TWM517094U - Packaging film for battery for electrical performance test - Google Patents

Abstract

A packaging film for battery for electrical performance test is provided. The packaging film for battery includes an aluminum foil layer, a first adhesive layer, a polyolefin sealant layer, a second adhesive layer, a heat resistant resin layer and a heat sensing layer. The first adhesive layer is disposed on a surface of the aluminum foil layer. The polyolefin sealant layer is attached on the aluminum foil layer by the first adhesive layer. The second adhesive layer is disposed on another surface of the aluminum foil layer opposite to the first adhesive layer. The heat resistant resin layer is attached on the aluminum foil layer by the second adhesive layer. The heat sensing layer is disposed on a surface of the heat resistant resin layer. The packaging film for battery can simplify the procedure of the electrical performance test of a battery and increase the reliability of the electrical performance test.

Description

Battery packaging film for battery electrical testing

This creation relates to a battery packaging film, and in particular to a battery packaging film that can be used for battery electrical testing.

The battery is manufactured by packaging the battery core with a battery packaging film, followed by heat sealing treatment and filling of the electrolyte, and finally completing the battery after the edge sealing. The finished battery must be electrically tested before leaving the factory.

Secondary batteries, particularly in the technical field of lithium ion secondary batteries, the thermal safety of batteries is very important. When the temperature of the secondary battery increases, the secondary battery is subjected to a heat impact, which adversely affects the constituents of the battery constituting the battery such as an electrolyte or an electrode. Therefore, even if the battery subjected to the overheating shock can continue to be used, the battery may have a safety risk and may have a high risk of explosion or combustion. Although the battery with thermal shock can still be used, it is very important to check whether the battery has been subjected to overheating in the past for the performance and safety of the battery. Moreover, the history of thermal shock of the battery is also closely related to the life of the battery.

Therefore, the completed battery is electrically tested before leaving the factory. In addition to the need to test the battery capacity during charging and discharging, it is also necessary to monitor the surface temperature of the battery during charging and discharging. During the rapid charge and discharge process, the temperature of the battery will rise significantly. When the surface temperature is higher than 60 °C, the battery life is short. When the surface temperature is higher than 70 °C, the battery is short-circuited. Therefore, when performing charge and discharge test, If the temperature of the battery body area exceeds 60 °C, it should be regarded as a defective product.

The conventional temperature monitoring method during battery charging and discharging measures a certain point in the center of the battery with a temperature sensor. Since each factory battery must be tested for charge and discharge at least once, the temperature sensor's assembly and disassembly time, procurement and maintenance costs will increase the time cost of production, and the conventional temperature detection method only measures the battery. Measuring the temperature of the point, the battery product can not be comprehensively observed, in addition, the inspection and labeling of the defective product requires labor to complete to ensure the quality and safety of the product.

Therefore, there is still a need for a battery packaging film for battery electrical testing to solve the aforementioned problems.

The present invention provides a battery packaging film for battery electrical testing. The battery packaging film of the present invention simplifies the electrical testing process of the battery and improves the reliability of the electrical test.

The present invention provides a battery packaging film for battery electrical testing, comprising: an aluminum foil layer; a first adhesive layer disposed on a surface of one of the aluminum foil layers; and a polyolefin sealing layer adhered by the first adhesive layer Attached to the aluminum foil layer; a second adhesive layer disposed on the other surface of the aluminum foil layer relative to the first adhesive layer; a heat resistant resin layer attached to the aluminum foil layer by the second adhesive layer; Take And a thermal sensing layer disposed on a surface of one of the heat resistant resin layers.

In an embodiment of the present invention, the thickness of the aforementioned thermal sensing layer may be between 5 micrometers (μm) and 150 micrometers (μm).

In one embodiment of the present invention, wherein the aforementioned thermal sensing layer indicates three degrees of temperature change.

In an embodiment of the present invention, the heat sensing layer may be formed by coating an irreversible thermochromic ink on the heat resistant resin layer, and the color thereof changes according to temperature, and the changed color does not return to the color. The previous color.

In an embodiment of the present invention, the thermochromic ink has a color tone that varies with temperature.

In an embodiment of the present invention, the thickness of the aforementioned aluminum foil layer is between 10 micrometers (μm) and 100 micrometers (μm).

In an embodiment of the present invention, the thickness of the first adhesive layer is between 0.1 micrometers (μm) and 10 micrometers (μm).

In an embodiment of the present invention, the thickness of the second adhesive layer is between 0.1 micrometers (μm) and 10 micrometers (μm).

In an embodiment of the present invention, the aforementioned polyolefin sealing layer may be a cast polypropylene (CPP) film.

In one embodiment of the present invention, the thickness of the aforementioned polyolefin sealing layer is between 20 micrometers (μm) and 80 micrometers (μm).

In an embodiment of the present invention, the aforementioned heat resistant resin layer may be a polyamide film or a polyester film.

In an embodiment of the present invention, the thickness of the aforementioned heat resistant resin layer is between 9 micrometers (μm) and 50 micrometers (μm).

10‧‧‧Battery packaging film

11‧‧‧Aluminum foil layer

12‧‧‧First adhesive layer

13‧‧‧Polyolefin sealant

14‧‧‧Second Adhesive Layer

15‧‧‧Heat resistant resin layer

16‧‧‧Thermal sensing layer

Fig. 1 is a schematic cross-sectional view showing a battery packaging film according to an embodiment of the present invention.

In order to make the description of the present disclosure more detailed and complete, the following description of the embodiments of the present invention and the specific embodiments are provided for illustrative purposes; however, this is not the only form of implementing or applying the specific embodiments of the present invention. The embodiments disclosed herein may be combined or substituted with each other in an advantageous manner, and other embodiments may be added to an embodiment without further description or description.

In the following description, numerous specific details are set forth However, embodiments of the present invention may be practiced without such specific details. In other instances, well-known structures and devices are only schematically shown in the drawings in order to simplify the drawings.

One of the aims of the present invention is to provide a battery packaging film for battery electrical testing.

Referring to FIG. 1, a cross-sectional view of a battery packaging film 10 for battery electrical testing according to an embodiment of the present invention is shown. The battery packaging film 10 disclosed herein has the advantages of simplifying the electrical test procedure and improving the reliability of the test. As shown in FIG. 1, the battery packaging film 10 includes an aluminum foil layer 11, a first adhesive layer 12, a polyolefin sealing layer 13, a second adhesive layer 14, a heat resistant resin layer 15, and a heat sensing layer 16. The first adhesive layer 12 is disposed on one surface of the aluminum foil layer 11, and the polyolefin sealing layer 13 is attached to the aluminum foil layer 11 by the first adhesive layer 12. The second adhesive layer 14 is disposed on the aluminum foil layer 11 oppositely. On the other surface of the first adhesive layer 12, the heat resistant resin layer 15 is attached to the aluminum foil layer 11 by the second adhesive layer 14, and the heat sensing layer 16 is disposed on one surface of the heat resistant resin layer 15.

The aluminum foil layer 11 is used to provide barrier properties against moisture, oxygen, etc., and is generally made of pure aluminum or a small amount of iron may be added to increase the processability of the aluminum foil layer 11. The thickness of the aluminum foil layer 11 is usually between 10 and 100 micrometers (μm) in order to ensure processability and to prevent airtightness of moisture or oxygen intrusion. If the thickness of the aluminum foil layer 11 is too thin, it is easy to cause the aluminum foil to be broken or pinholes during molding, so that the risk of moisture or oxygen intrusion increases. In contrast, if the thickness of the aluminum foil layer 11 is too thick, only the total thickness of the packaging material becomes thick, the weight increases, and the volume energy density decreases. In one embodiment of the present invention, the material of the aluminum foil layer 11 is a soft aluminum foil containing 2% iron. The aluminum foil layer 11 has a thickness of about 40 micrometers (μm).

Referring to FIG. 1, the first adhesive layer 12 is disposed on one surface of the aluminum foil layer 11. The material of the first adhesive layer 12 may be, for example but not limited to, a polyolefin resin, a polyester resin, a polyether resin, an epoxy resin, or a combination thereof. The thickness of the first adhesive layer 12 is typically between 0.1 micrometers (μm) and 10 micrometers (μm), preferably between 3 micrometers (μm) and 8 micrometers (μm). In one embodiment of the present invention, the material of the first adhesive layer 12 is a polyolefin resin and the thickness of the first adhesive layer 12 is about 5 micrometers (μm).

The polyolefin sealing layer 13 can be attached to the aluminum foil layer 11 by the first adhesive layer 12. The polyolefin sealing layer 13 may be a single layer of a resin film or a multilayer resin film such as a polypropylene film, a polyethylene film, a modified polypropylene film or a cast polypropylene (CPP) film. The polyolefin sealing layer 13 has heat sealability and can be used to improve the chemical resistance of a highly corrosive electrolyte, provide sufficient heat seal strength, and prevent moisture intrusion to maintain the chemical properties of the electrolyte. In order to fully prevent the occurrence of pinholes and reduce The production cost of the polyolefin sealing layer 13 can be between 20 micrometers (μm) and 80 micrometers (μm) with less material usage and lower production costs. In one embodiment of the present invention, the heat sealing performance and processability are considered. The polyolefin sealing layer 13 may be, for example, a three-layer cast polypropylene (CPP) film and the thickness of the polyolefin sealing layer 13 is about 60 micrometers (μm). The structure of the cast polypropylene film is generally applied to the adhesive layer/intermediate layer/heat seal layer, and the film can be formed by a three-layer co-extrusion or co-blowing process. The adhesive layer may be a polypropylene polypropylene (polypropylene random copolymer, PP-R) film with enhanced adhesion and good punchability. The intermediate layer is used for strength support and may be a rigid Homo polypropylene (PP-H) film. The heat seal layer may be a polypropylene random copolymer (PP-R) film having good heat sealability and good punchability. However, embodiments of the adhesive layer, the intermediate layer, and the heat seal layer are not limited thereto.

The second adhesive layer 14 is disposed on the other surface of the aluminum foil layer 11 with respect to the first adhesive layer 12. The material of the second adhesive layer 14 may be, for example but not limited to, a polyolefin resin, a polyester resin, a polyether resin, an epoxy resin, or a combination thereof. The thickness of the second adhesive layer 14 is typically between 0.1 micrometers (μm) and 10 micrometers (μm), preferably between 5 micrometers (μm) and 8 micrometers (μm). In one embodiment of the present invention, the material of the second adhesive layer 14 is a polyester resin and the thickness of the second adhesive layer 14 is about 8 micrometers (μm).

The heat resistant resin layer 15 is attached to the aluminum foil layer 11 by the second adhesive layer 14, as shown in Fig. 1. The material constituting the heat resistant resin layer 15 is a heat resistant resin which does not melt at the heat sealing temperature at the time of heat sealing molding. The heat resistant resin layer 15 may be, for example, a polyamide film or a polyester film, which may be a single layer film or a multilayer film formed of a plurality of layers. Considering the sufficient strength of the packaging material and improving the formability, the heat resistant resin layer 15 The thickness can be between 9 micrometers (μm) and 50 micrometers (μm). In one embodiment of the present invention, the heat resistant resin layer 15 is a polyimide film and the heat resistant resin layer 15 has a thickness of about 25 micrometers (μm).

The heat sensing layer 16 is disposed on one surface of the heat resistant resin layer 15, as shown in Fig. 1. The material of the thermal sensing layer 16 is a substance whose color can change with temperature to indicate the change of temperature, so the thermal sensing layer 16 can express the change of temperature according to the change of the color according to the temperature. In one embodiment of the present creation, the thermal sensing layer 16 is irreversible in terms of temperature change indication. After the thermal sensing layer 16 reaches a certain temperature, for example, above a predetermined temperature, the thermal sensing layer 16 changes the indicator color, but after the color change, the changed indicator color recovery is not changed due to the temperature returning to the original state. To the original state. In addition, the thermal sensing layer 16 may have two or more indicative variables as needed, that is, the thermal sensing layer 16 may indicate two or more degrees of temperature change, wherein the indicating color is at two or more different temperatures. Under the change, the indication after the change is different from the indication before the change, so that the thermal shock state can be examined in more detail.

In one embodiment of the present invention, the heat sensing layer 16 is formed by coating an irreversible thermochromic ink on the heat resistant resin layer 15. The irreversible thermochromic ink is a temperature sensitive coating which is made from a compound whose color changes at a specific temperature, so that the thermochromic ink has a color tone which changes with temperature, thereby allowing the user to change the color of the ink by the thermochromic color. And identify the change in temperature. Thermochromic inks can be classified into reversible thermochromic inks and irreversible thermochromic inks. A reversible thermochromic ink that changes color due to heating and returns to its original color upon cooling. Irreversible thermochromic ink that changes color due to heating but does not return to its original color when cooled. In one embodiment of the present invention, the heat sensing layer 16 is formed by coating an irreversible thermochromic ink on the heat resistant resin layer 15, and a suitable coating method may be, but not limited to, coating. Coating or printing. The thickness of the thermal sensing layer 16 is between about 5 micrometers (μm) and 150 micrometers (μm), preferably between 20 micrometers (μm) and 40 micrometers (μm).

The thermal sensing layer 16 can accept two or more levels of indicative variables depending on the temperature to which the battery is subjected, or three or more indicative variables, if desired. In the electrical test results of general secondary batteries, when the battery is operated at a temperature higher than 60 ° C, the operating temperature is higher than the normal operating value, indicating that the battery life is short, and the battery will be short-circuited when the temperature is higher than 70 ° C. The risk should be scrapped. In one embodiment of the present invention, the thermal sensing layer 16 indicates three levels of temperature change, the thermal sensing layer 16 is shown as being transparent and colorless below 50 ° C, and the thermal sensing layer 16 is shown as pale pink above 55 ° C. Color, the thermal sensing layer 16 is shown in pink when it is above 65 °C. By the arrangement of the thermal sensing layer 16, the inspector can directly visually check whether the operating temperature of the battery is overheated, without additionally configuring the temperature sensor to measure the surface of the battery at a single point, and the battery can be displayed by the thermal sensing layer 16. The overall temperature range can also be used to accurately check the thermal shock condition of the battery as a whole, thereby improving the process. In addition, the material of the thermal sensing layer 16 can be adjusted according to different product inspection requirements to adjust the color change temperature of the thermal sensing layer 16, for example, depending on the maximum operating temperature of the battery, the tolerance of the critical temperature, or the temperature at which the battery is exploded and burned. A thermochromic ink with a corresponding color change temperature to meet thermal testing requirements. In addition, since the discoloration of the thermal sensing layer 16 is irreversible, the battery pack thus tested can provide higher reliability to downstream customers.

This creation has the following advantages:

1. The battery packaging film used in the battery electrical test can accurately monitor the overall temperature of the battery when the battery is discharged, and is not limited to the temperature of the temperature sensor, and the color change of the thermal sensing layer can be used. Operators save extra Mark the steps and reduce the risk of misplacement.

2. By changing the color to an irreversible thermal sensing layer, the reliability of downstream manufacturers or users for electrical test results can be improved.

3. Since the overheated position of the battery can be accurately marked, the process problem can be more clearly provided, so that the problem in the process can be effectively improved, thereby reducing the output of defective products.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any person skilled in the art can make various changes and refinements without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

10‧‧‧Battery packaging film

11‧‧‧Aluminum foil layer

12‧‧‧First adhesive layer

13‧‧‧Polyolefin sealant

14‧‧‧Second Adhesive Layer

15‧‧‧Heat resistant resin layer

16‧‧‧Thermal sensing layer

Claims (12)

A battery packaging film for battery electrical testing, comprising: an aluminum foil layer; a first adhesive layer disposed on a surface of the aluminum foil layer; a polyolefin sealing layer, by the first adhesive layer Attached to the aluminum foil layer; a second adhesive layer disposed on the other surface of the aluminum foil layer relative to the first adhesive layer; a heat resistant resin layer adhered to the aluminum foil layer by the second adhesive layer And a heat sensing layer disposed on a surface of the heat resistant resin layer. The battery packaging film of claim 1, wherein the heat sensing layer has a thickness of between 5 micrometers (μm) and 150 micrometers (μm). The battery packaging film of claim 1, wherein the thermal sensing layer is indicative of three degrees of temperature change. The battery packaging film according to claim 1, wherein the heat sensing layer is formed by coating an irreversible thermochromic ink on the heat resistant resin layer, and the color of the irreversible thermochromic ink changes according to temperature. And the changed color will not revert to the previous color. The battery packaging film of claim 4, wherein the thermochromic ink has a color tone that varies with temperature. The battery packaging film of claim 1, wherein the aluminum foil layer has a thickness of between 10 micrometers (μm) and 100 micrometers (μm). The battery packaging film of claim 1, wherein the first adhesive layer has a thickness of between 0.1 micrometers (μm) and 10 micrometers (μm). The battery packaging film of claim 1, wherein the second adhesive layer has a thickness of between 0.1 micrometers (μm) and 10 micrometers (μm). The battery packaging film of claim 1, wherein the polyolefin sealing layer is a cast polypropylene (CPP) film. The battery packaging film of claim 1, wherein the polyolefin sealing layer has a thickness of between 20 micrometers (μm) and 80 micrometers (μm). The battery packaging film according to claim 1, wherein the heat resistant resin layer is a polyamide film or a polyester film. The battery packaging film of claim 1, wherein the heat resistant resin layer has a thickness of between 9 micrometers (μm) and 50 micrometers (μm).