Battery

Abstract

The utility model discloses a battery which comprises a shell, a cover plate, a pole and a battery cell, the shell is provided with an opening, the cover plate is covered on the opening, a through hole is arranged on the cover plate, and the pole is arranged in the through hole. The battery cell comprises a battery cell main body and a pole lug, the battery cell main body is arranged in the shell, the pole lug comprises a first connecting part, a fusing part and a second connecting part which are connected in sequence, the sectional area of the first connecting part and the sectional area of the second connecting part are both larger than that of the fusing part, the first connecting part is connected with the battery cell main body, and the second connecting part is connected with the end, located in the shell, of the pole column. The tab comprises a plurality of tab pieces which are stacked together, each tab piece comprises a first sub-connecting part, a sub-fusing part and a second sub-connecting part which are connected in sequence, the first sub-connecting parts of the tabs are stacked together to form a first connecting part, the second sub-connecting parts of the tabs are stacked together to form a second connecting part, and the sub-fusing parts of the tabs are welded together to form a fusing part; and a first welding mark is formed on the side surface of the tab. According to the utility model, the safety of the battery can be ensured.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially relates to a battery. BACKGROUND

[0002] At present, since lithium ion power battery realizes commercialization, it is rapidly widely used in various electric equipment because of many advantages such as light weight, high voltage, small size, no memory effect, high specific energy, long cycle life and environmental friendliness.

[0003] In order to ensure the safety of the battery, the conventional battery will be provided with a fuse part at the tab, when short circuit, the short circuit current is greater than the fuse current of the fuse part, so that the fuse part is fused, and the connection with the battery cell is cut off.

[0004] However, for the winding type battery cell, the pole piece extends out of multiple tab pieces, the multiple tab pieces are overlapped to form a tab, the tab piece has a sub-fuse part, and the multiple tab pieces are separated from each other, so that when the fuse part is fused due to short circuit, some sub-fuse parts may not be fused, and the already fused sub-fuse parts may be reconnected and adhered to the tab piece that has not been fused, which means that the main body of the battery cell and the pole are still not disconnected electrically, and the fuse part cannot play the role of large current protection. UTILITY MODEL CONTENTS

[0005] The utility model aims at providing a battery to ensure that the fuse part of the tab can be completely fused at a set current threshold, and ensure the safety of the battery.

[0006] In order to solve the above technical problems, the utility model provides the following technical scheme:

[0007] A battery comprises:

[0008] A shell having an opening;

[0009] A cover plate is provided on the opening, and a through hole is formed in the cover plate;

[0010] A pole is at least partially arranged in the through hole;

[0011] A battery cell comprises a main body and a tab, the main body is arranged in the shell, the tab comprises a first connecting part, a fuse part and a second connecting part connected in sequence, the cross-sectional area of the first connecting part and the second connecting part is greater than that of the fuse part, the first connecting part is connected with the main body, and the second connecting part is connected with the end of the pole in the shell;

[0012] The tab includes a plurality of tab pieces stacked together, the tab pieces include a first sub-connection part, a sub-fuse part and a second sub-connection part connected in sequence, all the first sub-connection parts of the tab are stacked together to form the first connection part, all the second sub-connection parts of the tab are stacked together to form the second connection part, and all the sub-fuse parts of the tab are welded together to form the fuse part and form a first welding mark on the side of the tab.

[0013] Compared with the prior art, the battery has the beneficial effects that:

[0014] In the utility model, since the tab includes a plurality of tab pieces stacked together, the tab pieces include a first sub-connection part, a sub-fuse part and a second sub-connection part connected in sequence, the first sub-connection part is connected with the cell main body, the second sub-connection part is welded with the pole, the second sub-connection parts of the plurality of tab pieces are welded together and welded with the pole, and then the plurality of sub-fuse parts of the plurality of tab pieces are welded together, so that when the set current threshold is reached, the plurality of sub-fuse parts can ensure simultaneous fusing to smoothly cut off the electrical connection between the cell main body and the pole. BRIEF DESCRIPTION OF DRAWINGS

[0015] Fig. 1 It is the structural schematic diagram of the battery of the utility model embodiment;

[0016] Fig. 2 It is the relationship schematic diagram of the cell main body, the tab and the pole of the utility model embodiment;

[0017] Fig. 3 It is the one size schematic diagram in the cell main body, the tab and the pole of the utility model embodiment;

[0018] Fig. 4 It is another size schematic diagram in the cell main body, the tab and the pole of the utility model embodiment.

[0019] In the drawing, 100, shell;200, cover plate;300, first welding mark;400, second welding mark;1, cell main body;

[0020] 2, tab;21, first connection part;22, fuse part;23, second connection part;

[0021] 3, pole. DETAILED DESCRIPTION

[0022] The specific embodiments of the present application will be further described in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application, but not to limit the scope of the present application.

[0023] In the description of the present application, it should be understood that the phrase "comprising" used in the present application specification means that the features, integers, steps, operations, components and / or assemblies exist, but does not exclude the presence or addition of one or more other features, integers, steps, operations, components, assemblies and / or their combinations. It should be understood that when we say that a component is "connected" to another component, it can be directly connected to the other component, or there can be an intermediate component. The phrase "and / or" used herein includes all or any unit and all combinations of the associated listed items.

[0024] As shown in Figs. 1 to 4 The present application relates to a battery, which comprises a shell 100, a cover plate 200, a pole 3 and a battery cell, the shell 100 has an opening, the cover plate 200 is arranged on the opening, a through hole is formed in the cover plate 200, and the pole 3 is at least partially arranged in the through hole.

[0025] The battery cell comprises a battery cell body 1 and a tab 2, the battery cell body 1 is arranged in the shell 100, the tab 2 comprises a first connecting part 21, a fuse part 22 and a second connecting part 23 connected in sequence, the cross-sectional area of the first connecting part 21 and the second connecting part 23 is greater than that of the fuse part 22, the first connecting part 21 is connected with the battery cell body 1, and the second connecting part 23 is connected with the end part of the pole 3 in the shell 100.

[0026] The tab 2 comprises a plurality of tab pieces stacked together, the tab piece comprises a first sub-connecting part, a sub-fuse part and a second sub-connecting part connected in sequence, all the first sub-connecting parts of the tab 2 are stacked together to form the first connecting part 21, all the second sub-connecting parts of the tab 2 are stacked together to form the second connecting part 23, and all the sub-fuse parts of the tab 2 are welded together to form the fuse part 22, and a first welding mark 300 is formed on the side surface of the tab 2.

[0027] In the utility model, since the tab 2 includes multiple tabs laminated together, the tab includes a first sub connecting portion, a sub fuse portion and a second sub connecting portion connected in sequence, the first sub connecting portion is connected with the battery cell main body 1, the second sub connecting portion is welded with the pole 3, the second sub connecting portions of multiple tabs are welded together and welded with the pole 3, then multiple sub fuse portions of multiple tabs are welded together, so that when reaching the set current threshold, multiple sub fuse portions can ensure simultaneous fusing to smoothly cut off the electrical connection between the battery cell main body 1 and the pole 3.If the sub fuse portions of multiple tabs are separated from each other, when the fusing portion 22 fuses, there can be some sub fuse portions that do not fuse, and the sub fuse portions that have fused can re-lap and adhere to the tabs that have not fused, which is equivalent to the battery cell main body 1 and the pole 3 still not cutting off the electrical connection, and cannot play the large current protection role of the fusing portion 22.

[0028] In an embodiment thereof, the partial areas of all sub fuse portions of the tab 2 are welded together, and the area of the first welding mark 300 is smaller than the area of the side surface of the fusing portion 22. In this way, the problem of lap adhesion between the fused and unfused sub fuse portions can also be prevented.

[0029] In another embodiment, the entire areas of all sub fuse portions of the tab 2 are welded together, and the area of the first welding mark 300 is equal to the area of the side surface of the fusing portion 22. In this way, the problem of lap adhesion between the fused and unfused sub fuse portions can also be prevented.

[0030] In another embodiment, the entire areas of all sub fuse portions of the tab 2 are welded together, and the area of the first welding mark 300 is equal to the area of the side surface of the fusing portion 22. In this way, the problem of lap adhesion between the fused and unfused sub fuse portions can also be prevented.

[0031] Specifically, the area between the first sub connecting portion and the second sub connecting portion of the tab can be welded together first, and then cutting or punching is performed in the welded area to reduce the cross-sectional area of the welded area, so that the fusing portion 22 is formed at the position of the minimum cross-sectional area, so as to improve the assembly efficiency and avoid the need to cut the multiple tabs individually.

[0032] Preferably, the side surface of the outermost tab forms the first welding mark 300, and in the heat transfer path of the battery cell to the pole 3, the distance between the end of the first welding mark 300 close to the second sub connecting portion and the end of the sub fuse portion of the tab close to the second sub connecting portion is L1, wherein 1mm≤L1≤8mm.

[0033] When the distance between the end of the first welding mark 300 close to the second sub-connection part and the end of the sub-fuse part of the tab close to the second sub-connection part is too large, it indicates that the first welding mark 300 is too close to the welding mark between the tab 2 and the pole 3, and due to the assembly tolerance, the two welding marks may overlap, resulting in secondary repeated welding. The strength of the position after two weldings will decrease, causing the tab 2 to be prone to breakage, and the maximum current threshold of the fuse part 22 will also deviate. When the distance between the end of the first welding mark 300 close to the second sub-connection part and the end of the sub-fuse part of the tab close to the second sub-connection part is too small, the multiple sub-fuse parts of the multiple tab pieces away from the welding equipment area may not be completely welded together, resulting in a partial area separation condition. Therefore, when the multiple sub-fuse parts of the multiple tab pieces reach the originally set current threshold and fuse, the multiple sub-fuse parts may still be bonded, which is equivalent to the fact that the main body 1 of the battery and the pole 3 are still not disconnected, and the fuse part 22 cannot play the role of large current protection. Therefore, the distance L1 between the end of the first welding mark 300 close to the second sub-connection part and the end of the sub-fuse part of the tab close to the second sub-connection part is kept between 1-8mm, which is beneficial to ensure the safety of the battery.

[0034] Further, the side surface of the tab piece located at the outermost side forms the first welding mark 300. In the heat transfer path of the battery cell to the pole 3, the distance between the end of the first welding mark 300 close to the first sub-connection part and the end of the sub-fuse part of the tab close to the first sub-connection part is L2, wherein 1mm≤L2≤8mm.

[0035] When the distance between the first welding mark 300 near the first sub connecting part and the sub melting part of the tab near the first sub connecting part is too large, it indicates that the first welding mark 300 is too close to the main body 1 of the battery cell, which is equivalent to the case that the sub melting parts of multiple tab pieces are welded together, and the high temperature generated by welding may ablate the main body 1 of the battery cell, causing the loss of electrical performance of the main body 1 of the battery cell or a thermal safety risk. When the distance between the first welding mark 300 near the first sub connecting part and the sub melting part of the tab near the first sub connecting part is too small, the multiple sub melting parts of the multiple tab pieces far away from the welding equipment area may not be completely welded together, and the partial area separation may occur, so that when the multiple sub melting parts of the multiple tab pieces reach the original set current threshold to be melted, the multiple sub melting parts may still be bonded, which is equivalent to that the main body 1 of the battery cell and the pole 3 are still not electrically connected, and the melting part 22 cannot play the large current protection role. Therefore, the distance L2 between the first welding mark 300 near the first sub connecting part and the sub melting part of the tab near the first sub connecting part is kept between 1-8mm, which is beneficial to ensure the safety of the battery.

[0036] In the embodiment, the second connecting part 23 is welded with the end of the pole 3 located in the shell 100 to form a second welding mark 400, and the distance between the first welding mark 300 and the second welding mark 400 in the heat transfer path of the battery cell to the pole 3 is L3, wherein 1mm≤L3≤5mm.

[0037] That is, the second welding mark 400 formed by the connection of the second connecting part 23 of the tab 2 and the pole 3 and the first welding mark 300 on the tab 2 are kept at a distance, so that the multiple tab pieces of the tab 2 located between the first welding mark 300 and the second welding mark 400 are dispersed, so as to play a role of buffering the pulling to ensure that the vibration is not easily transmitted to the melting part 22 of the tab 2 through the pole 3, so that the melting part 22 is not easily broken. Moreover, the distance L3 between the first welding mark 300 and the second welding mark 400 is kept between 1-5mm, so that the second welding mark 400 is not too close to the first welding mark 300, so as to have a buffering effect, and the first welding mark 300 is also not too close to the main body 1 of the battery cell, so as to avoid the influence of the temperature during welding on the main body 1 of the battery cell.

[0038] Preferably, in the heat transfer path of the battery cell to the pole 3, the distance between the end of the melting part 22 far away from the first connecting part 21 and the end of the melting part 22 near the first connecting part 21 is L4, wherein 0.4≤L4 / L3≤8.

[0039] When the ratio of the distance L4 between the end of the fuse portion 22 away from the first connecting portion 21 and the end of the fuse portion 22 close to the first connecting portion 21 to the distance L3 between the first welding mark 300 and the second welding mark 400 is too large, it indicates that the length of the fuse portion 22 is large, and the fuse portion 22 is easily broken by vibration, and the distance between the first welding mark 300 and the second welding mark 400 is short, and the buffering capacity provided is weak, so that the fuse portion 22 is easily broken; when the ratio of the distance L4 between the end of the fuse portion 22 away from the first connecting portion 21 and the end of the fuse portion 22 close to the first connecting portion 21 to the distance L3 between the first welding mark 300 and the second welding mark 400 is too small, it indicates that the length of the fuse portion 22 is small, and the distance between the first welding mark 300 and the second welding mark 400 is long, which will cause the fuse portion 22 to not meet the requirement of the fuse time. Therefore, keeping L4 / L3 between 0.4-8 can ensure the smooth use of the fuse portion 22.

[0040] In other embodiments, the second connecting portion 23 is welded with the end of the pole 3 inside the shell 100, and forms the second welding mark 400, and the first welding mark 300 and the second welding mark 400 are connected together.

[0041] That is, a welding is directly made on the tab 2, a long strip is welded when the tab 2 and the pole 3 are welded, and then the welded area is cut to form the fuse portion 22, which can improve the efficiency of assembly.

[0042] In the present embodiment, the second connecting portion 23 is welded with the end of the pole 3 inside the shell 100, and forms the second welding mark 400, and the distance between the fuse portion 22 and the second welding mark 400 in the path of heat transmission from the tab 2 to the pole 3 is L5, wherein 1mm≤L5≤10mm.

[0043] When the distance between the fuse portion 22 and the second welding mark 400 in the path of heat transmission from the tab 2 to the pole 3 is too small, the heat of the welding of the tab 2 and the pole 3 can affect the fuse portion 22, causing partial melting of the fuse portion 22, and the fuse portion 22 is too close to the pole 3, and is also easily broken by pulling or vibration, affecting the performance of the fuse portion 22; when the distance between the fuse portion 22 and the second welding mark 400 is too large, it means that the fuse portion 22 is far away from the pole 3, and is close to the main body 1 of the battery, which can affect the performance of the main body 1 of the battery. Therefore, keeping the distance L5 between the fuse portion 22 and the second welding mark 400 between 1-10mm can ensure the performance of the battery.

[0044] It is emphasized that the area of the first welding mark 300 and the second welding mark 400 refers to the area of the welding area.

[0045] The above merely describes preferred embodiments of the present application, and it should be noted that, for those skilled in the art, without departing from the technical principles of the present application, a number of improvements and replacements can be made, and these improvements and replacements should also be considered as the protection scope of the present application.

Claims

1. A battery, characterized in that, include: A housing having an opening; A cover plate, which is disposed over the opening, and has a through hole; An electrode post, wherein at least a portion of the electrode post is disposed within the through hole; A battery cell, comprising a battery cell body and electrode tabs, wherein the battery cell body is disposed within the housing, and the electrode tabs comprise a first connecting portion, a fusible portion, and a second connecting portion connected in sequence, wherein the cross-sectional areas of the first connecting portion and the second connecting portion are both larger than the cross-sectional area of ​​the fusible portion, the first connecting portion is connected to the battery cell body, and the second connecting portion is connected to the end of the electrode post located within the housing; The electrode tab includes multiple stacked electrode tab pieces. Each electrode tab includes a first sub-connecting portion, a sub-fuse portion, and a second sub-connecting portion connected in sequence. All the first sub-connecting portions of the electrode tab are stacked together to form the first connecting portion. All the second sub-connecting portions of the electrode tab are stacked together to form the second connecting portion. All the sub-fuse portions of the electrode tab are welded together to form the fuse portion, and a first solder mark is formed on the side of the electrode tab.

2. The battery according to claim 1, characterized in that, The portions of all the sub-fusible parts of the electrode tab are welded together.

3. The battery according to claim 1, characterized in that, All areas of the sub-fuse portions of the electrode tab are welded together, and the area of ​​the first weld mark is equal to the area of ​​the side surface of the fuse portion.

4. The battery according to claim 1, characterized in that, All areas of the sub-fuse portions of the electrode tab are welded together, and the area of ​​the first weld mark is larger than the area of ​​the side of the fuse portion.

5. The battery according to claim 4, characterized in that, The first solder mark is formed on the side of the outermost tab. On the path of heat transfer from the cell to the terminal post, the distance between the end of the first solder mark near the second sub-connection and the end of the sub-fuse portion of the tab near the second sub-connection is L1, where 1mm≤L1≤8mm.

6. The battery according to claim 4, characterized in that, The first solder mark is formed on the side of the outermost tab. On the path of heat transfer from the cell to the electrode post, the distance between the end of the first solder mark near the first sub-connection and the end of the sub-fuse portion of the tab near the first sub-connection is L2, where 1mm≤L2≤8mm.

7. The battery according to claim 1, characterized in that, The second connection part is welded to the end of the electrode located inside the housing to form a second solder mark. On the path of heat transfer from the cell to the electrode, the distance between the first solder mark and the second solder mark is L3, where 1mm≤L3≤5mm.

8. The battery according to claim 7, characterized in that, On the path of heat transfer from the cell to the electrode, the distance between the end of the fuse portion away from the first connection portion and the end of the fuse portion close to the first connection portion is L4, where 0.4≤L4 / L3≤8.

9. The battery according to claim 1, characterized in that, The second connecting part is welded to the end of the pole located inside the housing to form a second weld mark, and the first weld mark and the second weld mark are connected together.

10. The battery according to claim 1, characterized in that, The second connection part is welded to the end of the electrode located inside the housing to form a second weld mark. On the path of heat transfer from the cell to the electrode, the distance between the fused part and the second weld mark is L5, where 1mm≤L5≤10mm.

Images