WO2022206866A1

WO2022206866A1 - Battery

Info

Publication number: WO2022206866A1
Application number: PCT/CN2022/084219
Authority: WO
Inventors: 卫志达; 彭宁; 谢斌; 徐延铭
Original assignee: 珠海冠宇电池股份有限公司
Priority date: 2021-03-31
Filing date: 2022-03-30
Publication date: 2022-10-06
Also published as: CN113097661A

Abstract

Provided is a battery, which comprises a conductive housing, a top cover, and a battery cell; the conductive housing and the top cover are connected in an insulated manner and enclosingly form a cavity, the battery cell is located within the cavity, the top cover has a conductive member, the battery cell comprises an electrode tab welded to the conductive member, and a surface of the conductive member away from the electrode tab has a first welding mark formed via the welding. A welding mark is formed on the surface of the conductive member away from the electrode tab, which can effectively prevent thes problem of false welding, the sealing performance of the battery is improved, and fulfillment of a function thereof is facilitated.

Description

Battery

technical field

The present invention relates to a battery.

Background technique

A battery generally includes a casing and a battery cell placed in the casing. The battery core has a positive electrode lug connected to the positive electrode module (composed of positive electrode sheets) and a negative electrode lug connected to the negative electrode module (composed of negative electrode sheets). (or connecting pieces) are respectively connected with the positive and negative electrodes to form the positive and negative electrodes of the battery respectively to realize the manufacture of the battery. Generally, the tabs and the conductive parts can be welded together, but in the conventional battery structure, there is a problem of virtual welding (that is, some areas are not welded together) between the welding parts of the tabs and the conductive parts, and the virtual welding problem cannot usually be detected. Due to the existence of the virtual welding problem, the sealing performance of the battery is not good, which affects the function of the battery, and also has certain safety risks.

SUMMARY OF THE INVENTION

The present invention provides a battery to at least solve the problem of virtual welding existing between the tabs and the conductive member in the battery structure in the above-mentioned prior art, and the resulting defects such as poor battery sealing.

In one aspect of the present invention, a battery is provided, which includes a conductive shell, a top cover and a battery cell. The conductive shell and the top cover are insulated and connected to form a cavity. The battery core is located in the cavity. The top cover includes a conductive member. The core includes tabs welded together with the conductive member, and the surface of the conductive member remote from the tab has a first solder print formed by the welding.

According to some embodiments of the present invention, the width of the first solder print is 0.1 mm-1.6 mm; and/or the height of the solder print is 0.05 mm-0.8 mm based on the surface of the conductive member away from the tab.

According to some embodiments of the present invention, the side of the tab away from the conductive member has a second solder print formed by the above-mentioned welding, and the width of the second solder print is greater than that of the first solder print.

According to some embodiments of the present invention, the top cover further includes a connecting member, the conductive member has a first portion and a second portion surrounding the first portion; the conductive housing is connected with the connecting member, and the connecting member and the second portion are connected by an insulating sealing member, so as to The insulating connection between the conductive shell and the top cover is realized; the first part is welded with the tab to realize the welding of the conductive part and the tab; within the area.

According to some embodiments of the present invention, in the direction from the first solder print to the through hole, the distance from the first solder print to the through hole is greater than or equal to 0.5 mm; and/or, the distance from the first solder print to the insulating seal greater than 1.5mm.

According to some embodiments of the present invention, the connector and the tab are located below the conductive member, the side of the tab away from the conductive member has a second solder print formed by the above welding, and the part of the second solder print farthest from the conductive member is located on the connector Underneath the side away from the conductor.

According to some embodiments of the present invention, the through holes are filled with insulating fillers, and the insulating fillers include polymer materials and/or inorganic materials.

According to some embodiments of the present invention, the insulating seal is made of rubber; and/or the thickness of the insulating seal is 0.03mm-0.15mm.

According to some embodiments of the present invention, the tabs are positive tabs, the battery cell further includes a negative tab, and the negative tab is connected to the conductive housing.

According to some embodiments of the present invention, the tabs are negative tabs, and the battery cell further includes a positive tab connected to the conductive housing.

The implementation of the present invention has at least the following beneficial effects:

In the battery provided by the invention, a welding mark is formed on the surface of the conductive member away from the tab, which can effectively avoid the problem of virtual welding, improve the sealing performance of the battery, and facilitate its function; The setting position of each component (that is, positioning according to the solder print) is more conducive to the manufacture of the battery.

Description of drawings

1 and 2 are respectively sectional views of different positions of the battery structure in an embodiment of the present invention (FIG. 1 shows the positive electrode tab, and FIG. 2 shows the negative electrode tab);

3 is a top view of a top cover covering the conductive casing according to an embodiment of the present invention.

Description of reference numbers:

1: Conductive shell; 2: Conductive parts: 3: Cells; 4: Cavity; 5: Connectors; 6: Insulation seals; 7: Insulation parts; 21: The first solder mark; 21': The second solder 22: through-hole; 31: negative tab; 32: positive tab; 33: positive tab; 34: diaphragm; 35: negative tab; H: height of the first solder print; W ₁ : width of the first solder print; W ₂ : The distance from the first solder print to the through hole.

Detailed ways

In order to make those skilled in the art better understand the solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings. The specific embodiments listed below are only to describe the principles and features of the present invention, and the examples are only used to explain the present invention, and do not limit the scope of the present invention. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention. Hereinafter, the tabs welded with the conductive member 2 are used as positive tabs (positive tabs) as an example for description, but the present invention is not limited thereto.

As shown in FIG. 1 to FIG. 3 , a battery according to an embodiment of the present invention includes a conductive casing 1 , a top cover and a cell 3 . The conductive casing 1 and the top cover are insulated and connected to form a cavity 4 , and the cell 3 is located in the Inside the cavity 4 , the top cover includes the conductive member 2 , the battery core 3 includes a positive electrode lug 32 welded with the conductive member 2 , and the surface of the conductive member 2 away from the positive electrode lug 32 has a first solder mark 21 formed by the welding.

Welding marks are marks caused by welding, that is, after welding, compared with the unwelded parts, the welded parts have a significantly different shape, such as different colors, or the formation of bulges. In specific implementation, conditions such as welding strength can be adjusted so that after the conductive member 2 and the positive electrode lug 32 are welded together, a first welding mark 21 is formed on the surface of the conductive member 2 away from the positive electrode lug 32, and the welding can be monitored through the first welding mark 21. effect, to avoid problems such as virtual welding. The welding method may include laser welding.

In some embodiments, the width W1 of the _first solder print 21 is 0.1mm-1.6mm, such as 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, The range of 1mm, 1.2mm, 1.4mm, 1.6mm or any two of these values is conducive to monitoring the welding effect, avoiding the problem of false welding, and further ensuring the function of the battery.

Further, based on the surface of the conductive member 2 away from the positive electrode lug 32, the height H of the first solder print 21 is 0.05mm-0.8mm, such as 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, The range of 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm or any two of these values is beneficial to further ensure the distance between the conductive member 2 and the positive electrode lug 32 High welding strength, avoiding the problem of virtual welding, and simplifying the manufacturing process of the battery. Specifically, the first solder mark 21 is a protrusion formed on the surface of the conductive member 2 away from the positive electrode lug 32 caused by the above welding, and the maximum vertical distance from the protrusion to the surface of the conductive member 2 away from the positive electrode lug 32 is The height H of the first solder print 21 .

Under normal circumstances, the welding mark penetrates the welding part formed by the above-mentioned welding between the positive electrode lug 32 and the conductive member 2 , that is, there is a second welding mark 21 ′ formed by the above welding on the side of the positive electrode lug 32 away from the conductive member 2 . The seal 21 ′ is, for example, a protrusion formed on the side of the positive electrode lug 32 away from the conductive member 2, and so on. During specific implementation, after the positive electrode lug 32 and the conductive member 2 are stacked, they can be welded from one side of the positive electrode lug 32 to form The width of the second solder print 21 ′ is generally larger than the width of the first solder print 21 , which is beneficial to further improve the welding strength between the positive electrode lug 32 and the conductive member 2 and avoid the problem of virtual welding.

In some embodiments, the top cover further includes a connecting member 5, the conductive member 2 has a first part and a second part surrounding the first part; the conductive housing 1 is connected with the connecting member 5, and the connecting member 5 and the second part pass through an insulating sealing member 6 is connected to realize the insulating connection between the conductive shell 1 and the top cover; the first part is welded with the positive electrode lug 32 to realize the welding of the conductive part 2 and the positive electrode lug 32, that is, the first welding mark 21 exists in the first part. Part of the side away from the positive electrode tab 32, this structure is beneficial to improve the overall sealing performance of the battery (FIG. 3 is a schematic diagram of the top cover structure on the side where the conductive member 2 is located). Wherein, the conductive housing 1 is connected to one end of the connecting member 5 away from the conductive member 2, and the connection method is, for example, welding.

Specifically, the first part of the conductive member 2 has a through hole 22, and the through hole 22 is located in the area surrounded by the first solder print 21, that is, the through hole 22 is sealed by the positive electrode lug 32 welded with the conductive member 2 ( 1 and FIG. 2 ), that is, by welding the conductive member 2 and the positive electrode tab 32 together, the conductive member 2 and the positive electrode tab 32 can be connected and sealed at the same time.

The through hole 22 can be used as a positioning hole in the battery manufacturing process, that is, during the battery manufacturing process, the orientation of each component can be judged/adjusted through the through hole 22. For example, in the battery manufacturing process, the conductive parts 2 , After the sealing insulating member 6 and the connecting member 5 are stacked and arranged, press-fit/composite processing is performed to obtain the top cover. During this process, the placement position of the connecting member 5 and the sealing insulating member can be adjusted through the through hole 22, which is more conducive to The production of the top cover, and the performance of making the produced top cover have good sealing performance; for another example, when the surface degreasing and other treatments are performed on the conductive parts 2, it is usually carried out in batches (that is, multiple conductive parts 2 are carried out at the same time at the same time. Surface degreasing, etc.) to ensure the consistency of the surface treatment of the conductive parts. In this process, each conductive part can be separated by through holes (or positioning holes) 22, which is convenient for operation; for another example, when doing PACK welding wires or When the conductive sheet is used, it can be positioned through the through hole 22, and the solder mark formed by PACK welding can be controlled between the first solder mark 21 and the through hole 22, which can reduce the risk of battery leakage caused by welding through the conductive member 2 during PACK welding ( Under the battery structure system of the present invention, even if the PACK is welded through the conductive member 2, it will still be blocked by the positive electrode lug 32, so as to avoid battery leakage). Therefore, the arrangement of the through holes 22 is beneficial to further improve the battery performance and manufacturing efficiency.

In some embodiments, the through hole 22 , the area surrounded by the first solder print 21 , and the conductive member 2 are arranged concentrically, that is, the area surrounded by the through hole 22 , the first solder print 21 , and the center of the conductive member 2 On the same axis, for example, the cross-section of the through hole 22, the cross-section of the area surrounded by the first solder print 21, and the cross-section of the conductive member 2 are substantially circular, and the center of the circle is on the same axis (eg 3), it is more conducive to play its role as a positioning hole and improve the production yield of the battery and the performance of the battery.

In some preferred embodiments, in the direction from the first solder print 21 to the through hole 22, the distance W ₂ from the first solder print 21 to the through hole 22 is greater than or equal to 0.5mm, such as 0.5mm, 0.8mm, 1mm , 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm or a range of any two of these values. For example, the cross section of the area surrounded by the first solder print 21 and the cross section of the through hole 22 are substantially circular (as shown in FIG. 3 ). The radius of the cross section is d1, the radius of the cross section of the through hole 22 is d2, and the distance from the first solder print 21 to the through hole 22 is the difference between d1 and d2 (ie, W ₂ =d1-d2).

Further, the distance from the first solder print 21 to the insulating seal 6 is greater than 1.5 mm, for example, a range of 1.6 mm, 1.8 mm, 2 mm, 2.2 mm, 2.5 mm or any two thereof.

As mentioned above, the side of the positive electrode lug 32 away from the conductive member 2 may have the second welding mark 21 ′ formed by the above welding. In some embodiments, the connecting member 5 and the positive electrode lug 32 are located under the conductive member 2 , and the second welding The part of the print 21' farthest from the conductive member 2 is located below the side of the connector 5 away from the conductive member 2, that is, the height of the solder print on the surface of the positive electrode lug 32 (the second solder print 21') is lower than the inner surface of the connector 5 (connection). part 5 away from the side of the conductive part 2).

In some embodiments, the through holes 22 are filled with insulating fillers, which is beneficial to further ensure the sealing of the battery and avoid problems such as liquid leakage. The insulating filler may include polymer materials and/or inorganic materials, such as AB glue, etc., but is not limited thereto.

In some embodiments, the thickness of the positive tab 32 is 0.04mm-1mm, such as 0.04mm, 0.06mm, 0.08mm, 0.1mm, 0.3mm, 0.5mm, 0.8mm, 1mm, or any two of these values. The range is favorable for the formation of a solder mark after the positive electrode lug 32 and the conductive member 2 are welded, and the function of the battery is ensured.

Optionally, the material of the positive electrode lug 32 may be aluminum, but not limited thereto, and may also be other conventional positive electrode lug materials.

Further, the thickness of the conductive member 2 may be 0.06mm-0.5mm, such as 0.06mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm or any of these values A range of any two of them.

Optionally, the material of the conductive member may be aluminum alloy or double-layer aluminum-nickel composite material, but is not limited thereto, and may also be other conductive materials.

In some embodiments, the insulating seal 6 is made of rubber, which may be conventional insulating sealants.

In some embodiments, the thickness of the insulating seal 6 may generally be 0.03mm-0.15mm, such as a range of 0.03mm, 0.05mm, 0.08mm, 0.1mm, 0.13mm, 0.15mm, or any two of these values , which is beneficial to the sealing performance of the battery.

The above-mentioned connector 5 can be a conventional conductive element in the art, and its material is, for example, nickel, stainless steel, stainless steel, nickel-plated, etc. In some embodiments, the thickness of the connector 5 is 0.1mm-0.3mm, such as 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, or a range of any two of these values.

In some embodiments, the thickness of the conductive shell 1 can be 0.1mm-0.3mm, such as 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm or a range composed of any two of these values. Optionally, the material of the conductive housing 1 is stainless steel, for example, but not limited thereto.

The battery cell 3 also includes a negative electrode lug 31 connected to the conductive casing 1. In some embodiments, the connection between the negative electrode lug 31 and the conductive casing 1 is welding, and the negative electrode lug 31 may be welded to the conductive casing 1. In the middle of the bottom surface, the welding method is, for example, resistance welding or the like.

Specifically, the battery cell 3 includes a positive electrode sheet 33 , a negative electrode sheet 35 , a separator 35 separating the positive electrode sheet 33 and the negative electrode sheet 34 , which may be formed by winding the positive electrode sheet 33 , the separator 34 , and the negative electrode sheet 35 after being stacked in sequence. A rolled structure or a laminated structure formed by lamination, but not limited thereto, other conventional structures may also be used.

Under normal circumstances, both the end of the cell 3 close to the conductive member 2 and the end far from the conductive member 2 are provided with an insulating member 7 (end face insulating member), wherein a layer of insulation can also be attached to the surface of the positive electrode lug 32 away from the conductive member 2 A piece (flat sheet insulating piece) is used to replace the insulating piece at one end of the cell close to the conductive piece 2 . Optionally, the insulating member may include insulating glue.

The above-mentioned battery also includes an electrolyte, which may be a conventional electrolyte in the art, which is not particularly limited in the present invention, and will not be repeated here.

The battery of the present invention can be a button-type battery, such as a button-type polymer lithium ion battery, etc. Through the structural design of the present invention, the problem of virtual welding between the tab and the conductive member can be effectively improved, thereby improving the sealing performance of the battery and the like. , which is conducive to its function.

The battery of the present invention can be produced according to conventional methods in the art. In some preferred embodiments, the production process of the above-mentioned battery can include:

(1) Connect the second part of the conductive member 2 through the insulating sealing member 6 and the connecting member 5 by hot pressing or the like to form a top cover; wherein, a through hole (or a central hole is provided in the middle of the conductive member 2) ) 22, judging/adjusting the orientation of each component in the process of hot-pressing shaping according to the through hole.

(2) Put the cell 3 into the cavity surrounded by the conductive shell 1, and weld the negative lug 31 of the cell to the middle of the bottom surface of the conductive shell 1;

(3) Weld the first part of the conductive member 2 on the top cover and the positive electrode lug 32 of the battery cell 3 together, and make the surface of the conductive member 2 away from the positive electrode lug 32 to have the first welding mark 21 and the positive electrode lug formed by the welding. 32 The surface away from the conductive member 2 has a second solder mark 21' formed by the welding, and satisfies the concentric arrangement of the area surrounded by the first solder mark 21, the through hole 22, and the conductive member 2;

(4) baking the semi-finished battery obtained in step (3), and then injecting electrolyte into it, and then welding the connector 5 on the top cover and the conductive shell 1 together to complete the cover; according to The through hole 22 needs to be filled with insulating fillers (or not filled), and then packaged with an outer package (polyvinyl chloride (PVC, etc.)) to obtain a battery.

In the above embodiment, the tab welded with the conductive member 2 is the positive tab, but the present invention is not limited to the above-mentioned embodiment, and in another embodiment, the tab welded with the conductive member 2 may also be It is a negative pole ear (negative pole), that is, the negative pole and the conductive member 2 are welded together and a welding mark is formed on the side of the conductive component 2 away from the negative pole, and the positive pole is connected with the conductive shell, except that the above-mentioned positive pole 32 is connected to the negative pole Except for the replacement of the position of the ear 31 , other components and the positional relationship between the components and other conditions, principles and effects can be explained by referring to the above-mentioned embodiments, and details will not be repeated here.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

A battery is characterized in that it comprises a conductive shell, a top cover and a battery cell, the conductive shell is insulated from the top cover and is connected to a cavity, and the battery core is located in the cavity, and the battery core is located in the cavity. The top cover includes a conductive member, the battery core includes a tab welded with the conductive member, and a surface of the conductive member away from the tab has a first solder print formed by the welding.
The battery according to claim 1, wherein the width of the first solder print is 0.1 mm-1.6 mm; and/or, based on the surface of the conductive member far from the tab, the solder The height of the print is 0.05mm-0.8mm.
The battery according to claim 1, wherein a side of the tab away from the conductive member has a second welding mark formed by the welding, and the width of the second welding mark is larger than that of the first welding mark. print width.
The battery according to any one of claims 1-3, characterized in that,

The top cover further includes a connector having a first portion and a second portion surrounding the first portion;

the conductive housing is connected with the connecting piece, and the connecting piece and the second part are connected by an insulating seal, so as to realize the insulating connection between the conductive housing and the top cover;

the first part and the tab are welded together, so as to realize the welding of the conductive member and the tab;

The first portion has a through hole located in an area surrounded by the first solder print.
The battery of claim 4, wherein, in a direction from the first solder print to the through hole, a distance from the first solder print to the through hole is greater than or equal to 0.5 mm; and /or, the distance from the first solder print to the insulating seal is greater than 1.5 mm.
The battery according to claim 4, wherein the connecting member and the tab are located below the conductive member, and a side of the tab away from the conductive member has a second electrode formed by the welding. Soldering, the part of the second soldering that is farthest from the conductive member is located below the side of the connecting member that is far from the conductive member.
The battery according to claim 4, wherein the through holes are filled with insulating fillers, and the insulating fillers include polymer materials and/or inorganic materials.
The battery according to claim 4, wherein the insulating sealing member is made of rubber; and/or the thickness of the insulating sealing member is 0.03mm-0.15mm.
The battery according to any one of claims 1-3, wherein the tab is a positive tab, the battery cell further comprises a negative tab, and the negative tab is connected to the conductive shell.
The battery according to any one of claims 1-3, wherein the tab is a negative tab, and the battery cell further comprises a positive tab connected to the conductive shell.