, a triangle, a square, a rectangle, a pentagon, a hexagon, or a rhombus. The opening 21a may have any one of the above-described shapes, or may have a shape in which two or more shapes are mixed. More specifically, the opening may have a square, hexagonal or rhombic shape.

In addition, the openings 21a may have the same size and shape, and may have different sizes or shapes. More specifically, the opening 21a may have the same size and shape in consideration of cooling efficiency and penetration pressure absorption efficiency.

In the cooling section 21, the width of the partition for partitioning the openings may be 0.1 mm to 1 mm. When the width of the compartment is within the above-mentioned range, the cooling plate, particularly the cooling part, can exhibit sufficient mechanical strength. More specifically, the width of the partition may be 0.5 mm to 1 mm.

More specifically, in the cooling plate 20 for a secondary battery according to an embodiment of the present invention, the cooling unit 21 may be a mesh network in which wire-shaped wires are staggered in a grid shape. Further, a welding portion may be further provided for fixing at the overlapping portion of the wire rod.

The diameter of the wire material constituting the mesh net may be 0.1 mm to 1 mm.

In the unit cell, the distance a between two corners located in the diagonal direction may be 10 mm or less. If the distance a between the two corners exceeds 10 mm, the absorption effect of the penetration pressure and the cooling efficiency may be lowered. More specifically, it may be 2 mm to 7 mm.

Also, in the cooling plate 20 for a secondary battery according to an embodiment of the present invention, the cooling unit 21 may be a honeycomb mesh network having hexagonal openings of the same size.

When the cooling unit 21 has a honeycomb shape, the diameter of the wire constituting the honeycomb-shaped mesh net may be 0.1 mm to 1 mm. In addition, the distance a between two opposite sides parallel to each other in the hexagonal opening constituting the honeycomb may be 10 mm or less. If the distance (a) between the two sides exceeds 10 mm, the absorption effect of the penetration pressure and the cooling efficiency may be lowered. More specifically, it may be 2 mm to 7 mm.

The cooling unit 21 as described above is brought into contact with the front surface of one side of the unit cell. Accordingly, the cooling unit may have a size corresponding to that of the unit cell.

The cooling plate 20 may further include a reinforcing portion 22 surrounding the upper surface of the cooling portion 21 or the outer surface of the cooling portion 21.

When the reinforcing part 22 is positioned on the upper part of the upper part of the cooling part, that is, on the upper surface and the lower surface of the cooling part in the z-axis direction, it functions to install and support the cooling plate in the secondary battery module. Specifically, when the cooling unit is located on the four sides of the upper, lower, left, and right sides of the cooling unit in the x-axis and y-axis directions, It can play a protective role.

In this case, the entire surface of the cooling part 21 of the cooling plate 20 is in contact with the entire one side of the unit cell, and the reinforcing part 22 passes the outside of the unit cell.

Specifically, when the reinforcing portion 22 is positioned on the upper portion of the cooling portion, the reinforcement portion 22 may be a rectangular flat plate. When the reinforcing portion 22 is positioned to surround the outer surface of the cooling portion, Frame.

The cooling plate having the above structure may be an integrated type in which the cooling part is integrated or an assembled type in which the cooling part is separately manufactured and assembled. Accordingly, the manufacturing method thereof may be changed.

Specifically, when the cooling unit 21 is integrated, casting is performed using a patterned mold so as to form a mesh structure, or a cooling unit is formed through an opening forming process such as punching for a cooling plate forming flat plate Can be manufactured. Alternatively, the wire may be manufactured by weaving using a wire-shaped wire, and a welding process may be further performed on the intersection portion of the woven wire if necessary.

If the cooling unit 21 is of an assembled type, it may be formed by inserting a structure having a mesh structure, for example, a metal mesh or the like, into a frame for forming a cooling plate having a storage space for accommodating the cooling unit. At this time, the frame for forming the cooling plate may be a reinforcing portion 22 in the cooling plate finally manufactured.

When the cooling plate further includes the reinforcing portion 22, the cooling plate 21 may be integrally formed with the cooling portion 21 on the cooling portion 21, or may be formed as a separate member from the cooling portion 21 Welding or the like.

The material of the cooling plate 20 is not particularly limited as long as it is usually used for manufacturing a cooling plate. Specifically, examples include aluminum, aluminum alloy, stainless steel, copper, silver, aluminum oxide, and the like, alone or in a mixture of two or more. More specifically, the cooling plate 20 may comprise aluminum or an aluminum alloy.

The cooling portion and the reinforcing portion in the cooling plate may include the same material of the cooling plate, or may include materials different from each other.

The thickness of the cooling plate 20 may be 1 mm to 3 mm, more specifically, 1 mm to 2 mm.

The cooling plate 20 preferably has an aperture ratio of 50% by volume to 90% by volume based on the total volume of the cooling plate. When the opening ratio is within the above range, it is possible to simultaneously prevent deformation of the cooling plate and improve the cooling efficiency. If the opening ratio is less than 50% by volume, the discharge or cooling effect on the heat generated by the unit cell is low, and if it exceeds 90% by volume, the mechanical strength of the cooling plate may be lowered.

The cooling plate 20 may be used as a single layer or as a multi-layered structure of two or more layers.

According to another embodiment of the present invention, there is provided a secondary battery module including the cooling plate.

Specifically, in the secondary battery module, a plurality of unit cells capable of charging and discharging are arranged with an interval, and the cooling plate is interposed between the unit cells.

4 is an exploded perspective view schematically illustrating a structure of a secondary battery module according to an embodiment of the present invention. Fig. 4 is an illustration for explaining the present invention, but the present invention is not limited thereto.

Referring to FIG. 4, a secondary battery module 10 according to an embodiment of the present invention includes a plurality of unit cells 11 that are chargeable and dischargeable with a space therebetween, And a cooling section 21 having a mesh structure penetrating in the thickness direction of the cooling plate is provided on the flat plate surface of the cooling plate.

More specifically, the secondary battery module 10 is configured such that a plurality of unit cells are electrically connected in series or in parallel by a connector (not shown) and are tightened and modulated by a coupling band (not shown) The secondary battery module 10 includes a cooling plate 20 disposed between the unit cells 11. The secondary battery module 10 may further include an end plate (not shown) for preventing breakage of the unit cell 11 when the fastening band is fastened.

The secondary battery module may be installed in a separate housing (not shown) constituting the outer case. The cooling air supplied to the housing passes through the cooling plate 20 interposed between the unit cells 11, In this process, the heat generated in the unit cell is exchanged, and the exchanged air is discharged to the outside of the housing, thereby releasing the heat generated in the unit cell to the outside.

In addition, the cooling plate 20 may be a single structure having the above cooling portion, or may be a laminated structure of two or more layers.

Meanwhile, in the secondary battery module 10, the unit cell 11 includes an electrode assembly in which a positive electrode plate and a negative electrode plate are positioned with a separator interposed therebetween, and is included in a form housed in a battery case .

Specifically, the unit cell 11 includes an electrode assembly, a battery case having an internal space capable of accommodating the electrode assembly, a battery case having one end (e.g., one end) connected to the electrode assembly, The other end may include an electrode lead of positive and negative electrodes protruding from the battery case, and a sealing part sealing the inlet of the battery case.

The battery case of the unit cell 11 may be a pouch-shaped battery case composed of an upper laminate sheet and a lower laminate sheet, and the upper laminate sheet and the lower laminate sheet are thermally fused together along the outer circumferential surface of the battery case A sealing part may be provided.

The upper laminate sheet constituting the battery case may be a laminate sheet including a metal layer and a resin layer covering the metal layer. More specifically, a polyolefin resin layer (polyolefin layer), which is an inner layer having a thermo-compression property and serves as a sealing material, a metal foil layer (mainly an aluminum layer) that maintains mechanical strength and serves as a barrier layer of moisture and oxygen, And an outer layer (mainly a nylon layer) serving as a protective layer are sequentially laminated on the substrate. Commonly used as a polyolefin-based resin layer is CPP (Casted Polypropylene).

The sealing portion is formed by thermally compressing the resin layer by applying heat and pressure to the outer circumferential surface portion where the upper laminate sheet and the lower laminate sheet of the battery case are in contact with each other. At this time, since the outer circumferential surface portion where the electrode lead is not laid is the same resin layer as the upper laminate sheet, uniform sealing is possible by direct melting. Specifically, the thermocompression bonding process may be performed at a temperature of 120 ° C to 250 ° C and a pressure of 0.1 MPa to 10 MPa using an electric heat and a press.

On the other hand, since the electrode leads protrude from the outer circumferential surface of the upper end of the battery case, on which the electrode leads are placed, in order to increase the sealing property in consideration of the thickness of the electrode leads and the heterogeneity with the battery case material, But it is not necessarily limited to this.

In addition, the electrode assembly is not particularly limited as long as it has a structure in which a plurality of electrode tabs are connected to form an anode and a cathode.

Specifically, the electrode assembly may include a positive electrode plate including a positive electrode active material coating portion on at least one surface of a positive electrode collector, and a negative electrode plate including a negative electrode active material coating portion on at least one surface of the negative electrode collector, have.

The electrode assembly includes a positive electrode plate including a positive electrode active material coating portion on at least one surface of a positive electrode collector, and a negative electrode plate including a negative electrode active material coating portion on at least one surface of the negative electrode collector, Lt; / RTI >

The electrode assembly includes a positive electrode plate including a positive electrode active material coating portion on at least one surface of a positive electrode collector and a negative electrode plate including a negative electrode active material coating portion on at least one surface of the negative electrode collector stacked with a separator interposed therebetween, And each of the overlapping portions includes a separation film, and the separation film may be a stack-folding type electrode assembly that surrounds each unit electrode assembly.

The stacked and jelly-roll type structures are well known in the art, and a description thereof will be omitted herein. Further, details of the electrode assembly of the stack-folding type structure are disclosed in Korean Patent Application Publication Nos. 2001-0082058, 2001-0082059 and 2001-0082060 of the present applicant, As a reference.

More specifically, in the secondary battery according to an embodiment of the present invention, the electrode assembly may be a stack-folding type electrode assembly.

Meanwhile, in the electrode assembly, the negative electrode plate includes a negative electrode collector, and a negative electrode active material coating portion coated on at least one surface, preferably both surfaces, of the negative electrode collector.

In the negative electrode plate described above, the negative electrode collector is not particularly limited as long as it has high conductivity without causing a chemical change in the battery, and examples thereof include copper, stainless steel, aluminum, nickel, titanium, The surface of the stainless steel may be surface treated with carbon, nickel, titanium, or silver, or an aluminum-cadmium alloy may be used.

The negative electrode current collector may have a thickness of 3 to 500 mu m.

In addition, fine unevenness may be formed on the surface of the negative electrode collector to enhance the binding force of the negative electrode active material. For example, it can be used in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric.

The negative electrode active material coating portion includes a negative electrode active material, a binder, and a conductive material.

As the negative electrode active material, a compound capable of reversible intercalation and deintercalation of lithium may be used. Specific examples thereof include carbonaceous materials such as artificial graphite, natural graphite, graphitized carbon fiber and amorphous carbon; Metal compounds capable of alloying with lithium such as Si, Al, Sn, Pb, Zn, Bi, In, Mg, Ga, Cd, Si alloys, Sn alloys or Al alloys; Or composites comprising a metallic compound and a carbonaceous material; Or silicon-based compounds such as SiOx (0 < x < 2), and either one of them or a mixture of two or more thereof may be used. Also, a metal lithium thin film may be used as the negative electrode active material.

The binder serves to improve the adhesion between the anode active material particles and the adhesion between the anode active material and the anode current collector. Specific examples include polyvinylidene fluoride (PVDF), polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetrafluoroethylene, There can be mentioned polyethylene, polypropylene, ethylene-propylene-diene polymer (EPDM), sulfonated-EPDM, ethylene- (meth) acrylic acid copolymer, styrene-butadiene rubber, fluorine rubber or various copolymers thereof. One kind alone or a mixture of two or more kinds can be used.

The binder may include 1 to 30% by weight based on the total weight of the negative electrode active material coating portion.

The conductive material is used for imparting conductivity to the electrode. The conductive material is not particularly limited as long as it has electron conductivity without causing chemical change. Specific examples thereof include graphite such as natural graphite and artificial graphite; Carbon-based materials such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, summer black and carbon fiber; Metal powder or metal fibers such as copper, nickel, aluminum and silver; Conductive whiskey such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; And polyphenylene derivatives. These may be used alone or in admixture of two or more.

The conductive material may be included in an amount of 1 to 30% by weight based on the total weight of the negative electrode active material coating portion.

In addition, in the electrode assembly, the positive electrode plate includes a positive electrode collector and a positive electrode active material coating portion coated with a positive electrode active material on at least one surface, preferably both surfaces, of the positive electrode collector.

In the above-mentioned positive electrode plate, the positive electrode collector is not particularly limited as long as it has electrical conductivity without causing a chemical change in the battery. For example, stainless steel, aluminum, nickel, titanium, Such as carbon, nickel, titanium, or silver, may be used.

In addition, the cathode current collector may have a thickness of 3 to 500 탆, and fine unevenness may be formed on the surface of the cathode current collector to increase the adhesive force of the cathode active material. For example, it can be used in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric.

In the above-mentioned positive electrode plate, the positive electrode active material coating portion may be coated on both surfaces of the positive electrode collector, or the active material may be coated on only one side of the positive electrode collector. However, considering the capacity of the secondary battery, It may be more preferable to be coated.

The positive electrode plate may include insulating tapes at both ends of the positive electrode plate flat coating portion, that is, at the start portion and the end portion of the positive electrode plate flat coating portion, in order to prevent a short circuit in the charging and discharging process. At this time, the insulating tape may be the same as described in the cathode plate.

The positive electrode tab may be attached by welding such as laser welding, ultrasonic welding, resistance welding, or conductive adhesive, and an insulating tape may be attached to the positive electrode tab to prevent a short circuit between the electrodes.

The unit cell 11 includes electrode tabs extending from the electrode assembly, and electrode leads welded to the electrode tabs.

At this time, the electrode terminal may be positioned in one direction or both directions of the unit cell.

The electrode terminals may be electrically connected in series or in parallel at one or both sides of the battery module.

Meanwhile, in the electrode assembly, the separator interposed between the positive electrode plate and the negative electrode plate may be an insulating thin film having high ion permeability and mechanical strength.

Specifically, the separation membrane may be a porous polymer film such as a porous polymer film made of a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, and an ethylene / methacrylate copolymer Or a laminated structure of two or more thereof. The separation membrane may be a nonwoven fabric made of a porous nonwoven fabric, for example, glass fiber of high melting point or polyethylene terephthalate fiber.

In some cases, a gel polymer electrolyte may be coated on the separation membrane to improve the stability of the cell. Representative examples of such gel polymers include polyethylene oxide, polyvinylidene fluoride, polyacrylonitrile, and the like. When a solid electrolyte such as a polymer is used as an electrolyte, the solid electrolyte may also serve as a separation membrane.

The pores contained in the separation membrane may have a pore diameter of 0.01 to 10 탆.

In addition, the separation membrane may have a thickness of 5 to 300 탆.

In addition, it is preferable that the separation membrane is extended longer than the end of the cathode plate so as to block the cathode electrode even if the separation membrane is contracted by heat. Specifically, the separation membrane may extend from the cathode end portion by 5 mm or more.

According to another aspect of the present invention, there is provided a battery pack including the battery module.

The battery pack includes a power tool; An electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), and a plug-in hybrid electric vehicle (PHEV); Or a power storage system, as shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

( Example : Manufacture of Secondary Battery Module)

An Al cooling plate having a honeycomb-shaped mesh structure having a structure as shown in Fig. 1 was prepared (cooling plate thickness: 1.0 mm, aperture ratio: 80% by volume), and between two opposing sides in the hexagonal opening constituting the honeycomb Distance (a): 2 mm, width of compartment: 0.5 mm)

In a dry room, a stack-folding type electrode assembly having a bicell structure is housed in a cell casing so that electrode terminals of each electrode assembly are formed in one direction. After injecting a 1M LiPF ₆ carbonate electrolyte, 29 pouch-shaped unit cells were manufactured by thermally fusing the outer peripheral surfaces of the pouch-shaped unit cells.

Next, the module case, which is made of Al material, was disposed so that the inside of the module case was divided into 29 spaces, and the 29 unit cells were housed in each space so as to be in close contact with the cooling plate. At this time, the electrode terminals of the 29 unit cells were housed in the same direction so as to protrude from only one side of the battery module.

Next, one terminal assembly is manufactured so that the connection between the accommodated unit cells and the unit cells and the external terminals are performed at one time. In this case, terminal assemblies are provided with terminal holes into which electrode terminals of all the unit cells can be inserted. The electrode terminals of the inserted unit cells are connected in series through fastening of bus bars already formed in the terminal assemblies, Is also connected to an input / output terminal projected to the outside of the terminal assembly. Thereafter, the terminal assembly was connected to the portion where the electrode terminals were formed, and then the battery module was manufactured by welding the battery case with the case body to completely seal the module case.

( Comparative Example : Manufacture of Secondary Battery Module)

A battery module was fabricated in the same manner as in the above example, except that a plate-like aluminum cooling plate (thickness: 1.0 mm) was used in place of the cooling plate in the above-mentioned examples.

( Experimental Example : Penetration test)

The battery modules prepared in Examples and Comparative Examples were charged at a voltage of 4.2 V (CC-CV, 50 mA cut-off) at ½ C of the battery capacity, and then a steel bar having a semicircular cross section with a diameter of 3 mm bar) at a speed of 20 mm / s.

As a result of the tests, in the secondary battery modules of the examples and the comparative examples, the through holes in the cooling plate were formed. However, the diameter of the through-hole formed in the cooling plate of the embodiment was 3 mm, which was smaller than the diameter (4 mm) of the through-hole of the comparative example. In the unit cell adjacent to the cooling plate including the through- 3 in the case of the present invention, compared to the comparative example (4).

This result shows that, in the case of the cooling plate of the comparative example, since the nail penetration pressure advances in the penetrating direction (or vertical direction), the deformation of the cooling plate is transmitted to the adjacent unit cells in the same direction, As the empty space in the mesh spreads, the through pressure is transmitted horizontally to the adjacent meshes, and the adjacent meshes are deformed while absorbing the through pressure. As a result, the influence of the deformation of the cooling plate on the adjacent unit cells is reduced, so that the occurrence of short circuit is reduced.

In the foregoing detailed description of the present invention, specific examples have been described. However, various modifications are possible within the scope of the present invention. The technical idea of the present invention should not be limited to the embodiments of the present invention but should be determined by the equivalents of the claims and the claims.

10 secondary battery module
11 unit cell
20 cooling plate
21 Cooling section
21a opening
22b partition
22 reinforcing portion

Claims (21)

In the plate-type cooling plate,
A cooling section having a mesh structure penetrating in the thickness direction of the cooling plate is provided on the flat plate surface of the cooling plate,
Wherein the cooling portion includes a plurality of openings penetrating in the thickness direction of the cooling plate and a partition portion for partitioning between the openings,
Wherein the cooling section is formed of a mesh net in which wire-shaped wires are staggered in a lattice shape, the diameter of the wire is 0.1 mm to 1 mm,
Wherein the openings are formed in a hexagonal shape having the same size as each other, a distance a between two sides of the openings facing each other in parallel to each other is less than 10 mm,
Wherein the partition portion of the cooling portion is made of a material containing any one or two or more selected from the group consisting of aluminum, aluminum alloy, stainless steel, copper, silver and aluminum oxide,
Wherein the opening ratio of the cooling plate is 50% by volume to 90% by volume based on the total volume of the cooling plate.
delete delete delete delete delete delete The method according to claim 1,
A method of casting using a patterned mold so that the cooling section can form a mesh structure, a method of punching a flat plate for forming a cooling plate, a method of weaving using a wire-shaped wire material, And a method of inserting a structure having a mesh structure into a frame for forming a cooling plate having a storage space so that the cooling plate can be formed.
delete The method according to claim 1,
And a reinforcing portion is further provided so as to surround the upper portion of the cooling portion or the outer surface of the cooling portion.
11. The method of claim 10,
Wherein the reinforcing portion is made of one or more materials selected from the group consisting of aluminum, aluminum alloy, stainless steel, copper, silver and aluminum oxide.
delete The method according to claim 1,
Wherein the thickness of the cooling plate is 1 mm to 3 mm.
A secondary battery module in which a plurality of unit cells capable of charging and discharging are arranged at intervals,
The secondary battery module according to claim 1, wherein the cooling plate is interposed between the unit cells.
15. The method of claim 14,
And a cooling portion in the cooling plate has a size corresponding to the unit cell.
15. The method of claim 14,
A plurality of unit electrode assemblies in which the unit cells are stacked with a separator interposed therebetween, wherein a plurality of the unit electrode assemblies are stacked, the unit cells being stacked with a separator interposed therebetween, the separator comprising a positive electrode plate including a positive electrode active material coating portion on at least one surface thereof, and a negative electrode plate including a negative electrode active material coating portion, Wherein each of the overlapping portions includes a separation film, and the separation film includes a stack-folding type electrode assembly surrounding each unit electrode assembly.
15. The method of claim 14,
Wherein the unit cell includes electrode terminals positioned in one direction or both directions.
15. The method of claim 14,
Wherein the unit cells include electrode terminals electrically connected in series or in parallel at one or both sides of the secondary battery module.
A battery pack comprising the secondary battery module according to claim 14.
20. The method of claim 19,
A battery pack that is used as a power source for mid- to large-sized devices.
21. The method of claim 20,
Wherein the middle- or large-sized device is selected from the group consisting of an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle and a system for power storage.

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