[One]This application claims the benefit of priority based on Korean Patent Application No. 2019-0094564 dated August 02, 2019, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification.
[2]The present invention relates to a battery pack having a movable bus bar assembly and a secondary battery including the same, and more particularly, to a first bus bar frame positioned on the front part of the pack case, and a second bus bar frame positioned on the rear part of the pack case. At least one of the bus bar frame, the first bus bar connected to the first bus bar frame, and the second bus bar connected to the second bus bar frame is movable in the direction of the side plate of the pack case, so that the lead is short-circuited. To a battery pack having a movable bus bar assembly capable of minimizing
background
[3]
As technology development and demand for mobile devices such as cell phones, laptops, camcorders, and digital cameras increase, technologies related to rechargeable batteries that can be charged and discharged are becoming active. In addition, secondary batteries are applied to electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (P-HEVs), etc. as an alternative energy source for fossil fuels that cause air pollutants. The need for development is increasing day by day.
[4]
Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among them, lithium secondary batteries have little memory effect compared to nickel-based secondary batteries, so they can be charged and discharged freely. , the self-discharge rate is very low and the energy density is high.
[5]
This lithium secondary battery mainly uses a lithium-based oxide and a carbon material as a positive electrode active material and a negative electrode active material, respectively. It consists of an exterior material sealed and accommodated together with the electrolyte, that is, a battery case.
[6]
According to the shape of the battery case, the secondary battery is classified into a cylindrical battery and a prismatic battery in which the electrode assembly is embedded in a cylindrical or prismatic metal can, and a pouch-type battery in which the electrode assembly is embedded in a pouch-type case of an aluminum laminate sheet. can
[7]
A secondary battery used in a small device includes several battery cells, but a battery module electrically connecting a plurality of battery cells is used in automobiles. In such a battery module, a plurality of battery cells are connected to each other in series and parallel to improve capacity and output, and at this time, the battery module has a plurality of secondary batteries, that is, battery cells are stacked, and a bus bar for electrical connection between these battery cells. It is common to include a module (Busbar module). The bus bar module includes a bus bar for connecting electrode leads connected to each battery cell, and may be formed on one side of the battery module.
[8]
1 is a perspective view of a battery pack according to the prior art. As shown in FIG. 1 , a conventional battery pack includes at least two unit cells 10 including an electrode assembly 11 and a positive electrode lead 12 and a negative electrode lead protruding from both sides of the electrode assembly 11 . sub-modules arranged in parallel; a bus bar assembly 20 including a bus bar 22 electrically connected to leads of a sub-module and a bus bar frame 21 supporting the bus bar 22; and a pack case 30 for accommodating the sub-module and supporting the bus bar assembly 20 .
[9]
That is, a large number of batteries are connected as shown in FIG. 1 to satisfy high capacity such as electric vehicles and hybrid electric vehicles, and in this case, the leads are fixed to the bus bar 22 through welding, and the bus bar 22 is the bus bar. It has a structure that is fixed to the pack case 30 through the frame 21 .
[10]
On the other hand, battery swelling occurs in which the unit cells themselves swell due to various causes such as repeated charging and discharging, overcharging, and external shock, which causes adjacent unit cells to move toward the side plates 31 and 32 of the pack case. This can lead to a fire or explosion due to an internal short circuit, or expand beyond the allowable space in which the battery pack is installed, thereby compromising the safety of surrounding structures.
[11]
In more detail, in general, several, or at most, dozens of cell stacks are stacked side by side, and when each unit cell becomes thick during swelling, the cells located at the edge of the stack move to the side considerably from their original position. will be pushed out However, since the bus bar and the bus bar frame are fixed in their original positions, a large tension is generated in the lead connecting the unit cell and the bus bar, resulting in problems such as lead disconnection, and as a result, the performance of the unit cell and the battery pack. degradation occurs,
[12]
In order to solve the above problems, in Patent Document 1, by constructing an inverted U-shaped connecting piece between the support frame parts of a support member in which a plurality of bus bars are integrated by insert molding, a bus bar module capable of bending or deforming the connecting piece is provided. has been disclosed.
[13]
In Patent Document 2, a first terminal connection part composed of a conductive cone-shaped elastic body in contact with a terminal of a battery cell, and a second terminal connection part composed of a conductive cone-shaped elastic body contacting a terminal of another battery cell are located at a distance between the terminals. Disclosed is a busbar and a battery module spaced apart to match.
[14]
Patent Document 3 discloses a battery system that cuts off power supplied to a battery cell module when a swelling phenomenon due to overcharging occurs.
[15]
However, in Patent Documents 1 and 2, it is difficult to secure a sufficient moving distance due to the swelling of the battery, and in Patent Document 3, there is still a problem that the battery cannot be used even though the lifespan of the battery remains.
[16]
- Prior art literature -
[17]
- Patent literature
[18]
Japanese Laid-Open Patent Publication No. 2015-159024 (“Patent Document 1”)
[19]
Japanese Laid-Open Patent Publication No. 2016-219270 (“Patent Document 2”)
[20]
Republic of Korea Patent Publication No. 2014-0012264 ("Patent Document 3")
DETAILED DESCRIPTION OF THE INVENTION
technical challenge
[21]
In order to solve the above problems, in the present invention, even when a swelling phenomenon occurs, the load applied to the tabs, leads, and connections between the leads and busbars of the unit cells is reduced, and these tabs, leads and leads- An object of the present invention is to provide a battery pack capable of preventing damage to a bus bar connection and a secondary battery including the same.
[22]
In addition, in the present invention, a battery capable of preventing deterioration of battery performance due to malfunction of some unit cells, which occurs when the battery is used repeatedly such as charging and discharging, and swelling caused by natural phenomena, and furthermore, can prevent fire or explosion. An object of the present invention is to provide a pack and a secondary battery including the same.
means of solving the problem
[23]
The battery pack according to the present invention for solving the above problems is one or more unit cells ( 110) in which the sub-module 100 is disposed; A first bus bar frame 210 , a second bus bar frame 220 , and a first bus bar connected to the first bus bar frame 210 for connecting the sub-modules 100 in series or in parallel ( 230) and a bus bar assembly 200 including a second bus bar 240 connected to the second bus bar frame 220; and a first side plate 410 positioned side by side on one side of the sub-module 100 to support the bus bar assembly 200 while receiving the sub-module 100, and side by side with the other side of the sub-module 100 and a pack case 400 including a second side plate 420 positioned to be flush, and a bottom plate 430 positioned on the bottom of the sub-module 100, wherein the first bus bar frame 210, the second At least one of the bus bar frame 220 , the first bus bar 230 , and the second bus bar 240 is movable in the direction of the first side plate 410 and/or the second side plate 420 . characterized.
[24]
In addition, in the battery pack according to the present invention, the sub-module 100 is composed of N, which is a natural number equal to or greater than 3, in which two or more unit cells 110 are arranged in parallel, and the N sub-modules 100 are connected in series. In this way, the first bus bar frame 210 , the first bus bar 230 , and the two sub-modules 100 adjacent to each other after the N-2 th sub-module 100 are located on the front of the pack case 400 . ) is positioned on the rear side of the pack case 400, and the second bus bar frame 220 and the N-2th sub-module 100 are adjacent to each other. A second bus bar 240 connecting the modules 100 in series may be located.
[25]
In addition, in the battery pack according to the present invention, the sub-module 100 is composed of N, which is a natural number greater than or equal to 2, consisting of two unit cells 110 having a positive terminal and a negative terminal facing each other, and the unit cells 110 ) to be connected in series, the positive lead 112 and the negative lead 113 facing in one direction are respectively fixed to the plurality of first bus bars 230 spaced apart from each other by a predetermined distance, and the negative lead 113 of the other side. ) and the positive lead 112 may be fixed to the same second bus bar 240 .
[26]
In addition, in the battery pack according to the present invention, the sub-module 100 is composed of N, which is a natural number equal to or greater than 2, consisting of one unit cell 110 , and one side adjacent to the unit cells 110 can be connected in series. The positive lead 112 and the negative lead 113 are fixed to the first bus bar 230 , and the negative lead 113 and the positive lead 112 of the other side are fixed to the second bus bar 240 . can
[27]
In addition, in the battery pack according to the present invention, the first bus bar 230 and the second bus bar 240 are fixed to the first bus bar frame 210 and the second bus bar frame 220, respectively. Only the first busbar frame 210 and/or the second busbar frame 220 may be movable.
[28]
Also, in the battery pack of the present invention, a fixed shaft is provided between the first side plate 410 and the second side plate 420, and the first bus bar frame 210 and/or the second bus bar frame ( 220) may be formed with a first locking protrusion connected to the fixed shaft.
[29]
In addition, in the battery pack according to the present invention, a rail 431 is formed on the bottom plate 430 , and the rail 431 is formed on the first bus bar frame 210 and/or the second bus bar frame 220 . ) and a second blocking protrusion connected to may be formed.
[30]
In addition, in the battery pack according to the present invention, all of the first bus bar frame 210 , the second bus bar frame 220 , the first bus bar 230 and the second bus bar 240 are all independently of the first It may move in the direction of the side plate 410 and/or the second side plate 420 .
[31]
Also, in the battery pack according to the present invention, the first bus bar 230 and/or the second bus bar 240 may move.
[32]
In addition, in the battery pack according to the present invention, a first guide pole 213 is formed on the first bus bar frame 210 , and the first bus bar 230 accommodates the first guide pole 213 . A first hole 232 having a long hole shape may be formed.
[33]
Here, it is preferable that a first fastener 233 mounted on the first guide pole 213 is further provided.
[34]
In addition, in the battery pack according to the present invention, a second guide pole 223 is formed on the second bus bar frame 220 , and the second bus bar 240 receives the second guide pole 223 . A second hole 242 having a long hole shape may be formed.
[35]
In addition, the battery pack according to the present invention may further include a second fastener 242 mounted on the second guide pole 223 .
[36]
Also, in the battery pack according to the present invention, the connecting bus bar 250 may have a corrugated structure made of a conductive material.
[37]
In addition, in the battery pack according to the present invention, the connection bus bar 250 may be an elastic material made of a conductive material.
[38]
Also, in the battery pack according to the present invention, the connection bus bar 250 may have a coil shape.
[39]
Also, in the battery pack according to the present invention, the same number of slits as the unit cells 110 are formed in the first bus bar 230 and the second bus bar 240 , and the electrodes of each unit cell 110 are After passing through each slit, they may be fixed in different positions.
[40]
In addition, in the battery pack according to the present invention, fewer slits than the unit cells 110 are formed in the first bus bar 230 and the second bus bar 240 , and two or more electrodes are identical to the bus bar. It can be stacked and fixed sequentially at the points.
[41]
Also, in the battery pack according to the present invention, a cushion member 300 may be further provided between the sub-modules 100 .
[42]
In addition, in the present invention, it may be a secondary battery including a battery pack corresponding to any one of the above.
Brief description of the drawing
[43]
1 is a perspective view of a battery pack according to the prior art.
[44]
2 is a perspective view of a battery pack according to a first preferred embodiment of the present invention viewed from one side;
[45]
3 is a perspective view of the battery pack according to the first preferred embodiment of the present invention as viewed from the other direction.
[46]
FIG. 4 is a plan cross-sectional view of the battery pack shown in FIG. 2 .
[47]
FIG. 5 is an enlarged view of a dotted line portion in FIG. 2 , and is a perspective view illustrating a coupling structure between the bus bar frame and the bus bar.
[48]
6 is a perspective view illustrating a modified coupling structure between the bus bar frame of FIG. 5 and the bus bar.
[49]
FIG. 7 is a view for explaining a first modified example of the connection bus bar of FIG. 5 .
[50]
FIG. 8 is a view for explaining a second modified example of the connection bus bar of FIG. 5 .
[51]
9 is a perspective view of a battery pack according to a second preferred embodiment of the present invention viewed from one side.
[52]
10 is a perspective view of a battery pack according to a second preferred embodiment of the present invention as viewed from the other direction.
[53]
11 is an enlarged view of part A of FIG. 9 .
[54]
FIG. 12 is an enlarged view of part B of FIG. 9 .
[55]
13 is a cross-sectional view illustrating a coupling structure between a bus bar and an electrode lead in a battery pack according to a third preferred embodiment of the present invention.
[56]
14 is a cross-sectional view illustrating a coupling structure between a bus bar and an electrode lead in a battery pack according to a fourth preferred embodiment of the present invention.
[57]
15 is a cross-sectional view illustrating a coupling structure between a bus bar and an electrode lead in a battery pack according to a fifth exemplary embodiment of the present invention.
Modes for carrying out the invention
[58]
In the present application, terms such as "comprises", "have" or "comprises" are intended to designate that the features, numbers, steps, components, parts, or combinations thereof described in the specification exist, and are intended to indicate that one or more other It should be understood that this does not preclude the possibility of addition or presence of features or numbers, steps, operations, components, parts, or combinations thereof.
[59]
In addition, the same reference numerals are used throughout the drawings for parts having similar functions and functions. Throughout the specification, when it is said that a part is connected to another part, it includes not only a case in which it is directly connected, but also a case in which it is indirectly connected with another element interposed therebetween. In addition, the inclusion of a certain component does not exclude other components unless otherwise stated, but means that other components may be further included.
[60]
Hereinafter, a battery pack having a movable bus assembly according to the present invention and a secondary battery including the same will be described with reference to the accompanying drawings.
[61]
2 is a perspective view of a battery pack according to a first preferred embodiment of the present invention viewed from one side, FIG. 3 is a perspective view of a battery pack according to a first preferred embodiment of the present invention viewed from the other direction, and FIG. It is a plan sectional view of the battery pack shown in 2 .
[62]
2 to 4, the battery pack according to the first embodiment of the present invention includes a sub-module 100, a bus bar assembly 200, a cushion member 300, and a pack case 400. is done
[63]
First, the sub-module 100 is described. The sub-module 100 includes at least three or more units including the electrode assembly 111 and the positive electrode lead 112 and the negative electrode lead 113 on both sides of the electrode assembly 111 . Cells 110 are arranged in parallel.
[64]
On the other hand, the electrode assembly 111 is a jelly-roll type assembly having a structure in which a separator is interposed between a long sheet-shaped positive electrode and a negative electrode and then wound, or a rectangular positive electrode and a negative electrode are stacked with a separator interposed therebetween. A stack type assembly composed of unit cells, a stack-folding type assembly in which unit cells are wound by a long separation film, or a lamination-stack type assembly in which unit cells are stacked with a separation membrane interposed therebetween and attached to each other, etc. may be made, but is not limited thereto.
[65]
The electrode assembly as described above is embedded in a case, and the case is typically composed of a laminate sheet structure of an inner layer/metal layer/outer layer. Since the inner layer is in direct contact with the electrode assembly, it must have insulation and electrolyte resistance, and for sealing with the outside, the sealing property, that is, the sealing portion where the inner layers are thermally bonded to each other must have excellent thermal bonding strength. The material of the inner layer may be selected from polyolefin-based resins such as polypropylene, polyethylene, polyethylene acrylic acid, polybutylene, etc., polyurethane resins and polyimide resins having excellent chemical resistance and good sealing properties, but is not limited thereto, Polypropylene excellent in mechanical properties such as tensile strength, rigidity, surface hardness, and impact resistance and chemical resistance is most preferable.
[66]
The metal layer in contact with the inner layer corresponds to a barrier layer that prevents moisture or various gases from penetrating into the battery from the outside.
[67]
And an outer layer is provided on the other side of the metal layer, and this outer layer can be made of a heat-resistant polymer excellent in tensile strength, moisture permeability and air permeability to secure heat resistance and chemical resistance while protecting the electrode assembly, As an example, nylon or polyethylene terephthalate may be used, but is not limited thereto.
[68]
On the other hand, the leads composed of the positive electrode lead 112 and the negative electrode lead 113 may have a structure in which the positive tab and the negative tab of the electrode assembly are electrically connected to each other and then exposed to the outside of the case, and the leads without the positive tab and the negative tab may have a structure that directly connects the electrode assembly and the outside of the case, but is not limited thereto. Since the battery cells as described above correspond to generally known configurations, a detailed description thereof will be omitted.
[69]
The sub-module 100 includes an electrode assembly 111 and a plurality of unit cells 110 including electrode leads 112 and 113 extending from the electrode assembly 111 to match the capacity or output of the battery pack horizontally or vertically. It means that it is formed by stacking side by side in the direction. In FIGS. 2 and 3 , one sub-module 100 is illustrated as being composed of three unit cells 110 , but this is only an example and may be composed of two or more unit cells 110 . is self-evident
[70]
A plurality of sub-modules 100 as described above are again arranged side by side and then accommodated in the pack case 400 .
[71]
The bus bar assembly 200 is for fixing the unit cells 110 constituting the sub-module 100 to the pack case 400 while connecting them in series or in parallel, and includes one or more bus bar frames and one or more buses. bar and/or connecting busbar.
[72]
Specifically, in the case of FIG. 2 , which is the front part of the battery pack, a plurality of first bus bars 230 for connecting three unit cells 110 in parallel, and supporting and fixing the first bus bars 230 , are provided. A first bus bar frame 210 for
[73]
That is, the positive lead 112 or the negative lead 113 extending from the electrode assembly 111 of each unit cell 110 is bent through the first slit 231 of the first bus bar 230 , and then It is fixed to the outer surface of the first bus bar 230 through a known fixing method such as laser welding or resistance welding.
[74]
In addition, in order to connect the sub-modules 100 in series, a connecting bus bar 250 bent in a predetermined shape is provided between adjacent sub-modules 100 , and a positive lead 112 and a first bus bar 230 are provided. Similarly, the first bus bars 230 are connected to each other through a known fixing means.
[75]
On the other hand, the connection bus bar 250 is not located between the first first bus bar and the second first bus bar located on the leftmost side (the uppermost part in FIG. 2 ) of the battery pack 1 , which is the sub-module 100 . To connect them in series, they are electrically connected by the second bus bar 240 at the rear side of the battery pack.
[76]
3 , the rear surface of the battery pack according to the present invention has a plurality of second bus bars for serially connecting the unit cells 110 constituting the sub-module 100 in series. 240 and a second bus bar frame 220 for supporting and fixing these second bus bars 240 are positioned.
[77]
Accordingly, the unit cells 110 in one sub-module 100 are electrically connected in parallel, but each sub-module 100 is serially connected by the first bus bar 210 or the second bus bar 220 . It is a structure connected to (see FIG. 4).
[78]
A cushion member 300 having an elastic force may be included between the sub-module 100 and the sub-module 100 . The cushion member 300 is for preventing the short circuit of the leads in order to minimize the transmission of external pressure to the sub-module 100 located nearby when the specific unit cell 110 is swollen.
[79]
Subsequently, the pack case 400 serves to support the bus bar assembly 200 while accommodating the sub-modules 100 . The pack case 400 includes a first side plate 410 positioned side by side on one side of the sub-module 100, a second side plate 420 positioned side-by-side on the other side of the sub-module 100, and the bottom of the sub-module 100 . It is made to include a bottom plate 430 located in the.
[80]
The first side plate 410 , the second side plate 420 , and the bottom plate 430 may be assembled by a known fixing method such as an interference fit method, a bolt fastening method, or a welding method, and adhesiveness for each assembly part A sealing material may be further interposed.
[81]
On the other hand, even if the unit cells 110 are swollen by swelling, a pair of first fixed shafts on each of the front and rear parts to maintain the separation distance between the first side plate 410 and the second side plate 420 . A 440 and a second fixed shaft 450 may be additionally provided.
[82]
In the battery pack according to the present invention, at least one of the first bus bar frame 210 , the second bus bar frame 220 , the first bus bar 230 and the second bus bar 240 is a first side plate ( 410) and/or the second side plate 420 may be movable in the direction.
[83]
First, referring to FIGS. 5 to 8 , the first bus bar frame 210 and the second bus bar frame 220 are fixed to the pack case 400 while the first bus bar 230 and the second bus bar are fixed to the pack case 400 . A structure in which 240 is movable will be described.
[84]
FIG. 5 is an enlarged view of a dotted line portion in FIG. 2 , and is a perspective view illustrating a coupling structure between the bus bar frame and the bus bar.
[85]
The first bus bar 230 having a plurality of first slits 231 is provided with first holes 232 having one or more elongated holes in the upper and lower portions, respectively, and the first bus bar frame 210 The first guide pole 213 protruding from the ) is inserted into the first hole 232 . Here, the height of the first guide pole 213 is preferably slightly larger than the outer diameter of the first hole 232 so that the first guide pole 213 is guided to the first hole 232 to move left and right, In more detail, it may be 1 to 10 mm larger than the outer diameter of the first hole 232 .
[86]
Although illustrated as a long hole of a long oval in FIG. 5, it is obvious that it may have a long hole structure of various shapes, such as a rectangle.
[87]
On the other hand, a female screw thread is formed on the inner surface of the first guide pole 213 so that the first bus bar 230 can be detachably attached to the first bus bar frame 210 , and the female screw thread is to be fastened to the female screw thread. It is preferable that the first fastener 233 having an external thread formed on the outer surface of the cylinder is provided, and it is more preferable that the head is provided on one side of the cylinder so as to be a 'T' or 'L' shape.
[88]
Through the above configuration, when swelling of the electrode assembly 111 occurs, the entire first bus bar frame 210 can move a predetermined distance left and right along the first hole 232 , thereby minimizing the prevention of short circuit of the lead. In addition, there is an advantage that the first bus bar frame 210 and the first bus bar 230 are very easy to attach and detach.
[89]
6 is a perspective view illustrating a modified coupling structure between the bus bar frame of FIG. 5 and the bus bar. Only the first guide pole 213 and the first fastener 233 are different from the coupling structure shown in FIG. 5 , and the rest of the configuration is the same, so only these configurations will be described.
[90]
The first guide pole 213 and the first fastener 233 may be coupled to each other in a press-fitting manner. Specifically, the first guide pole 213 is in the shape of a square pillar with an empty inside, and the first fastener 233 is inserted into the insertion part and head of the square pillar so that it can be inserted inside the first guide pole 213 . can be done
[91]
Of course, it is self-evident that the cross-section of the insertion part of the first fastener 233 should be slightly larger than the inner cross-section of the first guide pole 213 so that the first fastener 233 is not too loose. However, it is obvious that it can be changed in various ways, such as a triangle, a pentagon, etc.
[92]
On the other hand, although a structure in which the first guide pole 213 is inserted into the first fastener 233 is also possible, the ease of assembly between the first guide pole 213 and the first fastener 233 and the first bus bar ( It is preferable that the first guide pawl 213 is inserted into the first fastener 233 so as not to interfere with the movement of the 230 .
[93]
FIG. 7 is a view for explaining a first modified example of the connection bus bar of FIG. 5 . Only the connection bus bar 250 is different from the coupling structure shown in FIG. 5 , but the rest of the configuration is the same. Therefore, only the connection bus bar 250 will be described.
[94]
The connecting bus bar 250 according to the first modified example may have a corrugated structure made of a conductive material. Even if the first bus bar 230 can move along the first guide pole 213 , it is difficult to secure a sufficient moving distance only with the cushioning force of the cushion member 300 and the connection bus bar 250 bent into a predetermined shape. However, when the connecting bus bar 250 having a corrugated structure is employed as in the first modified example, a longer moving distance can be secured, thereby preventing a short circuit of the lead. Here, the conductive material is not particularly limited as long as it can conduct electricity.
[95]
FIG. 8 is a view for explaining a second modified example of the connection bus bar of FIG. 5 . Only the connection bus bar 250 is different from the coupling structure shown in FIG. 5 , but the rest of the configuration is the same. Therefore, only the connection bus bar 250 will be described.
[96]
The connection bus bar 250 according to the second modification is not particularly limited as long as it is a stretchable conductive material, and has, for example, a corrugated structure and a coil shape. Here, in the case of a coil made of a conductive material, it may be a gold-silver nanocomposite, carbon nanotube, or carbon-rubber composite that is mixed with poly Styrene-Butadiene-Styrene (SBS) after wrapping the surface of conductive rubber and silver nanowires with gold.
[97]
Of course, it does not increase or decrease in length by itself, but the same purpose and function can be achieved by connecting the busbars somewhat loosely with flexible wires.
[98]
When the connecting bus bar 250 as in the second modified example is employed, there is an advantage that the first bus bar 230 can be moved with a small force as well as easy to secure a moving distance.
[99]
Although only the structure in which the first bus bar 230 is movable on the front side of the battery pack has been described with reference to FIGS. 5 to 8 , the second bus bar 240 adopts the same structure as the second bus bar ( 240) is self-evident.
[100]
9 to 12, the first bus bar 230 and the second bus bar 240 are respectively fixed to the first bus bar frame 210 and the second bus bar frame 220, A structure in which the first bus bar frame 210 and the second bus bar frame 220 are movable will be described.
[101]
9 is a perspective view of the battery pack according to a second preferred embodiment of the present invention viewed from one side, and FIG. 10 is a perspective view of the battery pack according to the second preferred embodiment of the present invention, viewed from the other direction.
[102]
2 and 3 , except for the configuration that the bus bar frame is provided with a locking protrusion and the bottom plate is provided with rails, everything else is the same as the battery pack according to the first embodiment of FIGS. 2 and 3 , so only these configurations will be described below. do.
[103]
In the battery pack according to the second preferred embodiment of the present invention, a first 'locking projection 211 is additionally provided on the upper portion of the first bus bar frame 210, and a second' locking projection 212 is formed on the lower portion of the first bus bar frame 210. has been
[104]
Referring to FIG. 11, which is an enlarged view of part A of FIG. 9, the first 'locking protrusion 211 will be described in more detail. It is formed on the first bus bar frame 210 , and the first ′ locking protrusion 211 is fastened to the first fixed shaft 440 .
[105]
Also, referring to FIG. 12, which is an enlarged view of part B of FIG. 9, a 'C'-shaped second 'locking protrusion 212 is formed under the first bus bar frame 210, and the second ' A rail 431 having a recessed portion is provided on the bottom plate 430 so that the locking protrusion 212 can be fastened thereto.
[106]
In summary, as shown in FIGS. 11 and 12 , the first 'locking protrusion 211 of the first bus bar frame 210 is the first fixing shaft 440 , and the second' locking protrusion 212 is the bottom plate 430 . ) by being fastened to the rail 431, respectively, it is possible to slide left and right.
[107]
Although detailed drawings and descriptions are omitted for the rear part of the battery pack according to the second embodiment, it is obvious that the locking protrusions and rails having the same structure as those of FIGS. 11 and 12 may be provided.
[108]
On the other hand, both of the first 'locking protrusions 211 and 2' locking protrusions 212 of the first bus bar frame 210 have a 'C'-shaped semi-ring shape, and these first' locking protrusions 211 and the second ' The locking protrusions 212 may be respectively coupled to the first fixed shaft 440 and the second fixed shaft 450 .
[109]
In addition, the first bus bar 230 and the second bus bar 240 are not fixed to each of the first bus bar frame 210 and the second bus bar frame 220 , but are not fixed to the first bus bar frame 210 and the second bus bar frame 220 described with reference to FIGS. 5 to 8 . A structure in which the first bus bar 230 and the second bus bar 240 are movable may be employed.
[110]
In this case, since the first bus bar frame 210 , the second bus bar frame 220 , the first bus bar 230 , and the second bus bar 240 can move independently, the electrode leads are short-circuited. can be most effectively prevented.
[111]
13 is a cross-sectional view illustrating a coupling structure between a bus bar and an electrode lead in a battery pack according to a third preferred embodiment of the present invention.
[112]
In the third embodiment of the present invention, bus bars having the same shape are connected to the front and rear portions of each sub-module, and leads constituting one sub-module may be overlapped and fixed to the bus bar.
[113]
Specifically, the cushion member 300 is positioned between the sub-modules composed of three unit cells, and the first bus bar 230 and the second bus bar 240 having the same number of slits as the lead are connected to the connecting bus bar ( 250), which is electrically connected to each other. In addition, the positive lead 112 or the negative lead 113 passing through each slit is fixed to overlap at the same position of each bus bar spaced apart from each other by a predetermined distance.
[114]
Of course, although not shown in the drawings, the number of slits of the bus bar may be smaller than the number of leads, and in this case, one or more leads may be fixed to overlap at the same position of the bus bar after passing through one slit.
[115]
By having the above structure, the size of the bus bar can be reduced, and it is easy to secure a space in which the bus bar can move.
[116]
13 is a cross-sectional view illustrating a coupling structure between a bus bar and an electrode lead in a battery pack according to a fourth preferred embodiment of the present invention.
[117]
In the fourth embodiment of the present invention, all unit cells are connected in series, and in one sub-module, in the unit cell, the positive terminal and the negative terminal are positioned to face each other. Specifically, the positive lead 112 and the negative lead 113 on one side facing the same direction are respectively fixed to the first bus bar 230 spaced apart by a predetermined distance, and these first bus bars 230 are It is electrically connected by a connecting bus bar 250 . Meanwhile, the negative lead 113 and the positive lead 112 on the other side are fixed to the same second bus bar 240 . And the cushion member 300 may be selectively positioned between each sub-module.
[118]
15 is a cross-sectional view illustrating a coupling structure between a bus bar and an electrode lead in a battery pack according to a fifth exemplary embodiment of the present invention.
[119]
As in the fourth embodiment, all unit cells are connected in series. However, in the fifth embodiment, the positive lead 112 and the negative lead 113 are respectively fixed to different first bus bars 230 or second bus bars 240 .
[120]
Specifically, the positive lead 112 and the negative lead 113 on one side facing the same direction are fixed to the first bus bar 230 spaced apart by a predetermined distance, and the negative lead 113 and the positive lead 112 on the other side. ) are also fixed to the second bus bars 240 spaced apart from each other by a predetermined distance. In addition, the first bus bars 230 and the second bus bars 240 are connected by a plurality of connection bus bars 250 .
[121]
On the other hand, although only the cross-sectional views of the bus bar and the electrode lead are shown in the third to fifth embodiments, the bus bar moving structure described in the first and second embodiments, the moving structure of the bus bus frame, the flexible connecting bus bar, etc. It is obvious that it can be applied.
[122]
As the specific part of the present invention has been described in detail above, for those of ordinary skill in the art, these specific descriptions are only preferred embodiments, and the scope of the present invention is not limited thereby, It is obvious to those skilled in the art that various changes and modifications can be made within the scope and spirit of the present invention, and it is natural that such variations and modifications fall within the scope of the appended claims.
[123]
- Explanation of symbols -
[124]
1: battery pack
[125]
100: submodule
[126]
110: unit cell
[127]
111: electrode assembly 112: positive lead
[128]
113: negative lead
[129]
200: bus bar assembly
[130]
210: first bus bar frame
[131]
211: 1' stumbling block 212: 2' stumbling block
[132]
213: first guide pole
[133]
220: second bus bar frame
[134]
221: 1″ stumbling block
[135]
230: first bus bar
[136]
231: first slit 232: first hole
[137]
233: first fastener
[138]
240: second bus bar
[139]
241: second slit
[140]
250: connecting busbar
[141]
300: no cushion
[142]
400: pack case
[143]
410: first side plate
[144]
420: second side plate
[145]
430: bottom plate
[146]
431: rail
[147]
440: first fixed shaft
[148]
450: second fixed shaft
Industrial Applicability
[149]
The battery pack according to the present invention has an advantage in that since the busbar and/or the busbar frame moves, damage to the tab, lead, and lead-busbar connection part of the unit cell can be prevented even when a swelling phenomenon occurs.
[150]
In addition, the battery pack according to the present invention can prevent damage to the tabs, leads, and lead-bus bar connections of the unit cells, thereby preventing deterioration of the performance of the entire battery pack and improving the stability of the battery.
[151]
In addition, the battery pack according to the present invention has the advantage of reducing waste by enabling the reuse of the battery along with the increase in the life of the battery.

WE CLAIMS

[Claim 1]a sub-module 100 in which one or more unit cells 110 including an electrode assembly 111, a positive electrode lead 112 and a negative electrode lead 113 on both sides of the electrode assembly 111 are disposed; A first bus bar frame 210 , a second bus bar frame 220 , and a first bus bar connected to the first bus bar frame 210 for connecting the sub-modules 100 in series or in parallel ( 230) and a bus bar assembly 200 including a second bus bar 240 connected to the second bus bar frame 220; and a first side plate 410 positioned side by side on one side of the sub-module 100 to support the bus bar assembly 200 while receiving the sub-module 100, and side by side with the other side of the sub-module 100 and a pack case 400 including a second side plate 420 positioned to be flush, and a bottom plate 430 positioned on the bottom of the sub-module 100, wherein the first bus bar frame 210, the second At least one of the bus bar frame 220 , the first bus bar 230 , and the second bus bar 240 is movable in the direction of the first side plate 410 and/or the second side plate 420 . Characterized by the battery pack.
[Claim 2]
According to claim 1, wherein the sub-module 100 is made of N, which is a natural number equal to or greater than 3 in which two or more unit cells 110 are arranged in parallel, so that the N sub-modules 100 can be connected in series; On the front surface of the pack case 400 , the first bus bar frame 210 , the first bus bar 230 , and two sub-modules 100 adjacent to each other after the N-2 th sub-module 100 are serially arranged. A connection bus bar 250 for connecting to the ) battery pack, characterized in that the second bus bar (240) for connecting in series is located.
[Claim 3]
According to claim 1, wherein the sub-module (100) is made of N, which is a natural number greater than or equal to 2, consisting of two unit cells (110) having a positive terminal and a negative terminal positioned to face each other, and the unit cells (110) in series The positive electrode lead 112 and the negative electrode lead 113 facing in one direction are respectively fixed to the plurality of first bus bars 230 spaced apart from each other by a predetermined distance, and the negative electrode lead 113 and the positive electrode of the other side are connected to each other. A battery pack, characterized in that the lead (112) is fixed to the same second bus bar (240).
[Claim 4]
According to claim 1, wherein the sub-module 100 is made of N, which is a natural number equal to or greater than 2 consisting of one unit cell 110, a positive lead on one side adjacent to connect the unit cells 110 in series 112 and the negative lead 113 are fixed to the first bus bar 230, and the negative lead 113 and the positive lead 112 of the other side adjacent to each other are fixed to the second bus bar 240 to the battery pack.
[Claim 5]
The first bus bar according to claim 1, wherein the first bus bar (230) and the second bus bar (240) are fixed to the first bus bar frame (210) and the second bus bar frame (220), respectively. A battery pack, characterized in that only the frame 210 and/or the second bus bar frame 220 is movable.
[Claim 6]
The method according to claim 5, wherein a fixed shaft is provided between the first side plate (410) and the second side plate (420), and the first bus bar frame (210) and/or the second bus bar frame (220) The battery pack, characterized in that the first locking projection connected to the fixed shaft is formed.
[Claim 7]
The rail (431) is formed on the bottom plate (430), and the first bus bar frame (210) and/or the second bus bar frame (220) is connected to the rail (431). A battery pack, characterized in that the second locking projection is formed.
[Claim 8]
According to claim 1, wherein the first busbar frame 210, the second busbar frame 220, the first busbar 230 and the second busbar 240 are all independently of the first side plate ( 410) and/or the battery pack, characterized in that it is movable in the direction of the second side plate (420).
[Claim 9]
The battery pack according to claim 1, wherein the first bus bar (230) and/or the second bus bar (240) are movable.
[Claim 10]
The method of claim 9, wherein a first guide pole (213) is formed on the first bus bar frame (210), and the first bus bar (230) has a long hole shape for accommodating the first guide pole (213). The battery pack, characterized in that the first hole (232) is formed.
[Claim 11]
The battery pack according to claim 10, further comprising a first fastener (233) mounted on the first guide pole (213).
[Claim 12]
11. The method of claim 10, The second bus bar frame (220) is formed with a second guide pole (223), the second bus bar (240) has a long hole shape for accommodating the second guide pole (223). The battery pack, characterized in that the second hole (242) is formed.
[Claim 13]
The battery pack according to claim 12, further comprising a second fastener (242) mounted on the second guide pole (223).
[Claim 14]
The battery pack according to claim 1, wherein the connecting bus bar (250) has a corrugated structure made of a conductive material.
[Claim 15]
The battery pack according to claim 1, wherein the connecting bus bar (250) is made of an elastic material of a conductive material.
[Claim 16]
The battery pack according to claim 15, wherein the connecting bus bar (250) has a coil shape.
[Claim 17]
The method according to claim 1, wherein the first bus bar (230) and the second bus bar (240) have the same number of slits as the unit cells (110), and the electrodes of each unit cell (110) form the respective slits. A battery pack, characterized in that it is fixed at different positions after being penetrated.
[Claim 18]
According to claim 1, wherein the first bus bar (230) and the second bus bar (240) is formed with fewer slits than the unit cell (110), two or more electrodes are sequentially disposed at the same point of the bus bar. A battery pack characterized in that it is laminated and fixed.
[Claim 19]
The battery pack according to claim 1, wherein a cushion member (300) is further provided between the sub-modules (100).
[Claim 20]
A secondary battery comprising the battery pack according to any one of claims 1 to 19.