Welding leakage laser recognition method

Abstract

The application discloses a welding laser leakage identification method. The welding laser leakage identification method comprises the following steps: setting a detection film layer on a to-be-welded object, the detection film layer being prepared from a high-molecular polymer and a detection substance; performing laser welding on the to-be-welded object; and detecting the gas type around the laser welding position, when the detection gas generated by the detection substance is detected, it indicates that laser leakage occurs during laser welding. The welding laser leakage identification method adopts the detection film layer containing the detection substance, such as protein substance, nitrogen-containing derivative of hydrocarbon and sulfur-containing derivative of hydrocarbon, which is connected to the to-be-welded object, such as an electric core. In the laser welding, if laser leakage occurs, special smell will be generated. By detecting the gas smell around the laser welding position, if the burnt smell can be detected, it indicates that laser leakage occurs during laser welding, reminding the operator that the electric core has the laser leakage phenomenon and needs to be processed in time.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and in particular to a method for identifying welding leaks using laser technology. Background Technology

[0002] Global climate change has led to increasing attention to new energy sources, resulting in a robust development momentum in the new energy industry, particularly for lithium batteries. Demand for lithium batteries continues to rise, prompting related lithium battery companies to expand production. However, during the laser welding process of the top cover and aluminum casing in lithium battery production, laser leakage frequently occurs. This leakage leads to poor welding quality, further reducing product yield and increasing the number of defective products. Summary of the Invention

[0003] Therefore, in the traditional lithium battery production process, laser leakage often occurs during the laser welding process of the top cover and aluminum shell, leading to poor welding quality, reduced product yield, and an increase in defective products. It is necessary to provide a method for identifying laser leakage during welding. The laser leakage identification method of this invention can accurately and quickly identify whether laser leakage occurs during the laser welding process in lithium battery production.

[0004] One embodiment of this application provides a method for identifying welding leak lasers.

[0005] A method for identifying weld leak lasers includes the following steps:

[0006] A detection film layer is applied to the object to be welded, the detection film layer being prepared from a polymer and a detection substance;

[0007] Laser welding is performed on the object to be welded;

[0008] The type of gas around the laser welding position is detected. When a detection gas generated by the detection substance is detected, it indicates that there is a laser leak during laser welding.

[0009] In some embodiments, the detection substance includes one or more of the following: proteinaceous substances, nitrogen-containing derivatives of hydrocarbons, and sulfur-containing derivatives of hydrocarbons.

[0010] In some embodiments, the protein-like substance includes one or both of plant proteins and animal proteins.

[0011] In some embodiments, the nitrogen-containing derivative of the hydrocarbon is one or more of amines, imines, hydrazines, hydrazones, nitriles, and amides;

[0012] And / or, the sulfur-containing derivative of the hydrocarbon is one or more of thiols, thioethers, thiocarboxylic acids, thiocarboxylic acid esters, sulfonic acids, and sulfonates.

[0013] In some embodiments, the polymer comprises one or more of polyethylene terephthalate, polyethylene, and polypropylene.

[0014] In some embodiments, the mass percentage of the detection substance in the detection membrane is not less than 8%.

[0015] In some embodiments, the detection membrane layer further includes an additive, which includes one or more of titanium dioxide and dodecyl alcohol ester, and the mass percentage of the additive in the detection membrane layer is not greater than 1%.

[0016] In some embodiments, the method for preparing the detection film includes the following steps:

[0017] The detection substance, polymer, and additives are melt-mixed to form a molten mixture;

[0018] The molten mixture is extruded and then stretched and slit to prepare the detection film layer containing the detection substance on both sides.

[0019] In some embodiments, the method for preparing the detection film includes the following steps:

[0020] The detection substance, polymer, and additives are melt-mixed to form a molten mixture;

[0021] The molten mixture is extruded and then stretched and slit to prepare a film. The film is then thermally bonded to a PET film to form a detection film layer containing the detection substance on one side.

[0022] In some embodiments, the method for preparing the detection film includes the following steps:

[0023] The detection substance, polymer, and additives are melt-mixed to form a molten mixture;

[0024] The molten mixture is coated onto at least one surface of a PET film using a scraper to form a single or double layer of the detection film containing the detection substance.

[0025] The aforementioned laser leakage identification method involves attaching a detection film containing detection substances such as proteins, nitrogen-containing derivatives of hydrocarbons, or sulfur-containing derivatives of hydrocarbons to the object to be welded, such as a battery cell. During laser welding, if laser leakage occurs, a special odor, such as a burnt smell, will be produced. By detecting the types of gases around the laser welding location, such as nitric oxide, nitrogen dioxide, and hydrogen sulfide, it is indicated that laser leakage has occurred during laser welding, reminding the operator that the battery cell has laser leakage and needs to be dealt with promptly. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings. In the following description, the same reference numerals denote the same parts.

[0028] Figure 1 This is a schematic diagram of the detection equipment in the welding leak laser identification method according to an embodiment of the present invention. Detailed Implementation

[0029] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0030] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0031] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0033] In the description of this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0035] This application provides a method for identifying laser leakage during welding, addressing the common problem of laser leakage in the laser welding process of the top cover and aluminum shell during existing lithium battery production. Laser leakage leads to poor welding quality, further reducing product yield and increasing the number of defective products. The method for identifying laser leakage during welding will be described below with reference to embodiments and accompanying drawings.

[0036] The laser leakage identification method for welding described in this application can be used to detect and identify whether laser leakage occurs during laser welding of an object to be welded. Specifically, the above-mentioned laser leakage identification method for welding can be used in the field of lithium batteries, for example, to detect whether laser leakage occurs during the laser welding process of the top cover and aluminum shell in the cell manufacturing process of lithium batteries.

[0037] For example, one embodiment of this application provides a method for identifying welding leak lasers.

[0038] A method for identifying weld leak lasers includes the following steps:

[0039] Step 1: Apply a detection film layer to the object to be welded. The detection film layer is prepared from a polymer and a detection substance.

[0040] Step 2: Perform laser welding on the object to be welded.

[0041] Step 3: Detect the type of gas around the laser welding position. When a detection gas generated by the detection substance is detected, it indicates that there is a laser leak during laser welding.

[0042] In some embodiments, the detection substance includes one or more of the following: proteinaceous substances, nitrogen-containing derivatives of hydrocarbons, and sulfur-containing derivatives of hydrocarbons.

[0043] In some embodiments, the protein-like substance includes one or both of plant proteins and animal proteins.

[0044] In some embodiments, plant proteins include soy protein; animal proteins include keratin, collagen, etc.

[0045] In some embodiments, the nitrogen-containing derivative of the hydrocarbon includes one or more of amines, imines, hydrazines, hydrazones, nitriles, and amides. The nitrogen-containing derivative of the hydrocarbon contains at least 16 carbon atoms.

[0046] In some embodiments, the sulfur-containing derivative of the hydrocarbon includes one or more of thiols, thioethers, thiocarboxylic acids, thiocarboxylic esters, sulfonic acids, and sulfonates. The sulfur-containing derivative of the hydrocarbon contains at least 16 carbon atoms.

[0047] In some embodiments, the polymer comprises one or more of polyethylene terephthalate (PET), polyethylene (PE), and polypropylene (PP).

[0048] In some embodiments, the mass percentage of the detection substance in the detection membrane is not less than 8%.

[0049] In some embodiments, the detection membrane layer further includes an additive, which includes one or more of titanium dioxide and dodecyl alcohol ester, and the mass percentage of the additive in the detection membrane layer is not greater than 1%.

[0050] In some embodiments, the method for preparing the detection film includes the following steps:

[0051] 8%wt of the detection substance, 91%wt of the polymer (such as polyethylene terephthalate PET, polyethylene PE or polypropylene PP) and 1%wt of the additives are melt-mixed to form a melt mixture;

[0052] The molten mixture is extruded and then stretched and slit to prepare the detection film layer containing the detection substance on both sides.

[0053] In some embodiments, the method for preparing the detection film includes the following steps:

[0054] 8%wt of the detection substance, 91%wt of the polymer (such as polyethylene terephthalate PET, polyethylene PE or polypropylene PP) and 1%wt of the additives are melt-mixed to form a melt mixture;

[0055] The molten mixture is extruded and then stretched and slit to prepare a film. The film is then thermally bonded to a PET film to form a detection film layer containing the detection substance on one side.

[0056] In some embodiments, the method for preparing the detection film includes the following steps:

[0057] 8%wt of the detection substance, 91%wt of the polymer (e.g., polyethylene terephthalate PET, polyethylene PE, or polypropylene PP) and 1%wt of the additives are melt-mixed to form a molten mixture; the molten mixture is coated onto at least one surface of a PET film using a scraper to form a single or double layer of the detection film containing the detection substance.

[0058] In some embodiments, detecting the gas odor around the laser welding position includes the following steps: using a detection device to detect the type of gas around the laser welding position in real time.

[0059] In some of these embodiments, see Figure 1 As shown, Figure 1 This is a schematic diagram of the detection equipment in the welding leak laser identification method according to an embodiment of this application. The detection equipment is an SK / MIC-800 industrial pump sampling portable composite gas dust detector alarm online monitoring system, specifically with NO... X The alarm for nitrogen oxide detectors and SO2 sulfur dioxide detectors are manufactured by Shenzhen Dongri Yingneng Technology Co., Ltd.

[0060] In some embodiments, the welding leak laser identification method further includes the following steps:

[0061] An alarm is triggered by an alarm component when the type of gas around the laser welding location is detected.

[0062] In some embodiments, the alarm component may be one or more of a flashing light, a buzzer, and a vibrator. The alarm component can alert operators to take timely action through visual, auditory, and tactile cues.

[0063] Example 1

[0064] This embodiment provides a method for identifying laser leakage during welding. This method is used to detect whether laser leakage occurs during the laser welding process of the top cover and aluminum casing of a lithium battery cell.

[0065] A method for identifying weld leak lasers includes the following steps:

[0066] Step 1: Prepare the detection film. The preparation method for the detection film includes the following steps:

[0067] 8% wt of soybean protein, 91% wt of polyethylene terephthalate (PET) and 1% wt of titanium dioxide are melt-mixed to form a molten mixture; the molten mixture is extruded and then stretched and slit to prepare the detection film layer containing the detection substance on both sides.

[0068] Step 2: Wrap the above-mentioned detection film layer on the bare battery cell.

[0069] Step 3: Laser welding is performed on the top cover and aluminum shell of the bare battery cell.

[0070] Step 4: Use detection equipment to detect the type of gas around the laser welding position between the top cover and the aluminum shell of the bare battery cell. When a burning smell is produced, combined with the gas detected by the detection equipment, it indicates that there is a laser leak during laser welding, and the alarm component will sound an alarm.

[0071] The laser leakage identification method in this embodiment is used to detect whether there is laser leakage in the laser welding process of the top cover and aluminum shell of the battery cell in the lithium battery field. After the manufacturing yield of the battery cell is 100% and the inspection yield is 100%.

[0072] Example 2

[0073] This embodiment provides a method for identifying laser leakage during welding. This method is used to detect whether laser leakage occurs during the laser welding process of the top cover and aluminum casing of a lithium battery cell.

[0074] A method for identifying weld leak lasers includes the following steps:

[0075] Step 1: Prepare the detection film. The preparation method for the detection film includes the following steps:

[0076] 8%wt of collagen, 91%wt of polyethylene terephthalate (PET) and 1%wt of titanium dioxide are melt-mixed to form a molten mixture; the molten mixture is extruded and then stretched and slit to prepare a film; the film is then microthermally bonded to a PET film to form a detection film layer containing the detection substance on one side.

[0077] Step 2: Wrap the above-mentioned detection film layer on the bare battery cell.

[0078] Step 3: Laser welding is performed on the top cover and aluminum shell of the bare battery cell.

[0079] Step 4: Use detection equipment to detect the type of gas around the laser welding position between the top cover and the aluminum shell of the bare battery cell. When a burning smell is produced, combined with the gas detected by the detection equipment, it indicates that there is a laser leak during laser welding, and the alarm component will sound an alarm.

[0080] The laser leakage identification method in this embodiment is used to detect whether there is laser leakage in the laser welding process of the top cover and aluminum shell of the battery cell in the lithium battery field. After the battery cell manufacturing yield is 100% and the inspection yield is 99%.

[0081] Example 3

[0082] This embodiment provides a method for identifying laser leakage during welding. This method is used to detect whether laser leakage occurs during the laser welding process of the top cover and aluminum casing of a lithium battery cell.

[0083] A method for identifying weld leak lasers includes the following steps:

[0084] Step 1: Prepare the detection film. The preparation method for the detection film includes the following steps:

[0085] 8%wt of collagen, 91%wt of polyethylene terephthalate and 1%wt of titanium dioxide are melt-mixed to form a molten mixture; the molten mixture is coated onto one surface of a PET film by a scraper to form a single-layer detection film containing the detection substance.

[0086] Step 2: Wrap the above-mentioned detection film layer on the bare battery cell.

[0087] Step 3: Laser welding is performed on the top cover and aluminum shell of the bare battery cell.

[0088] Step 4: Use detection equipment to detect the type of gas around the laser welding position between the top cover and the aluminum shell of the bare battery cell. When a burning smell is produced, combined with the gas detected by the detection equipment, it indicates that there is a laser leak during laser welding, and the alarm component will sound an alarm.

[0089] The laser leakage identification method in this embodiment is used to detect whether there is laser leakage in the laser welding process of the top cover and aluminum shell of the battery cell in the lithium battery field. After the battery cell manufacturing yield is 99% and the inspection yield is 98%, the manufacturing quality rate is 99%.

[0090] Example 4

[0091] This embodiment provides a method for identifying laser leakage during welding. This method is used to detect whether laser leakage occurs during the laser welding process of the top cover and aluminum casing of a lithium battery cell.

[0092] A method for identifying weld leak lasers includes the following steps:

[0093] Step 1: Prepare the detection film. The preparation method for the detection film includes the following steps:

[0094] 8%wt of keratin, 91%wt of polyethylene (PE) and 1%wt of titanium dioxide are melt-mixed to form a molten mixture; the molten mixture is coated onto both surfaces of a PET film using a scraper to form a double-layer detection film containing the detection substance.

[0095] Step 2: Wrap the above-mentioned detection film layer on the bare battery cell.

[0096] Step 3: Laser welding is performed on the top cover and aluminum shell of the bare battery cell.

[0097] Step 4: Use detection equipment to detect the type of gas around the laser welding position between the top cover and the aluminum shell of the bare battery cell. When a burning smell is produced, combined with the gas detected by the detection equipment, it indicates that there is a laser leak during laser welding, and the alarm component will sound an alarm.

[0098] The laser leakage identification method in this embodiment is used to detect whether there is laser leakage in the laser welding process of the top cover and aluminum shell of the battery cell in the lithium battery field. After the battery cell manufacturing yield is 99% and the inspection yield is 98.5%.

[0099] Example 5

[0100] This embodiment provides a method for identifying laser leakage during welding. This method is used to detect whether laser leakage occurs during the laser welding process of the top cover and aluminum casing of a lithium battery cell.

[0101] A method for identifying weld leak lasers includes the following steps:

[0102] Step 1: Prepare the detection film. The preparation method for the detection film includes the following steps:

[0103] 8% wt of sulfonic acid, 91% wt of polypropylene (PP) and 1% wt of dodecyl alcohol ester are melt-mixed to form a molten mixture; the molten mixture is coated onto both surfaces of a PET film by a scraper to form a double-layer detection film containing the detection substance.

[0104] Step 2: Wrap the above-mentioned detection film layer on the bare battery cell.

[0105] Step 3: Laser welding is performed on the top cover and aluminum shell of the bare battery cell.

[0106] Step 4: Use detection equipment to detect the type of gas around the laser welding position between the top cover and the aluminum shell of the bare battery cell. When a burning smell is produced, combined with the gas detected by the detection equipment, it indicates that there is a laser leak during laser welding, and the alarm component will sound an alarm.

[0107] The laser leakage identification method in this embodiment is used to detect whether there is laser leakage in the laser welding process of the top cover and aluminum shell of the battery cell in the lithium battery field. After the manufacturing yield of the battery cell is 100% and the inspection yield is 98%.

[0108] The aforementioned laser leakage identification method involves attaching a detection film containing detection substances such as proteins, nitrogen-containing derivatives of hydrocarbons, or sulfur-containing derivatives of hydrocarbons to the object to be welded, such as a battery cell. During laser welding, if laser leakage occurs, a special odor, such as a burnt smell, will be produced. By detecting the types of gases around the laser welding location, such as nitric oxide, nitrogen dioxide, and hydrogen sulfide, it is indicated that laser leakage has occurred during laser welding, reminding the operator that the battery cell has laser leakage and needs to be dealt with promptly.

[0109] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0110] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0111] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method for identifying welding leaks using laser technology, characterized in that, Includes the following steps: A detection film layer is applied to the object to be welded, the detection film layer being prepared from a polymer and a detection substance; Laser welding is performed on the object to be welded; The type of gas around the laser welding position is detected. When a detection gas generated by the detection substance is detected, it indicates that there is a laser leak during laser welding.

2. The welding leak laser identification method according to claim 1, characterized in that, The substances to be detected include one or more of the following: proteins, nitrogen-containing derivatives of hydrocarbons, and sulfur-containing derivatives of hydrocarbons.

3. The welding leak laser identification method according to claim 2, characterized in that, The protein-like substances include one or both of plant proteins and animal proteins.

4. The welding leak laser identification method according to claim 2, characterized in that, The nitrogen-containing derivative of the hydrocarbon is one or more of the following: amine, imine, hydrazine, hydrazone, nitrile, and amide. And / or, the sulfur-containing derivative of the hydrocarbon is one or more of thiols, thioethers, thiocarboxylic acids, thiocarboxylic acid esters, sulfonic acids, and sulfonates.

5. The welding leak laser identification method according to claim 2, characterized in that, The polymer includes one or more of polyethylene terephthalate, polyethylene, and polypropylene.

6. The welding leak laser identification method according to any one of claims 1 to 5, characterized in that, The mass percentage of the detection substance in the detection membrane layer is not less than 8%.

7. The welding leak laser identification method according to any one of claims 1 to 5, characterized in that, The detection membrane also includes additives, which include one or more of titanium dioxide and dodecyl alcohol ester, and the mass percentage of the additives in the detection membrane is not greater than 1%.

8. The welding leak laser identification method according to any one of claims 1 to 5, characterized in that, The method for preparing the detection membrane includes the following steps: The detection substance, polymer, and additives are melt-mixed to form a molten mixture; The molten mixture is extruded and then stretched and slit to prepare the detection film layer containing the detection substance on both sides.

9. The welding leak laser identification method according to any one of claims 1 to 5, characterized in that, The method for preparing the detection membrane includes the following steps: The detection substance, polymer, and additives are melt-mixed to form a molten mixture; The molten mixture is extruded and then stretched and slit to prepare a film. The film is then thermally bonded to a PET film to form a detection film layer containing the detection substance on one side.

10. The welding leak laser identification method according to any one of claims 1 to 5, characterized in that, The method for preparing the detection membrane includes the following steps: The detection substance, polymer, and additives are melt-mixed to form a molten mixture; The molten mixture is coated onto at least one surface of a PET film using a scraper to form a single or double layer of the detection film containing the detection substance.

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