KR100624958B1 - Battery outer case having porous layer and lithium polymer battery using it - Google Patents

Abstract

The present invention relates to a battery exterior material having a porous outer layer and a lithium polymer battery using the same. The technical problem to be solved is to improve heat dissipation performance and reactivity of a positive temperature device, and to improve mechanical strength, impact resistance, corrosion resistance, moldability, and other properties. It is to improve the adhesive strength with the member.

To this end, the gist of the solution according to the present invention is a metal plate having an approximately flat first surface and an approximately flat second surface opposite thereto, a porous outer layer formed to a certain thickness on the first surface of the metal plate, Disclosed is a battery packaging material made of modified polypropylene having a predetermined thickness on two surfaces.

In addition, the gist of the solution according to the present invention is that the lithium polymer battery having improved positive reactivity of the positive temperature element by allowing the positive temperature element electrically connected to the protective circuit board itself or the outside thereof to be in direct contact with the porous outer layer of the battery case. Is initiated.

Battery exterior material, porous outer layer, metal plate, positive temperature element, protective circuit board

Description

Battery outer material having a porous outer layer and a lithium polymer battery using the same {Battery outer case having porous layer and lithium polymer battery using it}

1A is a perspective view illustrating a battery exterior member having a porous outer layer according to an embodiment of the present invention, and FIG. 1B is an enlarged cross-sectional view taken along line 1-1 of FIG. 1A.

2 is a perspective view illustrating a state in which a battery exterior material is processed in a predetermined form to accommodate and seal an electrode assembly, an electrolyte, and the like in a battery exterior material in which a porous outer layer is formed according to an exemplary embodiment of the present invention.

3A is a perspective view illustrating a state in which a positive temperature device and a protection circuit board are electrically connected to an electrode tab in a lithium polymer battery according to an exemplary embodiment of the present invention, and FIG. 3B is electrically connected to the positive temperature device and a protection circuit board. It is a perspective view which shows the state after bending.

4 is a cross-sectional view taken along the line 2-2 of FIG. 3B.

5A to 5E are sequential diagrams illustrating a method of manufacturing a lithium polymer battery according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

100; Lithium polymer battery 110 according to the present invention; Battery exterior material by this invention

111; Metal plate 111a; Front page

111b; Second side 112; Porous outer layer

113; Modified polypropylene 114; First area

115; Second region 116; Drawing

117; Side folds 118; Front flat

120; Electrode assembly 121; Positive plate

122; Separator 123; Negative plate

124; Positive electrode tab 125; Negative electrode tab

130; Protective circuit board 131; Positive temperature element

The present invention relates to a battery exterior material having a porous outer layer and a lithium polymer battery using the same. More specifically, the porous outer layer may improve heat dissipation performance of a lithium polymer battery and also improve reactivity of a positive temperature device. It relates to a battery exterior material formed and a lithium polymer battery using the same.

In general, a lithium polymer battery refers to a battery in which a separator between a positive electrode plate and a negative electrode plate (hereinafter, a positive electrode plate, a negative electrode plate, and a separator is referred to as an electrode assembly) serves as a medium for ion conduction, that is, an electrolyte, in addition to a separation role in a lithium ion battery. .

The separator is formed of a gel polymer electrolyte, and prepared in a state in which the electrolyte is impregnated into the polymer in order to improve ionic conductivity. Advantages of the gel polymer electrolyte quality may include an excellent electrode conductivity, mechanical properties, and ease of manufacture, in addition to improved ion conductivity. As a representative gel polymer electrolyte, Bellcore's PVDF electrolyte is manufactured by mixing a copolymer of VDF (vinylidene fluoride), HFP (hexafluoroethylne), a plasticizer, and an inorganic additive to impregnate the gel by impregnating the electrolyte solution after film formation. .

On the other hand, the characteristics of a lithium polymer battery and a lithium ion battery are briefly compared as follows.

First, since the lithium polymer battery has a plate-like structure, it is not necessary to adopt the winding process required in the process of the lithium ion battery. Therefore, the electrode assembly can be laminated in the form of a plurality of plates, and the electrode assembly can be manufactured in a shape that is very suitable for the square structure.

Second, since the lithium polymer battery is injected into a cell in which all of the electrolyte solutions are integrated, there is almost no electrolyte solution exposed to the outside.

Third, since the lithium polymer battery can itself be a plate-like structure, it is not necessary to apply pressure when forming a square. Thus, it is crucially possible to manufacture the battery packaging material in a thin, flexible pouch instead of a thick, rigid square or cylindrical can.

As described above, since the lithium polymer battery uses a flexible pouch as the battery packaging material, the thickness of the lithium polymer battery can be significantly reduced compared to the can, and thus more electrode assemblies can be accommodated in the same volume. That is, the capacity of the battery can be significantly increased. In addition, since the battery packaging material is soft, the battery can be easily manufactured in a desired form, and therefore, there is an advantage that it is easy to attach to various electronic devices.

However, the pouch-type battery packaging material of the conventional lithium polymer battery has a problem of shortening the usable time of the battery due to the poor heat dissipation characteristics despite the increase in battery capacity and processability in various forms. That is, the pouch-type battery exterior material is formed on the surface of nylon or polyethylene terephthalate (PET) that degrades the heat dissipation performance basically, it can not actively respond to the heat generated during the charging and discharging of the battery, and also increase the temperature Accordingly, there is a problem that the amount of discharge increases and the usable time of the battery is drastically reduced.

In addition, in the pouch type battery packaging material, when the temperature of the battery becomes higher than the reference temperature according to the heat generation phenomenon of the battery, the electrode assembly or the electrolyte is decomposed, and as a result, a large amount of gas is generated. By increasing the breakdown voltage, there is a problem in that a so-called swelling phenomenon in which the battery itself swells is generated and the reliability of the battery is greatly reduced.

On the other hand, the lithium polymer battery is equipped with a positive temperature element in which the resistance increases in proportion to the temperature to block the charging current when the temperature increases. That is, by providing a positive temperature element at the protective circuit board itself or at the connection portion of the protective circuit board and the electrode assembly, the current flowing through the positive temperature element decreases or is blocked when the temperature of the battery increases. Of course, when the current flowing through the positive temperature element is reduced or blocked as described above, the heat generation phenomenon and the temperature increase phenomenon of the battery are generally stopped. Furthermore, the positive temperature element is adapted to contact a portion of the battery envelope so as to be sensitive to the temperature of the battery.

However, as already mentioned, the pouch-type battery case is formed of nylon or polyethylene terephthalate (PET) having poor heat dissipation on the surface thereof, so that heat generated therein cannot be quickly transferred to the positive temperature device. There are disadvantages. Therefore, even if the temperature of the battery itself increases, the positive temperature element does not react quickly, thereby causing a problem of greatly lowering the reliability of the battery.

In addition, the battery case of the conventional pouch type has a problem that the mechanical strength is weak and very vulnerable to external shock. For example, when the battery case is stuck to a sharp object (for example, a needle or a nail), a hole is easily formed, and when a battery bite is bitten, it is easily torn. In addition, when the sharp object as described above penetrates through the exterior material and contacts the electrode assembly therein, the positive electrode plate and the negative electrode plate are directly shorted, thereby causing the battery to ignite or explode.

An object of the present invention is to overcome the conventional problems as described above, to improve the heat dissipation performance in order to suppress the temperature increase occurring during charging and discharging, a battery outer material having a porous outer layer and a lithium polymer using the same It is to provide a battery.

Another object of the present invention is to form a porous outer layer on the surface of the battery packaging material, and by contacting the positive temperature device to the porous outer layer, thereby increasing the reactivity of the positive temperature device, the battery outer material having a porous outer layer and the same It is to provide a used lithium polymer battery.

It is another object of the present invention to provide a battery envelope having a porous outer layer and a lithium polymer battery using the same, which can improve mechanical strength, corrosion resistance, impact resistance, moldability, adhesion to other members, etc. of the battery envelope. .

As a means for achieving the above object, the constitution of the present invention comprises a metal plate having a substantially flat first face and a substantially flat second face opposite thereto, a porous outer layer formed to a certain thickness on the first face of the metal plate; The battery packaging material may include a modified polypropylene (CPP) formed on a second surface of the metal plate at a predetermined thickness.

The metal plate is an alloy of iron (Fe), carbon (C), chromium (Cr) and manganese (Mn), an alloy of iron (Fe), carbon (C), chromium (Cr) and nickel (Ni), or aluminum ( Al) may be any one selected.

The porous outer layer may be electrically insulating.

The porous outer layer may be any one selected from a thermally conductive polymer, a thermally conductive elastomer or a thermally conductive silicone elastomer.

The porous outer layer may be formed by mixing a ceramic powder and an adhesive resin.

The ceramic powder may be any one selected from aluminum oxide (Al ₂ O ₃ ), aluminum nitride (AlN), boron nitride (BN), beryllium oxide (BeO), or silicon carbide (SiC).

The porous outer layer may be a content of 5 to 50% by volume of the ceramic powder.

The porous outer layer may have a thickness of 5 ~ 10㎛.

The battery packaging material may include a first region having a drawing portion having a predetermined depth so that the electrode assembly can be accommodated, and a second region which starts to fold at one end of the first region and covers the drawing portion.

The battery packaging material may be one in which modified polypropylenes corresponding to the outer circumference of the drawing part of the first region and the second region are thermally bonded to each other.

In addition, as a means for achieving the above object, in the configuration of the present invention, a plurality of positive electrode plates and negative electrode plates are provided via a separator, and are extended by a predetermined length to the outside from the positive electrode plates and the negative electrode plates. An electrode assembly including a positive electrode tab and a negative electrode tab, and a first region having a drawing portion having a predetermined depth to accommodate the electrode assembly, and a second region provided to cover the drawing portion of the first region. It consists of a lithium polymer battery comprising an exterior material having an outer layer.

The packaging material includes a metal plate having a first substantially flat surface and a substantially flat second surface opposite thereto, a porous outer layer formed to a certain thickness on the first surface of the metal plate, and a predetermined thickness on the second surface of the metal plate. It may be made of modified polypropylene (CPP) formed.

The porous outer layer of the packaging material may be any one selected from a thermally conductive polymer, a thermally conductive elastomer or a thermally conductive silicone elastomer.

The porous outer layer may be formed by mixing a ceramic powder and an adhesive resin.

The ceramic powder may be any one selected from aluminum oxide (Al ₂ O ₃ ), aluminum nitride (AlN), boron nitride (BN), beryllium oxide (BeO), or silicon carbide (SiC).

The positive electrode tab and the negative electrode tab are electrically connected to the protective circuit board, and a positive temperature element may be further interposed between the negative electrode tab and the protective circuit board to be seated on the surface of the battery packaging material.

As described above, the present invention forms a porous outer layer that is electrically insulating and thermally conductive on the surface of the battery exterior material, thereby maximizing heat dissipation performance during charging and discharging of the battery, thereby improving battery life and reliability. .

In addition, the present invention is that the positive temperature element electrically connected between the electrode assembly and the protective circuit board is in direct contact with the above-described porous outer layer, thereby immediately detecting this when the battery heats to block or reduce the current flow, Reliability is greatly improved.

In addition, the present invention is also excellent in mechanical strength, corrosion resistance, impact resistance and the like by forming a porous outer layer on the surface of the battery packaging material.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, in order to describe in detail such that those skilled in the art can easily implement the present invention, the most preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. do. Other objects, features, and operational advantages, including the object, operation, and effect of the present invention will become more apparent from the description of the preferred embodiment.

For reference, the embodiments disclosed herein are only presented by selecting the most preferred embodiment in order to help those skilled in the art from the various possible examples, the technical spirit of the present invention is not necessarily limited or limited only by this embodiment In addition, various changes, additions and changes are possible within the scope without departing from the technical spirit of the present invention, as well as other equivalent embodiments will be found out.

1A is a perspective view illustrating a battery exterior member having a porous outer layer according to an embodiment of the present invention, and FIG. 1B is an enlarged cross-sectional view taken along line 1-1 of FIG. 1A.

As illustrated in FIGS. 1A and 1B, the battery packaging material 110 according to an exemplary embodiment of the present invention includes a metal plate 111, a porous outer layer 112, and a modified polypropylene 113.

First, the metal plate 111 has a first surface 111a that is approximately flat or completely flat, and a second surface 111b that is approximately flat or completely flat as an opposite surface thereof. The metal plate 111 is formed to have a thickness of approximately 20 to 100 μm between the first surface 111a and the second surface 111b. When the thickness of the metal plate 111 is 20 μm or less, the metal plate 111 may be easily broken or damaged during a drawing or folding process, and when the thickness of the metal plate 111 is 100 μm or more, drawing or folding is difficult, which is not preferable.

On the other hand, the metal plate 111 is an alloy of iron (Fe), carbon (C), chromium (Cr) and manganese (Mn), iron (Fe), carbon (C), chromium (Cr) and nickel (Ni) Alloy, aluminum (Al) or any one selected from the equivalents may be used, but the material is not limited thereto. However, when the metal plate 111 is made of a material containing iron, the mechanical strength is increased, and when the material containing aluminum is made, the heat dissipation performance is improved, so it is preferable to select a material appropriate for the purpose or purpose of use. In addition, when the metal plate 111 is made of a material containing iron, an alloy consisting of 84 to 88.2% of iron, 0.5% or less of carbon, 11-15% of chromium and 0.3-0.5% of manganese, iron 63.7 to 75.9%, and carbon Alloys of 0.1-0.3%, chromium 12-18% and nickel 7-12% are preferred. In addition, the metal plate 111 is any one selected from STS301, STS304, STS305, STS316L, or STS321 of the Korean Industrial Standard (KS) (or selected from the Japanese Industrial Standard (JIS) SUS301, SUS304, SUS305, SUS316L, or SUS321). Either one may be used, but the present invention is not limited to these industrial standards.

The porous outer layer 112 is coated or laminated with a thin thickness on the first surface 111a of the metal plate 111. In addition, the porous outer layer 112 is formed to a thickness of 5 ~ 10㎛. When the thickness of the porous outer layer 112 is 5 μm or less, the heat dissipation performance is not very good. When the thickness of the porous outer layer 112 is 10 μm or more, drawing or folding is not easy during the manufacturing process. In addition, the porous outer layer 112 may be formed using any one selected from a thermally conductive polymer, a thermally conductive elastomer, a thermally conductive silicone elastomer, or an equivalent thereof, which is an electrical insulator and thermally a conductor. It is not intended to limit the invention. In addition, the porous outer layer 112 may be formed of a mixture of a ceramic resin and an adhesive resin, which is an electrically insulator and thermally a conductor. Therefore, the porous outer layer 112 may be coated with a desired thickness on the first surface 111a of the metal plate 111. Of course, after coating the porous outer layer 112 is preferably heat-treated at a predetermined temperature (about 150 ~ 200 ℃). Furthermore, instead of the coating method, the porous outer layer 112 may be manufactured in a sheet form and laminated while applying heat to the first surface 111a of the metal plate 111.

On the other hand, the ceramic powder is any one selected from aluminum oxide (Al ₂ O ₃ ), aluminum nitride (AlN), boron nitride (BN), beryllium oxide (BeO), silicon carbide (SiC) or equivalents having an average particle diameter of several micrometers It may be one, but the type of the ceramic powder is not limited thereto. In addition, the content of the ceramic powder in the adhesive resin may be adjusted to 5 to 50% by volume. When the content is 5 vol% or less, the heat dissipation performance cannot be sufficiently improved, and when the content is 50 vol% or more, the adhesive strength with the metal plate 111 can be weakened. When the content of the ceramic powder is in the above-described range, the heat dissipation performance of the porous outer layer 112 may be stably improved, and the adhesive strength of the metal plate 111 may be maintained well.

The modified polypropylene 113 is coated or laminated on the second surface 111b of the metal plate 111 to a thickness of approximately 30 to 40 μm. The modified polypropylene 113 may be formed to be slightly thicker than the thickness of the metal plate 111 because the electrode assembly (not shown in the drawing) and the like are in direct contact with each other and are thermally fused together.

2 is a perspective view illustrating a state in which a battery exterior material is processed in a predetermined form to accommodate and seal an electrode assembly, an electrolyte, and the like in a battery exterior material in which a porous outer layer is formed according to an exemplary embodiment of the present invention.

As illustrated in FIG. 2, the above-described battery exterior material 100 may be divided into a first region 114 and a second region 115, which are folded and thermally fused to each other. In the first region 114, a drawing unit 116 having a predetermined width and depth may be further formed to accommodate an electrode assembly (not illustrated) having a separator interposed between the plurality of positive electrode plates and the negative electrode plates. . Of course, the drawing part 116 may also be formed in the second region 115. In order to prevent the battery exterior member 110 from being damaged during the formation of the drawing unit 116, the thickness of the battery exterior member 110, that is, the metal plate 111, which is a main material, should be at least 20 μm as described above. Here, the side portion formed on both sides of the drawing portion 116, the modified polypropylene 113 is heat-sealed and folded in a predetermined direction is defined as the side folding portion 117, and the front of the drawing portion 116 The front planar portion 118 defines a region formed in the region where the positive temperature element 131 and the protection circuit board 130 are located.

In addition, the drawing part 116 is formed while the modified polypropylene 113 is in direct contact with the mold. Therefore, as described above, the battery packaging material 110 may have a thickness formed in the order of modified polypropylene 113> metal plate 111> porous outer layer 112.

3A is a perspective view illustrating a state in which a positive temperature device and a protection circuit board are electrically connected to a tab in a lithium polymer battery according to an exemplary embodiment of the present invention, and FIG. 3B is a view in which the positive temperature device and the protection circuit board are electrically connected. 4 is a perspective view illustrating a bent state, and FIG. 4 is a cross-sectional view taken along line 2-2 of FIG. 3B. Here, for convenience of description, the above-described FIGS. 3A, 3B, and 4 will be referred to together.

The lithium polymer battery according to the exemplary embodiment of the present invention is mounted on a battery outer shell 110 having a porous outer layer 112, an electrode assembly 120 embedded in the battery outer shell 110, and a surface of the battery outer shell 110. The protection circuit board 130 is electrically connected to the electrode assembly 120.

First, the battery packaging material 110 has a porous outer layer 112 formed on one surface of the metal plate 111 and a modified polypropylene 113 formed on the other surface thereof. Of course, since the detailed layer structure of the metal plate 111, the porous outer layer 112 and the modified polypropylene 113 has already been described in detail above, it will be omitted here.

In addition, as described above, the battery packaging material 110 includes a first region 114 having a drawing portion 116 formed at a predetermined depth, and a second region 115 covering the drawing portion 116. In addition, the drawing unit 116 is heat-sealed with the side assembly 117 of the outer periphery of the drawing unit 116 while the electrode assembly 120 is seated. Of course, the portion that is actually heat-sealed is the modified polypropylene 113. Then, the heat-sealed portion is folded to one side during the manufacturing process, so that the volume occupied by the battery packaging material 110 is minimized. Here, FIG. 3A illustrates a side folding part 117 of the battery packaging material 110 not yet folded.

On the other hand, the electrode assembly 120 is provided with a plurality of positive electrode plate 121 and the negative electrode plate 123 through the separator 122, and extends a predetermined length outward from the positive electrode plate 121 and the negative electrode plate 123 The positive electrode tab 124 and the negative electrode tab 125 are connected to each other. In addition, the positive electrode tab 124 and the negative electrode tab 125 further extend a predetermined length to the outside of the battery packaging material 110. That is, the predetermined length is further extended to the outside of the front flat portion 118 described above. Here, the positive electrode tab 124 may be formed of ordinary aluminum, and the negative electrode tab 125 may be formed of ordinary nickel, but the present invention is not limited thereto.

The protective circuit board 130 is electrically connected to the negative electrode tab 125 (or the positive electrode tab 124) via the positive temperature element 131. In addition, the positive electrode tab 124 (or negative electrode tab 125) is directly connected to the protective circuit board 130. Of course, the positive temperature element 131 may be directly installed inside the protection circuit board 130, and the connection portion of the positive temperature element 131 is not limited thereto.

Meanwhile, in this state, the positive electrode tab 124 and the negative electrode tab 125 are bent several times so that the protective circuit board 130 is positioned on the front flat portion 118 described above, so that the volume of the battery 100 is minimized. It is. That is, in the cross-sectional structure, the positive electrode tab 124 and the negative electrode tab 125 are bent once on the front flat part 118, and the positive temperature is on the negative electrode tab 125 (or the positive electrode tab 124). Element 131 is located. Of course, a portion of the positive temperature element 131 is in direct contact with the front flat portion 118, thereby being sensitive to the heat generation phenomenon generated from the battery packaging material 110 having a porous outer layer 112. have. In addition, a protective circuit board 130 is positioned on the positive electrode tab 124, the negative electrode tab 125, and the positive temperature element 131. In addition, the positive electrode tab 124 and the negative electrode tab 125 may be bent a plurality of times, and the ends thereof may be electrically connected to the upper surface of the protective circuit board 130. Of course, the battery packaging material 110 has a porous outer layer 112 formed on the outermost surface, thereby improving heat dissipation performance and rapidly transferring heat to the positive temperature device 131, thereby providing a positive temperature device ( 131) to improve the reactivity. Furthermore, the porous outer layer 112 formed on the surface of the battery packaging material 110 has a high mechanical strength and excellent corrosion resistance and impact resistance, thereby further improving the reliability of the lithium polymer battery 100.

5A to 5E are sequential diagrams illustrating a method of manufacturing a lithium polymer battery according to an embodiment of the present invention.

First, as illustrated in FIG. 5A, a battery exterior member 110 of a predetermined type is manufactured. That is, the battery packaging material includes a first region 114 having a drawing unit 116 having a size to accommodate an electrode assembly (not shown), and a second region 115 covering the first region 114. 110 is prepared. Of course, both side portions of the first region 114 and the second region 115 are formed with side folding parts 117 which are subsequently heat-sealed, and the front flat portion where the protective circuit board 130 to be described below is located. 118 is formed.

In addition, the battery packaging material 110 includes a substantially plate-shaped metal plate 111, a porous outer layer 112 formed on one surface of the metal plate 111, and a modified polypropylene 113 formed on the other surface of the metal plate 111. It has a layer structure. Of course, the porous outer layer 112 to increase the heat dissipation performance and mechanical strength, and also to be the outer surface of the battery packaging material 110 to improve the reactivity of the positive temperature element 131. In addition, since the detailed layer structure of the battery outer packaging material 110 has been described in detail in the above description of the battery packaging material 110, it will be omitted here.

Subsequently, as illustrated in FIG. 5B, the electrode assembly 120 is accommodated in the drawing part 116 formed in the first region 114 of the battery packaging material 110. That is, the electrode assembly 120 having the positive electrode tab 121, the separator 122, and the negative electrode plate 123 wound up a plurality of times, and having a positive electrode tab 124 and a negative electrode tab 125 extending in a predetermined length toward the front side is a battery. It is accommodated in the drawing part 116 of the exterior material 110. Of course, the positive electrode tab 124 and the negative electrode tab 125 are extended to a predetermined length outward through the front flat portion 118 of the battery packaging material 110.

Subsequently, as shown in FIG. 5C, the protective circuit board 130 is electrically connected to the positive electrode tab 124 and the negative electrode tab 125 of the electrode assembly 120. In this case, the positive temperature element 131 is electrically connected between the negative electrode tab 125 (or the positive electrode tab 124) and the protective circuit board 130. As described above, the positive temperature element 131 serves to reduce or cut off the flow of current by quickly detecting this when the battery generates heat.

Subsequently, as shown in FIG. 5D, the protective circuit board 130 is seated on the front flat portion 118 of the battery packaging material 110. In this case, the positive electrode tab 124 and the negative electrode tab 125 are bent many times. That is, since the positive electrode tab 124 and the negative electrode tab 125 are bent once, the positive electrode tab 124, the negative electrode tab 125, and the positive temperature element 131 are first positioned on the front flat portion 118. . Of course, by attaching a thermally conductive tape that is electrically insulator and thermally conductive to the surface of the front flat portion 118, it is possible to improve heat transfer to the positive temperature element 131, but this is a limitation of the present invention. It is not. Thereafter, the positive electrode tab 124 and the negative electrode tab 125 are bent again, so that the protective circuit board 130 is stably positioned on the front flat portion 118. Moreover, even if a thermally conductive adhesive tape or the like is positioned between the protective circuit board 130 and the front flat portion 118, the adhesion state may be further improved.

Lastly, as shown in FIG. 5E, the side folding part 117 of the battery packaging material 110 is bent upward, thereby completing the manufacture of the lithium polymer battery according to the present invention. Of course, the size of the battery 100 is minimized due to the folding of the side folding part 117. In addition, since the inside of the metal plate 111 is exposed to the outside through the folding part 117, it can be sealed with an insulating member to prevent such exposure, but this is not limiting the present invention. .

As described above, the battery envelope having the porous outer layer according to the present invention and the lithium polymer battery using the same have a porous outer layer that is electrically insulating and thermally conductive on the surface of the battery envelope, thereby providing charge and discharge of the battery. Medium heat dissipation performance is maximized, thereby improving the life and reliability of the battery.

In addition, the present invention is that the positive temperature element electrically connected between the electrode assembly and the protective circuit board is in direct contact with the above-described porous outer layer, thereby immediately detecting this when the battery heats to block or reduce the current flow, The reliability is greatly improved.                     

In addition, the present invention also has an effect that the porous outer layer is formed on the surface of the battery packaging material, thereby improving mechanical strength, corrosion resistance, impact resistance, moldability, adhesion to other members, and the like.

Claims (21)

A metal plate having a first substantially flat surface and a second substantially flat surface opposite thereto; A porous outer layer formed to a predetermined thickness on the first surface of the metal plate; And, Battery exterior material comprising a modified polypropylene (CPP) formed in a predetermined thickness on the second surface of the metal plate. The method of claim 1, wherein the metal plate is an alloy of iron (Fe), carbon (C), chromium (Cr) and manganese (Mn), iron (Fe), carbon (C), chromium (Cr) and nickel (Ni) The battery packaging material, characterized in that any one selected from the alloy, or aluminum (Al). The battery packaging material according to claim 1, wherein the porous outer layer is electrically insulating. The battery case of claim 1, wherein the porous outer layer is any one selected from a thermally conductive polymer, a thermally conductive elastomer, and a thermally conductive silicone elastomer. According to claim 1, wherein the porous outer layer is a battery packaging material, characterized in that formed by mixing a ceramic powder and an adhesive resin. The method of claim 5, wherein the ceramic powder is any one selected from aluminum oxide (Al ₂ O ₃ ), aluminum nitride (AlN), boron nitride (BN), beryllium oxide (BeO) or silicon carbide (SiC). Battery exterior material to say. 6. The battery packaging material according to claim 5, wherein the porous outer layer has a content of 5 to 50% by volume of ceramic powder. According to claim 1, wherein the porous outer layer is a battery packaging material, characterized in that the thickness of 5 ~ 10㎛. According to claim 1, wherein the battery packaging material comprises a first region having a drawing portion of a predetermined depth so that the electrode assembly can be accommodated, and a second region starting to fold at one end of the first region to cover the drawing portion A battery exterior material, characterized in that. 10. The battery packaging material according to claim 9, wherein the battery packaging material is a modified polypropylene corresponding to the outer circumference of the drawing part among the first region and the second region, which is bonded to each other by heat fusion bonding. An electrode assembly having a plurality of positive electrode plates and a negative electrode plate provided through a separator, and having a positive electrode tab and a negative electrode tab connected to the outside by a predetermined length from the positive electrode plate and the negative electrode plate; And A first region having a drawing portion having a predetermined depth is provided to accommodate the electrode assembly, and includes an exterior material having a porous outer layer provided with a second region to cover the drawing portion of the first region. The exterior material, A metal plate having a first substantially flat surface and a second substantially flat surface opposite thereto; And Lithium polymer battery comprising a modified polypropylene (CPP) formed in a predetermined thickness on the second surface of the metal plate. The method of claim 11, wherein the packaging material And a porous outer layer formed to a predetermined thickness on the first surface of the metal plate. The method of claim 12, wherein the metal plate is an alloy of iron (Fe), carbon (C), chromium (Cr) and manganese (Mn), iron (Fe), carbon (C), chromium (Cr) and nickel (Ni) Lithium polymer battery, characterized in that any one selected from an alloy, or aluminum (Al). 12. The lithium polymer battery of claim 11, wherein the porous outer layer is electrically insulating. 12. The lithium polymer battery of claim 11, wherein the porous outer layer of the packaging material is any one selected from a thermally conductive polymer, a thermally conductive elastomer, and a thermally conductive silicone elastomer. 12. The lithium polymer battery of claim 11, wherein the porous outer layer is formed by mixing a ceramic powder and an adhesive resin. The method of claim 16, wherein the ceramic powder is any one selected from aluminum oxide (Al ₂ O ₃ ), aluminum nitride (AlN), boron nitride (BN), beryllium oxide (BeO) or silicon carbide (SiC). Lithium polymer battery. The lithium polymer battery of claim 16, wherein the porous outer layer has a content of 5 to 50% by volume of ceramic powder. The method of claim 11, wherein the porous outer layer is a lithium polymer battery, characterized in that the thickness of 5 ~ 10㎛. The method of claim 11, wherein the positive electrode tab and the negative electrode tab is electrically connected to the protective circuit board, the positive temperature element between the negative electrode tab and the protective circuit board is further interposed on the surface of the battery casing is further interposed. A lithium polymer battery. 12. The lithium polymer battery according to claim 11, wherein the battery packaging material is a modified polypropylene corresponding to the outer circumference of the drawing portion among the first region and the second region, which is bonded to each other by thermal fusion bonding.

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