CN214625190U

CN214625190U - Cylindrical lithium ion battery cover plate assembly

Info

Publication number: CN214625190U
Application number: CN202022997771.6U
Authority: CN
Inventors: 陈保国
Original assignee: Tianjin EV Energies Co Ltd
Current assignee: Tianjin EV Energies Co Ltd
Priority date: 2020-12-14
Filing date: 2020-12-14
Publication date: 2021-11-05
Anticipated expiration: 2030-12-14

Abstract

The utility model provides a cylinder lithium ion battery apron subassembly, including utmost point ear body, the apron, the end cap, connection piece body and rivet, the apron upper surface is equipped with utmost point ear mount table, utmost point ear mount table is equipped with a plurality of utmost point ear through holes, be equipped with a plurality of utmost point ear through-holes on the utmost point ear body, the apron upper surface is equipped with explosion-proof area, be equipped with in the explosion-proof area and annotate the liquid hole, the end cap with annotate liquid hole clearance fit, the apron bottom is equipped with the connection piece body, connection piece body one end is equipped with a plurality of connection piece through-holes, a plurality of utmost point ear through-holes, the quantity of a plurality of connection piece through-holes and rivet equals, and the one-to-one, supreme every connection piece through-hole of passing in proper order is followed to every rivet, every utmost point ear through-hole and every utmost point ear through-hole, realize utmost point ear body, the fixed connection between apron and the connection piece body. The utility model reduces the number of the assembled parts by optimizing the structure of the parts; the material structure is optimized, and the insulation voltage-resistant grade and the safety of opening the explosion-proof valve in thermal runaway are improved.

Description

Cylindrical lithium ion battery cover plate assembly

Technical Field

The utility model belongs to the power battery field especially relates to a cylinder lithium ion battery apron subassembly.

Background

Along with the development and progress of new energy automobile technology, higher requirements are put forward on the energy density, the cycle life, the safety and the reliability of the lithium ion battery. The advantages of the cylindrical battery in terms of process maturity and inhibition of negative electrode expansion are more and more obvious, so that the size requirement of the cylindrical battery is more diversified and greatly increased. The positive and negative cover plate assemblies of the cylindrical battery are important components of the cylindrical battery, and play an important role in the aspects of the sealing property, the safety, the positive and negative output and the like of the battery. The cylindrical battery anode and cathode cover plate assembly at the present stage generally uses pure metal materials as supports, particularly aluminum alloy, and is assisted with corresponding plastic parts for insulation protection, so that anode and cathode tabs can be normally output.

As described in patent CN 209389070U, the anode and cathode cover plates of currently commonly used cylindrical lithium ion batteries are usually made of pure metal materials, corresponding insulating materials are installed on both sides of the cover plate to insulate the cover plate and the anode and cathode tabs, and a sealing gasket is installed at a fixing rivet to ensure the sealing performance of the entire battery case. The conventional positive and negative electrode cover plate assembly is complex in structure, various in part variety and high in assembly difficulty. Only one insulating sheet with small size is arranged between the pole lug and the cover plate, the insulating protection area is small, after the battery system is formed, the integral insulating and pressure-resistant grade is low, and the short circuit risk is relatively high.

The conventional positive and negative electrode tabs are small in size and low in overcurrent capacity, and for a large-capacity lithium ion battery, the conventional structure cannot meet overcurrent performance, the temperature rise is high, the temperature rise exceeds the safe use range, the high temperature causes serious problems such as the power limit of the whole vehicle and even thermal runaway, and the like, and the damage is caused to property and personal safety.

The explosion-proof valve of the existing structure is arranged on the metal cover plate, the local strength of the cover plate is weakened through a stamping process, once the battery is out of control due to heat, gas is generated inside the battery, and the explosion area on the cover plate can be broken through when the air pressure reaches a certain degree. And the explosion-proof area on the metal cover plate is smaller, the pressure relief opening is single, the pressure relief opening is positioned at the edge of the cover plate, the exhaust path is unique, and the blockage is easy. Along with the aggravation of the thermal runaway reaction degree, the pressure relief opening is small, so that the pressure and the temperature of the sprayed gas are relatively high, the influence on adjacent batteries is also large, the heat diffusion is easily caused, and the larger loss is caused.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention is directed to a cylindrical lithium ion battery cover plate assembly, which reduces the number of assembled parts by optimizing the structure of the parts; the material structure is optimized, and the insulation voltage-resistant grade and the safety of opening the explosion-proof valve in thermal runaway are improved.

In order to achieve the above purpose, the technical scheme of the utility model is realized like this:

a cylindrical lithium ion battery cover plate component, which comprises a tab body, a cover plate, a plug, a connecting plate body and a rivet,

the upper surface of the cover plate is provided with a pole lug mounting platform, the cover plate and the pole lug mounting platform form an integrated structure, the pole lug mounting platform is provided with a plurality of pole lug through holes, the pole lug body is arranged at the upper part of the pole lug mounting platform, the pole lug body is provided with a plurality of pole lug through holes,

apron upper surface one side is equipped with the explosion-proof area, be equipped with in the explosion-proof area and annotate the liquid hole, the end cap with annotate liquid hole clearance fit, the apron bottom is equipped with the connection piece body, connection piece body one end is equipped with a plurality of connection piece through-holes, a plurality of utmost point ear through-holes, the quantity of a plurality of connection piece through-holes and rivet equals, and the one-to-one, supreme every connection piece through-hole, every utmost point ear through-hole and every utmost point ear through-hole of passing in proper order are down followed to every rivet, realize the fixed connection between utmost point ear body, apron and the connection piece body.

Further, the apron includes a metal ring and a working of plastics, a metal ring and a working of plastics injection moulding, a metal ring outer lane is equipped with the outer step of a number with the cylinder casing of battery matched with, and an outer step passes through laser welding with the cylinder casing, a metal ring inner circle is equipped with interior step No. one, working of plastics top edge is equipped with annular groove No. one, a step and annular groove mutually support, the material of a metal ring is the aluminum alloy, the material of a working of plastics is modified plastics, modified plastics is polyphenyl ether, polystyrene, the fine blend of glass is modified.

Further, the lug mounting platform comprises a rectangular protective convex wall, the rectangular protective convex wall and the cover plate form the lug mounting platform, the lug body is matched with the rectangular protective convex wall, the lug body is mounted into the rectangular protective convex wall, the horizontal line where the top of the rectangular protective convex wall is located is higher than the horizontal line where the top of the first metal ring is located, and the horizontal line where the top of the rectangular protective convex wall is located is lower than the horizontal line where the top of the lug body is located; the explosion-proof area is arranged on one side of the rectangular protective convex wall, the explosion-proof area is in a circular groove shape, and the liquid injection hole is arranged at the center of the bottom of the explosion-proof area.

Further, the apron includes No. two rings and No. two working of plastics, No. two rings and No. two working of plastics injection moulding, No. two ring outer races are equipped with the outer step of No. two with the cylinder casing matched with of battery, and No. two outer steps pass through laser welding with the cylinder casing, No. two ring inner races are equipped with No. two interior steps, No. two working of plastics top edge is equipped with No. two annular grooves, No. two steps and No. two annular grooves mutually support, No. two the material of ring is the aluminum alloy, the material of No. two working of plastics is modified plastics, modified plastics is polyphenyl ether, polystyrene, the fine blend of glass is modified.

Furthermore, the lug mounting table comprises a first rectangular boss, the first rectangular boss and the cover plate form the lug mounting table, and the horizontal line where the top of the first rectangular boss is located is higher than the horizontal line where the top of the second metal ring is located; the explosion-proof area is annular groove form, annotates the liquid hole and sets up in explosion-proof area bottom, and annotates the liquid hole and set up in rectangle boss one side.

Further, the apron includes No. three rings and No. three working of plastics, No. three rings and No. three working of plastics injection moulding, No. three rings outer lane is equipped with the outer step of No. three of cylinder casing matched with the battery, and No. three outer step passes through laser welding with cylinder casing, No. three rings inner circle is equipped with No. three interior steps, No. three working of plastics top edge is equipped with No. three annular grooves, No. three step and No. three annular grooves mutually support, the material of No. three rings is the aluminum alloy, the material of No. three working of plastics is modified plastics, modified plastics is polyphenyl ether, polystyrene, the fine blend of glass is modified.

Further, the lug mounting table comprises a second rectangular boss, the second rectangular boss and the cover plate form the lug mounting table, and the horizontal line where the top of the second rectangular boss is located is higher than the horizontal line where the top of the second metal ring is located; the explosion-proof area is circular recess form, annotates the liquid hole and sets up at explosion-proof area bottom center, and annotates the liquid hole and set up in rectangle boss one side.

Furthermore, the material of the plug is liquid level modified plastic, and the plug is matched with the liquid injection hole through quick-drying epoxy glue.

Furthermore, a sealing ring is arranged between each rivet and the cover plate.

Compared with the prior art, a cylinder lithium ion battery apron subassembly have following advantage:

(1) a cylinder lithium ion battery apron subassembly, the kind and the quantity of assembling spare part still less on the apron, the equipment is more simplified, alleviates apron weight, reduction in production cost.

(2) A cylinder lithium ion battery apron subassembly, make the holistic withstand voltage level of battery higher.

(3) A cylinder lithium ion battery apron subassembly, battery thermal runaway back, explosion-proof valve can be opened earlier, explosion-proof valve evenly distributed is on the apron, the pressure release mouth area is bigger, the gas pressure who erupts is lower, the whole security of battery system obtains promoting.

Drawings

The accompanying drawings, which form a part hereof, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without undue limitation. In the drawings:

fig. 1 is a schematic view of a first embodiment of a cylindrical lithium ion battery cover plate assembly according to an embodiment of the present invention;

fig. 2 is a schematic view of a cylindrical lithium ion battery cover plate assembly according to a second embodiment of the present invention;

fig. 3 is a schematic diagram of a cylindrical lithium ion battery cover plate assembly according to a third embodiment of the present invention.

Description of reference numerals:

1. a tab body; 2. a cover plate; 21. a first metal ring; 211. a first outer step; 212. an inner step I; 22. a first plastic part; 221. a first annular groove; 23. a second metal ring; 231. a second outer step; 232. a second inner step; 24. a second plastic part; 241. a second annular groove; 25. a third metal ring; 251. a third outer step; 252. a third inner step; 26. a third plastic part; 261. a third annular groove; 3. a plug; 4. a connecting sheet body; 5. riveting; 6. a tab mounting table; 61. a rectangular protective convex wall; 62. a first rectangular boss; 63. a second rectangular boss; 7. a liquid injection hole; 8. an explosion-proof area; 9. and (5) sealing rings.

Detailed Description

It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

The first embodiment is as follows:

a cover plate 2 assembly of a cylindrical lithium ion battery is shown in figure 1 and comprises a tab body 1, a cover plate 2, a plug 3, a connecting plate body 4 and a rivet 5, wherein the tab body 1 is made of aluminum which can reduce the material cost and the assembly weight,

the upper surface of the cover plate 2 is provided with a pole lug installation platform 6, the cover plate 2 and the pole lug installation platform 6 form an integrated structure, the pole lug installation platform 6 is provided with a plurality of pole lug through holes, the pole lug body 1 is arranged on the upper part of the pole lug installation platform 6, the pole lug body 1 is provided with a plurality of pole lug through holes,

the upper surface of the cover plate 2 is provided with an explosion-proof area 8, the explosion-proof area 8 is internally provided with a liquid injection hole 7, the plug 3 is in clearance fit with the liquid injection hole 7, the bottom of the cover plate 2 is provided with a connecting plate body 4, one end of the connecting plate body 4 is provided with a plurality of connecting plate through holes, a plurality of tab through holes and rivets 5 are equal in number and are in one-to-one correspondence, and each rivet 5 sequentially passes through each connecting plate through hole, each tab through hole and each tab through hole from bottom to top, so that the fixed connection among the tab body 1, the cover plate 2 and the connecting plate body 4 is realized;

the positive electrode of the connecting sheet body 4 is made of aluminum, and the negative electrode of the connecting sheet body is made of copper; the positive connecting sheet is connected with a positive plate in the battery, and the negative connecting sheet is connected with a negative plate in the battery; 4 connecting sheet through holes are formed in the connecting sheet body 4; the rivet 5 corresponding to the positive connecting sheet is a positive rivet 5, the rivet 5 corresponding to the negative connecting sheet is a negative rivet 5, the rivet 5 and the connecting sheet are welded together in advance through a super wind wave, and finally the rivet is assembled and fastened with the tab body 1 through a spin riveting process;

the cover plate 2 comprises a first metal ring 21 and a first plastic part 22, the first metal ring 21 and the first plastic part 22 are formed in an injection molding mode, the outer ring of the first metal ring 21 is provided with a first outer step 211 matched with a cylindrical shell of a battery, the first outer step 211 and the cylindrical shell are welded in a laser mode, the inner ring of the first metal ring 21 is provided with a first inner step 212, the edge of the top of the first plastic part 22 is provided with a first annular groove 221, the first inner step 212 and the first annular groove 221 are matched with each other, the first metal ring 21 is made of aluminum alloy, the first plastic part 22 is made of modified plastic, the modified plastic is polyphenylene oxide, polypropylene and glass fiber blended and modified, the modified plastic has low shrinkage rate, and is about 0.2% -0.7%, and the structural shape of the part is guaranteed; the tensile strength is more than 80MPa, so that the part has better impact resistance; meanwhile, the modified material is resistant to organic solvents such as electrolyte and the like, the performance of the material is not degraded after long-time use, and the long service life of the battery is ensured; the material also has excellent electrical insulation performance, the surface resistivity of the material is more than 1017 omega cm, and the electrical safety is ensured; the thermal deformation temperature of the modified material is 120-140 ℃, the flame retardant grade of UL90-V0 is met, the explosion-proof valve can be opened in the early stage of thermal runaway, and when the gas production rate is increased along with the aggravation of the thermal runaway, the whole first plastic part 22 is melted, and an exhaust channel is increased.

The tab mounting table 6 comprises a rectangular protective convex wall 61, the rectangular protective convex wall 61 and the cover plate 2 form the tab mounting table 6, the tab body 1 is matched with the rectangular protective convex wall 61, the tab body 1 is mounted in the rectangular protective convex wall 61, the horizontal line where the top of the rectangular protective convex wall 61 is located is higher than the horizontal line where the top of the first metal ring 21 is located, the horizontal line where the top of the rectangular protective convex wall 61 is located is lower than the horizontal line where the top of the tab body 1 is located, and welding of the upper surface of the tab body 1 is not affected; explosion-proof area 8 sets up in rectangle protection convex wall 61 one side, and explosion-proof area 8 is circular recess form, annotates liquid hole 7 and sets up in explosion-proof area 8 bottom center department.

The material of end cap 3 also is modified plastics, and end cap 3 passes through the rapid-curing cutback epoxy glue and annotates liquid hole 7 cooperation, guarantees the leakproofness, all is equipped with a sealing washer 9 between every rivet 5 and apron 2, and the material of sealing washer 9 is fluororubber, high temperature resistant, resistant oil, resistant chemical's corruption.

Example two:

a cylindrical lithium ion battery cover plate 2 assembly is shown in figure 2 and comprises a tab body 1, a cover plate 2, a plug 3, a connecting plate body 4 and a rivet 5,

the positive electrode of the connecting sheet body 4 is made of aluminum, and the negative electrode of the connecting sheet body is made of copper; the positive connecting sheet is connected with a positive plate in the battery, and the negative connecting sheet is connected with a negative plate in the battery; 2 connecting sheet through holes are formed in the connecting sheet body 4; the rivet 5 corresponding to the positive connecting sheet is a positive rivet 5, the rivet 5 corresponding to the negative connecting sheet is a negative rivet 5, the rivet 5 and the connecting sheet are welded together in advance through a super wind wave, and finally the rivet is assembled and fastened with the tab body 1 through a spin riveting process;

the cover plate 2 comprises a second metal ring 23 and a second plastic part 24, the second metal ring 23 and the second plastic part 24 are formed by injection molding, a second outer step 231 matched with a cylindrical shell of the battery is arranged on an outer ring of the second metal ring 23, the second outer step 231 is welded with the cylindrical shell by laser, a second inner step 232 is arranged on an inner ring of the second metal ring 23, a second annular groove 241 is arranged at the edge of the top of the second plastic part 24, the second inner step 232 is matched with the second annular groove 241, the second metal ring 23 is made of aluminum alloy, the second plastic part 24 is made of modified plastic, the modified plastic is modified by blending of polyphenyl ether, polyethylene and glass fiber, the modified plastic has lower shrinkage rate, and the shrinkage rate is about 0.2-0.7%, and the structural shape of the part is ensured; the tensile strength is more than 80MPa, so that the part has better impact resistance; meanwhile, the modified material is resistant to organic solvents such as electrolyte and the like, the performance of the material is not degraded after long-time use, and the long service life of the battery is ensured; the material also has excellent electrical insulation performance, the surface resistivity of the material is more than 1017 omega cm, and the electrical safety is ensured; the thermal deformation temperature of the modified material is 120-140 ℃, the flame retardant grade of UL90-V0 is met, the explosion-proof valve can be opened in the early stage of thermal runaway, and when the gas production rate is increased along with the aggravation of the thermal runaway, the whole first plastic part 22 is melted, and an exhaust channel is increased.

The tab mounting table 6 comprises a first rectangular boss 62, the first rectangular boss 62 and the cover plate 2 form the tab mounting table 6, and the horizontal line where the top of the first rectangular boss 62 is located is higher than the horizontal line where the top of the second metal ring 23 is located; explosion-proof area 8 is the annular groove form, annotates liquid hole 7 and sets up in explosion-proof area 8 bottom, and annotates liquid hole 7 and set up in rectangle boss one side.

The plug 3 is also made of modified plastics, and the plug 3 is matched with the liquid injection hole 7 through quick-drying epoxy glue to ensure the sealing property; a sealing ring 9 is arranged between each rivet 5 and the cover plate 2, and the sealing ring 9 is made of fluororubber and is resistant to high temperature, oil and chemical corrosion.

Example three:

a cylindrical lithium ion battery cover plate 2 assembly is shown in figure 3 and comprises a tab body 1, a cover plate 2, a plug 3, a connecting plate body 4 and a rivet 5,

the cover plate 2 comprises a third metal ring 25 and a third plastic part 26, the third metal ring 25 and the third plastic part 26 are formed by injection molding, the outer ring of the third metal ring 25 is provided with a third outer step 251 matched with a cylindrical shell of a battery, the third outer step 251 and the cylindrical shell are welded by laser, the inner ring of the third metal ring 25 is provided with a third inner step 252, the edge of the top of the third plastic part 26 is provided with a third annular groove 261, the third inner step 252 and the third annular groove 261 are matched with each other, the third metal ring 25 is made of aluminum alloy, the third plastic part 26 is made of modified plastic, the modified plastic is polyphenylene oxide, polypropylene and glass fiber blended and modified, the modified plastic has lower shrinkage rate, and is about 0.2-0.7%, and the structural shape of the part is ensured; the tensile strength is more than 80MPa, so that the part has better impact resistance; meanwhile, the modified material is resistant to organic solvents such as electrolyte and the like, the performance of the material is not degraded after long-time use, and the long service life of the battery is ensured; the material also has excellent electrical insulation performance, the surface resistivity of the material is more than 1017 omega cm, and the electrical safety is ensured; the thermal deformation temperature of the modified material is 120-140 ℃, the flame retardant grade of UL90-V0 is met, the explosion-proof valve can be opened in the early stage of thermal runaway, and when the gas production rate is increased along with the aggravation of the thermal runaway, the whole first plastic part 22 is melted, and an exhaust channel is increased.

The tab mounting table 6 comprises a second rectangular boss 63, the second rectangular boss 63 and the cover plate 2 form the tab mounting table 6, and the horizontal line where the top of the second rectangular boss 63 is located is higher than the horizontal line where the top of the second metal ring 23 is located; explosion-proof area 8 is circular recess form, annotates liquid hole 7 and sets up at explosion-proof area 8 bottom center, and annotates liquid hole 7 and set up in rectangle boss one side.

The material of the plug 3 is also modified plastics, and the plug 3 is matched with the liquid injection hole 7 through quick-drying epoxy glue, so that the sealing performance is ensured. A sealing ring 9 is arranged between each rivet 5 and the cover plate 2, and the sealing ring 9 is made of fluororubber and is resistant to high temperature, oil and chemical corrosion.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a cylinder lithium ion battery apron subassembly which characterized in that: comprises a tab body, a cover plate, a plug, a connecting piece body and a rivet,

the apron upper surface is equipped with explosion-proof area, is equipped with in the explosion-proof area and annotates the liquid hole, the end cap with annotate liquid hole clearance fit, the apron bottom is equipped with the connection piece body, connection piece body one end is equipped with a plurality of connection piece through-holes, a plurality of utmost point ear through-holes, the quantity of a plurality of connection piece through-holes and rivet equals, and the one-to-one, supreme every connection piece through-hole, every utmost point ear through-hole and every utmost point ear through-hole of passing in proper order are down followed to every rivet, realize the fixed connection between utmost point ear body, apron and the connection piece body.

2. The cylindrical lithium ion battery cover plate assembly of claim 1, wherein: the apron includes a metal ring and working of plastics, a metal ring and a working of plastics injection moulding, a metal ring outer lane be equipped with the cylinder casing of battery matched with outer step No. one, and outer step and cylinder casing pass through laser welding, a metal ring inner circle is equipped with interior step No. one, working of plastics top edge is equipped with annular groove No. one, interior step and annular groove mutually support No. one, the material of a metal ring is the aluminum alloy.

3. The cylindrical lithium ion battery cover plate assembly of claim 2, wherein: the lug mounting platform comprises a rectangular protective convex wall, the rectangular protective convex wall and the cover plate form the lug mounting platform, the lug body is matched with the rectangular protective convex wall, the lug body is mounted into the rectangular protective convex wall, the horizontal line where the top of the rectangular protective convex wall is located is higher than the horizontal line where the top of the first metal ring is located, and the horizontal line where the top of the rectangular protective convex wall is located is lower than the horizontal line where the top of the lug body is located; the explosion-proof area is arranged on one side of the rectangular protective convex wall, the explosion-proof area is in a circular groove shape, and the liquid injection hole is arranged at the center of the bottom of the explosion-proof area.

4. The cylindrical lithium ion battery cover plate assembly of claim 1, wherein: the apron includes No. two rings and No. two working of plastics, No. two rings and No. two working of plastics injection moulding, No. two ring outer races are equipped with the outer step of No. two with the cylinder casing matched with of battery, and No. two outer steps pass through laser welding with the cylinder casing, No. two ring inner races are equipped with No. two interior steps, No. two working of plastics top edge is equipped with No. two annular grooves, No. two interior steps and No. two annular grooves mutually support, No. two the material of rings is the aluminum alloy, the material of No. two working of plastics is modified plastics, modified plastics is polyphenyl ether, polystyrene, the fine blending of glass is modified.

5. The cylindrical lithium ion battery cover plate assembly of claim 4, wherein: the lug mounting table comprises a first rectangular boss, the first rectangular boss and the cover plate form the lug mounting table, and the horizontal line where the top of the first rectangular boss is located is higher than the horizontal line where the top of the second metal ring is located; the explosion-proof area is annular groove form, annotates the liquid hole and sets up in explosion-proof area bottom, and annotates the liquid hole and set up in rectangle boss one side.

6. The cylindrical lithium ion battery cover plate assembly of claim 1, wherein: the apron includes No. three rings and No. three working of plastics, No. three rings and No. three working of plastics injection moulding, No. three rings outer lane be equipped with the cylinder casing matched with No. three outer steps of battery, and No. three outer steps pass through laser welding with the cylinder casing, No. three rings inner circle is equipped with No. three interior steps, No. three working of plastics top edge is equipped with No. three annular grooves, No. three interior steps and No. three annular grooves mutually support, the material of No. three rings is the aluminum alloy.

7. The cylindrical lithium ion battery cover plate assembly of claim 6, wherein: the lug mounting table comprises a second rectangular boss, the second rectangular boss and the cover plate form the lug mounting table, and the horizontal line where the top of the second rectangular boss is located is higher than the horizontal line where the top of the second metal ring is located; the explosion-proof area is circular recess form, annotates the liquid hole and sets up at explosion-proof area bottom center, and annotates the liquid hole and set up in rectangle boss one side.

8. The cylindrical lithium ion battery cover plate assembly of claim 1, wherein: the material of the plug is liquid level modified plastic, and the plug is matched with the liquid injection hole through quick-drying epoxy glue.

9. The cylindrical lithium ion battery cover plate assembly of claim 1, wherein: and a sealing ring is arranged between each rivet and the cover plate.