KR20110105945A - Secondary electric cell with cooling structure - Google Patents

Abstract

The parallel type secondary battery including the cooling structure according to the present invention includes a plurality of battery cells facing each other including an electrode assembly having a positive electrode and a negative electrode formed therein and a pouch for accommodating the electrode assembly; A relay electrically connecting the positive and negative electrodes of the plurality of battery cells so that the plurality of battery cells are connected in parallel; And a cooling plate interposed between the plurality of battery cells facing each other.
According to the present invention, it is possible to provide a secondary battery and a battery system using the same, which can be easily extended to a battery environment in which a large capacity is required, as well as efficient heat dissipation according to the large capacity battery.

Description

Secondary electric cell with cooling structure {Secondary electric cell with cooling structure}

The present invention relates to a secondary battery electrically connected in parallel, and more particularly to a secondary battery including a cooling structure for heat dissipation between a plurality of secondary battery cells in order to implement a high capacity secondary battery more efficiently.

The secondary battery has high applicationability and high electrical density such as electric power, and is widely used for electric vehicles (EVs) or hybrid vehicles (HVs) driven by electric driving sources as well as portable devices. It is applied.

The secondary battery is attracting attention as a new energy source for improving eco-friendliness and energy efficiency in that not only the primary advantage of significantly reducing the use of fossil fuels is generated, but also no by-products of energy use are generated.

The secondary battery (cell) may be classified into various types such as pouch type, can type, small size, medium and large type according to the type, structure and application form of the exterior. Since the basic principle and configuration may correspond to each other, the schematic structure of the secondary battery will be described by using the pouch-type secondary battery illustrated in FIGS. 1 and 2 as an exemplary form.

As illustrated in FIG. 1, the pouch-type secondary battery 10 includes a pouch 20 and an electrode current collector 30 (also referred to as an electrode assembly), which is a case exterior material, as a basic structure. 30 includes a positive electrode plate, a negative electrode plate, and a separator or separator interposed between the positive electrode plate and the negative electrode plate to electrically insulate the positive electrode plate and the negative electrode plate.

As shown in FIG. 1, the electrode current collector 30 generally includes a positive electrode lead (tab) 31 extending from the positive electrode plate and a negative electrode lead (tab) 30 extending from the negative electrode plate. The electrode leads 31 and 32 correspond to a structure that functions as an electrode of a secondary battery, and a carbon-based material and a lithium-based oxide are used for the anode, and an organic solvent electrolyte is mainly used for the electrolyte.

After the electrode current collector 30 is introduced into the pouch case 200, an electrolyte solution is injected, and then, a post-treatment process such as a sealing process, an aging process, a chemical conversion process, and the like is a completed secondary battery cell.

The secondary battery is referred to as a unit cell (cell), an assembly assembly (assembly), a battery (pack), etc. according to the configuration order of the individual, and unless otherwise stated in the following description, the present description The secondary battery in Essence is to be used generically without distinguishing the individual.

FIG. 1 illustrates an embodiment in which the pouch case 20 is dualized into the upper case 21 and the lower case 22, and a space in which the electrode current collector 30 is provided is formed in only one case. 2 is relatively divided into an upper case 21 and a lower case 22 by using one pouch case 20, and the space in which the electrode current collector 30 is provided is formed in both cases. It is shown.

Whether the case is physically dualized or the space in which the electrode current collector is provided is apparent to those skilled in the art through various combinations and modifications according to pouch raw materials, product characteristics, processing environments, and product specifications.

The secondary battery manufactured as described above has a problem in that its capacity cannot be manufactured simply by physically increasing its capacity due to the inherent and inherent electrochemical characteristics of the secondary battery. That is, when manufactured with a unit cell of 25 Ah or more, the draw width of the pouch packaging material is increased due to the increase in the thickness of the cell, thereby increasing the possibility of defects.

In addition, the pouch sheathing material is used for the purpose of physical protection means for preventing the leakage of electrolyte inside the battery, etc. If the stretch width is increased in this way, the pouch sheathing material itself may be defective, resulting in electrolyte leakage and electrical short circuit. May be exposed to secondary risks.

In addition, when the unit cell is manufactured by simply increasing the physical size, the wetting efficiency of the electrolyte to the electrode current collector may be degraded, leading to premature deterioration of the cell performance. A rapid increase in the amount of heat generated may result in deterioration of electrical characteristics due to high temperature, thereby accelerating degeneration of the cell.

In addition, when the cells are simply electrically connected, there is a problem that the connected cells may be malfunctioned in series due to such external factors when exposed to physical adverse conditions such as external lances, penetration, or pressurization. May be a fatal risk factor for the molten object (EV, HEV) and the user operating the same.

The present invention has been made to solve this problem in the background as described above, in implementing a high-capacity secondary battery connected in parallel, to improve the performance degradation due to heat generation, and to robust to water inflow, electrolyte outflow and external physical factors The purpose is to provide a secondary battery that can cope.

Other objects and advantages of the invention will be described below and will be appreciated by the embodiments of the invention. In addition, the objects and advantages of the present invention can be realized by the configuration and combination of configurations shown in the claims.

A parallel type secondary battery including a cooling structure of the present invention for realizing the above object comprises a plurality of battery cells facing each other including an electrode assembly having a positive electrode and a negative electrode formed therein and a pouch for accommodating the electrode assembly; A relay electrically connecting the positive and negative electrodes of the plurality of battery cells so that the plurality of battery cells are connected in parallel; And a cooling plate interposed between the plurality of battery cells facing each other.

Herein, the plurality of battery cells may be configured such that each electrode assembly is continuously provided in one common pouch, and the pouch portions between the electrode assemblies are folded to face each other.

In order to implement a more preferred embodiment, the cooling plate may be composed of a metal plate, it is preferable to configure the size corresponding to the size of the electrode assembly, the metal plate may be composed of an aluminum material. The cooling plate is preferably composed of a plurality of divided metal plate.

In addition, the cooling plate may be provided with a buffer member of the elastic material on the outer peripheral surface, the buffer member is preferably provided so that a plurality of unit objects are spaced apart from each other on the surface of the cooling plate.

The parallel type secondary battery including the cooling structure according to the present invention can be effectively implemented as a secondary battery having a high capacity, and can effectively overcome the thermal efficiency problem due to parallel connection of unit cells, thereby further improving performance and easy expansion. It is possible to implement a secondary battery and a battery system using the same.

In addition, the sealing area of the pouch secondary battery can be reduced inherently, thereby minimizing moisture infiltration from outside, leakage of electrolyte, etc., and also being applied from the outside such as lances, penetrations, impacts, etc. through the physical structure of the cooling plate. Minimized damage due to physical factors can provide a more stable secondary battery.

In addition, it is possible to effectively release the heat generated by the operation of the high-capacity secondary battery and its additional expansion battery, and to prevent the interference between the secondary batteries, thereby reducing or delaying the heat generation of the secondary battery even in the state of overcharge or overdischarge. The explosion of the secondary battery due to heat generation can be effectively prevented.

In addition, it is possible to effectively eliminate the inefficiency caused by the performance degradation, early deterioration of the high-capacity secondary battery, it is possible to create an effect that can provide a secondary battery that can be more economical and secure a competitive price for the product.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate preferred embodiments of the invention and, together with the description of the invention given below, serve to further the understanding of the technical idea of the invention. And should not be construed as limiting.
1 is a view illustrating a general state of manufacturing a secondary battery unit cell;
2 is a diagram illustrating a general state of manufacturing a secondary battery unit cell according to another embodiment;
3 is an exploded perspective view showing the configuration of a secondary battery according to an embodiment of the present invention;
4 is a view showing a coupling relationship of a secondary battery according to an embodiment of the present invention;
5 is a perspective view showing an outer shape of a secondary battery according to an embodiment of the present invention;
6 is a view showing a coupling relationship of a secondary battery according to another embodiment of the present invention;
7 is a view showing the configuration of a cooling plate according to a preferred embodiment of the present invention;
8 is a view showing the configuration of a cooling plate according to another embodiment of the present invention,
9 is a view showing the configuration of a cooling plate according to another preferred embodiment of the present invention,
10 is a view illustrating a coupling relationship of a secondary battery in which a plurality of battery cells are collected according to another embodiment of the present invention;
FIG. 11 illustrates a plan view of a secondary battery in which the coupling of FIG. 10 is completed.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the present specification and claims should not be construed as being limited to the common or dictionary meanings, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

3 is a view showing the configuration of a secondary battery according to an embodiment of the present invention. As shown in FIG. 3, the parallel type secondary battery (hereinafter referred to as a secondary battery) 100 including the cooling structure according to the present invention has a structure in which a plurality of battery cells 110 and 120 are connected in parallel to each other. .

As described above, in order to overcome the problems of the prior art, the secondary battery 100 of the present invention first includes a plurality of cells 110 and 120 when mounted in the pouch 200 that performs the exterior function of the battery cell. It is mounted together in a plurality of mounting spaces 210 provided in the pouch. As mentioned above, each of the unit battery cells 110 and 120 includes the positive electrode 310, the negative electrode 320, and the electrode assembly 300.

The detailed configuration of the cell is not a core technical idea of the present invention, and a detailed description thereof will be omitted since it is well known among those skilled in the art, and the form of a cell mounting space inside the pouch shown in FIG. 3 and the number of cells to be mounted. And the like only illustrate one exemplary form, and various modifications and applications are possible to those skilled in the art.

As shown in FIG. 3, when a plurality of battery cells 110 and 120 are mounted in one common pouch 200, electrolyte is injected as described above, and post-treatment such as a sealing process, an aging process, and a chemical conversion process is performed. The process may proceed by various combinations or process sequences as needed.

As shown in FIG. 3, the plurality of battery cells 110 and 120 are mounted or mounted together in one common pouch 200, thereby minimizing a phenomenon such as water penetration and leakage of electrolyte, and of course, individual Since the process of connecting the unit cells can be omitted, more efficient secondary batteries can be manufactured.

When the mounting process of the plurality of battery cells is completed as shown in FIG. 4, between the pouch regions in which the electrode assemblies of the plurality of battery cells 110 and 120 are mounted (part A of FIGS. 3 and 4). By folding the pouch 200 as a reference to be configured to face each other.

3 and 4, the secondary battery of the present invention is to connect a plurality of battery cells so as to be electrically parallel to each other mounted on a pouch so that the electrodes of each battery cell to face each other to interconnect the electrodes It is preferable to comprise so that the process to be easy may be carried out.

In addition, in this process, as illustrated in FIG. 4, the plurality of battery cells are interposed between the plurality of battery cells 110 and 120 facing each other via a cooling plate 400 that performs a heat dissipation function.

3 to 5 is one embodiment according to the present invention, as shown in Figure 6 can be configured to be folded (folding) the upper and lower surfaces of the pouch according to the embodiment.

As briefly mentioned above, in the case of implementing a high capacity to large capacity secondary battery by overlapping a plurality of unit battery cells in a stack form in a horizontal to vertical direction and electrically connecting them in parallel, heat dissipation is greatly increased by an electrochemical reaction. Will be.

The cooling plate 400 is interposed between the plurality of battery cells 110 and 120 as described above in order to effectively remove the heat dissipation and guarantee or maintain the normal performance of the secondary battery.

In consideration of the embodiment of the secondary battery, since the overall thickness factor of the secondary battery is important, the cooling plate 400 is more preferably embodied in a plate shape as illustrated in FIG. 4. In consideration of the above, it is preferable to configure a metal plate, and the cooling plate 400 may employ various metals having a specific heat transfer rate that may be determined according to specifications, application environments, and the like of the secondary battery to be manufactured. Among them, it is preferable to configure the aluminum material having high heat dissipation efficiency and high forming flexibility such as ease of processing into a slice plate shape.

On the other hand, since the heat generated by the charging and discharging of the secondary battery is mostly made in the electrode current collector region that reacts with the injected electrolyte electrochemically, the cooling plate 400 is the electrode assembly ( It is more preferable to form the size corresponding to the size of 300).

The configuration to correspond to the size of the electrode assembly 300 is to improve the heat dissipation intensive region and the heat dissipation efficiency thereof, as mentioned above, means a corresponding size of the actual size in consideration of the error range, physical or Obviously, it does not mean size equality in a mathematical sense.

As such, when the cooling plate 400 is formed of a metal plate, an effect of robustly protecting the inner secondary battery cell may be created even against physical price from the outside such as lanceolating or penetrating.

In addition, the cooling plate 400 may be composed of one integral metal plate, as well as to increase the degree of recycling in the case of partial damage or breakdown in the future and to smoothly flow in the air medium to improve thermal efficiency in FIG. As shown, it may be composed of two or more plates (401, 402, 403). In order to improve work efficiency, the shape divided in the vertical direction rather than the horizontal direction is preferable.

Meanwhile, in order to implement a more preferred embodiment of the present invention, as shown in FIG. 8, the cooling plate 400 interposed between the plurality of battery cells 110 and 120 is a base plate (substrate) made of a metal material as a base ( 410 and the buffer member 420 of the elastic material on the outer peripheral surface thereof.

The secondary battery has a property of repeating charging and discharging by an electrochemical reaction. In this process, a swelling phenomenon (swelling) may occur. In addition to this, a phenomenon such as movement, shaking or vibration of the physical position of the secondary battery cell occurs due to external impact or pressure.

By providing a shock absorbing member 420 having an elastic force on the outer circumferential surface of the cooling plate 400 as described above, such external factors can be effectively absorbed, so that the secondary battery and the battery or battery system using the unit as a unit can be more stably and safely operated. can do.

In addition, according to the embodiment, as shown in FIG. 9, the buffer member 420 may be configured as a plurality of unit objects, and may be provided to be spaced apart from each other on the surface of at least one surface of the base plate 410. In this case, the secondary battery can be more effectively protected from swelling phenomenon and external physical shock, which may occur locally or in part.

After configuring the secondary battery through the cooling plate 400 as described above, as shown in FIG. 5, the positive electrodes of the plurality of battery cells 110 and 120 are electrically connected in parallel to each other. Electrically connect the 310 and the negative electrode 320 to the relay 500, respectively.

Since the folded wing 230 of the secondary battery 100 configured as described above is configured with one common pouch 200 as described above, one surface of the secondary battery 100 further penetrates water and the like. Not only can be minimized, it is possible to more effectively prevent the leakage of electrolyte due to the sealing failure between the pouch surface.

In addition, by manufacturing a secondary battery by folding one side, the area subject to sealing can be essentially reduced, thereby shortening or simplifying the process and improving process yield.

10 and 11 illustrate a form in which four battery cells are connected in parallel according to another embodiment of the present invention. As illustrated in FIG. 10, four battery cells are provided in one common pouch 200, and a cooling plate 400 is interposed between the battery cells.

As described above, it is preferable to set the direction of each electrode so that the electrical connection between the same electrodes is easily connected through the relay 500, and the folding directions of the cells may be alternated based on A1, A2, A3, and the like. It is folded so that it is possible.

As in the exemplary embodiment illustrated in FIGS. 10 and 11, a considerable number of secondary battery cells can be easily configured according to an exemplary embodiment of the present invention.

Although the present invention has been described above by means of limited embodiments and drawings, the present invention is not limited thereto and will be described below by the person skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of the claims.

100: secondary battery 110, 120: battery cell
200: pouch 210: electrode current collector storage space
230: folded wing 300: electrode collector
310, 320: electrode 400: cooling plate
410: metal base plate 420: buffer member
500: relay

Claims (8)

A plurality of battery cells facing each other including an electrode assembly having a positive electrode and a negative electrode formed therein and a pouch for receiving the electrode assembly;
A relay electrically connecting the positive and negative electrodes of the plurality of battery cells so that the plurality of battery cells are connected in parallel; And
Parallel type secondary battery with a cooling structure, characterized in that it comprises a cooling plate interposed between the plurality of battery cells facing. The method of claim 1, wherein the plurality of battery cells,
Each electrode assembly is continuously provided in one common pouch, and the pouch portions between the electrode assemblies are folded to face each other. The method of claim 2, wherein the cooling plate,
Parallel type secondary battery with a cooling structure, characterized in that the metal plate. The method of claim 3, wherein the metal plate,
Parallel type secondary battery with a cooling structure, characterized in that made of aluminum. The method of claim 4, wherein the cooling plate,
Parallel type secondary battery comprising a cooling structure, characterized in that the size made corresponding to the size of the electrode assembly. The method of claim 5, wherein the cooling plate,
Parallel type secondary battery with a cooling structure, characterized in that consisting of a plurality of divided metal plate. The method of claim 2, wherein the cooling plate,
Parallel type secondary battery with a cooling structure, characterized in that the buffer member of the elastic material is provided on the outer peripheral surface. The method of claim 7, wherein the buffer member,
Parallel type secondary battery comprising a cooling structure, characterized in that a plurality of unit objects are provided to be spaced apart from each other on the surface of the cooling plate.

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