KR20140148121A - Pouch case and secondary battery including the same - Google Patents

Abstract

Disclosed is a pouch case to maintain the optimal performance of a secondary battery even at low temperature, and a secondary battery including the same. A secondary battery according to the present invention includes an electrode assembly where an anode plate faces a cathode plate; and a pouch case which receives the electrode assembly in an interior space and includes a metal layer, an external insulating layer, an internal bonding layer, and a heating layer which generates heat when a current flows.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a pouch case and a secondary battery including the same,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a technique for manufacturing a secondary battery, and more particularly, to a pouch outer casing and a pouch-type secondary battery including the same.

In recent years, demand for portable electronic products such as notebook computers, video cameras, and portable telephones has been rapidly increased, and development of batteries, robots, and satellites for energy storage has been accelerated. Thus, a high performance rechargeable battery Researches are being actively conducted.

The secondary rechargeable batteries are nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among them, lithium secondary batteries have almost no memory effect compared to nickel- It is very popular because of its low self-discharge rate and high energy density. Generally, such a secondary battery can be classified into a can-type secondary battery and a pouch-type secondary battery depending on the external appearance and application form.

Fig. 1 is a cross-sectional view showing the construction of a general pouch-type secondary battery, and Fig. 2 is an enlarged view of a portion A in Fig.

As shown in FIGS. 1 and 2, the pouch type secondary battery includes an electrode assembly 20 and a pouch outer casing 10. As shown in FIG.

Here, the pouch exterior member 10 may be composed of an upper pouch T and a lower pouch B, and accommodates the electrode assembly 20 in an internal space formed by the upper pouch T and the lower pouch B. The pouch sheathing material 10 is formed to have a predetermined layered structure having an order of the insulating layer 13, the metal layer 12, and the adhesive layer 11 from the outside to the inside in this order. Therefore, the pouch exterior member 10 can be sealed by bonding the adhesive layer 11 of the upper pouch T and the adhesive layer 11 of the lower pouch B to each other at the sealing portion.

On the other hand, recently, as carbon energy is gradually exhausted and interest in the environment is increasing, attention is focused on hybrid cars and electric vehicles worldwide, including the United States, Europe, Japan, and Korea. The most important components in such hybrid vehicles and electric vehicles are battery packs that give drive power to vehicle motors. Since hybrid vehicles and electric vehicles can obtain the driving force of the vehicle through charging and discharging of the battery pack, the fuel efficiency is higher than that of the vehicle using only the engine, and the users are increasingly increasing in terms of not discharging or reducing pollutants. to be. The battery of such a hybrid car or electric vehicle includes a plurality of pouch type secondary batteries, and the plurality of pouch type secondary batteries are connected in series and in parallel to each other to improve capacity and output.

However, in the case of a battery pack for a vehicle used in such a hybrid car or an electric vehicle, unlike a battery pack used in a general portable electronic product, it is frequently encountered in an extreme situation due to its nature to be mounted on an automobile. In particular, automobiles can be operated in areas with high winter or latitude, in which case the battery pack can be placed in a very low temperature for long periods of time.

However, when the battery pack is placed in a low temperature condition, the performance of the secondary battery included therein may be deteriorated. That is, the secondary battery can exhibit optimum performance in a predetermined temperature range. If the vehicle is parked or operated for a long time in the winter, the secondary battery can be placed in a state outside the proper temperature range. Therefore, at this time, the performance of the secondary battery deteriorates, so that the battery pack for the vehicle may not operate properly.

In addition, recently, interest and development of a power storage device called an ESS (Energy Storage System) has been increasing. Such a power storage device may include a much larger number of pouch type secondary batteries than a battery pack for a vehicle. However, such a power storage device can be placed outdoors, which can cause a situation in which the vehicle is placed in a low temperature condition as in an automobile. Therefore, even in the case of a secondary battery used in such a power storage device, the performance may deteriorate due to a low temperature.

Of course, in order to solve such a problem, it may be considered to increase the temperature of the secondary battery by supplying heat to the secondary battery through a separate heating device. However, in this case, the cost and volume of the heating device increase And there is also a problem that heat supplied from the heating device is difficult to be uniformly distributed to all the secondary batteries.

For example, in the case of a vehicle battery pack, a large number of pouch-shaped secondary batteries may be stacked in a battery pack. Even if heat is supplied from the outside of the battery pack, the secondary battery located outside the battery pack The heat is supplied well, but the secondary battery located inside the battery pack can not be supplied with the heat and the performance deterioration thereof can not be prevented. Also, when the heating device supplies a large amount of heat to the secondary battery located inside the battery pack, excessive heat may be supplied to the secondary battery located outside the battery pack, which may degrade the performance of the secondary battery. .

Moreover, such problems can be more serious in a power storage device including a much larger number of secondary batteries as well as in a vehicle battery pack.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a pouch exterior member and a secondary battery including the same, which can maintain optimal performance of the secondary battery even at a low temperature.

Other objects and advantages of the present invention can be understood by the following description, and will be more clearly understood by the embodiments of the present invention. It will also be readily apparent that the objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

According to an aspect of the present invention, there is provided a secondary battery including: an electrode assembly including a positive electrode and a negative electrode opposite to each other; And a pouch outer casing containing the electrode assembly in an inner space and including a metal layer, an outer insulating layer, an inner adhesive layer, and a heating layer that generates heat when current flows.

Preferably, the outer insulating layer includes a first insulating layer and a second insulating layer which are sequentially stacked in an outward direction from the inside of the secondary battery, and the heat generating layer includes a first insulating layer and a second insulating layer, .

Also, preferably, the pouch exterior member further includes a first electrode pattern and a second electrode pattern formed to be spaced apart from each other by a predetermined distance so that current supplied and supplied may flow through the heating layer.

More preferably, the first electrode pattern and the second electrode pattern are formed outside the heating layer.

Also, preferably, the first electrode pattern and the second electrode pattern are formed parallel to each other in a shape elongated in one direction.

More preferably, a plurality of the first electrode patterns and the second electrode patterns are formed, and are alternately arranged in parallel on the surface of the heating layer.

Also, preferably, the plurality of first electrode patterns and the plurality of second electrode patterns are formed so that at least one side thereof is connected to the same polarity.

Also, preferably, the outer insulating layer is formed with a hole such that at least a part of the first electrode pattern and at least a part of the second electrode pattern are respectively exposed to the outside.

Preferably, the pouch exterior member further includes a first lead wire and a second lead wire connected to the first electrode pattern and the second electrode pattern, respectively, and exposed to the outside of the outer insulating layer.

Preferably, the heating layer is in the form of an area heating element.

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

According to another aspect of the present invention, there is provided an automobile comprising the secondary battery according to the present invention.

According to another aspect of the present invention, there is provided a pouch outer sheath for accommodating an electrode assembly in an inner space, comprising: a metal layer made of a metal material; An outer insulating layer formed on the outer side of the metal layer; An inner adhesive layer formed on the inner side of the metal layer; And a heating layer that generates heat when current flows.

According to the present invention, heat can be generated in the pouch case itself included in the secondary battery.

Therefore, even if the secondary battery is placed in a low-temperature state, it is possible to prevent performance deterioration due to low temperature through self-heating of the pouch exterior member, and to operate at a temperature condition in which the secondary battery can exhibit optimal performance.

In particular, when the pouch-type secondary battery according to the present invention is applied to a battery pack for an automobile or a power storage device mainly used outdoors, even if the ambient temperature is lowered due to a climate change or the like, Can be prevented.

Further, even if a plurality of pouch type secondary batteries are included in a battery pack for an automobile or a power storage device, it is not necessary to provide a heating device or an air conditioning system for supplying heat to each of the pouch type secondary batteries, The manufacturing cost and volume of the device can be reduced.

In addition, since heat is generated in the pouch-type secondary battery itself, it is possible to maintain each secondary battery at an appropriate temperature irrespective of the number and arrangement of the pouch-type secondary batteries.

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 cross-sectional view showing a configuration of a general pouch-type secondary battery.
2 is an enlarged view of a portion A in Fig.
3 is an exploded perspective view schematically showing a configuration of a pouch type secondary battery according to an embodiment of the present invention.
4 is an enlarged cross-sectional view schematically showing a cross section of a portion B in Fig.
5 is a top view schematically showing the shape of an electrode pattern formed on a heating layer according to an embodiment of the present invention.
6 is a cross-sectional view schematically showing the electrode pattern forming structure of a pouch outer cover material according to another embodiment of the present invention.
7 is a view schematically showing a configuration of a part of a cross section of a pouch exterior material according to an embodiment of the present invention.
Fig. 8 is a view schematically showing a configuration of a part of a cross section of a pouch exterior material according to another embodiment of the present invention.
Figs. 9 and 10 are perspective views schematically showing different embodiments of a configuration in which a heating layer is included in the pouch exterior member in the form of an area heating element.
11 is a perspective view schematically showing a heat generating layer forming structure of a secondary battery according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be construed in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined.

Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

3 is an exploded perspective view schematically showing a configuration of a pouch type secondary battery according to an embodiment of the present invention. 4 is an enlarged cross-sectional view schematically showing a cross section of a portion B in Fig.

3 and 4, the pouch type secondary battery according to the present invention includes an electrode assembly 200 and a pouch case 100.

The electrode assembly 200 is configured such that the positive electrode plate and the negative electrode plate are opposed to each other, and a separator may be interposed between the positive electrode plate and the negative electrode plate. The electrode assembly 200 may be formed in a state in which a plurality of positive electrode plates and negative electrode plates are stacked with a separator interposed therebetween, or one positive electrode plate and a negative electrode plate may be wound with a separator interposed therebetween.

The electrode plates of the electrode assembly 200 are formed as a structure in which a current collector is coated with an active material slurry. The slurry may be formed by stirring a granular active material, an auxiliary conductor, a binder, a plasticizer, etc., . Each of the electrode plates may have an uncoated portion to which no slurry is applied, and an electrode tab corresponding to each electrode plate may be formed on the uncoated portion. One or more of these electrode tabs, that is, the positive electrode tab 210 and the negative electrode tab 220, may be formed on the positive electrode plate and the negative electrode plate, respectively. The positive electrode tab 210 or the negative electrode tab 220 may protrude from the positive electrode plate or the negative electrode plate and may be formed of the same material as the positive electrode collector or the negative electrode collector.

The pouch outer casing 100 has a concave inner space as indicated by R in the drawing, and the electrode assembly 200 and the electrolyte can be accommodated in the inner space. The pouch exterior member 100 may be composed of an upper pouch T and a lower pouch B to facilitate insertion of the electrode assembly 200. [ The upper and lower pouches T and B may have a concave space for accommodating the electrode assembly 200. The upper and lower pouches T and B may be formed in the upper and lower pouches T and B. However, (B) may be formed in a concave shape.

The upper pouch T and the lower pouch B are each provided with a sealing portion S at the edge of the inner storage space and the sealing portions S are adhered to each other so that the inner storage space can be sealed have.

4, in order to seal the electrode assembly 200 and the electrolytic solution contained in the pouch outer casing 100 and protect them from the outside, the pouch outer casing 100 includes a metal layer 120, an outer insulating layer 130, And an inner adhesive layer 110, as shown in FIG.

The metal layer 120 secures the mechanical strength of the pouch case 100, and prevents gas, moisture, and the like from the outside of the secondary battery from flowing into the inside of the secondary battery. Here, the metal layer 120 may be made of aluminum. In the case of aluminum, a mechanical strength of a predetermined level or higher can be secured, but the weight is light, and it is advantageous to improve the electrochemical properties of the electrode assembly 200 and the electrolytic solution, and to improve heat dissipation. However, the present invention is not limited to the metal layer 120, and various materials other than aluminum may be used as the metal layer 120 of the present invention.

The external insulating layer 130 is made of a material having electrical insulation and is formed on the outside of the metal layer 120. Here, the outer side refers to a portion located in the opposite direction to the direction in which the electrode assembly 200 is positioned, that is, the outer direction of the secondary battery, with respect to the metal layer 120. For example, referring to the upper pouch T as shown in FIG. 4, the outer side of the metal layer 120 refers to the upper side of the metal layer 120. Conversely, when the lower pouch B is used as a reference, the outer side of the metal layer 120 may be referred to as the lower side of the metal layer 120. [

The outer insulating layer 130 is provided on the outer side of the secondary battery 120 so as to protect the battery from the outside and electrically insulate the electrode assembly 200 and the metal layer 120 from the outside .

The outer insulating layer 130 may be formed of a material such as polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, an acrylic polymer, a polyacrylonitrile, a polyimide, a polyamide, a cellulose, an aramid, And at least one material selected from the group consisting of an ester, polyparaphenylene benzobisoxazole, polyarylate, teflon, and glass fiber.

In particular, the outer insulating layer 130 may be formed of a material including polyethylene terephthalate (PET) and / or oriented nylon.

The outer insulating layer 130 may have a single film structure made of any one material or a composite film structure in which two or more materials are respectively formed in layers.

The internal adhesive layer 110 is made of a material having adhesiveness and is formed inside the metal layer 120. Here, the inside has the opposite meaning to the outside as described above, and refers to a portion in which the electrode assembly 200 is located, that is, a portion located inside the secondary battery with respect to the metal layer 120. For example, when referring to the upper pouch T as shown in FIG. 4, the inside of the metal layer 120 means the lower side of the metal layer 120. On the other hand, the meaning of the outside and inside can be similarly applied.

The inner adhesive layer 110 may be formed of a material having electrical insulation so that the metal layer 120 and the electrode assembly 200 or the metal layer 120 and the electrolyte or metal layer 120 and the electrode assembly 200 can be electrically insulated. Lt; / RTI > In addition, the inner adhesive layer 110 can be adhered to each other by applying heat and / or pressure to each other to provide sealing at the sealing portion. That is, since the upper pouch T and the lower pouch B are bonded to each other at the sealing portion and the pouch exterior member 100 can be sealed, the inner pouch T and the lower pouch B can be sealed with the inner adhesive layer 110 located at the innermost side of the upper pouch T, The inner adhesive layer 110 located on the innermost side of the pouch B is bonded to each other.

As described above, the internal adhesive layer 110 may be made of a material having adhesiveness and electrical insulation. For this purpose, the inner adhesive layer 110 may be formed of a material such as polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, an acrylic polymer, a polyacrylonitrile, a polyimide, a polyamide, a cellulose, an aramid, a nylon, Polyvinylidene fluoride, polyvinylidene fluoride, polyparaphenylene benzobisoxazole, polyarylate, Teflon, and glass fiber.

In particular, the internal adhesive layer 110 may be made of a material containing non-oriented polypropylene (CPP).

Also, the internal adhesive layer 110 may have a single film structure made of any one material, or a composite film structure in which two or more materials are respectively formed in layers. For example, the inner adhesive layer 110 includes an innermost layer made of a non-oriented polypropylene material and an adhesive layer made of an acid-modified polypropylene material such as PPA (polypropylene-co-acrylic acid) The adhesion between the innermost layer and the metal layer 120 can be complemented through the adhesive layer while allowing the adhesive layer T and the lower pouch B to be fused.

Particularly, the pouch outer cover 100 according to the present invention further includes a heat generating layer 140 in addition to the metal layer 120, the outer insulating layer 130, and the inner adhesive layer 110.

The heat generating layer 140 can generate heat when a current flows through the heat generating layer 140 itself. For example, the heating layer 140 may be configured to form at least one layer inside the pouch case 100 in the form of a conductive compound containing a conductive carbon black in a thermoplastic resin material. In this case, when a current is supplied to the heating layer 140, a current can flow through the heating layer 140, and heat can be generated in the heating layer 140 due to the electrical resistance of the heating layer 140.

However, the heating layer 140 of the present invention is not limited to the carbon black, and various materials capable of generating heat by current flow may be used as the heating layer 140 of the present invention. Can be used. For example, the heating layer 140 may be formed using a thin metal plate or carbon fiber.

The heat generating layer 140 may be stacked on a predetermined position of the pouch case 100. In particular, the heat generating layer 140 may be interposed between at least one of the outermost layer and the innermost layer.

Preferably, the heating layer 140 may be included in the pouch outer casing 100 in a form interposed within the outer insulating layer 130, as shown in FIG. That is, the outer insulating layer 130 may be formed in the form of a composite film including a first insulating layer 131 and a second insulating layer 132 which are sequentially stacked from the inner side to the outer side of the secondary battery, (140) may be interposed between the first insulating layer (131) and the second insulating layer (132).

In this case, the first insulating layer 131 located inside the secondary battery is made of a material containing stretched nylon, and the second insulating layer 132 located outside the secondary battery relatively includes polyethylene terephthalate As shown in FIG.

An adhesive layer composed of an adhesive material may be interposed between the first insulating layer 131 and the heat generating layer 140 to enhance adhesion between the first insulating layer 131 and the heat generating layer 140 have.

Also, an adhesive layer may be interposed between the first insulating layer 131 and the metal layer 120 to enhance adhesion.

4, the heat generating layer 140 is interposed in the external insulating layer 130. However, the heat generating layer 140 may be formed in the internal adhesive layer 110, Or between the metal layer 120 and the external adhesive layer 110, or between the external adhesive layer 120 and the external adhesive layer 130, or between the metal layer 120 and the internal adhesive layer 110.

In addition, the heat generating layer 140 may be formed of a plurality of layers other than one layer.

Preferably, the pouch outer cover 100 according to the present invention may further include a first electrode pattern 151 and a second electrode pattern 152, as shown in FIG.

The first electrode pattern 151 and the second electrode pattern 152 are formed in the heat generating layer 140 so that a current can flow through the heat generating layer 140 by supplying the current to the heat generating layer 140, As the pattern, it may be made of a conductive material such as a metal. The first electrode pattern 151 and the second electrode pattern 152 may be connected to the positive terminal and the negative terminal of the current supplying device and may be connected to each other through a heating layer 140, Is formed to be spaced apart.

For example, when the first electrode pattern 151 is connected to the positive terminal of the current supply device and the second electrode pattern 152 is connected to the negative terminal of the current supply device, Electrode pattern 151 to the heating layer 140 through the one-electrode pattern 151 as shown in FIG. The current supplied to the heat generating layer 140 may flow through the heat generating layer 140. In this process, heat is generated in the heat generating layer 140 due to the resistance of the heat generating layer 140, The electrode assembly 200 of FIG. Then, the current flowing through the heating layer 140 flows out of the heating layer 140 through the second electrode pattern 152.

Preferably, the first electrode and the second electrode pattern 152 may be elongated in one direction. The formation of the first electrode pattern 151 and the second electrode pattern 152 will be described in detail with reference to FIG.

5 is a top view schematically showing the shape of an electrode pattern formed on the heating layer 140 according to an embodiment of the present invention.

Referring to FIG. 5, the first electrode pattern 151 and the second electrode pattern 152 may each be formed in a shape elongated in one direction, that is, in the form of a bar. The first electrode pattern 151 and the second electrode pattern 152 may be disposed parallel to each other on the heat generating layer 140 and spaced apart from each other by a predetermined distance. According to the configuration in which the bar-shaped first electrode pattern 151 and the second electrode pattern 152 are formed parallel to each other, the distance between the first electrode pattern 151 and the second electrode pattern 152 is constant So that the heat can be uniformly generated throughout the heat generating layer 140.

5, the first electrode pattern 151 and the second electrode pattern 152 may include a plurality of electrode patterns, respectively. In this case, the plurality of first electrode patterns 151 and the plurality of second electrode patterns 152 may be alternately arranged on the surface of the heating layer 140 in parallel. For example, the first electrode pattern 151 and the second electrode pattern 151 may be formed in a manner such that the second electrode pattern 152 is positioned immediately after the first electrode pattern 151, The two-electrode patterns 152 may be arranged in such a manner that they are alternately formed one after the other sequentially.

Preferably, in the embodiment where a plurality of the first electrode patterns 151 and the plurality of the second electrode patterns 152 are formed, the patterns may be configured such that patterns of the same polarity are connected to each other at least on one side . For example, the plurality of first electrode patterns 151 may be configured such that the left ends thereof are connected to each other as indicated by c1 in FIG. Also, the plurality of second electrode patterns 152 may be configured such that the right ends thereof are connected to each other as indicated by c2 in Fig.

In this case, both terminals of the current supply device are connected to the first electrode pattern 151 and a part of the second electrode pattern 152, respectively, so that the first electrode pattern 151 and the second electrode pattern 152 So that current can flow. For example, even if the anode of the current supply device is connected to only a part of the plurality of first electrode patterns 151, since the first electrode patterns 151 are connected to each other, Can be supplied. According to this embodiment, even if a terminal is connected only to a part of the first electrode pattern 151 and the second electrode pattern 152, a current can be supplied through the entire electrode pattern.

In particular, the first electrode pattern 151 and the second electrode pattern 152 may be formed such that a connecting portion is extended as shown in FIG. 5. In this case, both terminals of the current supplying device are extended Respectively.

The first electrode pattern 151 and the second electrode pattern 152 may be formed on the outer side of the heat generating layer 140. 4, the first electrode pattern 151 and the second electrode pattern 152 are located on the upper portion of the heat generating layer 140, And may be included in the upper pouch (T) in a form. According to this embodiment, since the electrode patterns are not disposed between the heating layer 140 and the electrode assembly 200 and the electrolyte, heat supply to the electrode assembly 200 and the electrolyte by the heating layer 140 can be prevented, Lt; / RTI > In addition, the connection of the terminals of the current supply device and the electrode patterns can be made easier.

The first electrode pattern 151 and the second electrode pattern 152 may be formed at various positions with respect to the heat generating layer 140. The present invention is not limited to these embodiments.

6 is a cross-sectional view schematically showing the electrode pattern forming structure of the pouch outer casing 100 according to another embodiment of the present invention.

Referring to FIG. 6, the first electrode pattern 151 is formed on the outer side of the heat generating layer 140, and the second electrode pattern 152 is formed on the heat generating layer 140 As shown in Fig. According to this embodiment, since current flows as a whole along the thickness direction of the heat generating layer 140, the heat generating efficiency by the heat generating layer 140 can be improved.

4 and 6, a portion of the electrode pattern having the same polarity may be formed on the outer side of the heat generating layer 140 and the remaining portion may be formed on the inner side of the heat generating layer 140.

The first electrode pattern 151 and the second electrode pattern 152 may be formed on the inner side of the heating layer 140 or at least a part of the first electrode pattern 151 may be formed in the middle of the heating layer 140 in the thickness direction of the heating layer 140. [ Or the like.

Preferably, holes may be formed in the pouch exterior member 100 such that the first electrode patterns 151 and the second electrode patterns 152 are exposed to the outside.

7 is a view schematically showing a configuration of a part of a cross section of a pouch outer casing 100 according to an embodiment of the present invention.

Referring to FIG. 7, a first hole H1 and a second hole H2 may be formed in the outer insulating layer 130 of the pouch case 100. Particularly when the external insulating layer 130 includes the first insulating layer 131 and the second insulating layer 132 and the heat generating layer 140 is formed between the first insulating layer 131 and the second insulating layer 132 The first hole H1 and the second hole H2 may be formed in the second insulating layer 132 located outside the heat generating layer 140. [ The first hole H1 is a hole formed in a part of the second insulating layer 132 so that the first electrode pattern 151 is exposed to the outside of the secondary battery and the second hole H2 is a hole formed in the second electrode layer 152, Is formed in a part of the second insulating layer 132 so as to be exposed to the outside of the secondary battery.

According to the embodiment in which the hole is formed in the outer insulating layer 130 of the pouch case 100, the electrode terminal of the current supplying device can be easily connected to the electrode pattern through the hole. For example, the positive terminal of the current supply device is connected to the first electrode pattern 151 through the first hole H1, and the negative terminal of the current supply device is connected to the second electrode pattern 152, respectively. Accordingly, the current supplied from the current supply device may flow to the heating layer 140 through the electrode pattern, thereby generating heat in the heating layer 140.

5, the plurality of first electrode patterns 151 and the plurality of second electrode patterns 152 are connected to each other at one ends thereof, and the extended portions of the connected portions are denoted by d1 and d2, respectively. The hole may be formed on the outside of such an extension portion. For example, if the configuration of FIG. 5 represents the upper pouch T, the first hole H1 is formed in the outer insulating layer 130 located above the portion indicated by d1, and the second hole H2 is formed in the outer insulating layer 130, may be formed in the outer insulating layer 130 located on the upper portion of the portion denoted by d2.

However, in the present invention, the electrode patterns of the heat generating layer 140 may be connected to the electrode terminals of the current supplying device in various manners other than a method of forming the holes in the pouch case 100. For example, the electrode patterns of the heating layer 140 may be connected to the current supply device through the lead wires, which will be described with reference to FIG.

Fig. 8 is a view schematically showing a configuration of a part of a cross section of a pouch exterior material 100 according to another embodiment of the present invention.

Referring to FIG. 8, the pouch case 100 of the secondary battery according to the present invention may further include lead wires. Here, the lead wire may be composed of the first lead wire W1 and the second lead wire W2. At this time, one end of the first lead wire W1 may be connected to the first electrode pattern 151 and the other end may be exposed to the outside of the external insulating layer 130. [ One end of the second lead wire W2 may be connected to the second electrode pattern 152 and the other end may be exposed to the outside of the external insulating layer 130. [

According to the embodiment where the lead wire connected to the electrode pattern is exposed to the outside of the external insulating layer 130, the electrode terminal of the current supplying device can be easily connected to the electrode pattern through the lead wire. For example, the positive terminal of the current supply device is connected to the first electrode pattern 151 by being connected to the other end of the first lead wire W1, and the negative terminal of the current supply device is connected to the other end of the second lead wire W2 The second electrode pattern 152 can be connected to the second electrode pattern 152.

8, the lead wire penetrates the external insulating layer 130 in the vertical direction (thickness direction) and is exposed to the outside. However, such a lead wire does not penetrate the external insulating layer 130, but extends in the horizontal direction So as to be exposed to the sealing portion of the pouch exterior member 100.

In the above embodiments, the current supplying device is connected to the electrode pattern through the hole formed in a specific portion of the pouch or the lead wire provided at a specific portion, but the present invention is not necessarily limited to such an embodiment . That is, the current supply device can be connected to the electrode pattern in various ways without depending on holes or lead wires.

For example, the connecting portion of the electrode pattern may be extended to the sealing portion of the pouch case 100 so as to be exposed to the side of the sealing portion of the pouch case 100. In this case, the current supply device can be connected to the electrode pattern exposed on the side surface of the pouch outer casing 100, so that current can flow through the heating layer 140 through the electrode pattern.

In the above embodiment, a current is supplied to the heat generating layer 140 by a separate current supplying device and a current flows through the heat generating layer 140. However, It is also possible to adopt a configuration in which current is supplied from itself. For example, the positive electrode tab may be connected to the first electrode pattern 151, and the negative electrode tab may be connected to the second electrode pattern 152 so that the secondary battery itself can supply electric power to be used for heat generation. In this case, a switch may be provided between the electrode tab and the electrode pattern. Such a switch is controlled through a control unit such as an MCU of the battery pack, so that when the heat is supplied to the secondary battery, Can be supplied.

Although the first electrode pattern 151 and the second electrode pattern 152 are formed on the heat generating layer 140 in the above embodiment, the present invention is not limited thereto. For example, only one of the first electrode pattern 151 and the second electrode pattern 152 may be formed on the heat generating layer 140 according to an embodiment of the present invention.

In addition, in the present invention, an electrode pattern may not be formed on the heat generating layer 140 in addition to the embodiment where the electrode pattern is formed on the heat generating layer 140 as described above. In this case, the current supplying device may connect the positive terminal and the negative terminal to one end and the other end of the heat generating layer 140, respectively, so that current flows through the heat generating layer 140.

Preferably, in the case of the pouch case 100 of the secondary battery according to the present invention, the heat generating layer 140 may be in the form of a planar heating element.

As described above, according to the embodiment in which the heat generating layer 140 is formed in the form of a planar heating element, the heat can be uniformly supplied to the electrode assembly 200 as a whole, so that the effect of preventing the performance deterioration at low temperatures can be further improved.

9 and 10 are perspective views schematically showing different embodiments of the constitution in which the heat generating layer 140 is included in the pouch exterior member 100 in the form of an area heating element. 9 and 10, other materials such as a PET layer may be laminated on the outside of the heat generating layer 140. However, for convenience of explanation, the heat generating layer 140 is displayed on the outside in a shade form.

9, the heat generating layer 140 may be formed on the entire surface of the pouch outer casing 100 from the left end to the right end on a horizontal plane. That is, the heat generating layer 140 may be formed not only in the receiving portion R but also in the sealing portion S in the pouch case 100. According to this embodiment, when the pouch exterior member 100 is manufactured in the form of a film elongated in one direction, the pouch exterior member 100 used for one secondary battery does not need to be divided for each unit, It is possible to manufacture one pouch skin member 100 in such a manner that a heating body is longly applied along the longitudinal direction, the pouch film is cut to an appropriate length, and then the receiving portion R is formed. Therefore, according to the heat-generating layer 140, it is possible to manufacture the pouch case 100 more easily and easily.

9, the heat generating layer 140 is not formed in a part of the sealing part at the front end and the rear end of the pouch case 100. However, the heat generating layer 140 may be formed in such a part Of course it is. In this case, the heat-generating layer 140 may be provided on the entire surface of the pouch outer casing 100.

10, the heat generating layer 140 may not be formed in the sealing portion S of the pouch outer casing 100 but may be formed only in the receiving portion R of the pouch outer casing 100. That is, the heat generating layer 140 may be provided only on the upper side of the accommodating space in which the electrode assembly 200 and the electrolyte are housed. According to this embodiment, the application amount of the heating layer 140 can be reduced, thereby reducing the cost.

9 and 10 are merely examples, and the heat generating layer 140 may be formed in various other types of surface heating elements.

9 and 10, both the upper pouch T and the lower pouch B include a heating layer 140 in the form of an area heating element. According to this embodiment, since heat can be supplied from both the upper portion and the lower portion around the electrode assembly 200, the heat supply at a low temperature can be performed quickly and sufficiently.

However, the present invention is not necessarily limited to this embodiment, and a heating layer 140 may be formed only in one of the upper pouch T and the lower pouch B. According to this embodiment, the material cost and the like due to the formation of the heating layer 140 and the electrode pattern and the like can be reduced. Particularly, in many cases, a plurality of secondary batteries are used in a laminated form, such as a battery pack for an automobile or a power storage device. In a case where a heating layer 140 is formed only in one of the upper pouch T and the lower pouch B The side where the heat generating layer 140 is not formed may receive heat from the heat generating layer 140 of the adjacent secondary battery. For example, in the case of a secondary battery in which a heating layer 140 is formed only in the upper pouch T and a heating layer 140 is not formed in the lower pouch B, The heat generated from the heat generating layer 140 included in the upper pouch T of the secondary battery T and the heat generated from the heat generating layer 140 included in the upper pouch T of the secondary battery, Can be supplied.

In addition, the heating layer 140 may be included in both the upper pouch T and the lower pouch B, but may be differently positioned in the heating layer 140 of the upper pouch T and the lower pouch B .

11 is a perspective view schematically showing a structure for forming a heat generating layer 140 of a secondary battery according to another embodiment of the present invention. 11, the portion including the heat generating layer 140 is displayed in a shade on the outside of the upper pouch T and the lower pouch B for convenience of explanation.

11, when the upper pouch T and the lower pouch B are divided into the front end portion and the rear end portion with respect to the front and rear center lines, the heating pads 140 are formed only at the rear end of the upper pouch T And the heat generating layer 140 may be formed only at the front end of the lower pouch B. In this case, heat can be supplied to the rear end of the electrode assembly 200 by the heating layer 140 of the upper pouch T, and a heat generating layer (not shown) of the lower pouch B is formed at the front end of the electrode assembly 200 140, respectively.

According to this embodiment, both the upper pouch T and the lower pouch B are partially formed with the heating layer 140 to reduce the application amount of the heating layer 140, while the upper pouch T and the lower pouch B B may be formed at different positions so that the heat supplying portions are complementary to each other, so that heat can be supplied to the electrode assembly 200 as a whole.

In the meantime, it is needless to say that the heat generating layer 140 may be included in the pouch outer casing 100 in various forms other than the surface heat generating body.

The battery pack according to the present invention may include the above-described secondary battery.

Here, the battery pack may include a controller for controlling whether or not a current is supplied to the heat generating layer 140. For example, the control unit controls the switch provided between the current supply device and the first electrode pattern 151 so that current is supplied to the heating layer 140 to generate heat.

The battery pack may include a temperature measuring unit for measuring a temperature of the secondary battery. In this case, the temperature measuring unit may measure the temperature of the secondary battery and transmit the measured temperature information to the control unit. Then, the controller may determine whether the temperature measured by the temperature measuring unit is lower than a predetermined temperature, and if it is determined that the temperature is lower than the predetermined temperature, a current may be supplied to the heating layer 140.

The secondary battery according to the present invention can be applied to an automobile such as an electric car or a hybrid car. That is, the automobile according to the present invention may include the secondary battery according to the present invention in a battery pack. When the pouch-type secondary battery according to the present invention is used in a battery pack, the performance of the battery pack is deteriorated even at a low temperature due to heat generation of the heat-generating layer 140 Can be prevented.

In addition, the pouch type secondary battery according to the present invention can be applied to various other devices. For example, the secondary battery according to the present invention can be applied to a power storage device. That is, the power storage device according to the present invention may include a secondary battery according to the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be understood that various modifications and changes may be made without departing from the scope of the appended claims.

On the other hand, in the present specification. The terms "direction", such as "up", "down", "left", "right", "before" and "after" are used for convenience of explanation. However, the term can be expressed differently depending on the viewers' And will be apparent to those skilled in the art.

T: Upper pouch
B: Lower pouch
100: Pouch Exterior Material
110: internal adhesive layer
120: metal layer
130: outer insulating layer
131: first insulating layer
132: outer insulating layer
140: heating layer
151: first electrode pattern
152: second electrode pattern

Claims (15)

An electrode assembly disposed so that the positive electrode plate and the negative electrode plate face each other; And
Wherein the electrode assembly is housed in an inner space and includes a metal layer, an outer insulating layer, an inner adhesive layer, and a heating layer that generates heat when an electric current flows,
And a secondary battery. The method according to claim 1,
Wherein the outer insulating layer includes a first insulating layer and a second insulating layer that are sequentially stacked in an outward direction from the inside of the secondary battery, and the heat generating layer is disposed between the first insulating layer and the second insulating layer And a secondary battery. 3. The method of claim 2,
Wherein the first insulating layer comprises stretched nylon, and the second insulating layer comprises polyethylene terephthalate. 3. The method of claim 2,
Wherein an adhesive layer is interposed between the first insulating layer and the heat generating layer. The method according to claim 1,
Wherein the pouch sheathing material further comprises a first electrode pattern and a second electrode pattern formed so as to be spaced apart from each other by a predetermined distance so that the supplied current flows through the heating layer. 6. The method of claim 5,
Wherein the first electrode pattern and the second electrode pattern are formed outside the heat generating layer. 6. The method of claim 5,
Wherein the first electrode pattern and the second electrode pattern are formed parallel to each other in a shape elongated in one direction. 8. The method of claim 7,
Wherein a plurality of the first electrode patterns and the second electrode patterns are formed, and are alternately arranged in parallel on the surface of the heating layer. 9. The method of claim 8,
Wherein the plurality of first electrode patterns and the plurality of second electrode patterns are formed so as to be connected to each other at least at the same polarity. 6. The method of claim 5,
Wherein a hole is formed in the outer insulating layer such that at least a part of the first electrode pattern and at least a part of the second electrode pattern are respectively exposed to the outside. 6. The method of claim 5,
Wherein the pouch outer casing further comprises a first lead wire and a second lead wire connected to the first electrode pattern and the second electrode pattern and exposed to the outside of the outer insulating layer. The method according to claim 1,
Wherein the heat generating layer is in the form of a planar heating element. A battery pack comprising the secondary battery according to any one of claims 1 to 12. 13. A vehicle comprising the secondary battery according to any one of claims 1 to 12. A pouch outer sheath for a secondary battery which accommodates an electrode assembly in an inner space,
A metal layer made of a metal material;
An outer insulating layer formed on the outer side of the metal layer;
An inner adhesive layer formed on the inner side of the metal layer; And
A heating layer for generating heat when current flows
Wherein the pouch exterior member comprises:

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