TWM507349U - Battery shell structure - Google Patents

Description

Battery shell structure

This creation relates to a battery shell structure, in particular to a battery shell structure that enhances shielding and safety.

Lithium batteries are widely used in power supply sources such as notebook computers, mobile phones, digital cameras, and electric vehicles. With the increasing design of electronic devices, the battery is thinned to reduce its volume. Further, the design for reducing the occupied space has been paid more and more attention, and a battery-shell structure of a composite film type formed by a laminated structure has been developed.

The conventional battery structure includes an outer casing and a positive electrode layer, a negative electrode layer, a separator and an electrolyte encapsulated inside the outer casing, the separator is disposed between the positive electrode layer and the negative electrode layer, and the electrolyte is used for The positive electrode layer and the negative electrode layer are immersed. In order to reduce the thickness of the battery shell layer, the prior art is to coat the aluminum foil layer with a polyimide film to form a conventional battery shell structure. However, if the battery used is overheated due to improper operation and its temperature rises rapidly, it may cause the battery to burst. In addition, due to external force, the battery aluminum foil is broken, and it is easy to react inside, thereby generating and releasing oxygen, carbon dioxide or other gases, so that the battery shell adsorbs gas to expand and reduce the service life of the battery.

Therefore, in view of the above-mentioned various shortcomings, how to improve security The battery shell structure with increased service life has become a difficult problem to be overcome in the industry.

The present invention provides a battery shell structure comprising: at least one inner coating layer; a gas barrier layer formed on the inner coating layer; a radical formed on the gas barrier layer to capture an adhesive layer, and the radical capture The layer includes an adhesive and a radical scavenger; and a protective layer formed on the radical trapping layer, the radical trapping layer being interposed between the gas barrier layer and the outer protective layer.

In one embodiment, the content of the radical scavenger is from 0.5 to 10% based on the total weight of the radical scavenging adhesive layer, and the adhesive is selected from the group consisting of polyurethane resins, polyester resins, and pressure. Made of crepe resin or polyolefin resin.

In one embodiment, the free radical trapping layer has a thickness between 3 and 5 microns. In the foregoing embodiment, the radical scavenger is made of a compound for providing free hydrogen. For example, the radical scavenger is an aromatic ring structure compound having a hydroxyl group, and the compound has hydrogen for free, 俾It is combined with a free radical to convert the compound into a resonance mixture or a resonance compound. In a preferred embodiment, the radical scavenger is selected from the group consisting of phenol, N, N'-bis(2-naphthyl)-p-phenylenediamine, 4,4'-thiobis (6-tert-butyl) Phenol), tris(butylcresolyl)butane, tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoic acid]pentaerythritol ester, 2,6-di-tert-butyl-p-cresol and A material made of at least one of the group consisting of Barbituric Acid.

In one embodiment, the outer protective layer has a thickness of 10 to 50 microns. The outer protective layer comprises a first polymer and a colorant, wherein the toner is contained in an amount of 10 to 25% based on the total weight of the outer protective layer. In the above embodiment, the first polymer is selected from the group consisting of an epoxy resin, an acrylic resin, a urethane resin, a ruthenium rubber resin, a polyparaxylene resin, and a bismaleimide system. At least one of a group consisting of a resin and a polyimide resin.

In one embodiment, the outer protective layer further comprises a radical scavenger, and the content of the radical scavenger is from 0.5 to 10% based on the total weight of the outer protective layer.

In one embodiment, the battery shell structure includes a heat resistant layer formed between the gas barrier layer and the radical trapping layer.

In the battery shell structure of the present invention, the toner is selected from at least one of the group consisting of carbon materials, pigments, dyes, and toners.

In a specific embodiment, the thickness of the inner cover layer is between 30 and 100 micrometers, and the inner cover layer is made of a polyolefin. In a preferred embodiment, the polyolefin is selected from the group consisting of polyethylene and polypropylene. At least one of the group consisting of polybutene and polypentene.

In one embodiment, the inner cover layer is a plurality of layers, wherein the material forming each of the inner cover layers is independently selected from the group consisting of polyethylene, polypropylene, polybutene, and polypentene. One. The material of the inner cover layer is independently selected from the group consisting of polyethylene, polypropylene, polybutene or polypentene.

In one embodiment, the gas barrier layer 12 has a thickness of 30 to 50 microns, wherein the gas barrier layer is an aluminum foil layer.

It can be seen from the above that the battery shell structure of the present invention, when the battery is suddenly increased or overheated due to improper use or abnormality, the radical trapping agent is added by the radical trapping layer to be higher than 120. At a temperature of °C, a melting state is generated to release a radical scavenger, so that a radical scavenger can rapidly capture the gas released by the high temperature before the explosion, thereby blocking the combustion reaction to reduce the possibility of combustion. Thereby improving the safety of the battery. Furthermore, the barrier property of the battery can be improved by capturing the adhesive layer with a radical having a toner.

Therefore, the battery shell structure of the present invention not only improves the safety of the battery, but also prolongs the service life of the battery and improves the shielding property of the battery.

1,1', 2‧‧‧ battery shell structure

12‧‧‧ inner cladding

13‧‧‧First adhesive layer

14‧‧‧Gas barrier

15‧‧‧Second adhesive layer

16‧‧‧Heat resistant layer

17‧‧‧Free radical capture layer

18, 18’‧‧‧ outer protective layer

1 is a schematic cross-sectional view showing a first embodiment of a battery case structure of the present invention, wherein FIG. 1A is a schematic cross-sectional view showing another embodiment of the battery case structure of the first embodiment; Fig. 2 is a schematic cross-sectional view showing a second embodiment of the battery case structure of the present invention.

The embodiments of the present invention are described below by way of specific embodiments, and those skilled in the art can readily appreciate other advantages and functions of the present invention from the disclosure of the present disclosure.

It is to be understood that the structure, the proportions, the size and the like of the drawings are only used in conjunction with the disclosure of the specification for the understanding and reading of those skilled in the art, and are not intended to limit the implementation of the present invention. The qualifications are not technically meaningful, the modification or proportion of any structure Changes in the relationship or adjustment of the relationship should not fall within the scope of the technical content disclosed in this creation without affecting the effectiveness of the creation and the purpose for which it can be achieved. In the meantime, the terms "one", "two", "first", "second" and "upper" as used in this specification are for convenience only, and are not intended to limit the scope of the creation of the creation. Changes or adjustments in their relative relationship are considered to be within the scope of the creation of the creation of the product without substantial changes.

First embodiment

1 is a schematic cross-sectional view of a first embodiment of a battery shell structure 1 of the present invention. The battery shell structure 1 includes an inner cladding layer 12, a gas barrier layer 14, and a free radical. The adhesive layer 17 and the outer protective layer 18 are captured.

In the embodiment, the inner cover layer 12 and the gas barrier layer 14 further include a first adhesive layer 13 to adhere the inner cover layer 12 to the gas barrier layer 14.

In the present embodiment, the radical scavenging adhesive layer 17 comprises an adhesive and a radical scavenger. The above-mentioned radical scavenger is made of a compound for providing free hydrogen, wherein a compound having an aromatic ring main structure having a hydroxyl group is preferred, and the compound has free hydrogen, free and free. Substituting, converting the compound into a resonance mixture or a resonance compound, but examples of having a hydrogen donor include phenol, N, N'-bis(2-naphthyl)-p-phenylenediamine, 4,4'-sulfur Bis(6-tert-butyl m-cresol), tris(butylcresolyl)butane, tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoic acid]pentaerythritol ester, 2, 6-di-tert-butyl-p-cresol and Barbituric Acid, etc., which may be selected from materials of at least one of the group consisting of.

In a preferred embodiment, the amount of the radical scavenger is from 0.5 to 10% based on the total weight of the radical scavenging backing layer. The addition of the free radical scavenger can be accomplished by blending and the free radical scavenging layer is prepared using conventional film forming techniques.

The adhesive is selected from the group consisting of a polyurethane resin, a polyester resin, an acrylic resin, or a polyolefin resin. The aforementioned radical scavenging adhesive layer has a thickness of 3 to 5 μm.

Furthermore, in another embodiment of the present invention, the radical trapping adhesive layer 17 contains a coloring agent selected from at least one selected from the group consisting of carbon materials, pigments, dyes, and toners. The free radical captures the total weight of the layer 17, which is present in an amount between 10 and 25%.

In the present embodiment, the material of the first adhesive layer 13 may be an adhesive material such as a urethane resin, a polyester resin, an acryl resin, or a polyolefin resin. Typically, the first adhesive layer 13 has a thickness of 3 to 5 microns.

The gas barrier layer 14 is made of metal. In the preferred embodiment, the gas barrier layer 14 is an aluminum foil. In addition, the gas barrier layer has a thickness of 30 to 50 micrometers, and has a good gas barrier effect.

In the present embodiment, the material of the inner cladding layer 12 is usually a polyolefin, and the flexibility and coating properties of the crucible are used as a contact encapsulation layer. For example, the polyolefin is at least one of the group consisting of polyethylene, polypropylene, polybutene, and polypentene.

In addition, the inner cover 12 is configured to have at least one layer of single, double or triple layers to improve the corrosion resistance of the inner cover 12 and the protection of the gas barrier layer 14 when the inner cover layer is When 12 is two or more layers, each of them is formed. The material of the inner cover 12 is independently selected from at least one of the group consisting of polyethylene, polypropylene, polybutene, and polypentene.

In this embodiment, the outer protective layer 18 has a thickness of 10 to 50 micrometers, and is composed of a first polymer and a coloring agent. The total amount of the coloring agent is determined by the total weight of the outer protective layer. 10 to 25%. The first polymer is selected from the group consisting of polyamine, epoxy resin, acrylic resin, urethane resin, ruthenium rubber resin, polyparaxylene resin, and bismaleimide resin. At least one of the group consisting of polyimine resins. The coloring agent is selected from at least one of the group consisting of carbon materials, pigments, dyes, and toners. For example, in the foregoing embodiment, the outer protective layer 18 is a colored polyimide film or a polyester film (such as a polycarbonate film) or a polyimide film.

Further, in another embodiment of the battery case structure 1' of the present invention, the radical scavenger may be added to the outer protective layer 18'. The content of the radical scavenger is from 0.5 to 10% based on the total weight of the outer protective layer, as shown in Fig. 1'.

Second embodiment

Referring to FIG. 2, it is a schematic cross-sectional view of the battery shell structure 2 of the present invention. The difference from the battery shell structure 1 of the first embodiment is that the battery shell structure 2 includes a heat-resistant layer 16 and is formed. Between the gas barrier layer 14 and the radical trapping adhesion layer 17.

In this embodiment, the heat-resistant layer 16 is adhered to the gas barrier layer 14 through the second adhesive layer 15 , and the heat-resistant layer 16 is sandwiched between the radical capturing adhesive layer 17 and the second adhesive layer 15 . .

The heat-resistant layer 16 is a structure having a thickness of 10 to 50 μm and is made of polyamine, polyester, or polyamine.

Embodiment 1 Preparation of Battery Shell Structure of First Embodiment of Present Creation

The battery shell structure 1 includes a polypropylene film (South Asia, CXDA) having a thickness of 40 micrometers (μm) as an inner coating layer 12, and a polyurethane resin (Asia Electric Materials Co., Ltd., model AEM) on the inner coating layer 12. -A1) forming a first adhesive layer 13 having a thickness of 4 μm , using a 40 μm thick aluminum foil as the gas barrier layer 14, and forming a 4 μm thick radical capturing adhesive layer 17 on the gas barrier layer 14, wherein The radical scavenging adhesive layer 17 comprises a polyurethane resin (Asia Electric Materials, Model AEM-A1) and 3% of the radical scavenger (N, N'-di (by total weight of the radical scavenging layer 17). 2-naphthyl)p-phenylenediamine, Tianqing Chemical, model anti-aging agent DNP), and a nylon film with a thickness of 25 μm containing 15% by weight of carbon black (CABOT BLACK PEARLS® 570) (Yuniji, model EMBLEM 25) As the outer protective layer 18, the battery can structure 1 of the first embodiment was obtained.

Embodiment 2 Preparation of Battery Shell Structure of the First Embodiment of the Creation

The same as the preparation method of Embodiment 1, the difference is only in the battery shell structure 1' of Embodiment 2, and the outer protective layer 18' includes the carbon black of 15% by total weight of the outer protective layer 18'. (CABOT BLACK PEARLS® 570), and 3% of free radical scavenger (N, N'-bis(2-naphthyl)-p-phenylenediamine, Tianqing Chemical's black ink film with thickness of 5μm (Toyo Ink, FDO) NEW) as the outer protective layer 18'.

Embodiment 3 Preparation of Battery Shell Structure of the First Embodiment of the Creation

The same as the preparation method of the first embodiment, the difference is only in the third embodiment. In the battery shell structure 1, the radical trapping layer 17 further comprises 10% carbon black (CABOT BLACK PEARLS® 570) based on the total weight of the radical trapping layer 17.

Embodiment 4 Preparation of Battery Shell Structure of Second Embodiment of Present Creation

The same as the preparation method of the first embodiment, the difference is only in the battery shell structure 2 of the embodiment 4, which is bonded to the gas barrier layer 14 by a polyurethane resin (Asia Electric Materials Co., Ltd., model AEM-A1). Heat-resistant layer 16 of nylon material (Uniczico, model EMBLEM 25) having a thickness of 25 μm.

Comparative example 1

The structure of the battery shell of Example 1 was the same as that of the method of manufacture, except that no radical scavenger was added to each layer structure.

Test case

The battery shell structure described in the foregoing Examples 1 to 4 and Comparative Example 1 was punched and formed into a shell by a punching machine to form an outer casing of 5.0 cm long, 3.7 cm wide, and 0.5 cm thick for encapsulating the lithium ion electrolyte. According to the specification of 503759 model, the lithium ion electrolyte is filled in the potting solution, and the packaging process is performed to constitute a lithium battery, and the prepared battery is activated by charging at 4.2V, and then the average electric capacity is measured at a 0.2 C discharge rate. 1274mAh.

The 503759 type battery prepared according to the embodiment was subjected to a puncture test, and the thermocouple thermometer was embedded in a nail for use in the puncture experiment, thereby performing a puncture test to measure the battery short-circuit point temperature, and the result is recorded in Table 1. .

As shown in Table 1, the battery shell structure of the present invention enhances the safety of the battery case by using the radical scavenging adhesive layer of the radical scavenger, and reduces the temperature of the battery short-circuit point during puncture, but if the free radical is not used In the capture layer, the battery short-circuit point temperature will be greater than 500 ° C, and it will not pass the puncture test.

Further, the 503759 type battery prepared by the battery shell structure prepared in Examples 1 to 4 and Comparative Example 1 was cut into sample pieces of appropriate size for the test of brightness and gloss, and The test results are reported in Table 2.

The test methods used in the test examples are as follows: Gloss test: using a gloss tester (Omega, Germany; model micro-gloss 60°), according to the ASTM D1003 instrument method, that is, at the light incident angle The gloss of the machine direction (MD) was measured under conditions of 60°.

Lightness test: using a color difference tester (KONICA MINOLTA; model CM2500d), according to ASTM D2244 instrument The method was tested, that is, the brightness of the machine direction (MD) was measured under the condition that the light incident angle was 45°.

The term "gloss" as used herein means the degree of reflection of the surface of the sheet to be tested. The gloss does not have a unit, but the larger the value, the stronger the intensity of the reflected light. Conversely, the smaller the value, the reflection. The weaker the intensity of light. The term "lightness" as used herein is defined by the International Commission on Illumination for the degree of color shading (usually, white has the highest brightness; black has the lowest brightness). Therefore, the lower the brightness, the better the effect of shielding the line.

From the results of the above test examples, it was found that the first radical scavenging adhesive layer and the second radical scavenging adhesive layer having color concealing properties were transmitted to enhance the shielding property of the battery can.

In summary, in the battery shell structure of the present invention, when the battery is suddenly increased or overheated due to improper use or abnormality, the free radical trapping layer on the outer side of the battery shell has When the temperature is higher than 120 °C, it will melt and release the characteristics of the radical scavenger. Before the explosion, the free radical trapping agent can quickly capture the gas released by the high temperature, thereby blocking the combustion reaction to reduce the combustion. It is possible to avoid the situation in which the gas adsorbs the layers to cause the generated battery to expand, thereby improving the safety of the battery.

Furthermore, by having a protective layer other than color shielding and/or a radical capturing adhesive layer, it is not only necessary to improve the protective shielding property of the battery, but also to accelerate the discharge of thermal energy generated by improper operation to the external environment. This lowers the internal temperature of the battery and therefore has the effect of increasing the thermal conductivity of the battery.

Therefore, the battery shell structure of the present invention not only improves the safety of the battery, but also increases the shielding property and thermal conductivity of the battery, thereby prolonging the service life of the battery.

The above-described embodiments are merely illustrative of the effects of the present invention and are not intended to limit the present invention. Any person skilled in the art can implement the above-described embodiments without departing from the spirit and scope of the present invention. Make modifications and changes. In addition, the number of elements in the above-described embodiments is merely illustrative and is not intended to limit the present invention. Therefore, the scope of protection of this creation should be as listed in the scope of patent application described later.

1‧‧‧Battery shell structure

12‧‧‧ inner cladding

13‧‧‧First adhesive layer

14‧‧‧Gas barrier

17‧‧‧Free radical capture layer

18‧‧‧ outer protective layer

Claims (21)

A battery shell structure comprising: at least one inner coating layer; a gas barrier layer formed on the inner coating layer; a radical trapping adhesion layer formed on the gas barrier layer, and the radical trapping layer And comprising an adhesive and a radical scavenger; and an outer protective layer formed on the radical scavenging adhesive layer, the free radical trapping layer being interposed between the gas barrier layer and the outer protective layer. The battery shell structure of claim 1, wherein the radical trapping layer has a thickness of between 3 and 5 microns. The battery shell structure of claim 1, wherein the radical scavenger is present in an amount of from 0.5 to 10% based on the total weight of the radical scavenging adhesive layer. The battery shell structure according to claim 1, wherein the adhesive is selected from the group consisting of polyurethane resins, polyester resins, acrylic resins, and polyolefin resin. The battery shell structure of claim 1, wherein the outer protective layer comprises a first polymer and a coloring agent. The battery shell structure of claim 5, wherein the toner is contained in an amount of 10 to 25% based on the total weight of the outer protective layer. Such as the battery shell structure of claim 5, wherein the outer The protective layer further comprises a radical scavenger, and the content of the radical scavenger is from 0.5 to 10% based on the total weight of the outer protective layer. The battery shell structure of claim 5, wherein the first polymer is selected from the group consisting of polyamine, epoxy resin, acrylic resin, urethane resin, ruthenium rubber resin, and poly pair. At least one of a group consisting of a cycloxylene resin, a bismaleimide resin, and a polyimide resin. The battery shell structure of claim 8, wherein the outer protective layer has a thickness of 10 to 50 μm. The battery shell structure of claim 1, wherein the radical trapping layer further comprises a coloring agent, and the toner is contained in an amount of 10 to 25% based on the total weight of the radical trapping layer. . The battery shell structure of claim 1, wherein the heat-resistant layer is formed between the gas barrier layer and the radical trapping layer. The battery shell structure of claim 5 or 10, wherein the coloring agent is selected from at least one of the group consisting of carbon materials, pigments, dyes, and toners. The battery shell structure of claim 1, wherein the radical scavenger is made of a compound for providing free hydrogen. The battery shell structure of claim 13, wherein the compound is an aromatic ring structure compound having a hydroxyl group. The battery shell structure of claim 14, wherein the radical scavenger is selected from the group consisting of phenol, N, N'-bis(2-naphthyl)-p-phenylenediamine, 4,4'-thio Bis(6-tert-butyl m-cresol), tris(butyl cresyl) butane, Group of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoic acid] pentaerythritol ester, 2,6-di-tert-butyl-p-cresol and barbituric acid Made of at least one of the materials. The battery shell structure of claim 1, wherein the inner layer has a thickness of 30 to 100 μm. The battery shell structure of claim 16, wherein the inner layer is made of a polyolefin. The battery shell structure of claim 17, wherein the polyolefin is at least one selected from the group consisting of polyethylene, polypropylene, polybutene, and polypentene. The battery shell structure of claim 1, wherein the gas barrier layer is an aluminum foil layer. The battery shell structure of claim 1, wherein the gas barrier layer has a thickness of 30 to 50 μm. The battery shell structure of claim 1, wherein the outer protective layer has a thickness of 10 to 50 μm.