KR101725911B1 - Unit Module Having Structure Being Possible to Connect Electrodes without Welding - Google Patents

Abstract

The present invention relates to a unit module having a structure in which at least one unit cell having two or more battery cells electrically connected to each other is mounted on an exterior member, the electrode terminals of the battery cells being each bent perpendicularly to an adjacent battery cell; Wherein the vertically bent surfaces of the electrode terminals are in surface contact with each other to form bending terminal portions of the unit cells; And a terminal connecting member which is closely attached to both sides of the bending terminal portion and mechanically fixed and electrically connected by pressing them.

Description

[0001] 1. Field of the Invention [0002] The present invention relates to a unit module having a structure capable of connecting electrode terminals without welding,

The present invention relates to a unit module having a structure capable of connecting electrode terminals without welding.

The rechargeable secondary battery is an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in electric vehicle (HEV) and the like, which are proposed as solutions for the air pollution of existing gasoline vehicles and diesel vehicles using fossil fuels Hybrid electric vehicles (Plug-In HEVs) and the like, and are attracting attention as a power source for devices requiring high output large capacity.

In such a device, a middle- or large-sized battery module in which a plurality of battery cells are electrically connected is used in order to provide a high output large capacity.

Since the middle- or large-sized battery module is preferably manufactured in a small size and weight, a prismatic battery, a pouch-shaped battery, or the like, which can be charged with a high degree of integration and has a small weight to capacity, is mainly used as a battery cell have. In particular, a pouch-shaped battery using an aluminum laminate sheet or the like as an exterior member has recently attracted a lot of attention due to its advantages such as small weight, low manufacturing cost, and easy shape deformation.

Fig. 1 schematically shows a perspective view of a typical conventional pouch-type battery. The pouch-shaped battery 10 shown in Fig. 1 has a structure in which two electrode terminals 11 and 12 protrude from the upper end and the lower end of the battery body 13, respectively. The pouch-shaped case 14 is formed by two upper and lower units. The pouch-type case 14 has two side surfaces 14a, an upper end portion 14b and a lower end portion 14b which are mutually contacted with each other with an electrode assembly (not shown) mounted on a receiving portion formed on the inner surface thereof. , 14c are attached to the battery 10 to make the battery 10.

The pouch type case 14 is made of a laminate structure of a resin layer / metal foil layer / resin layer so that heat and pressure are applied to the opposite side surfaces 14a and the upper and lower ends 14b and 14c which are in contact with each other, And may be adhered using an adhesive in some cases. Both side surfaces 14a are in direct contact with the same resin layer of the upper and lower pouch type case 14, so that they can be uniformly sealed by melting. On the other hand, since the electrode terminals 11 and 12 protrude from the upper end portion 14b and the lower end portion 14c, the sealing property can be improved in consideration of the thickness of the electrode terminals 11 and 12 and the heterogeneity with the material of the pouch- The electrode terminals 11 and 12 are thermally fused with a film sealing member 16 therebetween.

However, since the pouch type case 14 itself is not excellent in mechanical rigidity, in order to manufacture a battery module having a stable structure, generally, battery cells (unit cells) are mounted in a pack case such as a cartridge, . However, since a mounting space is limited in a device or a vehicle in which a middle- or large-sized battery module is mounted, when the size of the battery module is increased due to the use of a pack case such as a cartridge, a problem of low space utilization is caused. Further, the low mechanical rigidity of the battery cell is caused by the repeated expansion and contraction of the battery cell during charging and discharging, resulting in a case where the heat-welded portion is separated.

In addition, since the electrode terminals 11 and 12 of the pouch-shaped battery 10 are formed to have a relatively large area and a small thickness as compared with the electrode terminals of the cylindrical battery or prismatic battery, May be subject to restrictions.

Meanwhile, a battery module mounted on a middle- or large-sized battery pack is generally manufactured by stacking a plurality of battery cells at a high density, and electrically connects the electrode terminals of adjacent battery cells.

2 to 3 schematically show two battery cells electrically connected to each other at the electrode terminals.

2, the two pouch-shaped battery cells 10, 10 'are arranged in series in the longitudinal direction so as to continuously adjoin the electrode terminals 20 thereof, and the electrode terminals 11, 12 are welded to each other by laser or ultrasonic wave, and then the battery cells 10, 10 'are folded in two by two units. In FIG. 3, it can be seen that the electrode terminal connecting portion 20 welded by the battery cell stack 100 in the folded state is folded in a 'C' shape.

In the electrode terminal joining method by welding, electrode terminals welded to each other have a strong bonding force, but an initial cost for welding and a maintenance cost are incurred, a separate jig for welding is required, and a skilled technician It is disadvantageous in that the manufacturing and assembling process is complicated and the process cost is increased.

In addition, in the case of two battery cells having electrode terminals welded to each other, when any one of the battery cells is damaged or deteriorated in performance, it is impossible to replace or repair the battery cell alone, which makes maintenance difficult .

Accordingly, there is a great need for a technique capable of simple manufacture and assembly while solving the above problems.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

Specifically, it is an object of the present invention to provide a unit module of a compact structure while simplifying the process by mechanically fixing and electrically fixing the battery cells using a terminal connecting member capable of connecting electrode terminals without welding will be.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a unit module comprising: at least one unit cell having at least two battery cells electrically connected to each other;

The electrode terminals of the battery cells are each vertically bent toward the adjacent battery cells;

Wherein the vertically bent surfaces of the electrode terminals are in surface contact with each other to form bending terminal portions of the unit cells;

And a terminal connecting member that is mechanically fixed and electrically connected by pressing on both sides of the bending terminal portion.

That is, the unit module according to the present invention mechanically fixes and electrically connects the electrode terminals of the different battery cells through the terminal connecting member without welding, so that the welding process is not required in the manufacturing process of the unit module, , The manufacturing process of the unit module can be simplified, and when any one of the battery cells constituting the unit module is damaged or deteriorated, it is possible to replace or repair the battery cell after removing the terminal connecting member .

The terminal connecting member may be made of an electrically conductive material so as to facilitate electrical connection of the bending terminal portion and to enable electrical connection with other unit cells.

The electrically conductive material may be, for example, one or more metals selected from aluminum, copper or nickel, which is an electrically conductive metal, and may be an electrically conductive polymeric material containing carbon powder, but is not limited thereto.

In one specific example, the terminal connecting member includes: a first crimper inserted between the vertically-folded battery cells of the electrode terminals and closely attached to the first surface of the bending terminal portion;

A second clamp connected to the lower end of the first clamp by a hinge structure and pivotally rotating with respect to the hinge to come in close contact with the second face of the bend terminal; And

A third clamp connected to the upper end of the second clamp with a hinge structure and pivotally rotating with respect to the hinge to closely contact the second clamp;

As shown in FIG.

That is, the first crimp presses the first surface of the bending terminal portion and the second crimp presses the second surface, which is the opposing surface of the first surface, while bending the terminal portion of the unit cell between the first crimp and the second crimp .

Here, the third limb may include a ring-shaped lock member capable of rotating at an upper end or a lower end adjacent to a portion connected to the second limb.

In such a structure, the first limp and the second limp are received in the lock member after the lock member is rotated in a state in which the bending terminal portion is fixed between the first limp and the second limp, . Further, the locking member may be in the shape of a ring similar to the thickness of the first limp, the second limp and the third limp, and fixes the limp in the thickness direction.

In a concrete locking structure of the terminal connecting member according to the present invention, the bending terminal portion is inserted between the first limb and the second limb, the second limb pivots about the lower end of the first limb, And a bending terminal portion between the first terminal and the second terminal;

The third limb pivots about the upper end of the second limb in the direction opposite to the rotation direction of the second limb with the lock member of the third limb rotating and caught on the upper end of the first limb, And the terminal connecting member is tightly fixed to the outer surface to fix the bending terminal portion.

Therefore, the locking member mounted on the third limb can be fixed in such a manner that the limb is pressed against the first limb in the thickness direction of the first limb, the second limb and the third limb so that the limb can not rotate.

The locking member may have an inner diameter of 90% to 100% of the total thickness of the first, second, and third clips. If the inner diameter is less than 90% of the total thickness of the clamps, excessive force may be applied to the lock member during the lock process, and if it exceeds 100%, sufficient pressure is not applied to the clamps, which is not preferable .

In the above structure, the lock member is formed at the upper end or the lower end adjacent to the rotation axis of the third limb. When the lock member is engaged with the upper end of the first limb, the third limb, When the third limb is brought into close contact with the second limb by the rotation of the first limb in the direction of the third limb in a state in which the lock is fixed to the first limb, The first to third clips are fixed in a state of being closely contacted by the pressing force of the lock member.

Therefore, the first crimp, the second crimp, and the third crimp may be positioned parallel to each other with the terminal connecting member locked, wherein the first crimp, the second crimp, The first surface and the second surface.

Further, the second limb is provided with a locking groove for fixing the third limb when the third limb is closely contacted, and the third limb is provided with a locking portion for engaging with the locking groove at a position corresponding to the locking groove Lt; / RTI > And the engaging groove and the engaging portion may be engaged with each other in a female-male engaging structure.

This structure prevents the third crimp from coming off the second crimp due to an external force and releasing the locked state of the terminal connecting member when the third crimp comes into close contact with the outer surface of the second crimp and the terminal connecting member is in the locked state .

The first limb may include a surplus portion for catching the locking member even after the second limb member is in close contact with the first limb. The first limb may be longer than the second limb, The length may be 110% to 130% of the length of the climb.

Further, the first limb may be a structure that is attached to the outer member as the case may be, or may be a separately separated member.

The first crimp may have a length of 60% to 80% of the width of the unit cell in the direction in which the bent terminal portion is formed so that the first crimp is in contact with the first surface of the bending terminal portion, Lt; / RTI >

The third limb may have a length shorter than the length of the second limb, and more specifically, may have a length of 40% to 70% of the length of the second limb. When the length of the third crimp is shorter than the above range, a large external force is required for the rotation for locking. When the length is longer than the above range, the third crimp is easily released from the second crimp, Can be released.

In one specific example, the shape of the first crimp is not limited to a specific shape, but may be a structure in which the first crimp is in close contact with the first surface of the flat bent terminal portion. Specifically, the first crimp may have a rectangular parallelepiped structure Lt; / RTI >

Likewise, the shape of the third crimp may be in the form of a rectangular parallelepiped to be in close contact with the outer surface of the second crimp.

The second limb is a curved surface having an upper end connected to the third limb so as to correspond to the rotational motion of the third limb so that the third limb can smoothly rotate while the locking member is hooked on the upper end of the first limb. . On the other hand, the second limb may have a structure in which the lower end connected to the lower end of the first limb is formed in an angular shape, and the second limb is hard to rotate more than a certain angle in the opposite direction of the first limb. Therefore, the second crimp closely attached to the second surface of the bending terminal portion does not easily rotate in the direction opposite to the second surface, so that the bending terminal portion can be easily fixed between the first crimp and the second crimp.

The first crimper may have a width corresponding to the width between the electrode terminals constituting the bending terminal portion, and more specifically, may have a width of 100% with respect to the width between the electrode terminals.

When the width of the first crimp is less than 100%, it is not preferable that the first crimp can be released by the external force between the electrode terminals, thereby releasing the locking state of the terminal connecting member or making clear the bending terminal portions. , An excessive pressure may be applied between the electrode terminals to break the electrode terminals.

In one specific example, the type and structure of the battery cell are not particularly limited. For example, the battery cell may be a lithium secondary battery, and may be a plate-shaped battery cell having a wider width than a rectangular shape.

The plate-shaped battery cell may be a pouch-shaped battery cell having a structure in which an outer circumferential surface of a cell case is sealed with an electrode assembly embedded in a cell case of a laminate sheet including a resin layer and a metal layer.

Specifically, the plate-shaped battery cell is a pouch-shaped battery cell in which an electrode assembly having an anode, a separator, and a cathode structure is sealed inside a battery case together with an electrolyte. The battery cell is a plate-shaped battery cell having a substantially rectangular parallelepiped structure. Such a pouch-shaped battery cell is generally composed of a battery case of a pouch type, and the battery case is composed of an outer coating layer made of a polymer resin having excellent durability; A barrier layer made of a metal material exhibiting barrier properties against moisture, air, and the like; And an inner sealant layer composed of a polymer resin that can be thermally fused, are laminated in this order.

The case of the pouch type battery cell may have a variety of structures. As an example of the structure, the electrode assembly may be housed in a housing part formed on the upper and / or lower inner surfaces as two units, And the upper and lower contact portions of the upper and lower portions are thermally fused and sealed.

In the battery cell, the electrode terminals may be formed at the upper and lower ends of the battery cell, respectively. Specifically, the battery cell may have a structure in which a positive terminal protrudes from one side of the outer circumferential surface and a negative terminal protrudes from the opposite side.

Meanwhile, in one specific example, the outer member has an inner surface structure corresponding to the outer shape of the unit cell, and in particular, a first cover and a second cover, which are assembled by an assembling method, .

When the first cover and the second cover are pressed in contact with each other so as to face each other, a fastening protrusion and a fastening groove are formed in the first cover and the second cover, respectively, so that the sheath can be engaged by elastic coupling And they may be bonded to each other.

Also, the exterior member may have a structure in which the second cover encircles the entire one side end portion of the unit cell, a part of the upper end and the lower end portion, and the first cover surrounds the entire other side end portion and the remaining portions of the upper and lower ends .

The present invention also provides a battery module including at least one unit module, and uses the battery module as a power source.

The device may be any one selected from the group consisting of, for example, a mobile phone, a tablet computer, a notebook computer, a power tool, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, and a power storage device, It is not.

Since the structure of such devices is well known in the art, a detailed description thereof will be omitted herein.

As described above, the unit module according to the present invention mechanically fixes and electrically connects the electrode terminals of different battery cells through the terminal connecting member without welding, so that no welding process is required in the manufacturing process of the unit module Accordingly, the manufacturing process of the unit module can be simplified, and if any one of the battery cells constituting the unit module is damaged or deteriorated, the terminal connecting member is removed, and the battery cell is replaced or repaired .

1 is a schematic view of a battery cell according to the prior art;
FIG. 2 is a schematic view showing a structure in which two electrode terminals of the battery cell of FIG. 1 are welded together; FIG.
3 is a schematic view of the unit cell manufactured in FIG. 2;
4 is a perspective view of the terminal connecting member according to the present invention;
5 is a side schematic view of the terminal connecting member shown in Fig. 4;
6 is a side view schematically showing a first crimp and a second crimp in close contact with each other in the terminal connecting member shown in Fig. 5;
7 is a side view schematically showing the terminal connecting member shown in Fig. 6 in a state in which the locking is completed;
8 is a schematic view of a unit cell according to the present invention;
9 is a schematic diagram of a unit module according to an embodiment of the present invention;
10 is an enlarged view of a portion A in Fig. 9; Fig.
11 is a perspective view showing the movement of the locking member in Fig. 10;
12 is a perspective view showing a state in which the terminal connecting member shown in Fig. 11 is completely locked.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited by the scope of the present invention.

Fig. 4 is a perspective view of the terminal connecting member according to the present invention, Fig. 5 is a schematic side view of the terminal connecting member shown in Fig. 4, and Fig. 6 is a cross- FIG. 7 schematically shows a side surface of the terminal connecting member shown in FIG. 6 in which the locking is completed. FIG. 7 is a side view showing a state in which the first crimper and the second crimp come into close contact with each other.

4 and 5, the terminal connecting member 200 is composed of a first limb 202, a second limb 204, a third limb 206, and a lock member 208.

The first climb 202 has a hexagonal structure extending from the first climb 202, the second climb 204 and the third climb 206 to the longest rectangular shape,

The second crimp 204 has a length of approximately 70% with respect to the first crimp 202 and has a curved surface at the upper end, a lower end in an angled bar shape, and a lower end of the second crimp 204 Is hinged by a hinge (203) to a portion adjacent to the lower end of the first limb (202) and can be pivotally rotated about the hinge (203).

The third limb 206 is connected by a hinge 205 to a portion of the upper end of the third limb 206 adjacent to the upper end of the second limb 204 on which the curved surface is formed and can pivot about the hinge 205 .

The third limb 206 has a ring-shaped lock member 208 rotatably mounted on the upper end of the hinge 205 connected to the second limb 204.

A locking groove 209 is formed in the outer surface of the second limb 204 facing the third limb 206 so as to be engageable with the male limb 204. A third limb 206 facing the second limb 204, A fastening protrusion 210 for engaging with the fastening groove 209 of the second clamp 204 is formed at a position corresponding to the groove 209. [

Figs. 6 and 7 schematically show a process in which the clamps of the terminal connecting members of Figs. 4 and 5 are pivoted to be in a locked state. The second limb 204 is pivotally rotated about the hinge 203 at the lower end of the first limb 202 so as to be horizontal with the first limb 202, Tightly. The lock member 208 formed on the third limb 206 is pivoted in the direction of the first limb 202 and hooked on the top of the first limb 202. [

At this time, since the position of the lock member 208 mounted on the third limb 206 is located adjacent to the first limb 202, the first limb 202 is not pressed.

7, the third limb 206 is pivotally rotated about the hinge 205 at the upper end of the second limb 204 so as to be horizontal with the second limb 204, so that the second limb (204) The position of the lock member 208 mounted on the third limb 206 is moved away from the first limb 202 so that the upper end of the first limb 202 is moved away from the second limb 202, The second limp 204 between the first limb 202 and the third limb 206 is pressed against the lock member 208 when the third limb 206 stops rotating, And the upper end of the first limb 202 to which the lock member 208 is hooked. Thus, the second limb 204 can not pivot and the second limb 204 is urged in the direction of the first limb 202. In addition, the engagement protrusion 210 formed on the third limb 206 is engaged with the engagement groove 210 formed on the second limb 204 to prevent unnecessary pivotal rotation of the third limb 206, The second climb 204 and the third climb 206 are parallel to each other and the terminal connecting member 200 (200) is held in a state where the pressure is maintained between the first climb 202 and the second climb 204, Is in a locked state.

FIG. 8 schematically shows a unit cell 300 according to the present invention. 8, the unit cell 300 includes two battery cells 50 and 60. The electrode terminals of the battery cells 50 and 60 are bent perpendicularly to the adjacent battery cells, The bending terminal portions 310 are formed so that the bent surfaces of the electrode terminals are overlapped with each other. At this time, the bending terminal portion 310 includes the first surface 312 facing the battery cells 50 and 60 and the second surface 314 facing the opposite direction.

8 shows that the unit cell 300 includes only two battery cells and the electrode terminal forms a bending terminal portion at both ends of the unit cell 300. However, , And the electrode terminal may be bent as shown in FIG. 3, so that a unit cell including three or more battery cells is also possible.

Fig. 9 schematically shows a unit module according to the present invention, and Fig. 10 is a schematic diagram showing an enlarged view of a portion A in Fig. 11 and 12 sequentially show the movement of the locking member 208 of Fig.

For reference, only a part of the exterior member is shown in FIG. 9 for convenience of explanation, but it goes without saying that the exterior member to which the pair of the covers are coupled is also included in the scope of the present invention.

Referring to FIGS. 4 and 8, the unit module 400 includes a unit cell 300, a terminal connecting member 200, and an armoring member 350.

The first crimping 202 of the terminal connecting member 200 is in close contact with the first surface 312 of the bending terminal portion 310 while the electrode terminals are inserted between the vertically bent battery cells 50 and 60 . 8, the second crimp 204 is pivotally rotated about the hinge 203 at the lower end of the first crimp 202 so as to be horizontal with the first crimp 202, As shown in FIG. The lock member 208 formed on the third limb 206 is pivoted in the direction of the first limb 202 and hooked on the top of the first limb 202. [

The third limb 206 is pivotally rotated about the hinge 205 at the upper end of the second limb 204 so as to be horizontal with the second limb 204 so as to be brought into close contact with the outer surface of the second limb 204 The terminal connecting member 200 presses and fixes the first surface 312 and the second surface 314 of the bending terminal portion 310 between the first crimp 202 and the second crimp 204 Thereby achieving their electrical connection.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Claims (22)

A unit module having a structure in which at least one unit cell in which two or more battery cells are electrically connected is mounted on an exterior member,
The electrode terminals of the battery cells are each vertically bent toward the adjacent battery cells;
Wherein the vertically bent surfaces of the electrode terminals are in surface contact with each other to form bending terminal portions of the unit cells;
And a terminal connecting member which is mechanically fixed and electrically connected by pressing on both surfaces of the bending terminal portion,
The terminal connecting member
A first crimper inserted between the vertically bent battery cells and the first terminal of the bending terminal portion;
A second clamp connected to the lower end of the first clamp by a hinge structure and pivotally rotating with respect to the hinge to come in close contact with the second face of the bend terminal; And
A third clamp connected to the upper end of the second clamp with a hinge structure and pivotally rotating with respect to the hinge to closely contact the second clamp;
And a unit module. delete The unit module according to claim 1, wherein the third limb includes a ring-shaped lock member rotatable at an upper end or a lower end adjacent to a portion connected to the second limb. [2] The apparatus of claim 1, wherein the first limb has a length of 110% to 130% of the length of the second limb, and the third limb has a length of 40% to 70% of the length of the second limb. Unit module. 2. The unit module according to claim 1, wherein the first and third clamps have a rectangular parallelepiped structure. 2. The unit module according to claim 1, wherein the second limb is curved so that the upper end to which the third limb is connected corresponds to the rotation motion of the third limb. The unit module according to claim 3, wherein the locking member has an inner diameter of 90% to 100% of a total thickness of the first, second, and third clips. 4. The apparatus according to claim 1 or 3, wherein the bending terminal portion is inserted between the first limb and the second limb, the second limb pivots about the lower end of the first limb, and the first limb and the second limb The bending terminal portion between the bending terminal portions is pressed;
The third limb pivots about the upper end of the second limb in the direction opposite to the rotation direction of the second limb with the lock member of the third limb rotating and caught on the upper end of the first limb, And the terminal connecting member is brought into close contact with the outer surface to lock the bending terminal portion. The unit module according to claim 8, wherein the first crimp, the second crimp, and the third crimp are parallel to each other with the terminal connecting member locked. 9. The apparatus according to claim 8, wherein the second plunger is provided with a coupling groove for fixing the third plunger when the third plunger is closely contacted, and the third plunger is provided at a position corresponding to the coupling groove And a fastening portion is formed on the lower surface of the unit module. The unit module according to claim 10, wherein the engaging groove and the engaging portion are engaged with each other in a female-male engaging structure. The unit module according to claim 1, wherein the first crimp has a width of 100% of a width between the electrode terminals. The unit module according to claim 1, wherein the bending terminal portion is made of an electrically conductive material. The unit module according to claim 1, wherein the battery cell is a rectangular plate-shaped battery cell. 15. The battery module according to claim 14, wherein the plate-shaped battery cell is a pouch-shaped battery cell having a structure in which an outer periphery of a cell case is thermally fused and sealed while an electrode assembly is housed in a cell case of a laminate sheet including a resin layer and a metal layer A unit module. The unit module according to claim 1, wherein the exterior member has an inner surface structure corresponding to an outer shape of the unit cell, and includes a first cover and a second cover which are coupled to each other in an assembling manner. [17] The apparatus according to claim 16, wherein the cover member is fastened to the first cover and the second cover by a fastening protrusion and a fastening protrusion, respectively, so that the first cover and the second cover can be engaged by resilient engagement when pressed in contact with each other, And a groove is formed in the groove, and the groove is engaged with the groove. 17. The battery pack as claimed in claim 16, wherein the casing member surrounds the entire one side end portion of the unit cell and a portion of the upper and lower ends of the unit cell, and the first cover surrounds the entire other side end portion and the remaining portions of the upper and lower ends And a unit module. The unit module according to claim 1, wherein the electrode terminals are formed at an upper end and a lower end of the battery cell, respectively. A battery module comprising at least one unit module according to claim 1. A device using the battery module according to claim 20 as a power source. 22. The device of claim 21, wherein the device is any one selected from the group consisting of a cell phone, a tablet computer, a notebook computer, a power tool, an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, Device.

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