Battery tab packaging method and system
By calculating the welding positions of the inner and outer tabs and the depth of tape wrapping, the problem of inconsistent melting of the inner and outer tabs in lithium-ion batteries under high capacity and high power conditions was solved, thereby improving battery safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- JIANGSU HIGHSTAR BATTERY MFG CO LTD
- Filing Date
- 2024-11-11
- Publication Date
- 2026-05-19
AI Technical Summary
Lithium-ion batteries pose safety hazards under high capacity and high power conditions, especially during short circuits. The inconsistent melting of the inner and outer tabs in a bipolar structure can lead to battery explosions or fires. Current technology cannot guarantee that the inner and outer tabs melt simultaneously during high-current discharge.
By calculating the welding positions of the inner and outer tabs and the tape wrapping depth, it is ensured that the heat dissipation of the inner and outer tabs is the same per unit cross-section and that they melt simultaneously during high current discharge. The encapsulation is carried out by acquiring parameter information, determining welding positions, and calculating tape wrapping depth.
This technology enables the inner and outer tabs to melt simultaneously during high-current discharge, improving battery safety and avoiding the risk of battery explosion or fire caused by inconsistent tab melting.
Smart Images
Figure CN122068258A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of battery safety technology, and more specifically to a method for packaging battery tabs and a packaging system for battery tabs. Background Technology
[0002] In recent years, the new energy sector has been booming, with lithium-ion rechargeable batteries receiving particular attention. Currently, lithium batteries are highly regarded for their electrical performance, with rapid progress in capacity, energy, and cycle life. However, along with the development of high-capacity, high-power batteries, safety issues have become increasingly apparent. These include overcharging, over-discharging, short circuits, compression, impacts from heavy objects, and overheating, all of which can lead to fires and explosions. Many factors influence the safety of lithium-ion batteries, with cell materials, manufacturing processes, structural design flaws, and energy density playing a decisive role.
[0003] Compared to traditional monotab cylindrical lithium-ion batteries, bitab structures have lower internal resistance and can withstand higher currents, making them primarily used in power batteries. Currently, cylindrical lithium-ion batteries mainly employ three types of internal tab structures: monotab, bitab, and all-tab. The monotab structure is the safest, but suffers from significant ohmic polarization, making it unsuitable for high-power batteries. While the all-tab structure exhibits lower ohmic polarization and is suitable for high-power batteries, its immature manufacturing process results in a higher probability of short circuits. Therefore, adopting a bitab structure reduces ohmic polarization while simultaneously improving short-circuit safety.
[0004] In a bipolar battery, during a low-resistance short circuit, the battery primarily relies on the positive electrode tab to melt to ensure safety. However, if the short-circuit current is critical, the tab melting process takes time, causing the battery to overheat. Multiple thermal fatigue sources form and expand within the heat-affected zone of the tab, leading to greater contact Joule heating. If other protection mechanisms fail to activate in time, the battery may explode. Furthermore, if one tab melts during a short circuit while the other remains intact, the sudden change in current shunting can also compromise the battery's short-circuit safety. Summary of the Invention
[0005] To address the aforementioned technical deficiencies, this invention provides a battery tab encapsulation method and system. The battery tab encapsulation method calculates the welding position of the inner tab based on the tab's parameter information, the electrode sheet's parameter information, and the welding parameter information. This welding position ensures that the heat dissipation between the inner and outer tabs at the welding point per unit cross-section is equal to that at the lower end of the ultrasonic weld. After welding the inner and outer tabs onto the electrode sheet, the depth of the tape wrapping the outer tab is determined based on the tab's parameter information and the electrode sheet's parameter information. This ensures that the inner and outer tabs melt simultaneously under high-current discharge. The battery tab encapsulation method proposed in this invention ensures that the heat generation of the inner and outer tabs is the same and that they melt simultaneously, thereby guaranteeing battery safety.
[0006] The first aspect of this invention provides a method for encapsulating battery tabs, wherein the battery tabs include an inner tab and an outer tab, and the inner tab and the outer tab are to be encapsulated on the same electrode sheet, the method comprising:
[0007] Obtain parameter information of the battery tabs, electrode sheets, and welding parameters to be packaged;
[0008] The welding position of the inner tab of the battery is determined based on the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information.
[0009] According to the welding position of the inner electrode ear, the inner electrode ear is welded to the electrode plate so that the heat dissipation between the welding position of the inner electrode ear and the outer electrode ear on a unit cross-section is the same as that between the lower end of the ultrasonic weld.
[0010] The depth of the wrapping tape for the outer tab is determined based on the parameter information of the battery tab and the electrode sheet.
[0011] Depending on the depth of the tape wrapping the outer tab, the tape is wrapped around the outer tab so that the inner tab and the outer tab melt simultaneously when the battery is discharged at a high current.
[0012] In this embodiment of the invention, the parameter information of the battery tabs includes: the size information of the inner tab, the size information of the outer tab, the distance between the inner tab and the outer tab, the resistivity of the inner tab, and the resistivity of the outer tab.
[0013] The parameter information of the electrode includes: the length of the electrode, the distance from the inner end of the electrode to the inner tab, and the distance from the outer tab to the outer end of the electrode;
[0014] The welding parameter information includes: the ohmic resistance of the ultrasonic welding of the inner electrode ear, the welding area of the ultrasonic welding of the inner electrode ear, the ohmic resistance of the ultrasonic welding of the outer electrode ear, the welding area of the ultrasonic welding of the outer electrode ear, the welding coefficient of the ultrasonic welding, the ohmic resistance of the laser welding of the cap connecting the upper end of the inner electrode ear, the welding area of the laser welding of the cap connecting the upper end of the inner electrode ear, the welding coefficient of the laser welding, the distance from the upper end of the ultrasonic welding of the outer electrode ear to the end of the electrode plate, and the distance between the lower end of the inner electrode ear weld and the upper end of the ultrasonic welding.
[0015] In this embodiment of the invention, determining the welding position of the outer tab based on the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information includes:
[0016] Calculate the resistance between the inner tab welding position and the upper end of the ultrasonic weld, as well as the resistance of the ultrasonic welded area of the inner tab.
[0017] Calculate the resistance between the outer electrode lug welding position and the upper end of the ultrasonic weld, as well as the resistance of the ultrasonic welded area of the outer electrode lug.
[0018] Calculate the current flowing through the inner electrode and the current flowing through the outer electrode;
[0019] The distance from the upper end of the ultrasonic weld of the inner electrode ear to the end of the electrode plate is calculated based on the resistance between the inner electrode ear welding position and the upper end of the ultrasonic weld, the resistance of the ultrasonic weld area of the inner electrode ear, the resistance between the outer electrode ear welding position and the upper end of the ultrasonic weld, the resistance of the ultrasonic weld area of the outer electrode ear, the current flowing through the inner electrode ear, and the current flowing through the outer electrode ear, so as to determine the welding position of the inner electrode ear.
[0020] In this embodiment of the invention, the resistance of the inner tab ultrasonic welding area includes: the contact resistance of the inner tab ultrasonic welding and the ohmic resistance of the inner tab ultrasonic welding.
[0021] The resistance of the ultrasonic welding area of the outer electrode includes: the contact resistance of the ultrasonic welding of the outer electrode and the ohmic resistance of the ultrasonic welding of the outer electrode.
[0022] In this embodiment of the invention, the method for calculating the contact resistance of the ultrasonic welding of the inner electrode lug is as follows:
[0023] The welding area of the ultrasonic welding of the inner electrode ear is calculated based on the welding length and welding width.
[0024] The contact resistance of the ultrasonic welding of the inner electrode ear is calculated based on the contact resistance coefficient of ultrasonic welding and the ohmic resistance of ultrasonic welding of the inner electrode ear.
[0025] In this embodiment of the invention, the formula for calculating the distance from the upper end of the inner electrode ear to the end of the electrode plate is as follows:
[0026]
[0027] Among them, I intI is the current flowing through the inner electrode. ext The current flowing through the inner electrode, w int w is the width of the inner pole ear. ext t represents the width of the outer ear. int t represents the thickness of the inner pole ear. ext R represents the thickness of the outer loop. inuwr R is the ohmic resistance of the ultrasonic welding position of the inner electrode tab. exuwr For the ohmic resistance of the ultrasonic welding position of the outer electrode tab, A inuw A represents the welding area of the inner electrode ear in ultrasonic welding. exuw Let be the welding area of the outer electrode ear in ultrasonic welding, K be the ultrasonic welding coefficient, b be the distance from the lower end of the inner electrode ear welding position to the upper end of the ultrasonic weld, and d be the welding area of the outer electrode ear in ultrasonic welding. inux d is the distance from the upper end of the inner electrode ear to the end of the electrode plate in ultrasonic welding. exux This refers to the distance from the upper end of the outer electrode ear to the end of the electrode plate during ultrasonic welding.
[0028] In this embodiment of the invention, determining the depth of the outer tab wrapping tape based on the parameter information of the battery tab and the parameter information of the electrode sheet includes:
[0029] Obtain the size information of the tape;
[0030] Calculate the current flowing through the inner electrode and the current flowing through the outer electrode based on the parameter information of the electrode, and obtain the current ratio of the inner electrode to the outer electrode.
[0031] Overcurrent tests were conducted on the inner tabs welded to the electrode sheet by selecting different depths of the inner tab wrapping tape. The depth of the outer tab wrapping tape corresponding to the depth of the inner tab wrapping tape when the inner tab melts was determined based on the current ratio of the inner tab to the outer tab.
[0032] In this embodiment of the invention, the method for calculating the current flowing through the inner electrode is as follows:
[0033] The current flowing through the inner electrode is calculated based on the battery current, electrode length, distance between the inner end of the electrode and the inner tab, and distance between the inner tab and the outer tab.
[0034] The method for calculating the current flowing through the outer electrode is as follows:
[0035] The current flowing through the outer electrode is calculated based on the battery current, electrode length, distance between the inner and outer electrodes, and distance between the outer electrode and the outer end of the electrode.
[0036] In this embodiment of the invention, the formula for calculating the current flowing through the inner electrode is:
[0037]
[0038] The formula for calculating the current flowing through the outer electrode is:
[0039]
[0040] Among them, I int I is the current flowing through the inner electrode. ext L is the current flowing through the inner electrode, L is the length of the electrode, L1 is the distance between the inner end of the electrode and the inner tab, L2 is the distance between the inner tab and the outer tab, and L3 is the distance between the outer tab and the outer end of the electrode.
[0041] A second aspect of the present invention provides a battery tab packaging system, the system comprising:
[0042] The parameter information acquisition module is used to acquire the parameter information of the battery tabs to be packaged, the parameter information of the electrode sheets, and the welding parameter information.
[0043] The welding position determination module is used to determine the welding position of the inner tab of the battery tab based on the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information.
[0044] The welding module is used to weld the inner electrode tab onto the electrode plate according to the welding position of the inner electrode tab, so that the heat dissipation between the welding position of the inner and outer electrode tabs per unit cross-section and the lower end of the ultrasonic weld is the same.
[0045] The wrapping depth determination module is used to determine the depth of the wrapping tape for the outer tab based on the parameter information of the battery tab and the parameter information of the electrode sheet;
[0046] The tape wrapping module is used to wrap the tape around the outer electrode tab according to the depth of the tape wrapping, so that the inner electrode tab and the outer electrode tab melt simultaneously when the battery is discharged with a large current.
[0047] A third aspect of the present invention provides a computer device, comprising:
[0048] Memory, which stores computer programs;
[0049] A processor for executing the computer program to implement the battery tab packaging method as described above.
[0050] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the battery tab encapsulation method as described above.
[0051] The battery tab encapsulation method calculates the welding position of the inner tab based on the parameters of the tab, the electrode sheet, and the welding parameters. This welding position ensures that the heat dissipation between the inner and outer tabs at the weld point and the lower end of the ultrasonic weld is the same per unit cross-section. After welding the inner and outer tabs onto the electrode sheet, the depth of the tape wrapping the outer tab is determined based on the tab and electrode sheet parameters to ensure that the inner and outer tabs melt simultaneously under high current discharge. This battery tab encapsulation method ensures that the heat generation of the inner and outer tabs is the same and that they melt simultaneously, thus guaranteeing battery safety.
[0052] Other features and advantages of the technical solution of the present invention will be described in detail in the following detailed embodiments section. Attached Figure Description
[0053] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:
[0054] Figure 1 This is a flowchart of a battery tab encapsulation method provided in an embodiment of the present invention;
[0055] Figure 2 This is an unfolded view of the battery electrode sheet provided in an embodiment of the present invention;
[0056] Figure 3 This is a schematic diagram of the current shunting of the battery electrode tabs provided in an embodiment of the present invention;
[0057] Figure 4 This is a schematic diagram of the battery tab structure provided in an embodiment of the present invention. Figure 1 ;
[0058] Figure 5 This is a schematic diagram of the battery tab structure provided in an embodiment of the present invention. Figure 2 ;
[0059] Figure 6 This is an assembly diagram of the battery tabs provided in an embodiment of the present invention;
[0060] Figure 7 This is a schematic diagram of the packaging system for battery tabs provided in an embodiment of the present invention;
[0061] Figure 8 This is a graph showing the relationship between current and fusing time under different tab sizes and tape wrapping, as provided in this embodiment. Detailed Implementation
[0062] To make the technical solutions and advantages of the embodiments of the present invention clearer, the exemplary embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.
[0063] 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," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are 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.
[0064] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0065] In this invention, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "linking," and "fixing" 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, an electrical connection, or a connection that allows communication between them; 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. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0066] In the process of developing this invention, the inventors discovered that the new energy field has been booming in recent years, with lithium-ion secondary batteries receiving particular attention. Currently, lithium batteries are highly regarded for their electrical performance, with rapid progress in capacity, energy, and cycle life. However, along with the development of high-capacity, high-power batteries, safety issues related to lithium-ion batteries have become increasingly apparent. These issues include overcharging, over-discharging, short circuits, compression, impacts from heavy objects, and overheating, all of which can lead to fires and explosions. Many factors influence the safety of lithium-ion batteries, with cell materials, manufacturing processes, structural defects in battery design, and energy density playing a decisive role.
[0067] Compared to traditional single-tab cylindrical lithium-ion batteries, bitab structures have lower internal resistance and can withstand higher currents, making them primarily used in power batteries. Currently, cylindrical lithium-ion batteries mainly employ three types of internal tab structures: single-tab, bitab, and full-tab. The single-tab structure is the safest, but suffers from severe ohmic polarization, making it unsuitable for high-power batteries. While the full-tab structure exhibits lower ohmic polarization and is suitable for high-power batteries, its immature manufacturing process results in a higher probability of short-circuit failure. Therefore, the bitab structure reduces ohmic polarization and improves short-circuit safety. In the event of a low-resistance short circuit, bitab batteries primarily rely on the positive tab to melt to ensure battery safety. However, if the short-circuit current reaches a critical value, the tab melting process takes time, causing the battery to overheat. Multiple thermal fatigue sources form and expand within the heat-affected zone of the tab, leading to greater contact Joule heating. If other protection mechanisms fail to activate in time, the battery may explode. In addition, if one tab melts during a short circuit while the other tab does not, the sudden change in battery current shunting will also affect the safety of the battery short circuit.
[0068] To address the aforementioned problems, this invention provides a method for encapsulating battery tabs. The battery tabs include an inner tab and an outer tab, which are encapsulated on the same electrode sheet. The method includes: acquiring parameter information of the battery tab to be encapsulated, parameter information of the electrode sheet, and welding parameter information; determining the welding position of the inner tab based on the parameter information of the battery tab, the electrode sheet, and the welding parameter information; welding the inner tab to the electrode sheet according to the welding position of the inner tab, such that the heat dissipation between the welding position of the inner tab and the outer tab and the lower end of the ultrasonic weld is the same per unit cross-section; determining the depth of the wrapping tape of the outer tab based on the parameter information of the battery tab and the electrode sheet; and wrapping the outer tab with tape according to the depth of the wrapping tape, such that the inner tab and the outer tab melt simultaneously when the battery undergoes high-current discharge. The battery tab encapsulation method calculates the welding position of the inner tab based on the parameters of the tab, the electrode sheet, and the welding parameters. This welding position ensures that the heat dissipation between the inner and outer tabs at the weld point and the lower end of the ultrasonic weld is the same per unit cross-section. After welding the inner and outer tabs onto the electrode sheet, the depth of the tape wrapping the outer tab is determined based on the tab and electrode sheet parameters to ensure that the inner and outer tabs melt simultaneously under high current discharge. This battery tab encapsulation method ensures that the heat generation of the inner and outer tabs is the same and that they melt simultaneously, thus guaranteeing battery safety.
[0069] Figure 1 This is a flowchart of a battery tab encapsulation method provided in an embodiment of the present invention. Figure 1As shown in this embodiment, a battery tab encapsulation method is provided. The tab includes an inner tab and an outer tab, which are encapsulated on the same electrode sheet. The method includes:
[0070] S1. Obtain parameter information of battery tabs, electrode sheets, and welding parameters;
[0071] S2. Calculate the welding position of the inner tab based on the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information;
[0072] S3. Based on the calculated welding position of the inner electrode ear, weld the inner electrode ear onto the electrode plate so that the heat dissipation between the welding position of the inner electrode ear and the outer electrode ear on a unit cross-section is the same as that between the lower end of the ultrasonic weld.
[0073] S4. Determine the depth of the wrapping tape for the outer tab based on the parameter information of the battery tab and the electrode sheet;
[0074] S5. Based on the depth of the tape wrapping the outer electrode tab, wrap the tape around the outer electrode tab so that the inner electrode tab and the outer electrode tab melt simultaneously when the battery is discharging at a high current.
[0075] Figure 2 This is an unfolded view of the battery electrode provided in an embodiment of the present invention. Figure 3 This is a schematic diagram of the current shunting of the battery electrode tabs provided in an embodiment of the present invention, as shown below. Figure 2-3 As shown, the inner electrode and the outer electrode are encapsulated on the same positive electrode plate.
[0076] In step S1, the parameter information of the battery tabs includes: the size information of the inner tab, the size information of the outer tab, the distance between the inner tab and the outer tab, the resistivity of the inner tab, and the resistivity of the outer tab.
[0077] The parameter information of the electrode includes: the length of the electrode, the distance from the inner end of the electrode to the inner tab, and the distance from the outer tab to the outer end of the electrode;
[0078] The welding parameter information includes: the ohmic resistance of the ultrasonic welding of the inner electrode ear, the welding area of the ultrasonic welding of the inner electrode ear, the ohmic resistance of the ultrasonic welding of the outer electrode ear, the welding area of the ultrasonic welding of the outer electrode ear, the welding coefficient of the ultrasonic welding, the ohmic resistance of the laser welding of the cap connecting the upper end of the inner electrode ear, the welding area of the laser welding of the cap connecting the upper end of the inner electrode ear, the welding coefficient of the laser welding, the distance from the upper end of the ultrasonic welding of the outer electrode ear to the end of the electrode plate, and the distance between the lower end of the inner electrode ear weld and the upper end of the ultrasonic welding.
[0079] Figure 4 This is a schematic diagram of the battery tab structure provided in an embodiment of the present invention. Figure 1 , Figure 5 This is a schematic diagram of the battery tab structure provided in an embodiment of the present invention. Figure 2 ,like Figure 4-5 As shown, specifically, the size information of the inner electrode ear includes: the length l of the inner electrode ear. int The width w of the inner pole ear int And the thickness t of the inner ear int The size information of the outer electrode includes: the length l of the outer electrode. ext The width w of the inner pole ear ext And the thickness t of the inner ear ext The distance between the inner and outer electrodes is L2, and the resistivity of the inner electrode is the same as that of the outer electrode, which is ρ.
[0080] The length of the electrode is L, the distance from the inner end of the electrode to the inner tab is L1, and the distance from the outer tab to the outer end of the electrode is L3.
[0081] The ohmic resistance of the ultrasonic welding of the inner electrode lug is R. inuwr The welding area of the inner electrode ear in ultrasonic welding is A. inuw The ohmic resistance of the ultrasonic welding of the outer electrode tab is R. exuwr The welding area of the inner electrode ear in ultrasonic welding is A. exuw The welding coefficient of ultrasonic welding is K, and the ohmic resistance of laser welding on the upper end of the inner electrode connecting to the cap is R. inlwcr The laser welding area of the cap connecting the upper end of the inner electrode lug is A. inlwcr The welding coefficient for laser welding is N, and the distance from the upper end of the outer electrode tab to the end of the electrode plate in ultrasonic welding is d. exux The distance between the lower end of the inner electrode lug and the upper end of the ultrasonic weld is b.
[0082] In this embodiment, the following parameters are also provided:
[0083] The battery's internal impedance is R, the current flowing through the battery is I, the heating time is t, the heat generated by the inner tab is Q1 and Q2, the heat generated by the outer tab is Q3 and Q4, the weld width between the inner and outer tabs is e, the weld length between the inner and outer tabs is c, and the width of the tape wrapping the inner tab is f. in The width of the tape wrapping the outer electrode ear is f. ex The depth of the inner electrode ear wrapping tape (i.e., the distance from the bottom of the inner electrode ear wrapping tape to the upper edge of the electrode plate) is d. intape The depth of the tape wrapping around the outer electrode (i.e., the distance from the bottom of the tape wrapping around the outer electrode to the upper edge of the electrode plate) is d. extape The distance between the upper end of the weld and the laser weld is 'a', the distance between the lower end of the weld and the upper end of the ultrasonic weld is 'b', the distance from the lower end of the inner electrode tab to the upper edge of the inner electrode tab is 'm', and the effective area of the weld is 'A'. In this embodiment, the weld is the intersection area of the laser weld and the ultrasonic weld.
[0084] Furthermore, the calculation can be performed based on the above parameter information:
[0085] Ohmic resistance of the inner tab:
[0086] Ohmic resistance of the outer electrode:
[0087] Contact resistance of ultrasonic welding of inner electrode lugs:
[0088] Contact resistance of ultrasonic welding of outer electrode lugs:
[0089] Laser welding contact resistance of the cap connected to the upper end of the inner electrode tab:
[0090] The current flowing through the inner electrode ear is:
[0091] The current flowing through the outer electrode ear is:
[0092] The ratio of the current flowing through the inner electrode to the current flowing through the outer electrode is:
[0093] From the above formula, we can know that the Joule heat generated by the inner electrode is:
[0094]
[0095] The Joule heat generated by the outer pole ear is:
[0096]
[0097] If the inner and outer tabs generate the same amount of heat per unit cross-section, then the battery's bipolar structure is the most stable, i.e.:
[0098]
[0099] Furthermore, based on the fact that the inner and outer tabs generate the same amount of heat per unit interface, it can be deduced that if the heat dissipation between the welded ends of the ultrasonic weld is the same per unit cross-section, then the tab system is more stable. That is:
[0100]
[0101] In step S2, calculating the welding position of the outer electrode tab based on the obtained parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information includes:
[0102] S21. Calculate the resistance between the inner tab welding position and the upper end of the ultrasonic weld, as well as the resistance of the ultrasonic welded area of the inner tab.
[0103] S22. Calculate the resistance between the outer electrode lug welding position and the upper end of the ultrasonic weld, as well as the resistance of the outer electrode lug ultrasonic weld area;
[0104] S23. Calculate the current flowing through the inner electrode and the current flowing through the outer electrode;
[0105] S24. Based on the calculated resistance between the inner electrode lug welding position and the upper end of the ultrasonic weld, the resistance of the inner electrode lug ultrasonic weld area, the resistance between the outer electrode lug welding position and the upper end of the ultrasonic weld, the resistance of the outer electrode lug ultrasonic weld area, the current flowing through the inner electrode lug, and the current flowing through the outer electrode lug, the distance from the upper end of the inner electrode lug ultrasonic weld to the end of the electrode plate is calculated to determine the welding position of the inner electrode lug.
[0106] Furthermore, the resistance of the inner tab ultrasonic welding area includes: the contact resistance of the inner tab ultrasonic welding and the ohmic resistance of the inner tab ultrasonic welding.
[0107] The resistance of the ultrasonic welding area of the outer electrode includes: the contact resistance of the ultrasonic welding of the outer electrode and the ohmic resistance of the ultrasonic welding of the outer electrode.
[0108] Furthermore, the method for calculating the contact resistance of the ultrasonic welding of the inner electrode lug is as follows:
[0109] The welding area of the ultrasonic welding of the inner electrode ear is calculated based on the welding length and welding width.
[0110] The formula for calculating the welding area of ultrasonic welding is as follows:
[0111] A inuw =w inuw ×h inuw ;
[0112] Among them, w inuw h is the weld width for ultrasonic welding of the inner electrode lug. inuw The welding length for ultrasonic welding of the inner electrode lug.
[0113] The contact resistance of the ultrasonic welding is calculated based on the welding area of the inner electrode ear, the contact resistance coefficient of the ultrasonic welding, and the ohmic resistance of the inner electrode ear ultrasonic welding.
[0114] In step S24, the formula for calculating the distance from the upper end of the inner electrode ear to the end of the electrode plate in ultrasonic welding is as follows:
[0115]
[0116] Among them, I int I is the current flowing through the inner electrode. ext The current flowing through the inner electrode, w int w is the width of the inner pole ear. ext t represents the width of the outer ear. int t represents the thickness of the inner pole ear.ext R represents the thickness of the outer loop. inuwr R is the ohmic resistance of the ultrasonic welding position of the inner electrode tab. exuwr For the ohmic resistance of the ultrasonic welding position of the outer electrode tab, A inuw A represents the welding area of the inner electrode ear in ultrasonic welding. exuw Let be the welding area of the outer electrode ear in ultrasonic welding, K be the ultrasonic welding coefficient, b be the distance from the lower end of the inner electrode ear welding position to the upper end of the ultrasonic weld, and d be the welding area of the outer electrode ear in ultrasonic welding. inux d is the distance from the upper end of the inner electrode ear to the end of the electrode plate in ultrasonic welding. exux This refers to the distance from the upper end of the outer electrode ear to the end of the electrode plate during ultrasonic welding.
[0117] In this embodiment, the welding position of the battery tab can be modeled by acquiring the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information, thus obtaining a mathematical model;
[0118] Furthermore, this embodiment provides the following mathematical model:
[0119] 3.72b + 6.33*(d) exux -d inux ) = 90.77;
[0120] This can be achieved by inputting a set value for b and d into the mathematical model. exux The set value is used to solve d. inux This is to obtain the distance from the upper end of the inner electrode ear to the end of the electrode plate in the ultrasonic welding process.
[0121] Therefore, in this embodiment, by inputting d exux The set value determines the distance from the upper end of the outer electrode tab to the end of the electrode plate in ultrasonic welding, based on the set d. exux The distance from the upper end of the inner tab to the electrode sheet is calculated based on the set value, thereby determining the welding positions of the inner tab and outer tab of the battery. Based on the distance from the upper end of the outer tab to the end of the electrode sheet and the distance from the upper end of the inner tab to the electrode sheet, the inner tab and outer tab are welded onto the electrode sheet.
[0122] In step S4, the depth d of the wrapping tape for the outer electrode tab is determined based on the parameter information of the battery tab and the parameter information of the electrode sheet. extape ,include:
[0123] S41. Obtain the size information of the tape;
[0124] S42. Calculate the current flowing through the inner tab and the current flowing through the outer tab based on the parameter information of the battery tabs, and obtain the current ratio of the inner tab to the outer tab;
[0125] S43. Overcurrent tests are conducted on the inner tabs welded to the electrode sheet using different depths of the inner tab wrapping tape. Based on the current ratio between the inner and outer tabs, the corresponding outer tab wrapping tape depth d at the point of melting of the inner tab is determined. extape .
[0126] In step S32, the method for calculating the current flowing through the inner electrode is as follows:
[0127] The current flowing through the inner electrode is calculated based on the battery current, electrode length, distance between the inner end of the electrode and the inner tab, and distance between the inner tab and the outer tab.
[0128] The method for calculating the current flowing through the outer electrode is as follows:
[0129] The current flowing through the outer electrode is calculated based on the battery current, electrode length, distance between the inner and outer electrodes, and distance between the outer electrode and the outer end of the electrode.
[0130] In this embodiment, the formula for calculating the current flowing through the inner electrode is:
[0131]
[0132] The formula for calculating the current flowing through the outer electrode is:
[0133]
[0134] Among them, I int I is the current flowing through the inner electrode. ext L is the current flowing through the inner electrode, L is the length of the electrode, L1 is the distance between the inner end of the electrode and the inner tab, L2 is the distance between the inner tab and the outer tab, and L3 is the distance between the outer tab and the outer end of the electrode.
[0135] Specifically, the detailed steps for the overcurrent test provided in this implementation are as follows:
[0136] For a tab system at the same assembly position, tapes of different sizes and wrapping depths will have different tab melting times under the same current. Therefore, after determining the tab size and welding position, select a suitable high-temperature tape size and wrapping depth to make both tabs melt simultaneously and improve short-circuit safety.
[0137] To ensure that the battery's positive electrode tabs melt simultaneously under high-current discharge, a separate overcurrent testing system was used to test the designed tabs. Figure 5 To test the series circuit of the overcurrent system, the following requirements are specified:
[0138] 1. Prepare one charging and discharging device, one connecting wire, one large-capacity square battery cell, positive electrode tabs of different models, brown high-temperature tape, and unformed positive electrode sheets;
[0139] 2. The electrode tab to be tested and the current collector of the positive electrode plate are ultrasonically welded, and an aluminum connecting piece is laser welded to the end of the positive electrode tab to obtain the electrode tab component to be tested.
[0140] 3. The electrode component to be tested is the inner electrode with the assembled and shaped positioning dimensions and the depth of the wrapping tape already determined. Then, based on the melting of the inner electrode, the current ratio is calculated, and the depth of the wrapping tape of the assembled outer electrode is determined.
[0141] 4. Connect the charging / discharging device, the square battery cell, and the test tab component in series using wires, and clamp the large flat clips onto the aluminum connector and aluminum foil respectively.
[0142] 5. To ensure testing safety, a high-capacity, high-temperature-treated square battery (capacity at least 200Ah) was used as protection. A certain large current was applied to test the overcurrent capability of the aluminum tabs of the sample, and the overcurrent capability of the tab system was analyzed in detail.
[0143] The inner and outer tabs are respectively made of width f in =11mm,f ex =13mm tape wrapping, the inner tab is designed with a tape wrapping depth of d. intape =1mm. To ensure that both tabs on the positive terminal of the battery melt simultaneously under high-current discharge, the above equipment is used for testing. The tab component under test is the inner tab, whose assembly, shaping, and positioning dimensions and the depth of the wrapping tape have been determined. Then, based on the melting of the inner tab, the current ratio is calculated, and the depth d of the wrapping tape of the assembled outer tab is determined. extape .
[0144] Assemble the 5.0mm electrode tabs according to the above inner electrode tab shaping and positioning dimensions, and measure the electrode tab tape wrapping depth d. intape =1mm, the average melting time t (20 groups of tested samples) under different currents I was plotted as curves, and the wrapping depth of the 3mm outer electrode tab was 1mm. <d extape For samples <7mm, testing was conducted. The curve exhibits a power function correlation, and can be fitted using a power function. The fitting results are as follows. Figure 8 As shown, Figure 8 This embodiment shows the relationship between current and fusing time under different tab sizes and tape wrapping conditions. It reveals that when the outer tab is 3mm thick and the wrapping depth is 5mm (11mm tape), the overcurrent resistance is similar to that of a 5mm thick tab with a wrapping depth of 1mm (13mm tape). Therefore, using the above parameters, the designed bipolar tab assembly diagram is as follows. Figure 6 , Figure 6 This is an assembly diagram of the battery tabs provided in an embodiment of the present invention.
[0145] After assembling the positive and negative tabs according to the above method, a short-circuit test was performed on the assembled battery. The designed battery was subjected to single-cell short-circuit tests at 100 SOC, with 10mΩ and 20mΩ respectively. The test results are shown in Table 2 below:
[0146] Table 2: Specific details of single-unit room temperature short circuit
[0147]
[0148] Figure 7 This is a schematic diagram of the packaging system for battery tabs provided in an embodiment of the present invention. Figure 7 As shown, this embodiment provides a battery tab packaging system, including:
[0149] The parameter information acquisition module is used to acquire the parameter information of the tab to be packaged, the parameter information of the electrode sheet, and the welding parameter information;
[0150] The welding position determination module is used to determine the welding position of the inner tab of the battery tab based on the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information.
[0151] The welding module is used to weld the inner electrode tab onto the electrode plate according to the welding position of the inner electrode tab, so that the heat dissipation between the welding position of the inner and outer electrode tabs per unit cross-section and the lower end of the ultrasonic weld is the same.
[0152] The wrapping depth determination module is used to determine the depth of the wrapping tape for the outer tab based on the parameter information of the battery tab and the parameter information of the electrode sheet;
[0153] The tape wrapping module is used to wrap the tape around the outer electrode tab according to the depth of the tape wrapping, so that the inner electrode tab and the outer electrode tab melt simultaneously when the battery is discharged with a large current.
[0154] In this embodiment, the parameter information of the battery tabs includes: the size information of the inner tab, the size information of the outer tab, the distance between the inner tab and the outer tab, the resistivity of the inner tab, and the resistivity of the outer tab;
[0155] The parameter information of the electrode includes: the length of the electrode, the distance from the inner end of the electrode to the inner tab, and the distance from the outer tab to the outer end of the electrode;
[0156] The welding parameter information includes: the ohmic resistance of the ultrasonic welding of the inner electrode lug, the welding area of the ultrasonic welding of the inner electrode lug, the ohmic resistance of the ultrasonic welding of the outer electrode lug, the welding area of the ultrasonic welding of the outer electrode lug, the welding coefficient of the ultrasonic welding, the ohmic resistance of the laser welding of the cap connecting the upper end of the inner electrode lug, the welding area of the laser welding of the cap connecting the upper end of the inner electrode lug, the welding coefficient of the laser welding, the distance from the upper end of the ultrasonic welding of the outer electrode lug to the end of the electrode plate, and the distance from the lower end of the welded inner electrode lug to the upper end of the ultrasonic welding. The dimensional information of the inner electrode lug includes: the length l of the inner electrode lug. int The width w of the inner pole ear int And the thickness t of the inner ear int The size information of the outer electrode includes: the length l of the outer electrode. ext The width w of the inner pole ear ext And the thickness t of the inner ear ext The distance between the inner and outer electrodes is L2, and the resistivity of the inner electrode is the same as that of the outer electrode, which is ρ.
[0157] The length of the electrode is L, the distance from the inner end of the electrode to the inner tab is L1, and the distance from the outer tab to the outer end of the electrode is L3.
[0158] The ohmic resistance of the ultrasonic welding of the inner electrode lug is R. inuwr The welding area of the inner electrode ear in ultrasonic welding is A. inuw The ohmic resistance of the ultrasonic welding of the outer electrode tab is R. exuwr The welding area of the inner electrode ear in ultrasonic welding is A. exuw The welding coefficient of ultrasonic welding is K, and the ohmic resistance of laser welding on the upper end of the inner electrode connecting to the cap is R. inlwcr The laser welding area of the cap connecting the upper end of the inner electrode lug is A. inlwcr The welding coefficient for laser welding is N, and the distance from the upper end of the outer electrode tab to the end of the electrode plate in ultrasonic welding is d. exux The distance between the lower end of the inner electrode lug and the upper end of the ultrasonic weld is b.
[0159] In this embodiment, the following parameters are also provided:
[0160] The battery's internal impedance is R, the current flowing through the battery is I, the heating time is t, the heat generated by the inner tab is Q1 and Q2, the heat generated by the outer tab is Q3 and Q4, the weld width between the inner and outer tabs is e, the weld length between the inner and outer tabs is c, and the width of the tape wrapping the inner tab is f. in The width of the tape wrapping the outer electrode ear is f. ex The depth of the inner electrode ear wrapping tape (i.e., the distance from the bottom of the inner electrode ear wrapping tape to the upper edge of the electrode plate) is d. intape The depth of the tape wrapping around the outer electrode (i.e., the distance from the bottom of the tape wrapping around the outer electrode to the upper edge of the electrode plate) is d. extapeThe distance between the upper end of the weld and the laser weld is 'a', the distance between the lower end of the weld and the upper end of the ultrasonic weld is 'b', the distance from the lower end of the inner electrode tab to the upper edge of the inner electrode tab is 'm', and the effective area of the weld is 'A'. In this embodiment, the weld is the intersection area of the laser weld and the ultrasonic weld.
[0161] Furthermore, the calculation can be performed based on the above parameter information:
[0162] Ohmic resistance of the inner tab:
[0163] Ohmic resistance of the outer electrode:
[0164] Contact resistance of ultrasonic welding of inner electrode lugs:
[0165] Contact resistance of ultrasonic welding of outer electrode lugs:
[0166] Laser welding contact resistance of the cap connected to the upper end of the inner electrode tab:
[0167] The current flowing through the inner electrode ear is:
[0168] The current flowing through the outer electrode ear is:
[0169] The ratio of the current flowing through the inner electrode to the current flowing through the outer electrode is:
[0170] From the above formula, we can know that the Joule heat generated by the inner electrode is:
[0171]
[0172] The Joule heat generated by the outer pole ear is:
[0173]
[0174] If the inner and outer tabs generate the same amount of heat per unit cross-section, then the battery's bipolar structure is the most stable, i.e.:
[0175]
[0176] Furthermore, based on the fact that the inner and outer tabs generate the same amount of heat per unit interface, it can be deduced that if the heat dissipation between the welded ends of the ultrasonic weld is the same per unit cross-section, then the tab system is more stable. That is:
[0177]
[0178] The first calculation module is specifically used to: calculate the resistance between the inner tab welding position and the upper end of the ultrasonic weld, as well as the resistance of the inner tab ultrasonic weld area;
[0179] Calculate the resistance between the outer electrode lug welding position and the upper end of the ultrasonic weld, as well as the resistance of the ultrasonic welded area of the outer electrode lug.
[0180] Calculate the current flowing through the inner electrode and the current flowing through the outer electrode;
[0181] The distance from the upper end of the ultrasonic weld of the inner electrode ear to the end of the electrode plate is calculated based on the resistance between the inner electrode ear welding position and the upper end of the ultrasonic weld, the resistance of the ultrasonic weld area of the inner electrode ear, the resistance between the outer electrode ear welding position and the upper end of the ultrasonic weld, the resistance of the ultrasonic weld area of the outer electrode ear, the current flowing through the inner electrode ear, and the current flowing through the outer electrode ear, so as to determine the welding position of the inner electrode ear.
[0182] Furthermore, the resistance of the inner tab ultrasonic welding area includes: the contact resistance of the inner tab ultrasonic welding and the ohmic resistance of the inner tab ultrasonic welding.
[0183] The resistance of the ultrasonic welding area of the outer electrode includes: the contact resistance of the ultrasonic welding of the outer electrode and the ohmic resistance of the ultrasonic welding of the outer electrode.
[0184] Furthermore, the method for calculating the contact resistance of the ultrasonic welding of the inner electrode lug is as follows:
[0185] The welding area of the ultrasonic welding of the inner electrode ear is calculated based on the welding length and welding width.
[0186] The formula for calculating the welding area of ultrasonic welding is as follows:
[0187] A inuw =w inuw ×h inuw ;
[0188] Among them, w inuw h is the weld width for ultrasonic welding of the inner electrode lug. inuw The welding length for ultrasonic welding of the inner electrode lug.
[0189] The contact resistance of ultrasonic welding is calculated based on the contact resistance coefficient of ultrasonic welding and the ohmic resistance of ultrasonic welding of the inner electrode lug.
[0190] The formula for calculating the distance from the upper end of the inner electrode ear to the end of the electrode plate in ultrasonic welding is as follows:
[0191]
[0192] Among them, I int I is the current flowing through the inner electrode. ext The current flowing through the inner electrode, w int w is the width of the inner pole ear. extt represents the width of the outer ear. int t represents the thickness of the inner pole ear. ext R represents the thickness of the outer loop. inuwr R is the ohmic resistance of the ultrasonic welding position of the inner electrode tab. exuwr For the ohmic resistance of the ultrasonic welding position of the outer electrode tab, A inuw A represents the welding area of the inner electrode ear in ultrasonic welding. exuw Let be the welding area of the outer electrode ear in ultrasonic welding, K be the ultrasonic welding coefficient, b be the distance from the lower end of the inner electrode ear welding position to the upper end of the ultrasonic weld, and d be the welding area of the outer electrode ear in ultrasonic welding. inux d is the distance from the upper end of the inner electrode ear to the end of the electrode plate in ultrasonic welding. exux This refers to the distance from the upper end of the outer electrode ear to the end of the electrode plate during ultrasonic welding.
[0193] In this embodiment, the welding position of the battery tab can be modeled by acquiring the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information, thus obtaining a mathematical model;
[0194] Furthermore, this embodiment provides the following mathematical model:
[0195] 3.72b + 6.33*(d) exux -d inux ) = 90.77;
[0196] This can be achieved by inputting a set value for b and d into the mathematical model. exux The set value is used to solve d. inux This is to obtain the distance from the upper end of the inner electrode ear to the end of the electrode plate in the ultrasonic welding process.
[0197] The second calculation module is specifically used to: obtain the size information of the tape;
[0198] Calculate the current flowing through the inner electrode and the current flowing through the outer electrode based on the parameter information of the electrode, and obtain the current ratio of the inner electrode to the outer electrode.
[0199] Overcurrent tests were conducted on the inner tabs welded to the electrode sheet by selecting different depths of the inner tab wrapping tape. The depth of the outer tab wrapping tape corresponding to the depth of the inner tab wrapping tape when the inner tab melts was determined based on the current ratio of the inner tab to the outer tab.
[0200] A third aspect of the present invention provides a computer device, comprising:
[0201] Memory, which stores computer programs;
[0202] A processor for executing the computer program to implement the battery tab packaging method as described above.
[0203] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the battery tab encapsulation method as described above.
[0204] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of the present invention can be implemented using various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.
[0205] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0206] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0207] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0208] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.
[0209] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.
Claims
1. A method for packaging battery tabs, characterized in that, The battery tabs include an inner tab and an outer tab, which need to be encapsulated on the same electrode sheet. The method includes: Obtain parameter information of the battery tabs, electrode sheets, and welding parameters to be packaged; The welding position of the inner tab of the battery is determined based on the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information. According to the welding position of the inner electrode ear, the inner electrode ear is welded to the electrode plate so that the heat dissipation between the welding position of the inner electrode ear and the outer electrode ear on a unit cross-section is the same as that between the lower end of the ultrasonic weld. The depth of the wrapping tape for the outer tab is determined based on the parameter information of the battery tab and the electrode sheet. Depending on the depth of the tape wrapping the outer tab, the tape is wrapped around the outer tab so that the inner tab and the outer tab melt simultaneously when the battery is discharged at a high current.
2. The battery tab encapsulation method according to claim 1, characterized in that, The parameter information of the battery tabs includes: the size information of the inner tab, the size information of the outer tab, the distance between the inner tab and the outer tab, the resistivity of the inner tab, and the resistivity of the outer tab. The parameter information of the electrode includes: the length of the electrode, the distance from the inner end of the electrode to the inner tab, and the distance from the outer tab to the outer end of the electrode; The welding parameter information includes: the ohmic resistance of the ultrasonic welding of the inner electrode ear, the welding area of the ultrasonic welding of the inner electrode ear, the ohmic resistance of the ultrasonic welding of the outer electrode ear, the welding area of the ultrasonic welding of the outer electrode ear, the welding coefficient of the ultrasonic welding, the ohmic resistance of the laser welding of the cap connecting the upper end of the inner electrode ear, the welding area of the laser welding of the cap connecting the upper end of the inner electrode ear, the welding coefficient of the laser welding, the distance from the upper end of the ultrasonic welding of the outer electrode ear to the end of the electrode plate, and the distance between the lower end of the inner electrode ear weld and the upper end of the ultrasonic welding.
3. The battery tab encapsulation method according to claim 2, characterized in that, Determining the welding position of the inner tab of the battery electrode based on the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information includes: Calculate the resistance between the inner tab welding position and the upper end of the ultrasonic weld, as well as the resistance of the ultrasonic welded area of the inner tab. Calculate the resistance between the outer electrode lug welding position and the upper end of the ultrasonic weld, as well as the resistance of the ultrasonic welded area of the outer electrode lug. Calculate the current flowing through the inner electrode and the current flowing through the outer electrode; The welding position of the inner electrode ear is determined based on the resistance between the inner electrode ear welding position and the upper end of the ultrasonic weld, the resistance of the inner electrode ear ultrasonic weld area, the resistance between the outer electrode ear welding position and the upper end of the ultrasonic weld, the resistance of the outer electrode ear ultrasonic weld area, the current flowing through the inner electrode ear, and the distance from the upper end of the inner electrode ear ultrasonic weld to the end of the electrode plate calculated based on the current flowing through the outer electrode ear.
4. The battery tab encapsulation method according to claim 3, characterized in that, The resistance of the ultrasonic welding area of the inner electrode includes: the contact resistance of the ultrasonic welding of the inner electrode and the ohmic resistance of the ultrasonic welding of the inner electrode. The resistance of the ultrasonic welding area of the outer electrode includes: the contact resistance of the ultrasonic welding of the outer electrode and the ohmic resistance of the ultrasonic welding of the outer electrode.
5. The battery tab encapsulation method according to claim 4, characterized in that, The method for calculating the contact resistance of the ultrasonic welding of the inner electrode lug is as follows: The welding area of the ultrasonic welding of the inner electrode ear is calculated based on the welding length and welding width. The contact resistance of the ultrasonic welding of the inner electrode ear is calculated based on the welding area, the contact resistance coefficient of the ultrasonic welding, and the ohmic resistance of the ultrasonic welding of the inner electrode ear.
6. The battery tab encapsulation method according to claim 5, characterized in that, The formula for calculating the distance from the upper end of the inner electrode ear to the end of the electrode plate in ultrasonic welding is as follows: Among them, I int I is the current flowing through the inner electrode. ext The current flowing through the inner electrode, w int w is the width of the inner pole ear. ext t represents the width of the outer ear. int t represents the thickness of the inner pole ear. ext R represents the thickness of the outer loop. inuwr R is the ohmic resistance of the ultrasonic welding position of the inner electrode tab. exuwr For the ohmic resistance of the ultrasonic welding position of the outer electrode tab, A inuw A represents the welding area of the inner electrode ear in ultrasonic welding. exuw Let be the welding area of the outer electrode ear in ultrasonic welding, K be the ultrasonic welding coefficient, b be the distance from the lower end of the inner electrode ear welding position to the upper end of the ultrasonic weld, and d be the welding area of the outer electrode ear in ultrasonic welding. inux d is the distance from the upper end of the inner electrode ear to the end of the electrode plate in ultrasonic welding. exux This refers to the distance from the upper end of the outer electrode ear to the end of the electrode plate during ultrasonic welding.
7. The battery tab encapsulation method according to claim 1, characterized in that, Determining the depth of the wrapping tape for the outer tab based on the parameter information of the battery tab and the electrode sheet includes: Obtain the tape size information; Calculate the current flowing through the inner tab and the current flowing through the outer tab based on the parameter information of the battery tabs, and obtain the current ratio of the inner tab to the outer tab. Overcurrent tests were conducted on the inner tabs welded to the electrode sheet by selecting different depths of the wrapping tape for the inner tabs. The depth of the wrapping tape for the inner tabs when they melted and the corresponding depth of the wrapping tape for the outer tabs were determined based on the current ratio of the inner tabs to the outer tabs.
8. The battery tab encapsulation method according to claim 7, characterized in that, The calculation of the current flowing through the inner electrode and the current flowing through the outer electrode based on the electrode parameter information includes: The current flowing through the inner electrode is calculated based on the battery current, electrode length, distance between the inner end of the electrode and the inner tab, and distance between the inner tab and the outer tab. The current flowing through the outer electrode is calculated based on the battery current, electrode length, distance between the inner and outer electrodes, and distance between the outer electrode and the outer end of the electrode.
9. The battery tab encapsulation method according to claim 8, characterized in that, The formula for calculating the current flowing through the inner tab is: The formula for calculating the current flowing through the outer electrode is: Among them, I int I is the current flowing through the inner electrode. ext L is the current flowing through the inner electrode, L is the length of the electrode, L1 is the distance between the inner end of the electrode and the inner tab, L2 is the distance between the inner tab and the outer tab, and L3 is the distance between the outer tab and the outer end of the electrode.
10. A battery tab packaging system, characterized in that, The battery tabs include an inner tab and an outer tab, which are encapsulated on the same electrode. The system includes: The parameter information acquisition module is used to acquire the parameter information of the battery tabs to be packaged, the parameter information of the electrode sheets, and the welding parameter information. The welding position determination module is used to determine the welding position of the inner tab of the battery tab based on the parameter information of the battery tab, the parameter information of the electrode sheet, and the welding parameter information. The welding module is used to weld the inner electrode tab onto the electrode plate according to the welding position of the inner electrode tab, so that the heat dissipation between the welding position of the inner and outer electrode tabs per unit cross-section and the lower end of the ultrasonic weld is the same. The wrapping depth determination module is used to determine the depth of the wrapping tape for the outer tab based on the parameter information of the battery tab and the parameter information of the electrode sheet; The tape wrapping module is used to wrap the tape around the outer electrode tab according to the depth of the tape wrapping, so that the inner electrode tab and the outer electrode tab melt simultaneously when the battery is discharged with a large current.
11. A computer device, characterized in that, include: Memory, which stores computer programs; A processor for executing the computer program to implement the battery tab encapsulation method according to any one of claims 1 to 9.
12. A computer-readable storage medium having a computer program stored thereon, characterized in that, The computer program is executed by a processor to implement the battery tab encapsulation method according to any one of claims 1 to 9.