Method of determining welding parameters and computer readable medium

Abstract

The application provides a welding parameter determination method and a computer readable medium. The welding parameter determination method comprises taking multiple values for each welding parameter, and performing ultrasonic welding on a battery electrode by using combinations of welding parameters with different values; obtaining welding power when each battery electrode is ultrasonically welded; and determining a range of a target welding parameter combination that meets a preset power requirement based on the welding power corresponding to each welding parameter combination and the preset power requirement. The welding parameter determination method for a battery electrode provided by the application performs ultrasonic welding on a battery electrode by using combinations of welding parameters with different values based on an orthogonal experiment method, and determines a range of a welding parameter combination that meets a suitable preset power requirement according to the welding parameter combination, so that the welding power of the battery electrode can be ensured to be within a reasonable range in subsequent welding processes, virtual welding and overwelding of the battery electrode are avoided, and the quality of a battery cell product is ensured.

Description

Technical Field

[0001] This invention relates to the field of battery manufacturing, and more specifically, to a method for determining welding parameters and a computer-readable medium. Background Technology

[0002] Lithium-ion batteries are a type of rechargeable battery that primarily relies on lithium ions (Li₂O₃). + Lithium ions move between the positive and negative electrodes to operate. During charging and discharging, lithium ions repeatedly insert and extract between the two electrodes. Due to their advantages such as high voltage, high specific energy, stable discharge voltage, good cycle performance, excellent safety performance, and long storage and operating life, lithium-ion batteries are widely used in electric vehicles, energy storage, and 3C (computer, communication, and consumer electronics) fields.

[0003] Lithium-ion batteries are assembled in various forms, including prismatic winding, prismatic cylindrical, stacked, and pouch cells. Among these processes, ultrasonic welding is widely used in lithium battery manufacturing due to its outstanding advantages in safety and environmental friendliness. In the welding of connecting tabs, the tabs need to be joined together, and ultrasonic welding is typically used. The strength of this weld directly determines the critical quality of the battery cell.

[0004] Therefore, how to improve the ultrasonic welding strength of lithium-ion battery electrodes (tabs) to ensure cell quality has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] The present invention aims to provide a method for determining welding parameters and a computer-readable medium. The method for determining welding parameters can improve the ultrasonic welding strength of lithium-ion battery electrodes and ensure the quality of the battery cells.

[0006] To achieve the above objectives, as one aspect of the present invention, a method for determining welding parameters of a battery electrode is provided, wherein the welding parameters include at least two of energy parameters, amplitude parameters, and pressure parameters, and the method for determining the welding parameters includes:

[0007] Multiple values ​​are taken for each of the welding parameters, and the battery electrodes are ultrasonically welded using combinations of welding parameters with different values.

[0008] Obtain the welding power when performing ultrasonic welding on each of the battery electrodes;

[0009] Based on the welding power corresponding to each combination of welding parameters and the preset power requirement, the range of target welding parameter combinations that meet the preset power requirement is determined.

[0010] As an optional embodiment of the present invention, the welding parameters include energy parameters, amplitude parameters, and pressure parameters.

[0011] As an optional embodiment of the present invention, the step of taking multiple values ​​for each of the welding parameters and performing ultrasonic welding on the battery electrodes using combinations of different values ​​of the welding parameters includes:

[0012] For each of the welding parameters, two values ​​are taken: a high level value and a low level value. Ultrasonic welding is performed using all combinations of high and low level values ​​for the energy parameter, the amplitude parameter, and the pressure parameter, respectively.

[0013] As an optional embodiment of the present invention, the step of taking multiple values ​​for each of the welding parameters and performing ultrasonic welding on the battery electrodes using combinations of welding parameters with different values ​​further includes:

[0014] For each welding parameter, the average of the corresponding high-level value and the corresponding low-level value is taken, and multiple battery electrodes are ultrasonically welded by a combination of the corresponding average values ​​of the energy parameter, the amplitude parameter and the pressure parameter.

[0015] As an optional embodiment of the present invention, the two battery electrodes are ultrasonically welded using a combination of the energy parameter, the amplitude parameter, and the pressure parameter all being the corresponding average values.

[0016] As an optional embodiment of the present invention, the preset power requirement is:

[0017] When multiple welding parameters are all within the range of the obtained target welding parameter combination, the welding power when ultrasonically welding the battery electrode with this welding parameter combination is within the preset power range.

[0018] As an optional embodiment of the present invention, determining the range of target welding parameter combinations that satisfy the preset power requirement based on the welding power corresponding to each combination of welding parameters and the preset power requirement includes:

[0019] Based on the welding power corresponding to each combination of welding parameters, determine the significance factor among the welding parameters that corresponds to the welding power;

[0020] Based on the determined significance factor, the range of target welding parameter combinations that meet the preset power requirements is determined.

[0021] As an optional embodiment of the present invention, the battery electrode includes a positive electrode and a negative electrode, and the method for determining the welding parameters includes determining the range of target welding parameter combinations corresponding to the positive electrode and the range of target welding parameter combinations corresponding to the negative electrode, respectively.

[0022] As an optional embodiment of the present invention, the energy parameter of the positive electrode corresponds to a low level value of 100J and a high level value of 240J; the amplitude parameter of the positive electrode corresponds to a low level value of 30μm and a high level value of 60μm; the pressure parameter of the positive electrode corresponds to a low level value of 15Psi and a high level value of 35Psi.

[0023] The energy parameters of the negative electrode have a low level value of 230J and a high level value of 370J; the amplitude parameters of the negative electrode have a low level value of 50μm and a high level value of 70μm; the pressure parameters of the negative electrode have a low level value of 20Psi and a high level value of 40Psi.

[0024] As an optional embodiment of the present invention, the preset power range corresponding to the positive electrode is greater than 900W and less than 1400W; the preset power range corresponding to the negative electrode is greater than 2900W and less than 4000W.

[0025] As an optional embodiment of the present invention, obtaining the welding power during ultrasonic welding of each of the battery electrodes includes:

[0026] The welding power is obtained by acquiring the electrical power of the welding machine when ultrasonic welding is performed on each of the battery electrodes.

[0027] As a second aspect of the present invention, a computer-readable medium is provided, on which a computer program is stored, which, when executed by a processor, implements the method for determining welding parameters described above.

[0028] In the method for determining welding parameters and the computer-readable medium provided by this invention, the method for determining welding parameters is based on the DOE orthogonal experimental method and uses combinations of welding parameters with different values ​​to perform ultrasonic welding on battery electrodes. The influence of changes in welding parameters on the ultrasonic welding effect can be determined with fewer experiments, and the range of welding parameter combinations that meet the requirements can be determined according to the appropriate preset power requirements. In this way, the welding power of battery electrodes can be kept within a reasonable range in subsequent welding processes, avoiding poor welding and over-welding of battery electrodes, and ensuring the quality of battery cell products. Attached Figure Description

[0029] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0030] Figure 1 This is a flowchart illustrating the method for determining welding parameters provided in an embodiment of the present invention. Detailed Implementation

[0031] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0032] Ultrasonic welding is a critical process in lithium battery manufacturing, directly impacting cell quality and yield. Common ultrasonic welding failures include incomplete welds and over-welding, which can lead to electrode detachment at the welded position during subsequent assembly, resulting in excessive internal resistance or even open circuits within the cell. Therefore, strict control of ultrasonic welding parameters is essential to prevent incomplete welds or over-welding.

[0033] To address the aforementioned technical problems, as one aspect of the present invention, a method for determining welding parameters of a battery electrode is provided. The welding parameters include at least two of the following: energy parameters (i.e., the energy of the sound wave during ultrasonic welding), amplitude parameters (i.e., the amplitude of the sound wave during ultrasonic welding), and pressure parameters (i.e., the pressure applied to the welding surface during ultrasonic welding). Figure 1 As shown, the welding parameters are indeed...

[0034] The determination methods include:

[0035] Step S1: Take multiple values ​​for each welding parameter, and perform ultrasonic welding on the battery electrode using combinations of welding parameters with different values.

[0036] Step S2: Obtain the welding power when performing ultrasonic welding on each battery electrode;

[0037] Step S3: Based on the welding power corresponding to each combination of welding parameters and the preset power requirements, determine the range of target welding parameter combinations that meet the preset power requirements.

[0038] Compared to the tensile properties and other characteristics of the electrodes after welding, the welding power during battery electrode welding provides a more intuitive and convenient way to demonstrate the welding effect. The method for determining the welding parameters of battery electrodes provided by this invention is based on the DOE orthogonal experimental method. It uses combinations of welding parameters with different values ​​to perform ultrasonic welding on the battery electrodes. With fewer experiments, the impact of changes in welding parameters on the ultrasonic welding effect can be determined. Furthermore, based on suitable preset power requirements, the range of welding parameter combinations that meet these requirements can be determined. This ensures that the welding power of the battery electrodes remains within a reasonable range in subsequent welding processes, avoiding incomplete or over-welded connections and guaranteeing the quality of the battery cell products.

[0039] As an optional embodiment of the present invention, the welding parameters include energy parameters, amplitude parameters, and pressure parameters.

[0040] As an optional embodiment of the present invention, taking multiple values ​​for each welding parameter and performing ultrasonic welding on the battery electrode using combinations of welding parameters with different values ​​includes:

[0041] For each welding parameter, two values ​​are taken: a high level value and a low level value. Ultrasonic welding is performed using all combinations of high and low level values ​​for energy parameters, amplitude parameters, and pressure parameters, respectively.

[0042] In this embodiment of the invention, the orthogonal experiment is a three-factor, two-level orthogonal experiment, that is, it involves three factors: energy parameter, amplitude parameter and pressure parameter. Each factor has two levels: a high level value and a low level value, resulting in a total of 8 combinations. Correspondingly, 8 ultrasonic welding operations are performed. The effect of each factor on the welding power can be determined by the orthogonal experiment algorithm based on the change of the response variable welding power.

[0043] As an optional embodiment of the present invention, based on the welding power corresponding to each combination of welding parameters and the preset power requirement, the range of target welding parameter combinations that meet the preset power requirement is determined, including:

[0044] Based on the welding power corresponding to each combination of welding parameters, determine the significant factors in the welding parameters that correspond to the welding power.

[0045] Based on the identified significance factors, determine the range of target welding parameter combinations that meet the preset power requirements.

[0046] For example, when welding parameters include energy parameters, amplitude parameters, and pressure parameters, the factors affecting the response variable welding power include first-order factors: energy parameters, amplitude parameters, and pressure parameters, as well as second-order interaction factors: energy parameters × amplitude parameters, energy parameters × pressure parameters, and amplitude parameters × pressure parameters.

[0047] In some embodiments of the present invention, the significant factors affecting welding power are determined experimentally to include: energy parameter, amplitude parameter, and energy parameter × amplitude parameter.

[0048] To verify the significance of the significance factor on welding power, as a preferred embodiment of the present invention, the method further includes a step of conducting multiple sets of center value experiments, specifically:

[0049] Taking multiple values ​​for each welding parameter and performing ultrasonic welding on the battery electrodes using combinations of different welding parameter values ​​also includes:

[0050] For each welding parameter, the average of the corresponding high-level value and the corresponding low-level value is taken, and multiple battery electrodes are ultrasonically welded by a combination of taking the corresponding average values ​​of energy parameter, amplitude parameter and pressure parameter.

[0051] As an optional embodiment of the present invention, two sets of center value experiments can be performed, namely, ultrasonic welding of two battery electrodes with the energy parameter, amplitude parameter and pressure parameter all taking the corresponding average values.

[0052] In this embodiment of the invention, a total of 8 ultrasonic welding experiments were conducted under all combinations of high and low levels of energy parameters, amplitude parameters, and pressure parameters, plus 2 center value experiments, for a total of 10 experiments.

[0053] As an optional embodiment of the present invention, the preset power requirement is:

[0054] When multiple welding parameters are all within the range of the obtained target welding parameter combination, the welding power when ultrasonically welding the battery electrode with this welding parameter combination is within the preset power range.

[0055] As an optional embodiment of the present invention, the battery electrode includes a positive electrode and a negative electrode, and the method for determining the welding parameters includes determining the range of the target welding parameter combination corresponding to the positive electrode and the range of the target welding parameter combination corresponding to the negative electrode, respectively.

[0056] As an optional embodiment of the present invention, the energy parameter of the positive electrode corresponds to a low level value of 100J and a high level value of 240J; the amplitude parameter of the positive electrode corresponds to a low level value of 30μm and a high level value of 60μm; the pressure parameter of the positive electrode corresponds to a low level value of 15Psi and a high level value of 35Psi.

[0057] The energy parameters of the negative electrode correspond to a low level value of 230J and a high level value of 370J; the amplitude parameters of the negative electrode correspond to a low level value of 50μm and a high level value of 70μm; the pressure parameters of the negative electrode correspond to a low level value of 20Psi and a high level value of 40Psi.

[0058] As an optional embodiment of the present invention, the preset power range corresponding to the positive electrode is greater than 900W and less than 1400W; the preset power range corresponding to the negative electrode is greater than 2900W and less than 4000W.

[0059] As an optional embodiment of the present invention, obtaining the welding power during ultrasonic welding of each battery electrode includes:

[0060] The power consumption of the welding machine during ultrasonic welding of each battery electrode is obtained to determine the welding power.

[0061] To facilitate understanding by those skilled in the art, the following provides a detailed process for determining the welding parameters for the positive and negative electrodes using the welding parameter determination method provided in the embodiments of the present invention:

[0062] Example 1:

[0063] The positive electrode welding parameters include energy parameters, amplitude parameters, and pressure parameters. The low-level value of the energy parameter is 100J, and the high-level value is 240J; the low-level value of the amplitude parameter is 30μm, and the high-level value is 60μm; the low-level value of the pressure parameter is 15Psi, and the high-level value is 35Psi.

[0064] A three-factor, two-level orthogonal experiment was conducted, with 8 sets of ultrasonic welding experiments and 2 sets of center value experiments, taking all combinations of high and low level values ​​for energy parameters, amplitude parameters, and pressure parameters respectively.

[0065] The significant factors affecting the positive electrode welding power were determined by algorithm analysis of experimental data, including: energy parameter, amplitude parameter, and energy parameter × amplitude parameter.

[0066] Further calculations show that the parameter combination range that satisfies the preset power range of greater than 900W and less than 1400W is: energy parameter 120J~220J, amplitude parameter 40μm~50μm, and pressure parameter 15Psi~25Psi.

[0067] When performing positive electrode ultrasonic welding, a parameter combination that falls within the above parameter combination range can be selected. For example, an energy parameter of 170J, an amplitude parameter of 45μm, and a pressure parameter of 22Psi can be selected.

[0068] Example 2:

[0069] The negative electrode welding parameters include energy parameters, amplitude parameters, and pressure parameters. The low-level value of the energy parameter is 230J, and the high-level value is 370J; the low-level value of the amplitude parameter is 50μm, and the high-level value is 70μm; the low-level value of the pressure parameter is 20Psi, and the high-level value is 40Psi.

[0070] A three-factor, two-level orthogonal experiment was conducted, with 8 sets of ultrasonic welding experiments and 2 sets of center value experiments, taking all combinations of high and low level values ​​for energy parameters, amplitude parameters, and pressure parameters respectively.

[0071] The significant factors affecting the welding power of the negative electrode were determined by algorithm analysis of experimental data, including: energy parameter, amplitude parameter, and energy parameter × amplitude parameter.

[0072] Further calculations show that the parameter combination range that satisfies the preset power range of greater than 2900W and less than 4000W is: energy parameter 230J~330J, amplitude parameter 48μm~58μm, and pressure parameter 25Psi~35Psi.

[0073] When performing ultrasonic welding of the negative electrode, a parameter combination that falls within the above parameter combination range can be selected. For example, an energy parameter of 320J, an amplitude parameter of 56μm, and a pressure parameter of 31Psi can be selected.

[0074] As a second aspect of the present invention, a computer-readable medium is provided, on which a computer program is stored, which, when executed by a processor, implements the method for determining welding parameters provided in the embodiments of the present invention.

[0075] Compared to the tensile properties and other properties of the electrodes after welding, the welding power during battery electrode welding can more intuitively and conveniently reflect the welding effect of the battery electrodes. The computer program stored in the computer-readable medium provided by this invention uses a combination of welding parameters with different values ​​to perform ultrasonic welding on battery electrodes based on the DOE orthogonal experimental method. With fewer experiments, the impact of changes in welding parameters on the ultrasonic welding effect can be determined, and the range of welding parameter combinations that meet the appropriate preset power requirements can be determined. This ensures that the welding power of the battery electrodes is within a reasonable range in subsequent welding processes, avoiding incomplete or over-welded connections and guaranteeing the quality of the battery cell product.

[0076] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for determining welding parameters for battery electrodes, characterized in that, The welding parameters include energy parameters, amplitude parameters, and pressure parameters, and the methods for determining the welding parameters include: Multiple values ​​are taken for each of the welding parameters, and the battery electrodes are ultrasonically welded using combinations of welding parameters with different values. The power consumption of the welding machine during ultrasonic welding of each of the battery electrodes is obtained to obtain the welding power; Based on the welding power corresponding to each combination of welding parameters, a significant factor corresponding to the welding power is determined among the welding parameters; according to the determined significant factor, the range of target welding parameter combinations that meet the preset power requirement is determined; wherein, the preset power requirement is: when multiple welding parameters are all within the range of the obtained target welding parameter combinations, the welding power when ultrasonically welding the battery electrode with the welding parameter combination is within the preset power range.

2. The method for determining welding parameters according to claim 1, characterized in that, The step of taking multiple values ​​for each of the welding parameters and performing ultrasonic welding on the battery electrodes using combinations of different values ​​of the welding parameters includes: For each of the welding parameters, two values ​​are taken: a high level value and a low level value. Ultrasonic welding is performed using all combinations of high and low level values ​​for the energy parameter, the amplitude parameter, and the pressure parameter, respectively.

3. The method for determining welding parameters according to claim 2, characterized in that, The step of taking multiple values ​​for each of the welding parameters and performing ultrasonic welding on the battery electrodes using combinations of different values ​​of the welding parameters further includes: For each welding parameter, the average of the corresponding high-level value and the corresponding low-level value is taken, and multiple battery electrodes are ultrasonically welded by a combination of the corresponding average values ​​of the energy parameter, the amplitude parameter and the pressure parameter.

4. The method for determining welding parameters according to claim 2 or 3, characterized in that, The battery electrodes include a positive electrode and a negative electrode, and the method for determining the welding parameters includes determining the range of target welding parameter combinations corresponding to the positive electrode and the range of target welding parameter combinations corresponding to the negative electrode, respectively.

5. The method for determining welding parameters according to claim 4, characterized in that, The energy parameters of the positive electrode correspond to a low level value of 100J and a high level value of 240J; the amplitude parameters of the positive electrode correspond to a low level value of 30μm and a high level value of 60μm; the pressure parameters of the positive electrode correspond to a low level value of 15Psi and a high level value of 35Psi. The energy parameters of the negative electrode have a low level value of 230J and a high level value of 370J; the amplitude parameters of the negative electrode have a low level value of 50μm and a high level value of 70μm; the pressure parameters of the negative electrode have a low level value of 20Psi and a high level value of 40Psi.

6. A computer-readable medium storing a computer program that, when executed by a processor, implements the method for determining welding parameters according to any one of claims 1 to 5.

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