Ultrasonic horn and ultrasonic welding device

Abstract

The utility model discloses an ultrasonic wave welding head and ultrasonic wave welding device belong to battery technical field, and the ultrasonic wave welding head includes: welding head main part and welding tooth. The welding head main part has the welding face, and the welding tooth is located at the welding face, and the welding face is equipped with the heat dissipation groove, and the heat dissipation groove is set apart from the welding tooth. According to the ultrasonic wave welding head of the utility model, when the workpiece of multilayer foil material such as multilayer tab sheet and adapter sheet is welded by the ultrasonic wave welding head, the damage or fracture caused by the deformation of the tab in the ultrasonic wave welding process of the tab can be reduced, and the overcurrent reliability of the tab is improved, so that the service reliability of the battery is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to an ultrasonic welding head and an ultrasonic welding device. Background Technology

[0002] In related technologies, the tabs are an important component of a battery cell, playing a crucial role in overcurrent control. Typically, the multi-layer tabs of a battery cell are first connected to the adapter plate using ultrasonic welding, and then the adapter plate is connected to the top cover of the battery cell using laser welding, thereby achieving an effective connection between the tabs and the top cover.

[0003] Because the tabs have many foil layers, during the manufacturing process, the foil is subjected to high-frequency friction from the welding head during ultrasonic welding of the tabs and adapters, generating a large amount of heat. When the heat continues to accumulate and exceeds the upper limit of the foil's plasticity, the tabs deform, causing damage or breakage. Consequently, the overcurrent capacity of the power battery's tabs is weakened, ultimately affecting the battery's service reliability.

[0004] Therefore, how to reduce the risk of heat accumulation during ultrasonic welding of electrodes, which could lead to deformation of the electrodes and cause damage or breakage, is a technical problem that needs to be solved. Utility Model Content

[0005] In view of the above problems, this utility model provides an ultrasonic welding head and an ultrasonic welding device. When using the ultrasonic welding head to weld multi-layer foil workpieces such as multi-layer tabs and adapters, the heat accumulation during the ultrasonic welding process can be reduced, which can cause deformation of the tabs and damage or breakage. This is beneficial to improving the overcurrent reliability of the tabs, thereby improving the service reliability of the battery.

[0006] In a first aspect, the present invention provides an ultrasonic welding head, comprising: a welding head body having a welding surface; welding teeth protruding from the welding surface; wherein the welding surface is provided with a heat dissipation groove, the heat dissipation groove being spaced apart from the welding teeth.

[0007] In the above technical solution, by setting heat dissipation grooves on the welding surface and spacing the heat dissipation grooves from the welding teeth, the heat dissipation area of ​​the ultrasonic welding head can be increased. When welding the tabs with the ultrasonic welding head, the heat of the tabs can be transferred to the ultrasonic welding head because the ultrasonic welding head is in close contact with the tabs. The increased heat dissipation area of ​​the ultrasonic welding head helps to dissipate the heat generated on the tabs, which can reduce the accumulation of temperature on the tabs, reduce the plastic deformation of the tabs, and help to improve the deformation of the tabs and stabilize the shape of the tabs. It can reduce the risk of the tabs being deformed and damaged or broken due to heat accumulation during the ultrasonic welding process, which is conducive to improving the overcurrent reliability of the tabs, thereby improving the service reliability of the battery.

[0008] In some embodiments, the depth of the heat dissipation groove is h, and the tooth height of the welding tooth is H in the protruding direction of the welding tooth relative to the welding surface, where 0.5H≤h≤0.8H.

[0009] In the above technical solution, by setting the ratio of the depth of the heat dissipation groove to the tooth height of the welding tooth to 0.5 to 0.8, the area of ​​the heat dissipation groove can be made larger, thereby effectively increasing the heat dissipation area of ​​the ultrasonic welding head, improving the heat dissipation effect, and also making the structure of the ultrasonic welding head more stable. Furthermore, by linking the depth of the heat dissipation groove with the tooth height of the welding tooth, the higher the tooth height, the more layers of electrode tabs are welded, the more heat is generated, and the greater the depth of the heat dissipation groove, which can better match the welding conditions and better reduce the risk of electrode tab deformation caused by heat accumulation during ultrasonic welding, thus improving the overcurrent reliability of the electrode tab and improving the service reliability of the battery.

[0010] In some embodiments, the cross-section of the heat dissipation groove is circular, elliptical, or elongated, and the cross-section obtained by cutting the heat dissipation groove with a plane parallel to the welding surface is the cross-section of the heat dissipation groove.

[0011] In the above technical solutions, by setting the heat dissipation groove to a circle, the internal stress of the ultrasonic welding head can be evenly distributed, without affecting the performance and lifespan of the ultrasonic welding head; or, by setting the heat dissipation groove to an ellipse or a long strip, the shape design of the heat dissipation groove can be more flexible, which is conducive to making full use of the area on the welding surface where no welding teeth are set.

[0012] In some embodiments, the heat dissipation groove is spherical.

[0013] In the above technical solution, by setting the heat dissipation groove to a spherical crown shape, this shape can better disperse the stress caused by the vibration of the ultrasonic welding head during welding, which can effectively extend the service life of the ultrasonic welding head. In addition, the inner wall of the spherical crown-shaped heat dissipation groove is smoother, which can avoid the electrode surface from bearing cutting force when in contact with the electrode tab, further reducing the risk of electrode tab cracking during welding.

[0014] In some embodiments, the opening edge of the heat dissipation groove is chamfered.

[0015] In the above technical solution, by forming a chamfered edge on the opening edge of the heat dissipation groove, the cutting stress on the electrode tab during welding can be avoided, which would cause the electrode tab to crack.

[0016] In some embodiments, the inner wall surface of the heat dissipation groove is provided with a heat dissipation coating.

[0017] In the above technical solution, the heat dissipation effect can be further improved by setting a heat dissipation coating on the inner wall surface of the heat dissipation groove.

[0018] In some embodiments, the inner wall of the heat dissipation groove is provided with an auxiliary groove.

[0019] In the above technical solution, by setting an auxiliary groove on the inner wall of the heat dissipation groove, the heat dissipation area of ​​the ultrasonic welding head can be further increased.

[0020] In some embodiments, the ratio of the depth of the auxiliary groove to the depth of the heat dissipation groove is 20% to 40%.

[0021] In the above technical solution, by setting the depth of the auxiliary groove to be 20% to 40% of the depth of the heat dissipation groove, the heat dissipation area can be further increased and the structure of the ultrasonic welding head can be made more stable.

[0022] In some embodiments, the distance between the heat dissipation groove and the welding tooth is 0.5mm to 1mm.

[0023] In the above technical solution, by setting the distance between the heat dissipation groove and the welding teeth to 0.5mm to 1mm, the area of ​​the welding surface without welding teeth can be fully utilized to set more and larger heat dissipation grooves. It can also avoid the large extrusion pressure on the electrode tab during ultrasonic welding due to the small distance between the heat dissipation groove and the welding teeth, thereby better reducing the risk of damage or breakage of the electrode tab during welding.

[0024] In some embodiments, the welding surface includes a welding tooth area and a pressing edge area, the pressing edge area surrounds the outer periphery of the welding tooth area, the pressing edge area is provided with the heat dissipation groove, and the welding tooth is provided in the welding tooth area.

[0025] In the above technical solution, by setting a heat dissipation groove in the pressing area of ​​the welding surface, the area space of the pressing area can be fully utilized, reducing or avoiding the impact of the heat dissipation groove on the welding tooth layout. Moreover, the processing difficulty of forming the heat dissipation groove by pressing the edge is relatively low. In addition, the pressing area is more prone to cracking of the corresponding tab part due to heat concentration than the welding area. By setting a heat dissipation groove in the pressing area, the heat dissipation area of ​​the ultrasonic welding head in the pressing area can be increased, effectively reducing the temperature accumulation of the corresponding tab part in the pressing area. For example, the temperature of the pressing area of ​​the welding head can be controlled below the plastic deformation melting point of the foil, which can improve the plastic deformation of the tab in the pressing area, stabilize the tab shape, and reduce the risk of deformation of the corresponding tab part in the pressing area due to heat accumulation during the ultrasonic welding process, resulting in damage or breakage. Furthermore, the heat dissipation groove in the pressing area can also increase the contact area between the pressing area and the tab, reduce the stress concentration of the tab in the pressing area, and improve the overcurrent reliability of the tab, thereby improving the service reliability of the battery.

[0026] In some embodiments, the distance between the heat dissipation groove in the pressing area and the outer edge of the pressing area is in the range of 0.5mm to 1.5mm.

[0027] In the above technical solution, by making the distance between the heat dissipation groove in the pressing area and the outer edge of the pressing area range from 0.5mm to 1.5mm, the area space of the pressing area can be fully utilized, more and larger heat dissipation grooves can be set as much as possible, and the processing difficulty of the heat dissipation grooves can be reduced.

[0028] In some embodiments, the pressing edge area is provided with a plurality of heat dissipation grooves, and the plurality of heat dissipation grooves provided in the pressing edge area are arranged at intervals along the circumference of the pressing edge area.

[0029] In the above technical solution, by setting multiple heat dissipation grooves at intervals along the circumference of the pressing area, the heat dissipation area of ​​the pressing area can be effectively increased, and the space in the circumferential direction of the pressing area can be fully utilized.

[0030] In some embodiments, the welding surface is rectangular, and a plurality of heat dissipation grooves provided in the pressing edge area are distributed on both sides of the length direction of the welding tooth area and / or a plurality of heat dissipation grooves provided in the pressing edge area are distributed on both sides of the width direction of the welding tooth area.

[0031] In the above technical solution, by setting multiple heat dissipation grooves on both sides of the welding area along its length and / or on both sides of the welding area along its width, the space on both sides of the welding area along its length and / or on both sides of its width can be fully utilized.

[0032] In some embodiments, the spacing between two adjacent heat dissipation grooves is 0.5 mm to 1 mm.

[0033] In the above technical solution, by setting the distance between two adjacent heat dissipation grooves to 0.5mm to 1mm, the area space of the pressing area can be fully utilized to set more and larger heat dissipation grooves, and the processing difficulty of the heat dissipation grooves can be reduced, and the pressing area can have a better pressing and fixing effect on the electrode tab.

[0034] Secondly, the present invention provides an ultrasonic welding apparatus, comprising: an ultrasonic welding head according to the first aspect embodiment of the present invention described above.

[0035] In the above technical solution, by setting the ultrasonic welding head, when welding multi-layer foil workpieces such as multi-layer tabs and adapters using the ultrasonic welding head, the heat accumulation during the ultrasonic welding process of the tabs can be reduced, which can cause deformation of the tabs and damage or breakage. This is beneficial to improving the overcurrent reliability of the tabs, thereby improving the service reliability of the battery.

[0036] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0037] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0038] Figure 1 This is a schematic diagram of an ultrasonic welding head according to some embodiments of the present invention;

[0039] Figure 2 This is a schematic diagram of a partial structure of an ultrasonic welding head according to some embodiments of the present invention;

[0040] Figure 3 yes Figure 2 Side view of the ultrasonic welding head in the image;

[0041] Figure 4 yes Figure 3 Enlarged view of point A in the middle;

[0042] Figure 5 This is a schematic diagram of a partial structure of an ultrasonic welding head according to some embodiments of the present invention;

[0043] Figure 6 yes Figure 5 Enlarged view of point B in the middle;

[0044] Figure 7This is a schematic diagram of a partial structure of an ultrasonic welding head according to some embodiments of the present invention;

[0045] Figure 8 yes Figure 7 Enlarged view of point C in the middle;

[0046] Figure 9 This is a schematic diagram of a partial structure of an ultrasonic welding head according to some embodiments of the present invention;

[0047] Figure 10 It is along Figure 9 Cross-sectional view of the FF line;

[0048] Figure 11 This is a schematic diagram of a partial structure of an ultrasonic welding head according to some embodiments of the present invention;

[0049] Figure 12 This is a schematic diagram of welding electrode tabs using an ultrasonic welding head according to some embodiments of this utility model.

[0050] Figure label:

[0051] 100. Ultrasonic welding head;

[0052] 10. Welding head body; 11. Welding surface; 111. Welding area; 112. Edge clamping area; 12. Outer edge; 13. Edge clamping chamfer;

[0053] 20. Heat dissipation groove; 21. Chamfered edge; 22. Auxiliary groove;

[0054] 30. Welded teeth;

[0055] 40. Electrode assembly; 41. Tab. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0057] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this invention are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or accompanying drawings of this invention are used to distinguish different objects, not to describe a specific order or hierarchy.

[0058] In this invention, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments.

[0059] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "attachment," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0060] In this invention, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this invention, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0061] In the embodiments of this utility model, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this utility model shown in the drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this utility model.

[0062] In this utility model, "multiple" refers to two or more.

[0063] In the embodiments of this utility model, unless otherwise specified, all embodiments and optional embodiments of this utility model can be combined with each other to form new technical solutions.

[0064] In the embodiments of this utility model, unless otherwise specified, all technical features and optional technical features of this utility model can be combined with each other to form new technical solutions.

[0065] Currently, judging from market trends, battery applications are becoming increasingly widespread. Batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in aerospace and other fields. With the continuous expansion of the application areas of power batteries, the market demand is also constantly increasing.

[0066] In related technologies, the tabs are an important component of a battery cell, playing a crucial role in overcurrent control. Typically, the multi-layer tabs of a battery cell are first connected to the adapter plate using ultrasonic welding, and then the adapter plate is connected to the top cover of the battery cell using laser welding, thereby achieving an effective connection between the tabs and the top cover.

[0067] Because the tabs have many foil layers, during the manufacturing process, the foil is subjected to high-frequency friction from the welding head during ultrasonic welding of the tabs and adapters, generating a large amount of heat. When the heat continues to accumulate and exceeds the upper limit of the foil's plasticity, the tabs deform, causing damage or breakage. Consequently, the overcurrent capacity of the power battery's tabs is weakened, ultimately affecting the battery's service reliability.

[0068] Therefore, how to reduce the risk of heat accumulation during ultrasonic welding of electrodes, which could lead to deformation of the electrodes and cause damage or breakage, is a technical problem that needs to be solved.

[0069] Based on this, the present invention proposes an ultrasonic welding head, comprising: a welding head body and welding teeth, wherein the welding head body has a welding surface and the welding teeth are disposed on the welding surface; wherein, the welding surface is provided with a heat dissipation groove, and the heat dissipation groove is disposed at a distance from the welding teeth.

[0070] In the above technical solution, by setting heat dissipation grooves on the welding surface and spacing the heat dissipation grooves from the welding teeth, the heat dissipation area of ​​the ultrasonic welding head can be increased. When welding the tabs with the ultrasonic welding head, the heat of the tabs can be transferred to the ultrasonic welding head because the ultrasonic welding head is in close contact with the tabs. The increased heat dissipation area of ​​the ultrasonic welding head helps to dissipate the heat generated on the tabs, which can reduce the accumulation of temperature on the tabs, reduce the plastic deformation of the tabs, and help to improve the deformation of the tabs and stabilize the shape of the tabs. It can reduce the risk of the tabs being deformed and damaged or broken due to heat accumulation during the ultrasonic welding process, which is conducive to improving the overcurrent reliability of the tabs, thereby improving the service reliability of the battery.

[0071] The following is for reference. Figures 1-12 Description of an ultrasonic welding head 100 according to an embodiment of the present utility model.

[0072] refer to Figures 1-4 In the first aspect, the present invention provides an ultrasonic welding head 100, comprising: a welding head body 10 and welding teeth 30, the welding head body 10 having a welding surface 11, and the welding teeth 30 protruding from the welding surface 11; wherein, the welding surface 11 is provided with a heat dissipation groove 20, and the heat dissipation groove 20 and the welding teeth 30 are spaced apart.

[0073] The ultrasonic welding head 100 is the part of the ultrasonic welding device that comes into contact with the multi-layer foil during the welding process. The high-frequency vibration energy generated by the transducer is usually transmitted to the ultrasonic welding head 100 after the amplitude is adjusted by the amplitude transformer. The ultrasonic welding head 100 then concentrates the received vibration energy onto the joint of the multi-layer foil. Under pressure, the energy is converted into heat energy through friction, which softens and welds the parts together.

[0074] The welding head body 10 has a welding surface 11, which can be a plane in contact with the multilayer foil. For example, the welding head body 10 can be made of materials with good thermal conductivity and corrosion resistance, such as aluminum alloy, titanium alloy, or stainless steel.

[0075] The welding tooth 30 protrudes from the welding surface 11, meaning that the welding tooth 30 is located on the welding surface 11 and protrudes relative to the welding surface 11. The welding tooth 30 can be spherical or frustum-shaped.

[0076] The welding surface 11 is provided with a heat dissipation groove 20. The location of the heat dissipation groove 20 on the welding surface 11 can increase the heat dissipation area of ​​the welding surface 11.

[0077] The welding surface 11 may be provided with one or more heat dissipation grooves 20, which are spaced apart from the welding teeth 30 to reduce or avoid the influence of the heat dissipation grooves 20 on the welding teeth 30.

[0078] In the above technical solution, by providing a heat dissipation groove 20 on the welding surface 11 and spacing the heat dissipation groove 20 from the welding teeth 30, the heat dissipation area of ​​the ultrasonic welding head 100 can be increased. When welding the tab 41 using the ultrasonic welding head 100, the heat of the tab 41 can be transferred to the ultrasonic welding head 100 because the ultrasonic welding head 100 is in close contact with the tab 41. The increased heat dissipation area of ​​the ultrasonic welding head 100 helps to dissipate the heat generated on the tab 41, reduces the temperature accumulation of the tab 41, reduces the plastic deformation of the tab 41, helps to improve the deformation of the tab 41, stabilizes the shape of the tab 41, reduces the risk of the tab 41 deforming due to heat accumulation during the ultrasonic welding process, and helps to improve the overcurrent reliability of the tab 41, thereby improving the service reliability of the battery.

[0079] In some embodiments, refer to Figure 3 and Figure 4The depth of the heat dissipation groove 20 is h, and the tooth height of the welding tooth 30 in the protruding direction relative to the welding surface 11 is H, where 0.5H≤h≤0.8H.

[0080] The protruding direction of the welding tooth 30 relative to the welding surface 11 can be referenced. Figure 3 and Figure 4 In the e3 direction.

[0081] The depth h of the heat dissipation groove 20 refers to the maximum distance between the welding surface 11 and the inner wall of the heat dissipation groove 20 in the direction perpendicular to the welding surface 11.

[0082] The depth h of the heat dissipation groove 20 can be 0.5H, 0.55H, 0.6H, 0.65H, 0.7H, 0.75H, 0.8H, etc.

[0083] In the above technical solution, by setting the ratio of the depth of the heat dissipation groove 20 to the tooth height of the welding tooth 30 to 0.5 to 0.8, the area of ​​the heat dissipation groove 20 can be made larger, thereby effectively increasing the heat dissipation area of ​​the ultrasonic welding head 100, improving the heat dissipation effect, and also making the structure of the ultrasonic welding head 100 more stable. Furthermore, by designing the depth of the heat dissipation groove 20 in relation to the tooth height of the welding tooth 30, the higher the tooth height of the welding tooth 30, the more layers of the electrode tab 41 are welded, the more heat is generated, and the greater the depth of the heat dissipation groove 20 is, the better it can match the welding conditions, and better reduce the risk of deformation of the electrode tab 41 caused by heat accumulation during the ultrasonic welding process, which may lead to damage or breakage. This is beneficial to improving the overcurrent reliability of the electrode tab 41, thereby improving the service reliability of the battery.

[0084] In some embodiments, the cross-section of the heat dissipation groove 20 is circular, elliptical, or elongated, and the cross-section obtained by cutting the heat dissipation groove 20 with a plane parallel to the welding surface 11 is the cross-section of the heat dissipation groove 20.

[0085] In the above technical solutions, by setting the heat dissipation groove 20 to a circle, the internal stress of the ultrasonic welding head 100 can be evenly distributed, without affecting the performance and lifespan of the ultrasonic welding head 100; or, by setting the heat dissipation groove 20 to an ellipse or a long strip, the shape design of the heat dissipation groove 20 can be more flexible, which is conducive to making full use of the area on the welding surface 11 where the welding teeth 30 are not set.

[0086] In some embodiments, the heat dissipation groove 20 is spherical.

[0087] In the above technical solution, by setting the heat dissipation groove 20 to a spherical shape, this shape can better disperse the stress caused by the vibration of the ultrasonic welding head 100 during welding, which can effectively extend the service life of the ultrasonic welding head 100. In addition, the inner wall of the spherical heat dissipation groove 20 is smoother, which can prevent the surface of the electrode 41 from bearing cutting force when it comes into contact with the electrode tab 41, further reducing the risk of the electrode tab 41 cracking during the welding process.

[0088] In some embodiments, refer to Figure 5 and Figure 6 The opening edge of the heat dissipation groove 20 is formed with a chamfered portion 21.

[0089] The chamfered portion 21 can be an arc-shaped chamfered portion 21.

[0090] In the above technical solution, by forming a chamfered portion 21 on the opening edge of the heat dissipation groove 20, the cutting stress on the electrode tab 41 during welding can be avoided, which would cause the electrode tab 41 to crack.

[0091] In some embodiments, the inner wall surface of the heat dissipation groove 20 is provided with a heat dissipation coating.

[0092] For example, the heat dissipation coating provided on the inner wall surface of the heat dissipation groove 20 can be a graphene coating, an aluminum layer, a copper layer, etc.

[0093] In the above technical solution, the heat dissipation effect can be further improved by setting a heat dissipation coating on the inner wall surface of the heat dissipation groove 20.

[0094] In some embodiments, refer to Figure 7 and Figure 8 The inner wall of the heat dissipation groove 20 is provided with an auxiliary groove 22.

[0095] For example, one or more auxiliary grooves 22 can be provided on the inner wall of the heat dissipation groove 20. When multiple auxiliary grooves 22 are provided in a single heat dissipation groove 20, the multiple auxiliary grooves 22 provided on the inner wall of a single heat dissipation groove 20 can be evenly distributed.

[0096] In the above technical solution, by providing an auxiliary groove 22 on the inner wall of the heat dissipation groove 20, the heat dissipation area of ​​the ultrasonic welding head 100 can be further increased.

[0097] In some embodiments, the ratio of the depth of the auxiliary groove 22 to the depth of the heat dissipation groove 20 is 20% to 40%.

[0098] For example, the ratio of the depth of the auxiliary groove 22 to the depth of the heat dissipation groove 20 is 20%, 25%, 30%, 35%, 40%, etc.

[0099] When an auxiliary groove 22 is provided on the inner wall of the heat dissipation groove 20, the portion of the inner wall surface of the heat dissipation groove 20 without the auxiliary groove 22 is the main groove wall surface. The depth of the heat dissipation groove 20 refers to the maximum distance between the welding surface 11 and the main groove wall surface in the direction perpendicular to the welding surface 11.

[0100] The depth of the auxiliary groove 22 refers to the distance from the opening of the auxiliary groove 22 to the deepest point of the recess in the auxiliary groove 22.

[0101] In the above technical solution, by making the depth ratio of the auxiliary groove 22 to the depth of the heat dissipation groove 20 20% to 40%, the auxiliary groove 22 can be set to further increase the heat dissipation area and make the structure of the ultrasonic welding head 100 more stable.

[0102] In some embodiments, refer to Figure 2 The distance between the heat dissipation groove 20 and the welding tooth 30 is 0.5mm to 1mm.

[0103] For example, refer to Figure 2 The distance between the heat dissipation groove 20 and the welding tooth 30 is L1, and the range of L1 is 0.5mm to 1mm. For example, the distance L1 between the heat dissipation groove 20 and the welding tooth 30 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, etc.

[0104] In the above technical solution, by setting the distance between the heat dissipation groove 20 and the welding tooth 30 to 0.5mm to 1mm, the area of ​​the welding surface 11 without welding tooth 30 can be fully utilized to set more and larger heat dissipation grooves 20. It can also avoid the large squeezing force on the electrode tab 41 during the ultrasonic welding process due to the small distance between the heat dissipation groove 20 and the welding tooth 30, thereby better reducing the risk of damage or breakage of the electrode tab 41 during the welding process.

[0105] In some embodiments, refer to Figures 2-9 The welding surface 11 includes a welding tooth area 111 and a pressing edge area 112. The pressing edge area 112 surrounds the outer periphery of the welding tooth area 111. The pressing edge area 112 is provided with a heat dissipation groove 20, and the welding tooth 30 is provided in the welding tooth area 111.

[0106] By providing a heat dissipation groove 20 in the pressing area 112 of the welding surface 11, the pressing area 112 is divided into a part with a heat dissipation groove 20 and a part without a heat dissipation groove 20. The part with a heat dissipation groove 20 can mainly bear the heat dissipation function of the pressing area 112, and at the same time, it can also reduce the stress concentration of the electrode tab 41 here. The part without a heat dissipation groove 20 in the pressing area 112 can mainly fix the electrode tab 41, thereby achieving effective welding of the electrode tab 41.

[0107] For example, the welding surface 11 can be rectangular, the welding tooth area 111 can be rectangular, and the pressing area 112 can be a rectangular ring.

[0108] In the above technical solution, by setting a heat dissipation groove 20 in the pressing area 112 of the welding surface 11, the area space of the pressing area 112 can be fully utilized, reducing or avoiding the impact of the heat dissipation groove 20 on the layout of the welding teeth 30. Furthermore, the processing difficulty of forming the heat dissipation groove 20 by pressing the edge is relatively low. In addition, the pressing area 112 is more prone to cracking of the electrode tab 41 part corresponding to the pressing area 112 due to heat concentration compared to the welding area 111. By setting a heat dissipation groove 20 in the pressing area 112, the heat dissipation area of ​​the ultrasonic welding head 100 in the pressing area 112 can be increased, effectively reducing the electrode tab corresponding to the pressing area 112. The temperature accumulation in part 41 can, for example, keep the temperature of the pressing area 112 of the welding head below the melting point of the foil plastic deformation. This can improve the plastic deformation of the tab 41 in the pressing area 112, stabilize the shape of the tab 41, and reduce the risk of damage or breakage caused by heat accumulation during the ultrasonic welding process of the tab 41 and deformation of the corresponding part of the tab 41 in the pressing area 112. In addition, the heat dissipation groove 20 provided in the pressing area 112 can also increase the contact area between the pressing area 112 and the tab 41, reduce the stress concentration of the tab 41 in the pressing area 112, and improve the overcurrent reliability of the tab 41, thereby improving the service reliability of the battery.

[0109] In some embodiments, refer to Figure 2 The distance between the heat dissipation groove 20 located in the pressure edge area 112 and the outer edge 12 of the pressure edge area 112 is 0.5mm to 1.5mm.

[0110] The outer edge 12 of the pressing area 112 refers to the edge of the pressing area 112 that is far away from the welding area 111.

[0111] For example, refer to Figures 2-9 The distance between the heat dissipation groove 20 in the pressing edge area 112 and the outer edge 12 of the pressing edge area 112 is L2, and the range of L2 is 0.5mm to 1.5mm. For example, the distance L2 between the heat dissipation groove 20 in the pressing edge area 112 and the outer edge 12 of the pressing edge area 112 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, etc.

[0112] For example, when the outer edge 12 of the pressing area 112 is not chamfered, the distance between the heat dissipation groove 20 and the outer edge 12 of the pressing area 112 can be 0 to 0.5 mm. For example, when the outer edge 12 of the pressing area 112 is chamfered, the distance between the heat dissipation groove 20 and the outer edge 12 of the pressing area 112 can be 1 mm to 1.5 mm. The chamfer on the outer edge 12 of the pressing area 112 can be a pressing chamfer 13, and the width of the pressing chamfer 13 is approximately 1 mm.

[0113] In the above technical solution, by making the distance between the heat dissipation groove 20 provided in the pressing area 112 and the outer edge 12 of the pressing area 112 range from 0.5mm to 1.5mm, the area space of the pressing area 112 can be fully utilized, and more and larger heat dissipation grooves 20 can be provided as much as possible, and the processing difficulty of the heat dissipation grooves 20 can be reduced.

[0114] In some embodiments, refer to Figures 2-9 The pressing area 112 is provided with a plurality of heat dissipation grooves 20, which are arranged at intervals along the circumference of the pressing area 112.

[0115] For example, the multiple heat dissipation grooves 20 provided in the pressure edge area 112 can be distributed at equal intervals.

[0116] In the above technical solution, by providing multiple heat dissipation grooves 20 spaced circumferentially along the pressing edge area 112, the heat dissipation area of ​​the pressing edge area 112 can be effectively increased, and the space in the circumferential direction of the pressing edge area can be fully utilized.

[0117] In some embodiments, refer to Figures 2-9 The welding surface 11 is rectangular, and multiple heat dissipation grooves 20 provided in the pressing edge area 112 are distributed on both sides of the length direction of the welding tooth area 111 and / or multiple heat dissipation grooves 20 provided in the pressing edge area 112 are distributed on both sides of the width direction of the welding tooth area 111.

[0118] For example, the length direction of the welding surface 11 can be referred to as the e1 direction in the attached figure, and the width direction of the welding surface 11 can be referred to as the e2 direction in the attached figure.

[0119] The length direction of the welding area 111 is consistent with the length direction of the welding surface 11, and the width direction of the welding area 111 is consistent with the width direction of the welding surface 11.

[0120] For example, refer to Figure 2 Multiple heat dissipation grooves 20, located in the pressure edge area 112, are distributed on both sides of the weld tooth area 111 along its length. For example, refer to... Figure 9Multiple heat dissipation grooves 20, located in the pressure edge area 112, are distributed on both sides of the welding tooth area 111 in the width direction. For example, refer to... Figure 11 Multiple heat dissipation grooves 20 provided in the pressing edge area 112 are distributed on both sides of the length direction of the welding tooth area 111 and multiple heat dissipation grooves 20 provided in the pressing edge area 112 are distributed on both sides of the width direction of the welding tooth area 111.

[0121] In the above technical solution, by arranging multiple heat dissipation grooves 20 on both sides of the length direction and / or both sides of the width direction of the welding area 111, the space on both sides of the length direction and / or both sides of the width direction of the welding area 111 can be fully utilized.

[0122] In some embodiments, refer to Figures 2-9 The distance between two adjacent heat dissipation grooves 20 is 0.5mm to 1mm.

[0123] For example, refer to Figures 2-9 The distance between two adjacent heat dissipation grooves 20 is d, and the value of d ranges from 0.5mm to 1mm. For example, the distance d between two adjacent heat dissipation grooves 20 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, etc.

[0124] In the above technical solution, by setting the distance between two adjacent heat dissipation grooves 20 to 0.5mm to 1mm, the area space of the pressing area 112 can be fully utilized to set more and larger heat dissipation grooves 20, and the processing difficulty of the heat dissipation grooves 20 can be reduced, and the pressing area 112 can have a better pressing and fixing effect on the tab 41.

[0125] In a second aspect, the present invention provides an ultrasonic welding apparatus, comprising: an ultrasonic welding head 100 according to the first aspect embodiment of the present invention described above.

[0126] In the above technical solution, by setting the ultrasonic welding head 100, when using the ultrasonic welding head 100 to weld multi-layer tab 41 pieces and adapter pieces and other multi-layer foil workpieces, the heat accumulation during the ultrasonic welding process of tab 41 can be reduced, which can cause deformation of tab 41 and damage or breakage. This is beneficial to improving the overcurrent reliability of tab 41, thereby improving the service reliability of the battery.

[0127] The following reference Figures 2-4 Description of an ultrasonic welding head 100 according to some embodiments of the present invention.

[0128] Reference Figures 2-4In this embodiment, the ultrasonic welding head 100 includes a welding head body 10 and welding teeth 30. The welding head body 10 has a welding surface 11, which includes a welding tooth area 111 and a pressing area 112. The pressing area 112 surrounds the outer periphery of the welding tooth area 111 and is provided with a heat dissipation groove 20. The welding teeth 30 are disposed in the welding tooth area 111. Both the welding surface 11 and the welding tooth area 111 are rectangular, while the pressing area 112 is a rectangular annular shape. The outer edge 12 of the pressing area 112 is provided with a chamfer, which can be arc-shaped.

[0129] There are multiple heat dissipation grooves 20, which are distributed on both sides of the length direction of the welding tooth area 111. The cross-section of the heat dissipation groove 20 is circular, and the heat dissipation groove 20 is spherical.

[0130] The following example uses this embodiment to calculate the increased heat dissipation area achieved by providing a heat dissipation groove 20 in the pressure zone 112.

[0131] The opening of the heat dissipation groove 20 is circular with a diameter of D and a radius of r = D / 2. The depth of the heat dissipation groove 20 is h, and the radius of the sphere in the heat dissipation groove 20 is R. The area of ​​the welding surface 11 occupied by a single heat dissipation groove 20 is S1 = πr. 2 The inner surface area of ​​a single heat dissipation groove 20 is S2=2πRh, then from the geometric relationship of the spherical cap, we can know that r 2 =h, from which we can derive R = / , S2 = π*, and the increased heat dissipation area due to setting a single heat dissipation groove 20 is ΔS = S2 - S1 = πh 2 .

[0132] When the number of heat dissipation grooves 20 is N, the increased heat dissipation area of ​​the ultrasonic welding head 100 is ΔSx = N * ΔS = N * πh 2 .

[0133] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0134] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An ultrasonic welding head, characterized in that, include: A welding head body, wherein the welding head body has a welding surface; Welding teeth, which protrude from the welding surface; The welding surface is provided with a heat dissipation groove, which is spaced apart from the welding teeth.

2. The ultrasonic welding head according to claim 1, characterized in that, The depth of the heat dissipation groove is h, and the tooth height of the welding tooth is H in the protruding direction of the welding tooth relative to the welding surface, where 0.5H≤h≤0.8H.

3. The ultrasonic welding head according to claim 1, characterized in that, The cross-section of the heat dissipation groove is circular, elliptical, or elongated. The cross-section obtained by cutting the heat dissipation groove with a plane parallel to the welding surface is the cross-section of the heat dissipation groove.

4. The ultrasonic welding head according to claim 1, characterized in that, The heat dissipation groove is spherical.

5. The ultrasonic welding head according to claim 1, characterized in that, The opening edge of the heat dissipation groove has a chamfered portion.

6. The ultrasonic welding head according to claim 1, characterized in that, The inner wall of the heat dissipation groove is provided with a heat dissipation coating.

7. The ultrasonic welding head according to claim 1, characterized in that, The inner wall of the heat dissipation groove is provided with an auxiliary groove.

8. The ultrasonic welding head according to claim 7, characterized in that, The ratio of the depth of the auxiliary groove to the depth of the heat dissipation groove is 20% to 40%.

9. The ultrasonic welding head according to claim 1, characterized in that, The distance between the heat dissipation groove and the welding tooth is 0.5mm to 1mm.

10. The ultrasonic welding head according to any one of claims 1-9, characterized in that, The welding surface includes a welding tooth area and a pressing edge area. The pressing edge area surrounds the outer periphery of the welding tooth area and is provided with the heat dissipation groove. The welding tooth is located in the welding tooth area.

11. The ultrasonic welding head according to claim 10, characterized in that, The distance between the heat dissipation groove in the pressing area and the outer edge of the pressing area is in the range of 0.5mm to 1.5mm.

12. The ultrasonic welding head according to claim 10, characterized in that, The pressing edge area is provided with a plurality of heat dissipation grooves, which are arranged at intervals along the circumference of the pressing edge area.

13. The ultrasonic welding head according to claim 12, characterized in that, The welding surface is rectangular, and a plurality of heat dissipation grooves provided in the pressing edge area are distributed on both sides of the length direction of the welding tooth area and / or a plurality of heat dissipation grooves provided in the pressing edge area are distributed on both sides of the width direction of the welding tooth area.

14. The ultrasonic welding head according to claim 12, characterized in that, The distance between two adjacent heat dissipation grooves is 0.5mm to 1mm.

15. An ultrasonic welding apparatus, characterized in that, include: The ultrasonic welding head according to any one of claims 1-14.

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