阅读说明：本技术 一种锂电池正极端封口结构及其制造方法 (Sealing structure for positive electrode end of lithium battery and manufacturing method thereof ) 是由 朱效铭 于 2021-03-15 设计创作，主要内容包括：本发明公开了一种锂电池正极端封口结构及其制造方法,包括下端封闭、上端开口的电池外壳和密封封闭开口的集电体,该集电体内设有上下贯通的中孔,集电体顶部设有封闭中孔的正极帽,集电体底部与正极耳焊接形成导电,主要是将集电体中孔的孔壁一直向上延伸,并使该孔壁顶部能够向内翻折出卷边以包覆在阀体顶部,再将正极帽盖合卷边而封闭中孔,从而使得正极帽能够直接与集电体形成导电输出,避免传统结构中还需通过阀体间接导电输出电流的麻烦；因此,改进后的正极端封口结构设计更加简单、安装工序也得到简化,其结合相应的制造方法,还具有导电连接可靠性好、导电效率高和使用安全等优点。(The invention discloses a sealing structure of a lithium battery anode end and a manufacturing method thereof, and the sealing structure comprises a battery shell with a closed lower end and an open upper end and a current collector with a sealed closed opening, wherein a through hole is formed in the current collector, an anode cap for closing the through hole is arranged at the top of the current collector, the bottom of the current collector is welded with an anode lug to form electric conduction, the hole wall of the through hole in the current collector is mainly extended upwards all the time, the top of the hole wall can be turned inwards to form a turned edge to be coated on the top of a valve body, and then the anode cap is covered with the turned edge to close the through hole, so that the anode cap can directly form electric conduction output with the current collector, and the trouble that the; therefore, the improved positive terminal sealing structure is simpler in design and simplified in installation process, and has the advantages of good conductive connection reliability, high conductive efficiency, safe use and the like by combining a corresponding manufacturing method.)

1. The utility model provides a lithium cell positive terminal sealing structure, includes that the lower extreme seals, upper end open-ended battery case (1) and sealed the open-ended current collector (2), mesopore (7) that link up about being equipped with in this current collector, installation valve body (3) in the mesopore, current collector (2) top is equipped with positive cap (4) of sealing mesopore (7), and positive utmost point ear is connected in current collector (2) bottom electrically conductive, its characterized in that current collector (2) mesopore (7) hole wall that has upwards extension, this pore wall top is equipped with turn-up (211) of the cladding at valve body (3) top of turning over to the enstrophe, positive cap (4) lid close turn-up (211) and seal mesopore (7).

2. The sealing structure of the positive electrode terminal of the lithium battery as claimed in claim 1, wherein the positive electrode cap (4) is formed by an upper small cylinder (41) and a lower large cylinder (42), the large cylinder (41) covers the turned edge (211) and closes the middle hole (7), and the outer circumferential surface of the small cylinder (42) is provided with a plurality of pressure relief holes (43), each pressure relief hole is communicated with the inside of the valve body (3).

3. The sealing structure of the positive electrode terminal of the lithium battery according to claim 1, wherein the current collector (2) is composed of a current collecting piece (21) arranged in the opening, an outer sealing ring (23) hermetically arranged between the current collecting piece and the battery shell (1), and an inner sealing ring (22) hermetically arranged between the current collecting piece (21) and the valve body (3), and the top surface of the current collecting piece (21) is provided with the plastic cover (6).

4. The sealing structure of the positive electrode terminal of the lithium battery as claimed in claim 3, wherein the valve body (3) is formed by an upper cylinder (31) having a larger outer diameter and a lower cylinder (32) having a smaller outer diameter.

5. The sealing structure of the positive electrode terminal of the lithium battery as claimed in claim 4, wherein the current collecting plate (21) is a conductive wafer, a secondary step shaft formed by bending and extending upwards is arranged at the center of the conductive wafer, the central hole (7) is vertically through along the axial lead of the secondary step shaft, and the axial lead of the central hole (7) is overlapped with the axial lead of the battery shell (1).

6. The sealing structure of the positive electrode end of the lithium battery according to claim 5, wherein the middle hole (7) is a stepped hole formed by connecting a small hole (71) at the upper part and a large hole (72) at the lower part, the upper cylinder (31) of the valve body (3) is embedded and fixed in the small hole (71), and the lower cylinder (32) of the valve body (3) is embedded and fixed in the large hole (72) through the inner sealing ring (22).

7. The sealing structure of the positive electrode terminal of the lithium battery as claimed in claim 1, wherein the battery case (1) is provided with a rolling groove (11) on the outer circumferential surface thereof, and the current collector (2) is inserted through the opening and is disposed on the rolling groove (11).

8. The sealing structure of the positive electrode terminal of the lithium battery according to claim 1, wherein the battery case (1) is internally provided with an insulating ring (5) which is arranged below the rolling groove (11) and pressed by the rolling groove.

9. The sealing structure of the positive electrode terminal of the lithium battery as claimed in claim 1, wherein the inner sealing ring (22) is cylindrical, and a plurality of grooves (221) extending through in the diameter direction are respectively formed on the circular top plane and the circular bottom plane of the inner sealing ring, and each groove (221) on the top plane and the circular bottom plane are arranged in a staggered manner.

10. The method for manufacturing the sealing structure of the positive electrode terminal of the lithium battery as claimed in any one of claims 1 to 9, wherein the manufacturing method comprises the steps of:

step one, covering an insulating ring (5) on a positive electrode lug of a battery core in a battery shell (1);

step two, arranging a rolling groove (11) on the outer circumferential surface of the battery shell (1) above the insulating ring (5) to enable the rolling groove to press the insulating ring (5);

step three, assembling the current collecting piece (21), the inner sealing ring (22) and the outer sealing ring (23) together to form an independent part of the current collector (2) for standby;

step four, the current collector (2) is arranged on the rolling groove (11) after being arranged from the opening at the top of the battery shell (1), and sealing is formed between the outer sealing ring (23) and the battery shell (1);

step five, pressurizing the current collector (2) to contact with the positive electrode tab, and welding to form conductive connection firmly;

sixthly, mounting the plastic cover (6) above the current collector (2), and curling the opening part of the battery shell (1) inwards to press the plastic cover (6);

step seven, baking the lithium battery manufactured in the step six, and drying the water in the battery cell;

step eight, injecting electrolyte into the battery cell;

step nine, the valve body (3) is arranged in the middle hole (7) of the current collector (2) until the lower cylinder (32) of the valve body (3) and the inner sealing ring (22) form sealing;

step ten, extending the hole wall of the middle hole (7) of the current collector (2) upwards, and then turning and curling inwards to form a curled edge (211) to cover the top of the valve body (3) and fix the valve body firmly;

step eleven, covering the turned edge (211) with the positive electrode cap (4) with the pressure relief hole (43) and sealing the middle hole (7) to finish the manufacture of the sealing structure of the positive electrode end of the lithium battery.

Technical Field

The invention relates to a sealing structure, in particular to a sealing structure of a lithium battery anode end and a manufacturing method thereof.

Background

At present, the sealing structure of the positive pole end can be involved in the production process of the lithium battery with no electrode lugs, the sealing structure mainly comprises a battery shell, a current collector, a middle hole, a valve body, a positive pole cap and the like, the bottom of the current collector is conductively connected with a positive pole lug, the positive pole cap is arranged at the top of the current collector and seals the middle hole, the top of the valve body extends upwards to exceed the top of the current collector and covers the positive pole cap at the top of the valve body, so that the positive pole cap is firstly conductive with the valve body in the conductive process, and then the current can be output by conducting through the valve body and the current collector.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a lithium battery positive electrode end sealing structure and a manufacturing method thereof, wherein the structure is simple in design, the installation procedure is simplified, the conductive connection reliability is good, the conductive efficiency is high, and the use is safe.

The technical problem of the invention is realized by the following technical scheme:

the utility model provides a lithium cell positive terminal sealing structure, includes that the lower extreme seals, upper end open-ended battery case and seal open-ended current collector is equipped with the mesopore that link up from top to bottom in this current collector, installs the valve body in the mesopore, and the current collector top is equipped with the anodal cap that seals the mesopore, and the anodal utmost point ear is connected in the current collector bottom is electrically conductive, the current collector mesopore have the pore wall that upwards extends, this pore wall top is equipped with the turn-up of the cladding at the valve body top of turning over to the enstrophe, anodal.

The positive electrode cap is composed of a small cylinder at the upper part and a large cylinder at the lower part, the large cylinder covers the turned edge and seals the middle hole, the outer circumference of the small cylinder is provided with a plurality of pressure relief holes, and each pressure relief hole is communicated with the inside of the valve body.

The current collector is composed of a current collecting piece arranged in the opening, an outer sealing ring arranged between the current collecting piece and the battery shell in a sealing mode, and an inner sealing ring arranged between the current collecting piece and the valve body in a sealing mode, and a plastic cover is arranged on the top face of the current collecting piece.

The valve body is composed of an upper cylinder with a larger outer diameter and a lower cylinder with a smaller outer diameter.

The current collecting piece is a conductive wafer, a secondary step shaft which is formed by extending and bending the connected body upwards is arranged at the circle center of the conductive wafer, the middle hole is communicated up and down along the axial lead of the secondary step shaft, and the axial lead of the middle hole is overlapped with the axial lead of the battery shell.

The middle hole is a stepped hole formed by connecting a small hole at the upper part with a large hole at the lower part, the upper cylinder of the valve body is embedded and fixed in the small hole, and the lower cylinder of the valve body is embedded and fixed in the large hole through an inner sealing ring.

The outer circumference of the battery shell is provided with a rolling groove, and the current collector is arranged in the rolling groove from the opening.

An insulating ring which is arranged below the rolling groove and pressed by the rolling groove is arranged in the battery shell.

The inner sealing ring is cylindrical, a plurality of grooves which extend through along the diameter direction are respectively arranged on the circular top plane and the circular bottom plane of the inner sealing ring, and each groove on the top plane and the circular bottom plane is arranged in a staggered mode.

A manufacturing method of a sealing structure of a positive electrode end of a lithium battery comprises the following steps:

covering an insulating ring on a positive electrode lug of a battery cell in a battery shell;

step two, arranging a rolling groove on the outer circumferential surface of the battery shell above the insulating ring, and enabling the rolling groove to press the insulating ring;

step three, assembling the current collecting piece, the inner sealing ring and the outer sealing ring together to form an independent part of a current collector for standby;

step four, the current collector is arranged on the rolling groove after being arranged from the opening at the top of the battery shell, and sealing is formed between the outer sealing ring and the battery shell;

step five, pressurizing the current collector to contact with the positive electrode tab, and firmly welding to form conductive connection;

step six, mounting the plastic cover above the current collector, and curling the opening part of the battery shell inwards to press the plastic cover;

step seven, baking the lithium battery manufactured in the step six, and drying the water in the battery cell;

step eight, injecting electrolyte into the battery cell;

step nine, the valve body is arranged in the middle hole of the current collector until the lower cylinder of the valve body and the inner sealing ring form sealing;

step ten, extending the hole wall of the middle hole of the current collector upwards, turning the hole wall inwards, curling the hole edge, covering the top of the valve body, and fixing the hole wall firmly;

step eleven, the positive pole cap with the pressure relief hole is covered on the turned edge and the middle hole is sealed, and the manufacturing of the sealing structure of the positive pole end of the lithium battery is completed.

Compared with the prior art, the invention mainly extends the hole wall of the hole in the current collector upwards, enables the top of the hole wall to be turned inwards to form a turned edge to be coated on the top of the valve body, and then covers the turned edge of the positive electrode cap to seal the hole, so that the positive electrode cap can directly form conductive output with the current collector, and avoids the trouble that current is indirectly output through the valve body in the traditional structure; therefore, the improved positive terminal sealing structure is simpler in design and simplified in installation procedures, so that the improved positive terminal sealing structure has the advantages of being good in conductive connection reliability, high in conductive efficiency, safe to use and the like.

Drawings

Fig. 1 is a schematic sectional structure of the present invention.

Fig. 2 is a schematic sectional structure view of the positive electrode cap.

Fig. 3 is a schematic sectional view of the structure of the current collector at the center hole.

Fig. 4 is a schematic sectional structure view of the valve body.

Fig. 5 is an enlarged sectional structural view of the inner seal ring.

Fig. 6 is a top view of fig. 5.

Detailed Description

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

As shown in fig. 1 to 6, 1 is a battery case, 11 is a rolling groove, 2 is a current collector, 21 is a current collecting piece, 211 is a turned edge, 22 is an inner sealing ring, 221 is a groove, 23 is an outer sealing ring, 3 is a valve body, 31 is an upper cylinder, 32 is a lower cylinder, 4 is a positive electrode cap, 41 is a small cylinder, 42 is a large cylinder, 43 is a pressure relief hole, 5 is an insulating ring, 6 is a plastic cover, 7 is a middle hole, 71 is a small hole, and 72 is a large hole.

A lithium battery positive pole end sealing structure and its manufacturing method, as shown in figure 1, mainly relate to an improvement of the positive pole end sealing structure of the lithium battery, it includes the bottom end is closed, open-ended battery casing 1 and seals the open-ended current collector 2, there is up and down through mesopore 7 in the current collector, there is positive cap 4 to close mesopore 7 in the top of the current collector 2, the bottom of the current collector 2 and positive pole lug weld and form and conduct electricity.

The battery case 1 is mainly used for installing a battery core and filling electrolyte, and the current collector 2 is composed of a current collecting piece 21 arranged in the opening, an outer sealing ring 23 arranged between the current collecting piece and the battery case 1 in a sealing mode, and an inner sealing ring 22 arranged between the current collecting piece 21 and the valve body 3 in a sealing mode.

The inner seal ring 22 is cylindrical, a plurality of grooves 221 extending through in the diameter direction are respectively arranged on the circular top plane and the circular bottom plane of the inner seal ring, for example, 1-50 grooves can be designed on each plane, each groove 221 on the top plane and the circular bottom plane needs to be arranged according to mutual dislocation, specifically, the grooves are arranged in the grooves 221 on the two planes, one groove 221 on any two planes is optionally checked, the two grooves 221 are exactly vertical or crossed with each other in the spatial position, but cannot be in a parallel state, and the purpose is to ensure that the use thickness of the inner seal ring 22 is not affected.

And design recess 221 on the bottom plane is mainly for making things convenient for electrolyte can pass through the more smooth and easy injection electric core of recess 221, all sets up recess 221 on top plane and the bottom plane and can solve the problem that interior sealing washer 22 placed the direction, also be exactly regardless of which planar direction of packing into interior sealing washer 22 down, can both use recess 221 to annotate the liquid to make things convenient for the intelligent quick production of lithium cell.

The top surface of the current collecting piece 21 is provided with a plastic cover 6, the current collecting piece 21 is a conductive wafer, a secondary step shaft which is formed by extending upwards and bending the plastic cover 6 is arranged at the center of the conductive wafer, a middle hole 7 is vertically communicated along the axial lead of the secondary step shaft, and the axial lead of the middle hole is overlapped with the axial lead of the battery shell 1.

Meanwhile, due to the bending structure of the secondary step shaft, the middle hole 7 also forms a step hole formed by connecting a small hole 71 at the upper part with a large hole 72 at the lower part, the valve body 3 is installed in the middle hole 7, the valve body is formed by an upper cylinder 31 with a larger outer diameter and a lower cylinder 32 with a smaller outer diameter, and belongs to the shell structure of a battery safety valve, so that when the internal pressure of a battery is overlarge, the pressure can be relieved through the safety valve.

The specific assembly structure of the valve body 3 in the central hole 4 is therefore: the upper cylinder 31 of the valve body 3 is embedded and fixed in the small hole 71 of the middle hole 7, namely the valve body 3 is directly contacted with the current collecting piece 21 to form electric conduction between the two, and the lower cylinder 32 of the valve body 3 is embedded and fixed in the large hole 72 of the middle hole 7 through the inner sealing ring 22.

The central hole 7 in the current collector 2, that is, the central hole 7 in the current collector 21, has an upwardly extending hole wall, the top of the hole wall is higher than the top of the valve body 3, and then the hole wall has a turned edge 211 folded inwards to cover the top of the valve body 3, and the positive electrode cap 4 covers the turned edge 211 and closes the central hole 7.

The positive electrode cap 4 is composed of a small cylinder 41 at the upper part and a large cylinder 42 at the lower part, the large cylinder 42 covers the turned edge 211 and seals the middle hole 7, the practical structure is that a circle of inner shoulder is formed in the positive electrode cap 4 due to the special structures of the small cylinder 41 and the large cylinder 42, the fixed turned edge 211 is pressed through the inner shoulder, a plurality of pressure relief holes 43 are arranged on the outer circumferential surface of the small cylinder 41, each pressure relief hole is communicated with the valve body 3, and the positive electrode cap can be used for assisting a safety valve to relieve pressure in the battery shell 1 and plays a role in safety protection.

Obviously, the positive electrode cap 4 with the structure can directly form conductive output with the current collector 2, and avoids the trouble that current is indirectly conducted and output through the valve body 3 in the traditional sealing structure, so that the improved positive electrode end sealing structure is simpler in design and simplified in installation procedures, and has the advantages of good conductive connection reliability, high conductive efficiency, safe use and the like.

In addition, the battery case 1 is provided with a rolling groove 11 on the outer circumferential surface, and the current collector 2 formed by independently assembling the current collecting piece 21, the inner seal ring 22 and the outer seal ring 23 is installed on the rolling groove 11 after being installed from the opening, that is, the installation position of the current collector 2 in the opening is positioned by the rolling groove 11, and the battery case 1 is also provided with an insulating ring 5 which is installed below the rolling groove 11 and pressed by the rolling groove.

The manufacturing method of the sealing structure of the positive electrode end of the lithium battery mainly comprises the following steps:

firstly, covering an insulating ring 5 on a positive electrode lug of a battery core in a battery shell 1;

step two, arranging a rolling groove 11 on the outer circumferential surface of the battery shell 1 above the insulating ring 5, and enabling the rolling groove to press the insulating ring 5;

step three, assembling the current collecting piece 21, the inner sealing ring 22 and the outer sealing ring 23 together to form an independent part of the current collector 2 for standby;

step four, the current collector 2 is arranged on the roller groove 11 after being arranged from the opening at the top of the battery shell 1, and sealing is formed between the outer sealing ring 23 and the battery shell 1;

step five, pressurizing the current collector 2 to contact with the positive electrode tab, and welding to form conductive connection firmly;

sixthly, mounting the plastic cover 6 above the current collector 2, and curling the opening part of the battery shell 1 inwards to press the plastic cover 6;

step seven, baking the lithium battery manufactured in the step six, and drying the water in the battery cell;

step eight, injecting electrolyte into the battery cell;

step nine, the valve body 3 is arranged in the middle hole 7 of the current collector 2 until the lower cylinder 32 of the valve body 3 and the inner sealing ring 22 form a seal;

step ten, extending the hole wall of the middle hole 7 of the current collector 2 upwards, and then folding the turned edge 211 inwards to cover the top of the valve body 3 and fix the turned edge firmly;

step eleven, covering the turned edge 211 with the positive electrode cap 4 with the pressure relief hole 43, and sealing the middle hole 7 to complete the manufacture of the sealing structure of the positive electrode end of the lithium battery.

The above description is only a specific embodiment of the present invention, and those skilled in the art should understand that any similar structural design to the embodiment is included in the protection scope of the present invention.