Patent Application
20240275004
This application claims priority under 35 U.S.C. § 119(a) to Chinese Patent Application No. 202310091082.4, filed Feb. 9, 2023, the entire disclosure of which is incorporated herein by reference.
This disclosure relates to the electronics field, and in particular to an end cover assembly, an energy-storage apparatus, and an electricity-consumption device.
For energy-storage apparatuses such as lithium batteries or sodium batteries, after end cover assemblies are assembled, electrolytes are filled through liquid-injection holes of the end cover assemblies, and after filling the electrolytes, sealing caps are welded to the liquid-injection hole to seal the liquid-injection hole. However, for the existing energy-storage apparatuses, poor welding often occurs after welding the sealing cap, resulting in low product yield.
In a first aspect of the present disclosure, an end cover assembly for an energy-storage apparatus is provided. The end cover assembly includes a top cover, a sealing cap, and an annular welding portion. The top cover has a first surface and further defines a liquid-injection hole extending through the first surface. The first surface includes a first sub-surface and a second sub-surface connected to the first sub-surface, the first sub-surface is around the liquid-injection hole, the second sub-surface is around a periphery of the first sub-surface, and roughness of the first sub-surface is greater than roughness of the second sub-surface. The sealing cap seals the liquid-injection hole and is connected to the top cover. The annular welding portion is located at a junction between the sealing cap and the top cover. The top cover is further provided with a first welding mark at the first sub-surface. The first welding mark includes a first end portion and a second end portion opposite to the first end portion, the first end portion is connected to the welding portion, and the second end portion is located at a periphery of the welding portion and is spaced apart from the welding portion. The top cover is further provided with a second welding mark at the first sub-surface. The second welding mark includes a third end portion and a fourth end portion opposite to the third end portion, the third end portion is connected to the welding portion, and the fourth end portion is located at the periphery of the welding portion and is spaced apart from the welding portion.
In a second aspect of the present disclosure, an energy-storage apparatus is provided. The energy-storage apparatus includes an end cover assembly, an adapter sheet, and an electrode assembly. The end cover assembly includes a top cover, a sealing cap, and an annular welding portion. The top cover has a first surface and further defines a liquid-injection hole extending through the first surface. The first surface includes a first sub-surface and a second sub-surface connected to the first sub-surface, the first sub-surface is around the liquid-injection hole, the second sub-surface is around a periphery of the first sub-surface, and roughness of the first sub-surface is greater than roughness of the second sub-surface. The sealing cap seals the liquid-injection hole and is connected to the top cover. The annular welding portion is located at a junction between the sealing cap and the top cover. The top cover is further provided with a first welding mark at the first sub-surface. The first welding mark includes a first end portion and a second end portion opposite to the first end portion, the first end portion is connected to the welding portion, and the second end portion is located at a periphery of the welding portion and is spaced apart from the welding portion. The top cover is further provided with a second welding mark at the first sub-surface. The second welding mark includes a third end portion and a fourth end portion opposite to the third end portion, the third end portion is connected to the welding portion, and the fourth end portion is located at the periphery of the welding portion and is spaced apart from the welding portion. The adapter sheet is disposed at a side of the top cover away from the first surface and has one end electrically connected to the end cover assembly. The electrode assembly is disposed at a side of the adapter sheet away from the end cover assembly. The electrode assembly is electrically connected to one end of the adapter sheet away from the end cover assembly.
In a third aspect of the present disclosure, an electricity-consumption device is provided. The electricity-consumption device includes an electricity-consumption device body and an energy-storage apparatus. The energy-storage apparatus supplies power to the electricity-consumption device body. The energy-storage apparatus includes an end cover assembly, an adapter sheet, and an electrode assembly. The end cover assembly includes a top cover, a sealing cap, and an annular welding portion. The top cover has a first surface and further defines a liquid-injection hole extending through the first surface. The first surface includes a first sub-surface and a second sub-surface connected to the first sub-surface, the first sub-surface is around the liquid-injection hole, the second sub-surface is around a periphery of the first sub-surface, and roughness of the first sub-surface is greater than roughness of the second sub-surface. The sealing cap seals the liquid-injection hole and is connected to the top cover. The annular welding portion is located at a junction between the sealing cap and the top cover. The top cover is further provided with a first welding mark at the first sub-surface. The first welding mark includes a first end portion and a second end portion opposite to the first end portion, the first end portion is connected to the welding portion, and the second end portion is located at a periphery of the welding portion and is spaced apart from the welding portion. The top cover is further provided with a second welding mark at the first sub-surface. The second welding mark includes a third end portion and a fourth end portion opposite to the third end portion, the third end portion is connected to the welding portion, and the fourth end portion is located at the periphery of the welding portion and is spaced apart from the welding portion. The adapter sheet is disposed at a side of the top cover away from the first surface and has one end electrically connected to the end cover assembly. The electrode assembly is disposed at a side of the adapter sheet away from the end cover assembly. The electrode assembly is electrically connected to one end of the adapter sheet away from the end cover assembly
To describe technical solutions in the present disclosure more clearly, the following briefly introduces the accompanying drawings for describing implementations. The accompanying drawings in the following description show merely some implementations of the present disclosure, and a person of ordinary skill in the art may derive other drawings from these accompanying drawings.
300—electricity-consumption device, 310—electricity-consumption device body, 200—energy-storage apparatus, 210—electrode assembly, 211—positive-electrode tab, 213—negative-electrode tab, 230—adapter sheet, 231—positive-electrode adapter sheet, 233—negative-electrode adapter sheet, 250—housing, 100—end cover assembly, 10—top cover, 11—first surface, 111—first sub-surface, 113—second sub-surface, 115—abutting sub-surface, 12—liquid-injection hole, 13—second surface, 131—third sub-surface, 133—fourth sub-surface, 135—fifth sub-surface, 14—protrusion, 15—groove, 16—first accommodating recess, 17—second accommodating recess, 18—first through hole, 19—explosion-proof hole, 21—explosion-proof sheet, 23—protective sheet, 30—sealing cap, 31—welding portion, 33—first welding mark, 331—first end portion, 333—second end portion, 35—second welding mark, 351—third end portion, 353—fourth end portion, 41—positive-electrode metal pressing block, 43—negative-electrode metal pressing block, 50—lower plastic member, 51—body portion, 52—first abutting portion, 53—second abutting portion, 54—second through hole, 55—first plastic sub-member, 551—leakage hole, 552—first peripheral side wall, 553—second peripheral side wall, 554—vent channel, 56—second plastic sub-member, 57—third plastic sub-member, 58—fourth plastic sub-member, 61—positive-electrode upper plastic member, 63—negative-electrode upper plastic member, 70—pole, 71—positive pole, 73—negative pole, 80—sealing ring, 90—sealing pin.
To enable those skilled in the art to better understand the solutions of the present disclosure, the technical solutions in embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present disclosure. The described embodiments are merely some of, rather than all, the embodiments of the present disclosure. Other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present disclosure shall fall within the scope of protection of the present disclosure.
The terms such as “first” and “second” in the specification and the claims of the present application and in the accompanying drawings are intended to distinguish different objects, rather than to describe a specific order. In addition, the terms of “include” and “have” and any variations thereof are intended to cover the non-exclusive inclusion. For example, the process, method, system, product or device, which includes a series of steps or units, is not limited to the listed steps or units, but optionally further includes unlisted steps or units, or optionally further includes other steps or units inherent to the process, method, product or device.
The technical solutions in the embodiments of the present disclosure will be described below with reference to the accompanying drawings.
It should be noted that, for ease of description, in the embodiments of the present disclosure, the same reference numerals denote the same components, and for the sake of brevity, the detailed description of the same components is omitted in different embodiments.
Referring to
The electricity-consumption device 300 in the embodiments of the present disclosure may be, but not limited to, a portable electronic device, such as a mobile phone, a tablet computer, a laptop, a desktop computer, a smart bracelet, a smart watch, an e-book reader, and a game console. The electricity-consumption device 300 may also be transportation means such as an automobile, a truck, a car, a van, a bullet train, a high-speed train, and an electric bicycle. In addition, the electricity-consumption device 300 may also be various household appliances, etc. It can be understood that the electricity-consumption device 300 illustrated in the drawings of the present disclosure is only one of the forms of the electricity-consumption device 300, and should not be construed as a limitation on the electricity-consumption device 300 provided in the present disclosure.
Referring to
The energy-storage apparatus 200 of the embodiments of the present disclosure may be, but not limited to, a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium/lithium-ion battery, a sodium-ion battery or a magnesium-ion battery, an energy-storage battery, and other energy-storage apparatus 200. It can be understood that the energy-storage apparatus 200 illustrated in the drawings of the present disclosure is only one of the forms of the energy-storage apparatus 200, and should not be construed as a limitation on the energy-storage apparatus 200 provided in the present disclosure.
Optionally, the adapter sheet 230 may be, but not limited to, at least one of copper foil and aluminum foil.
Optionally, the adapter sheet 230 includes a positive-electrode adapter sheet 231 and a negative-electrode adapter sheet 233. The electrode assembly 210 includes a positive-electrode sheet (not shown), a separator (not shown) and a negative-electrode sheet (not shown) arranged in sequence. The positive-electrode sheet and the negative-electrode sheet are both electrically connected to the end cover assembly 100 by means of the adapter sheet 230. The positive-electrode sheet includes a positive current collector, a positive-electrode tab 211 electrically connected to the positive current collector, and a positive active layer disposed on a surface of the positive current collector. The positive-electrode sheet is electrically connected to the positive-electrode adapter sheet 231 by means of the positive-electrode tab 211. The negative-electrode sheet includes a negative current collector, a negative-electrode tab 213 electrically connected to the negative current collector, and a negative active layer disposed on a surface of the negative current collector. The negative-electrode sheet is electrically connected to the negative-electrode adapter sheet 233 by means of the negative-electrode tab 213.
It can be understood that the positive-electrode adapter sheet 231 and the negative-electrode adapter sheet 233 are different adapter sheets. The adapter sheet 230 for electrically connecting the positive-electrode tab 211 to the end cover assembly 100 is the positive-electrode adapter sheet 231, and the adapter sheet 230 for electrically connecting the negative-electrode tab 213 to the end cover assembly 100 is the negative-electrode adapter sheet 233.
In some embodiments, the energy-storage apparatus 200 of the present disclosure further includes a housing 250. The housing 250 is connected to the end cover assembly 100, and the housing 250 and the end cover assembly 100 cooperatively define an accommodating recess. The accommodating recess is used to accommodate the electrode assembly 210 and the adapter sheet 230.
In some embodiments, the energy-storage apparatus 200 of the present disclosure further includes an electrolyte (not shown). The electrolyte is accommodated in the accommodating recess, and at least part of the positive-electrode sheet and at least part of the negative-electrode sheet are immersed in the electrolyte.
After the components of the energy-storage apparatus are assembled, the electrolyte is filled through a liquid-injection hole of the end cover assembly. After the electrolyte is filled, the liquid-injection hole is plugged with a rubber tack, and a sealing cap made of metal is welded to a top cover by means of laser welding above the liquid-injection hole to achieve secondary sealing for the liquid-injection hole so as to prevent the electrolyte from overflowing.
The top cover is generally made of metal, such as 3-series aluminum alloy. Aluminum alloy is a non-ferrous metal that has strong reflectivity to all kinds of light. Laser, as a high-energy beam, is more likely to reflect on the surface of the aluminum alloy. In other words, aluminum alloy, a non-ferrous metal, has high reflectivity and low absorptivity for laser. In addition, all metals have thermal conductivity, so aluminum alloy also has strong thermal conductivity, and is easy to reflect laser or quickly transfer the heat of laser during laser welding, so that the temperature of the part to-be-welded cannot meet the welding requirements, eventually resulting in welding failure of the sealing cap. Thus, during laser welding of the sealing cap, it is necessary to strictly control the power density of laser and the movement speed during welding to prevent reflection or transfer of laser, and it is desired to weld aluminum alloy with extremely high energy density beam in a very short time, which can prevent the problems such as reflection.
In addition, during welding of the sealing cap, the laser absorption of the welding material depends on some important properties of the material, such as absorptivity, reflectivity, thermal conductivity, melting temperature, and evaporation temperature, in which the absorptivity is most important. The factors that affect the laser beam absorptivity of the material include two aspects. The first is the coefficient of resistance of the material. From the measurement of the absorptivity of the polished surface of the material, it has been found that the absorptivity of the material is directly proportional to the square root of the coefficient of resistance, and the coefficient of resistance varies with the temperature. Secondly, the surface state (or smoothness) of the material has an important influence on the beam absorptivity, and thus significantly influences the welding effect.
Referring to
It should be noted that when the end cover assembly 100 is mounted to the energy-storage apparatus 200, the top cover 10 is connected to the housing 250 to define the accommodating recess.
Optionally, the top cover 10 may be made of, but not limited to, aluminum or an aluminum alloy, etc. The end cover assembly 100 of the embodiments of the present disclosure includes the top cover 10. The top cover 10 has a first surface 11, and the top cover 10 further defines the liquid-injection hole 12 extending through the first surface 11. The first surface 11 includes a first sub-surface 111 and a second sub-surface 113 connected to each other, the first sub-surface 111 is around the liquid-injection hole 12, the second sub-surface 113 is around the periphery of the first sub-surface 111, and the roughness of the first sub-surface 111 is greater than the roughness of the second sub-surface 113. Since the roughness of the first sub-surface 111 is greater than the roughness of the second sub-surface 113, when the sealing cap is subsequently welded to seal the liquid-injection hole 12, the reflection of laser by the top cover 10 can be reduced, so as to reduce the laser absorptivity of the welding material of the top cover 10, avoiding the problem that the temperature cannot reach a welding temperature caused by the reduced laser absorptivity of the welding material due to the reflection of laser by the top cover 10. In addition, since the roughness of the first sub-surface 111 is greater than the roughness of the second sub-surface 113, when a top patch is attached to the first surface 11 of the top cover 10, gas between the top patch and the first sub-surface 111 of the top cover 10 can be discharged through a rough micro-gap of the first sub-surface 111 to avoid formation of local bubbles, which can increase the binding force (i.e., the adhesive force) between the top patch and the first sub-surface 111, improving the sealing effect on the liquid-injection hole 12. Furthermore, during the process of filling the electrolyte into the energy-storage apparatus 200 through the liquid-injection hole 12 at high speed, a small amount of electrolyte will splash around the liquid-injection hole 12. However, the subsequent laser welding of the sealing cap 30 requires high cleanliness of the metal surface. If there are impurities, such as the electrolyte or dust, remaining on the metal surface, when the laser beam scans to the impurities (e.g., the fine particles of electrolyte), the impurities will vaporize to explode instantly, which is likely to cause defects such as pores or splashes at the welded part.
Optionally, the first sub-surface 111 is formed by means of low-power laser scanning that removes impurities such as the electrolyte or dust remaining around the liquid-injection hole by ablation while forming the rough surface (i.e., the first sub-surface 111), so that the welding surface is cleaned in advance for the subsequent high-power laser welding process of the sealing cap 30 to improve the uniformity and sealing performance of welding, thereby prolonging the service life of the energy-storage apparatus 200.
Optionally, the sealing cap may be made of, but not limited to, aluminum or an aluminum alloy, etc.
Optionally, the roughness Ra of the first sub-surface 111 is in a range of 3.2≤Ra≤50. Specifically, the roughness Ra of the first sub-surface 111 may be, but not limited to, 3.2, 5, 8, 10, 15, 20, 25, 30, 35, 40, 45, 50, etc. If the roughness of the first sub-surface 111 is too small, the laser reflectivity of the first sub-surface 111 is excessively large, affecting the laser absorptivity of the laser welding material, so that during welding of the sealing cap to the top cover 10, the temperature cannot reach the welding temperature, affecting the sealing effect of the sealing cap on the liquid-injection hole 12. If the roughness of the first sub-surface 111 is too large, when the top patch is attached to the first surface 11, an adhesive layer for attaching the top patch is insufficient to extend into the bottom of a trench (i.e., the gap of the first sub-surface 111) for attachment, reducing the sealing performance of the liquid-injection hole 12.
In a specific embodiment, the first sub-surface 111 is a rough surface, and the second sub-surface 113 is a smooth surface (i.e., the surface that is smooth).
Referring to
Optionally, the first sub-surface 111 is annular, the liquid-injection hole 12 is circular, and the ratio of an outer radius R1 of the first sub-surface 111 to the radius R2 of the liquid-injection hole 12 is in a range of 1.2≤R1/R2≤4.8. Specifically, the ratio of the outer radius R1 of the first sub-surface 111 to the radius R2 of the liquid-injection hole 12 may be, but not limited to, 1.2, 1.5, 1.8, 2.0, 2.5, 2.8, 3.0, 3.2, 3.5, 3.75, 4.0, 4.25, 4.5, 4.8, etc. The larger the diameter of the liquid-injection hole 12 is, the more electrolyte passing through per unit time, and the further the electrolyte splashed outwards. If R1/R2 is too small, the electrolyte is likely to splash out of the first sub-surface 111 during filling. The excessively large R1/R2 will cause the waste of laser canning energy and also prolong the machining time, thus increasing the cost of the energy-storage apparatus 200.
Referring to
It should be noted that the welding portion 31 and the first welding mark 33 are both formed during welding of the sealing cap 30 and the top cover 10. During welding of the sealing cap 30 to the top cover 10, the welding material is welded a circle around the periphery of the sealing cap 30 to form the annular welding portion 31, and after the annular welding portion 31 is formed, welding is continued on the top cover 10 to form the first welding mark 33. It can be understood that the first welding mark 33 is the ending point of laser welding.
During laser welding of the sealing cap 30 to the top cover 10, there is a large shrinkage force before the welding material is completely solidified, so that at the end of welding, the relatively large temperature difference at the end is likely to cause end cracks. The arrangement of the first welding mark 33 at a position away from the annular welding portion 31 (there is no need for welding two materials together) can allow the whole annular welding portion 31 to be uniform, improving the sealing performance of the liquid-injection hole 12. The arrangement of the starting and ending points of welding on the first sub-surface 111 outside the welding portion 31 can better prevent the risk of sealing failure due to fine cracks caused by the concentration of stress of the welding portion 31 on the part-to-be welded.
Optionally, the second end portion 333 is located within the range of the first sub-surface 111. This can better prevent the second sub-surface 113 from reflecting laser after the welding is outside the range of the first sub-surface 111 (i.e., the welding reaching the second sub-surface 113).
Optionally, before the sealing cap 30 is welded, the surface of the top cover 10 is cleaned. The aluminum alloy is active and is easy to be oxidized, and a large amount of dust, moisture, etc. are likely to adhere to its surface, so that during welding, if it is not prepared well, the matters adhered to the surface will easily remain on the surface of the aluminum alloy along with the rapid laser welding, thus affecting the quality and welding effect of the aluminum alloy. Therefore, before welding of the aluminum alloy, it is necessary to clean the surface of the aluminum alloy to remove oil stains and the like on the surface. Also, in order to prevent safety threats, such as explosion, caused by oxidation during welding, it is also necessary to thoroughly clean the metal surface to completely remove the oxide film.
In some embodiments, the first sub-surface 111 is annular, the sealing cap 30 is circular, and the ratio of the outer radius R1 of the first sub-surface 111 to the radius R3 of the sealing cap 30 is in a range of 1.45≤R1/R3≤3.65. Specifically, the ratio of the outer radius R1 of the first sub-surface 111 to the radius R3 of the sealing cap 30 may be, but not limited to, 1.45, 1.6, 1.75, 1.88, 2.0, 2.25, 2.5, 2.8, 3.0, 3.2, 3.4, 3.65, etc. If the ratio of the outer radius R1 of the first sub-surface 111 to the radius R3 of the sealing cap 30 is too small, the linewidth of the first sub-surface 111 is insufficient for close attachment of the top patch to the first sub-surface 111 during attachment of the top patch. If the ratio of the outer radius R1 of the first sub-surface 111 to the radius R3 of the sealing cap 30 is large, the linewidth of the first sub-surface 111 is too large, so that when the top patch is attached, the gas between the top patch and the first sub-surface 111 of the top cover 10 cannot be completely discharged through the rough micro-gap of the first sub-surface 111, which is likely to form local bubbles, reducing the sealing effect on the liquid-injection hole 12. When the ratio of the outer radius R1 of the first sub-surface 111 to the radius R3 of the sealing cap 30 is 1.45 to 3.65, it is possible to ensure that the linewidth is sufficient to enhance the close attachment of the top patch to the first sub-surface 111, and also avoid excessively large linewidth of the first sub-surface 111 that will reduce the sealing effect on the liquid-injection hole 12 due to formation of local bubbles caused by the gas between the top patch and the first sub-surface 111 of the top cover 10 being unable to be completely discharged through the rough micro-gap of the first sub-surface 111 during attachment of the top patch.
Referring to
It should be noted that, in this embodiment, the welding portion 31, the first welding mark 33, and the second welding mark 35 are each formed when the sealing cap 30 is welded to the top cover 10. When the sealing cap 30 is welded to the top cover 10, the second welding mark 35 is firstly formed at the side of the first sub-surface 111 of the top cover 10 away from the sealing cap 30, the annular welding portion 31 is then formed between the sealing cap 30 and the top cover 10, and the first welding mark 33 is finally formed at the side of the first sub-surface 111 of the top cover 10 away from the annular welding portion 31. The first welding mark 33 and the second welding mark 35 are approximate to line segments of a straight line that each are roughly tangent to the annular welding portion 31. It can be understood that the first welding mark 33 is the ending point of laser welding, and the second welding mark 35 is a starting point of laser welding.
During welding of the sealing cap 30, when laser welding is performed at the starting position, the temperature of the welding material is not enough, so that the material to be welded cannot reach a molten state desired for good welding, reducing the sealing performance of the liquid-injection hole 12. The arrangement of the second welding mark 35 can allow welding to be performed at a high welding temperature when the welding portion 31 is formed, so that the sealing cap 30 can be better welded to the top cover 10 to better seal the liquid-injection hole 12. Also, in order to also shorten the welding process time (i.e., it is unexpected to prolong the movement time of a laser head during initial welding), the starting point of welding is also set on the outside of the annular welding portion 31, so as to minimize the welding stroke while ensuring the sufficient temperature during forming of the welding portion 31 by welding, thereby improving the welding efficiency.
In other embodiments, the problem of insufficient initial welding temperature can be solved by means of reducing the movement speed of the laser head or welding a circle from the initial position and then surrounding and covering a small section of the initial welded part to achieve uniform welding, and it is not necessary to space the starting point away.
Optionally, the welding portion 31 is annular, the length L2 of the first welding mark 33 satisfies 1.5 mm≤L2≤√{square root over (R12−R42)}, and the length L3 of the second welding mark 35 satisfies 1.5 mm≤L3≤√{square root over (R12−R42)}, where R1 is the outer radius of the first sub-surface 111, and R4 is the outer radius of the welding portion 31. In this way, when the welding portion 31 is formed by welding, the temperature is sufficient, so that the sealing cap 30 can be better welded to the top cover 10 to better seal the liquid-injection hole 12, and the first welding mark 33 and the second welding mark 35 can also be controlled within the range of the first sub-surface 111, avoiding the problem of light reflection during welding due to the marks being beyond the range of the first sub-surface 111.
Optionally, the length L2 of the first welding mark 33 is in a range of 1.5 mm≤L2≤5.5 mm; and specifically, the length L2 of the first welding mark 33 may be, but not limited to, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, etc. If the first welding mark 33 is too short, it is likely to cause end cracks, affecting welding of the sealing cap 30 to the top cover 10, thus affecting the sealing effect. If the first welding mark 33 is too long and is out of the range of the first sub-surface 111, it is likely to cause the problem of light reflection during welding.
Optionally, the length L3 of the second welding mark 35 is in a range of 1.5 mm≤L3≤5.5 mm. Specifically, the length L3 of the second welding mark 35 may be, but not limited to, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, etc. If the second welding mark 35 is too short, the temperature of the welding material is insufficient during forming of the welding portion 31 by welding, which affects welding of the sealing cap 30 to the top cover 10, thus affecting the sealing effect. If the second welding mark 35 is too long and is out of the range of the second sub-surface 113, it is likely to cause the problem of light reflection during welding.
In a specific embodiment, the welding portion 31 is annular, the first welding mark 33 and the second welding mark 35 are straight, and the first welding mark 33 and the second welding mark 35 are both tangent to the welding portion 31. The first welding mark 33 and the second welding mark 35 are straight, and the straight welding marks can shorten the movement path of the laser welding head, improving the welding efficiency.
In another specific embodiment, the welding portion 31 is annular, and the first welding mark 33 is straight and is tangent to the welding portion 31; and the second welding mark 35 is arc, and the second welding mark 35 is tangent to the welding portion 31. When the sealing cap 30 is welded to the top cover 10 for laser welding, it is not necessary to align the starting position to a specific position, and the position tangent to the sealing cap 30 may be adjusted by means of an arc, so that the welding operation is more convenient, and the requirement for the accuracy of the starting position is low.
Referring to
Optionally, in some embodiments, the first welding mark 33 is straight, and an angle α between a line connecting the center of the sealing cap 30 and the first end portion 331 and the first welding mark 33 is in a range of 700≤α≤120°. Specifically, the angle α between the line connecting the center of the sealing cap 30 and the first end portion 331 and the first welding mark 33 may be, but not limited to, 70°, 75°, 80°, 85°, 90°, 95°, 100°, 105°, 110°, 115°, 120°, etc. In this angle range, the path of laser welding is smoother, so as to avoid reduction of the overall welding uniformity and reduction of the sealing performance of welding caused by the accumulation of molten metal at the welded part due to a relatively large turning angle.
In some embodiments, the ratio of the outer radius R4 of the welding portion 31 to the length L3 of the second welding mark 35 is in a range of 0.4≤R4/L3≤2.8. Specifically, the ratio of the outer radius R4 of the welding portion 31 to the length L3 of the second welding mark 35 may be, but not limited to, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, etc. If the ratio of the outer radius R4 of the welding portion 31 to the length L2 of the second welding mark 35 is too large, the second welding mark 35 is too short, which is likely to cause end cracks, affecting welding of the sealing cap 30 to the top cover 10, thus affecting the sealing effect. If the ratio of the outer radius R4 of the welding portion 31 to the length L2 of the second welding mark 35 is too small, the second welding mark 35 is too long and is out of the range of the first sub-surface 111, which is likely to cause the problem of light reflection during welding. When the ratio of the outer radius R4 of the welding portion 31 to the length L2 of the second welding mark 35 is 0.4 to 2.8, during forming of the welding portion 31 by welding, the temperature is sufficient, so that the sealing cap 30 can be better welded to the top cover 10 to better seal the liquid-injection hole 12, and the second welding mark 35 can also be controlled within the range of the first sub-surface 111, avoiding the problem of light reflection during welding due to the marks being beyond the range of the first sub-surface 111.
Optionally, the second welding mark 35 is straight, and an angle β between a line connecting the center of the sealing cap 30 and the third end portion 351 and the second welding mark 35 is in a range of 70°≤β≤120°. Specifically, the angle β between the line connecting the center of the sealing cap 30 and the third end portion 351 and the second welding mark 35 may be, but not limited to, 70°, 75°, 80°, 85°, 90°, 95° 100°, 105°, 110°, 115°, 120°, etc. In this angle range, the path of laser welding is smoother, so as to avoid reduction of the overall welding uniformity and reduction of the sealing performance of welding caused by the accumulation of molten metal at the welded part due to a relatively large turning angle.
Referring to
Optionally, the abutting sub-surface 115 is recessed from the first sub-surface 111, the sealing cap 30 is located in a recess formed by the abutting sub-surface 115, and the surface of the sealing cap 30 close to the first surface 11 is flush with the first sub-surface 111. This can prevent the sealing cap 30 from exceeding the top cover 10, so that the surface of the top cover 10 is flatter and can thus be better attached to the top patch during attachment of the top patch, so that the liquid-injection hole 12 can be better sealed.
It can be understood that the liquid-injection hole 12 extends through the abutting sub-surface 115.
Referring to
It should be noted that when the end cover assembly 100 is for the energy-storage apparatus 200, the first surface 11 is closer to an appearance surface of the energy-storage apparatus 200 than the second surface 13, that is, the surface to which the top patch is attached.
In this embodiment, when the end cover assembly 100 is mounted to the energy-storage apparatus 200, when the electrolyte is filled through the liquid-injection hole 12, the electrolyte is filled into the energy-storage apparatus 200 from the side of the liquid-injection hole 12 close to the first surface 11, and the protrusion 14 provided on the second surface 13 has the effect of guiding and limiting the electrolyte and can better prevent the electrolyte from flowing to the second surface 13 of the top cover 10, which will cause the waste of the electrolyte and increase the risk of corrosion of the top cover 10.
Referring to
Referring to
Optionally, the groove 15 has a linewidth S2 in a range of 1.2 mm≤S2≤4.6 mm. Specifically, the linewidth S2 of the groove 15 may be, but not limited to 1.2 mm, 1.5 mm, 1.7 mm, 2.2 mm, 2.4 mm, 2.7 mm, 2.8 mm, 3.0 mm, 3.2 mm, 3.6 mm, 3.8 mm, 4.0 mm, 4.2 mm, 4.6 mm, etc. If the linewidth S2 of the groove 15 is too small, the width is not enough to well prevent the electrolyte from spreading to the outside of the groove 15 to cause the waste of the electrolyte. If the linewidth S2 of the groove 15 is too large, the structural strength of the top cover 10 turning around the liquid-injection hole 12 will be reduced, which is likely to cause protruding deformation during subsequent use. When the linewidth S2 of the groove 15 is 1.2 mm to 4.6 mm, the groove 15 may have a sufficient width such that the electrolyte will not spread to the outside of the groove 15 to cause the waste of the electrolyte, and it is also possible to prevent the protruding deformation during subsequent use due to the reduction of the structural strength of the top cover 10 turning around the liquid-injection hole 12.
Referring to
Referring to
In a specific embodiment, the second peripheral side wall 553 is parallel to the surface of the first plastic sub-member 55 facing the second plastic sub-member 56. In another specific embodiment, the second peripheral side wall 553, the surface of the first plastic sub-member 55 facing the second plastic sub-member 56, and the surface of the second plastic sub-member 56 facing the first plastic sub-member 55 are parallel to one another. In this way, the first plastic sub-member 55 and the second plastic sub-member 56 each have more regular appearance, which can better provide avoidance for the third plastic sub-member 57 and the fourth plastic sub-member 58. In addition, since the first plastic sub-member 55 and the second plastic sub-member 56 are equal in length in the first direction, the third plastic sub-member 57 and the fourth plastic sub-member 58 can be made symmetrical in the second direction, so that during assembly, the third plastic sub-member 57 and the fourth plastic sub-member 58 can be assembled interchangeably, reducing the assembly accuracy.
Also referring to
Optionally, the explosion-proof sheet 21 is provided with scorings (not shown), such that when the internal pressure of the energy-storage apparatus 200 increases to reach a certain value, a fracture will occur for blasting to release pressure of the energy-storage apparatus 200.
In some embodiments, the end cover assembly 100 in the embodiment of the present disclosure further includes a protective sheet 23. The protective sheet 23 is arranged on the side of the explosion-proof sheet 21 away from the lower plastic member 50 (i.e., the side of the first surface 11 of the top cover 10) to seal the explosion-proof hole 19 and protect the explosion-proof sheet 21, so as to prevent the electrolyte inside the energy-storage apparatus 200 from overflowing caused by foreign objects hitting the explosion-proof sheet 21 and damaging the explosion-proof sheet 21.
In some embodiments, the end cover assembly 100 in the embodiments of the present disclosure further includes a top patch (not shown). The top patch is arranged on the first surface 11 of the top cover 10 and the sealing cap 30.
Referring to
In some embodiments, the end cover assembly 100 in the embodiments of the present disclosure further includes a positive-electrode upper plastic member 61 and a negative-electrode upper plastic member 63. The positive-electrode upper plastic member 61 is at least partially located between the positive-electrode metal pressing block 41 and the top cover 10 to insulate the positive-electrode metal pressing block 41 from the top cover 10. The negative-electrode upper plastic member 63 is at least partially located between the negative-electrode metal pressing block 43 and the top cover 10 to insulate the negative-electrode metal pressing block 43 from the top cover 10.
Optionally, the positive-electrode upper plastic member 61 may be, but not limited to, an insulating component such as a resin or rubber. The negative-electrode upper plastic member 63 may be, but not limited to, an insulating component such as a resin or rubber.
In some embodiments, the end cover assembly 100 in the embodiments of the present disclosure further includes a positive pole 71 and a negative pole 73. The positive pole 71 sequentially penetrates through the lower plastic member 50, the top cover 10, the positive-electrode upper plastic member 61, and the positive-electrode metal pressing block 41 and is welded to the positive-electrode metal pressing block 41, and the end of the positive pole 71 away from the metal pressing block is welded to the positive-electrode adapter sheet 231 to achieve electrical connection between the positive-electrode metal pressing block 41 and a positive-electrode sheet. The negative pole 73 sequentially penetrates through the lower plastic member 50, the top cover 10, the negative-electrode upper plastic member 63, and the negative-electrode metal pressing block 43 and is welded to the negative-electrode metal pressing block 43, and the end of the negative pole 73 away from the metal pressing block is welded to the negative-electrode adapter sheet 233 to achieve electrical connection between the negative-electrode metal pressing block 43 and a negative-electrode sheet.
Optionally, the positive pole 71 and the negative pole 73 each include a flange portion (not shown) and a boss (not shown) protruding from a surface of the flange portion. The flange portion is located between the lower plastic member 50 and the positive-electrode adapter sheet 231/negative-electrode adapter sheet 233 and is welded to the positive-electrode adapter sheet 231/negative-electrode adapter sheet 233. The boss sequentially penetrates through the lower plastic member 50, the top cover 10, the positive-electrode upper plastic member 61/negative-electrode upper plastic member 63, and the positive-electrode metal pressing block 41/negative-electrode metal pressing block 43, such that the positive-electrode metal pressing block 41 is electrically connected to the positive-electrode adapter sheet 231 by means of the positive pole 71, and the negative-electrode metal pressing block 43 is electrically connected to the negative-electrode adapter sheet 233 by means of the negative pole 73.
Optionally, the flange portion is arranged on the side of the lower plastic member 50 away from the top cover, and the boss penetrates through the first through hole 18 and the second through hole 54; and the boss has a central axis, and the pole 70 is rotationally symmetrical about the central axis. In this way, there is no need to distinguish left and right directions during assembly of the pole 70, and the assembly can be completed by insertion after direct alignment of the long side, reducing the assembly requirement of the pole 70.
In some embodiments, the end cover assembly 100 in the embodiments of the present disclosure further includes a sealing ring 80, the boss of the positive pole 71 and the boss of the negative pole 73 are each sleeved with the sealing ring 80, and the sealing ring 80 is configured to insulate the positive pole 71/negative pole 73 from the top cover 10 and seal the gap between the positive pole 71/negative pole 73 and the top cover 10.
In some embodiments, the end cover assembly 100 in the embodiments of the present disclosure further includes a sealing pin 90. The sealing pin 90 penetrates through the liquid-injection hole 12 for sealing the liquid-injection hole 12. After the energy-storage apparatus 200 is assembled and filled with the electrolyte, the sealing pin 90 is firstly arranged in the liquid-injection hole 12, the sealing cap 30 is then arranged on the first surface 11 of the top cover 10 and the sealing pin 90, and the sealing cap 30 is welded to the top cover 10.
Optionally, the sealing pin 90 may be, but not limited to, an insulating component such as a resin or rubber.
The terms of “embodiment” and “implementation” mentioned in the present disclosure means that the specific features, structures, or characteristics described with reference to the embodiments may be encompassed in at least one embodiment of the present disclosure. The phrase at various locations in the specification does not necessarily refer to the same embodiment, or an independent or alternative embodiment exclusive of another embodiment. Those skilled in the art should understand explicitly and implicitly that the embodiments described in the present disclosure may be combined with other embodiments. In addition, it should also be understood that the features, structures or characteristics described in the embodiments of the present disclosure may be combined as desired to obtain embodiments without departing from the spirit and scope of the technical solution of the present disclosure if there is no contradiction between the embodiments.
Finally, it should be noted that the above implementations are merely used for illustrating rather than limiting the technical solutions of the present disclosure; and although the present disclosure has been described in detail with reference to the preferred implementations, those skilled in the art should understand that modifications or equivalent substitutions may be made to the technical solutions of the present disclosure without departing from the spirit and scope of the technical solutions of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202310091082.4 | Feb 2023 | CN | national |
