Battery structure with tabs arranged at head

Abstract

The utility model discloses a battery structure with tabs arranged at the head part, and relates to the technical field of battery structures, the head part of a battery cell is provided with an outer ring part and an inner convex part which respectively correspond to two poles; the outer diameter of the protective plate is smaller than that of the cross section of the battery cell; two electrode ports are formed in the front surface; the outer diameter of the insulating protective shell is smaller than or equal to that of the cross section of the battery cell, a cavity is formed in the insulating protective shell, and an opening is formed in the bottom of the cavity; the protective shell is provided with a first step and a second step in the cavity; during assembly, the protective shell is mounted at the head of the battery cell; the second step is limited at the first step; the first tab and the second tab are positioned in the cavity; after bending, one end of the first tab is connected with the first electrode port, and the other end of the first tab extends to the bottom of the protective shell and is connected with the outer ring part; one end of the second tab is connected with the second electrode port, and the other end of the second tab extends and is limited on the second step, and then extends and is connected with the inner convex part. And finally, the internal resistance is effectively reduced, the outer diameter of the battery is prevented from being increased, and the battery protection performance is enhanced.

Description

Technical Field

[0001] This utility model relates to the field of battery structure technology, specifically to a battery structure with tabs located at the head. Background Technology

[0002] In lithium batteries, "tabs" refer to the protruding parts that connect the positive and negative electrode materials to the current collectors (usually metal sheets). These metal sheets are fixed to the battery electrodes by welding or bonding. After the battery is assembled, the tabs connect the internal circuitry of the cell to the external circuitry, enabling the battery to charge and discharge.

[0003] In traditional single-cell lithium batteries, the positive and negative electrodes are usually located at the beginning and end of the cell, while the tabs are metal sheet structures. One of the tabs needs to cross the beginning and end of the cell to conduct the circuit. The resulting battery product has the following problems:

[0004] (1) Due to the large length of the tabs, the electron flow path is long after the battery is powered on, which will significantly increase the internal resistance of the battery. Correspondingly, it will also generate more heat when powered on.

[0005] (2) The battery cell is usually cylindrical, but the tabs need to be bent when connected. The bent tabs form sharp edges and cannot be tightly attached to the outer wall of the battery cell. This results in an increase in the maximum diameter of the finished cylindrical battery and an uneven or difficult-to-flatten surface of the battery.

[0006] (3) The head of the battery cell has a protection board to protect the charging and discharging circuits and prevent voltage and current overload. The surface (front and / or back) of the protection board has electronic components; however, the existing battery packaging has poor overall impact resistance. After the battery is assembled, the external force generated will directly act on the protection board and damage the components on the protection board. Summary of the Invention

[0007] In response to the problems in related technologies, this utility model proposes a battery structure with tabs located at the head, which can effectively shorten the length of the tabs, reduce internal resistance, avoid increasing the outer diameter of the battery by the tabs, improve space utilization, and enhance the protection performance of the protection board.

[0008] This utility model is implemented as follows:

[0009] A battery structure with tabs located at the head includes a battery cell, a protection board, a first tab, and a second tab.

[0010] The battery cell is cylindrical, with a raised outer ring at the head and an inner convex portion nested within the outer ring, corresponding to the two poles of the battery cell respectively; the outer diameter of the protection plate is smaller than the cross-sectional outer diameter of the battery cell, and the front of the protection plate is provided with a first electrode port and a second electrode port.

[0011] It also includes a protective shell; the protective shell is made of insulating material and its outer diameter is less than or equal to the cross-sectional outer diameter of the battery cell; the protective shell has a cavity inside and an opening at the bottom of the cavity; the protective shell has a first step and a second step respectively from top to bottom on the inner sidewall of the cavity;

[0012] During assembly, the protective shell is installed on the head of the battery cell, with the opening facing the head of the battery cell; the back of the protective plate faces the head of the battery cell, and the protective plate is positioned at the first step; both the first tab and the second tab are located within the cavity; after bending, one end of the first tab is connected to the first electrode port, and the other end extends to the area between the bottom of the protective shell and the outer ring, and connects to the outer ring; one end of the second tab is connected to the second electrode port, and the other end extends and is positioned on the second step, and then extends further and connects to the inner protrusion.

[0013] The electrodes of the battery cell are all located on the top of the cell, which can effectively shorten the required length of the tabs and reduce the internal resistance of the battery. Furthermore, the tabs do not need to be laid along the outer surface of the cell, avoiding the increase in the outer diameter of the battery due to the sharp edges formed by the bending of the tabs. The protective shell is made of insulating material, which can provide solid protection for the tabs and the protective plate on the top of the cell, avoiding external pressure. Moreover, one end of each of the two tabs is respectively located on the bottom of the protective shell and above the second step, preventing the two tabs from contacting each other and causing a short circuit.

[0014] The insulating material of the protective shell is PC, PP, or PE, etc., and the material must be fire-resistant and anti-static, with a fire rating of UL94V-1 or UL94V-0. Other materials that meet the above requirements are also acceptable.

[0015] As a further optimization of the above solution, the protective shell includes an annular cylindrical member with openings at both the top and bottom ends; the cavity is formed inside the annular cylindrical member; the inner wall of the annular cylindrical member protrudes inward along the bottom edge to form an annular second step; above the second step, the annular cylindrical member contracts outward along the inner wall to form an annular first step;

[0016] The first step is also provided with a first slot and a second slot; the first slot extends downward and penetrates the second step; the second slot extends downward to the upper side of the second step;

[0017] The protective shell also includes a top cover, which is connected to the upper opening of the annular component.

[0018] The first electrode body extends along the first slot, and the second electrode body extends along the second slot.

[0019] As a further optimization of the above solution, the first electrode tab includes a welding part and a bending part; the welding part is a full ring or a semi-ring; the welding part extends outward to form a strip-shaped bending part; the lower side of the welding part is connected to the outer ring part, and the upper side is connected to the lower side of the second step; the bending part is bent, and the end extends along the first slot and bypasses the protective plate to connect with the first electrode port.

[0020] As a further optimization of the above solution, the bent part and the welded part are provided with a release groove at the connection, and the release groove is in the shape of an angle or an arc.

[0021] A release groove is provided so that the bent part and the welded part shrink at the connection, making it easier for the bent part to bend relative to the welded part.

[0022] As a further optimization of the above scheme, the width of the bending part is 3-5mm and the length is 4-8mm; the outer diameter of the welding part is 0-1.5mm smaller than the cross-sectional outer diameter of the battery cell; the width of the welding part is 0.5-3mm; the thickness of the first electrode tab is 0.1-0.2mm; and the end of the bending part is two right angles or two rounded corners.

[0023] As a further optimization of the above scheme, the second electrode tab is a long strip-shaped structure; the second electrode tab is bent several times, one end of which is connected to the second electrode port, and the other end extends along the second slot to the upper side of the second step, and then extends and connects with the inner protrusion.

[0024] Here, "several" refers to any number of times.

[0025] As a further optimization of the above scheme, the width of the second electrode tab is 2-6 mm and the thickness is 0.1-0.2 mm.

[0026] As a further optimization of the above solution, the top edge of the ring cylinder is provided with two opposing slots; the outer peripheral edge or bottom edge of the top cover has a protrusion; the protrusion is connected to the slot;

[0027] The top edge or side wall of the ring cylinder is also provided with a wire passage; the protective plate is also connected to two lead wires, which pass through the wire passage.

[0028] The battery is connected to an external circuit via leads. The use of protrusions and bayonets facilitates the assembly, disassembly, and fixing of the top cover and the ring cylinder.

[0029] As a further optimization of the above solution, the welding part is welded to the outer ring part to form one or multiple weld lines or multiple evenly distributed weld points, and the weld line is wavy.

[0030] The second electrode tab is welded to the inner protrusion.

[0031] Welding is completed through methods such as laser pulse spot welding, laser continuous welding, resistance welding, and soldering.

[0032] As a further optimization of the above solution, the protective shell and the first electrode tab are fixedly connected by adhesive.

[0033] The adhesive used is AB glue, UV glue, or silicone sealant, etc.

[0034] The beneficial effects are as follows:

[0035] This invention provides a battery structure with tabs located at the top. By adjusting the structure of the two electrodes of the cell, all electrodes are located at the top of the cell, effectively shortening the required tab length and reducing the battery's internal resistance. Furthermore, the tabs do not need to be laid along the outer surface of the cell, avoiding the increase in battery outer diameter caused by the sharp edges formed by the tab bending. The protective shell uses insulating material, providing robust protection for the tabs and protection plate at the top of the cell, preventing external pressure. One end of each tab is positioned at the bottom of the protective shell and above the second step, respectively, preventing short circuits caused by contact between the two tabs. Ultimately, this effectively reduces internal resistance, prevents an increase in battery outer diameter, improves space utilization, and enhances the protection performance of the protection plate and its components. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the structure of a battery in the prior art;

[0037] Figure 2 This is a schematic diagram of the battery structure provided in Example 1;

[0038] Figure 3 for Figure 1 Exploded view;

[0039] Figure 4 for Figure 1 A magnified view of point a;

[0040] Figure 5 A schematic diagram of the welding of the first electrode tab (unbent) and the battery cell provided in Example 1;

[0041] Figure 6 This is a cross-sectional schematic diagram of the ring cylinder provided in Example 1;

[0042] Figure 7 for Figure 1 A cross-sectional diagram;

[0043] Figure 8 This is a schematic diagram of the welding of the first electrode tab after it has been unfolded, as provided in Embodiment 2 of the present invention;

[0044] Figure 9 This is a schematic diagram of the welding of the first electrode tab after it has been unfolded, as provided in Embodiment 3 of the present invention;

[0045] Figure 10 This is a welding schematic diagram of the first electrode tab after it has been unfolded, provided in Embodiment 4 of the present invention;

[0046] Figure 11 This is a welding schematic diagram of the first electrode tab after it has been unfolded, as provided in Embodiment 5 of the present invention;

[0047] Figure 12 This is a schematic diagram of the first electrode tab after it has been unfolded, as provided in Embodiment 6 of the present invention;

[0048] Figure 13 This is a schematic diagram of the first electrode tab after it has been unfolded, as provided in Embodiment 7 of the present invention.

[0049] Figure label:

[0050] 1. Battery cell; 11. Outer ring; 12. Inner protrusion;

[0051] 2. Protection board; 21. First electrode port; 22. Second electrode port; 23. Lead wire;

[0052] 3. First electrode lug; 31. Welding part; 32. Bending part; 321. Rounded corner; 322. Right angle; 33. Release groove;

[0053] 4. Second pole ear;

[0054] 5. Protective shell; 51. Ring cylinder; 511. First step; 512. Second step; 513. First slot; 514. Second slot; 515. Bayonet; 516. Threading port; 52. Top cover; 521. Protrusion;

[0055] 6. Solder joints;

[0056] 7. Solder wire. Detailed Implementation

[0057] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present utility model, and not all of them. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0058] Example 1

[0059] like Figures 2 to 7 As shown, this embodiment provides a battery structure with tabs located at the head, including a battery cell 1, a protection board 2, a first tab 3 and a second tab 4, and a protective shell 5.

[0060] The battery cell 1 is cylindrical, and the head of the battery cell 1 has a raised outer ring 11 and an inner convex part 12 nested in the outer ring 11, which correspond to the negative and positive terminals of the battery cell 1, respectively.

[0061] The outer diameter of the protection plate 2 is smaller than the cross-sectional outer diameter of the battery cell 1. The front side of the protection plate 2 is provided with a first electrode port 21 and a second electrode port 22, which correspond to the negative and positive terminals, respectively. The protection plate 2 is also connected to two leads 23 for connecting to external circuits.

[0062] Correspondingly, the first electrode tab 3 is a negative electrode tab, used to connect the outer ring portion 11 and the first electrode port 21; the second electrode tab 4 is a positive electrode tab, used to connect the inner protrusion portion 12 and the second electrode port 22.

[0063] In this embodiment, the first tab 3 includes a welding portion 31 and a bending portion 32; the welding portion 31 is fully annular; the welding portion 31 extends outward to form a strip-shaped bending portion 32; wherein, the width of the bending portion 32 is 4mm and the length is 5mm; the outer diameter of the welding portion 31 is 1mm smaller than the outer diameter of the cross-section of the battery cell 1; the width of the welding portion 31 is 1mm; the thickness of the first tab 3 is 0.2mm; the ends of the bending portion 32 are two right angles 322.

[0064] In this embodiment, the second tab 4 is a strip-shaped structure with a width of 4 mm and a thickness of 0.2 mm.

[0065] In this embodiment, the protective shell 5 is made of PP material, which has anti-static properties and a fire rating of UL94V-1. Its outer diameter is less than or equal to the cross-sectional outer diameter of the battery cell 1. Specifically, the protective shell 5 includes an annular cylindrical member 51 with openings at both the top and bottom ends; the interior of the annular cylindrical member 51 forms a cavity; the inner wall of the annular cylindrical member 51 protrudes inward along the bottom edge to form an annular second step 512; above the second step 512, the annular cylindrical member 51 contracts outward along the inner wall to form an annular first step 511.

[0066] The first step 511 is also provided with a first slot 513 and a second slot 514; the first slot 513 extends downward and penetrates the second step 512; the second slot 514 extends downward to the upper side of the second step 512.

[0067] In addition, the first step 511 and the second step 512 extend upwards and form two notches 515 at the upper opening edge of the annular cylinder 51. The top edge of the annular cylinder 51 is also provided with a threading port 516 for the lead wire 23 to pass through.

[0068] The protective shell 5 also includes a top cover 52, which fits the upper opening of the ring cylinder 51. The outer peripheral edge of the top cover 52 has a protrusion 521; the protrusion 521 fits the size of the snap-fit ​​515.

[0069] During assembly, the welding part 31 of the first electrode 3 is aligned with the outer ring 11, and the welding part 31 is welded to the outer ring 11 by laser pulse spot welding to form multiple evenly distributed weld points 6. At the same time, one end of the second electrode 4 is welded to the inner protrusion 12.

[0070] The bending portion 32 of the first electrode lug 3 is bent vertically upward, and the other end of the second electrode lug 4 is bent vertically upward. AB glue is applied to the upper side of the welding portion 31. The lower opening of the annular portion faces the welding portion 31, the first slot 513 is aligned with the bending portion 32, and the second slot 514 is aligned with the second electrode lug 4. The annular portion and the welding portion 31 are fixedly connected, and the bending portion 32 and the second electrode lug 4 are bent and adjusted so that they extend along the first slot 513 and the second slot 514 respectively. At this time, the second electrode lug 4 is limited to the upper side of the second step 512.

[0071] Place the protective plate 2 on the upper side of the first step 511, with the back facing the head of the cell 1. Continue to bend the first tab 3 and the second tab 4, and weld the first tab 3 to the first electrode port 21, the second tab 4 to the second electrode port 22. Finally, connect the top cover 52 to the upper opening of the ring cylinder 51.

[0072] It should be noted that the bending sequence and the connection sequence of each component are not fixed. This embodiment only illustrates one possible method of battery assembly.

[0073] The electrodes of cell 1 are all located on the top of cell 1, which can effectively shorten the required length of the tabs and reduce the internal resistance of the battery. The tabs do not need to be laid along the outer surface of cell 1, avoiding the increase of the outer diameter of the battery due to the sharp corners formed by the bending of the tabs. The protective shell 5 is made of insulating material, which can provide solid protection for the tabs and the protective plate 2 on the top of cell 1, avoiding external pressure. One end of each of the two tabs is respectively located on the bottom of the protective shell 5 and above the second step 512, to prevent the two tabs from contacting and causing a short circuit.

[0074] Example 2

[0075] This implementation example Figure 8 As shown, features not explained in this embodiment are explained using the method described in Embodiment 1, and will not be repeated here. The difference between this embodiment and Embodiment 1 is:

[0076] The ends of the bent portion 32 are two rounded corners 321.

[0077] Example 3

[0078] This implementation example Figure 9As shown, features not explained in this embodiment are explained using the method described in Embodiment 2, and will not be repeated here. The difference between this embodiment and Embodiment 2 is:

[0079] Using a continuous laser welding method, after the welding operation is completed in the welding section 31, a wavy weld line 7 is formed, and the amplitude of the weld line 7 is 0.2mm.

[0080] Example 4

[0081] This implementation example Figure 10 As shown, features not explained in this embodiment are explained using the method described in Embodiment 3, and will not be repeated here. The difference between this embodiment and Embodiment 3 is:

[0082] The welding section 31 has a semi-annular structure. After the welding operation, two segmented wavy strip welding lines 7 are formed.

[0083] Example 5

[0084] This implementation example Figure 11 As shown, features not explained in this embodiment are explained using the method described in Embodiment 4, and will not be repeated here. The difference between this embodiment and Embodiment 4 is:

[0085] After the welding operation, a wavy strip weld line is formed 7.

[0086] Example 6

[0087] This implementation example Figure 12 As shown, features not explained in this embodiment are explained using the method described in Embodiment 1, and will not be repeated here. The difference between this embodiment and Embodiment 1 is:

[0088] The bent portion 32 and the welded portion 31 are provided with a release groove 33 at the connection point, and the release groove 33 is at an angle. The release groove 33 is provided so that the bent portion 32 and the welded portion 31 shrink at the connection point, which facilitates the bending portion 32 relative to the welded portion 31.

[0089] Example 7

[0090] This implementation example Figure 13 As shown, features not explained in this embodiment are explained using the method described in Embodiment 1, and will not be repeated here. The difference between this embodiment and Embodiment 1 is:

[0091] The bent portion 32 and the welded portion 31 are provided with a release groove 33 at the connection, and the release groove 33 is in the shape of a bend.

[0092] Based on the disclosure and teachings of the above specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, this utility model is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the utility model should also fall within the protection scope of the claims of this utility model. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on this utility model.

Claims

1. A battery structure with tabs located at the head, comprising a battery cell, a protection board, a first tab, and a second tab; characterized in that: The battery cell is cylindrical, with a raised outer ring at the head and an inner convex portion nested within the outer ring, corresponding to the two poles of the battery cell respectively; the outer diameter of the protection plate is smaller than the cross-sectional outer diameter of the battery cell, and the front of the protection plate is provided with a first electrode port and a second electrode port. It also includes a protective shell; the protective shell is made of insulating material and its outer diameter is less than or equal to the cross-sectional outer diameter of the battery cell; the protective shell has a cavity inside and an opening at the bottom of the cavity; the protective shell has a first step and a second step respectively from top to bottom on the inner sidewall of the cavity; During assembly, the protective shell is installed on the head of the battery cell, with the opening facing the head of the battery cell; the back of the protective plate faces the head of the battery cell, and the protective plate is positioned at the first step; both the first tab and the second tab are located within the cavity; after bending, one end of the first tab is connected to the first electrode port, and the other end extends to the area between the bottom of the protective shell and the outer ring, and connects to the outer ring; one end of the second tab is connected to the second electrode port, and the other end extends and is positioned on the second step, and then extends further and connects to the inner protrusion.

2. The battery structure with tabs located on the head according to claim 1, characterized in that: The protective shell includes an annular cylindrical member with openings at both the top and bottom ends; the cavity is formed inside the annular cylindrical member; the inner wall of the annular cylindrical member protrudes inward along the bottom edge to form an annular second step; above the second step, the annular cylindrical member contracts outward along the inner wall to form an annular first step; The first step is also provided with a first slot and a second slot; the first slot extends downward and penetrates the second step; the second slot extends downward to the upper side of the second step; The protective shell also includes a top cover, which is connected to the upper opening of the annular component.

3. The battery structure with tabs located on the head according to claim 2, characterized in that: The first electrode tab includes a welding portion and a bending portion; the welding portion is full-ring or semi-ring; the welding portion extends outward to form a strip-shaped bending portion; the lower side of the welding portion is connected to the outer ring portion, and the upper side is connected to the lower side of the second step; the bending portion is bent, and its end extends along the first slot and bypasses the protective plate to connect with the first electrode port.

4. The battery structure with tabs located on the head according to claim 3, characterized in that: The bent portion and the welded portion are provided with a release groove at the connection point, and the release groove is in the shape of an angle or an arc.

5. A battery structure with tabs disposed on the head according to claim 3, characterized in that: The width of the bending portion is 3-5 mm and the length is 4-8 mm; the outer diameter of the welding portion is 0-1.5 mm smaller than the cross-sectional outer diameter of the battery cell; the width of the welding portion is 0.5-3 mm; the thickness of the first electrode tab is 0.1-0.2 mm; the end of the bending portion is two right angles or two rounded corners.

6. A battery structure with tabs disposed on the head according to claim 2, characterized in that: The second electrode tab is a long strip-shaped structure; the second electrode tab is bent several times, one end of which is connected to the second electrode port, and the other end extends along the second slot to the upper side of the second step, and then extends and connects with the inner protrusion.

7. A battery structure with tabs disposed on the head according to claim 6, characterized in that: The width of the second electrode tab is 2-6 mm and the thickness is 0.1-0.2 mm.

8. A battery structure with tabs disposed on the head according to claim 2, characterized in that: The top edge of the ring cylinder is provided with two opposing latches; the outer peripheral edge or bottom edge of the top cover has a protrusion; the protrusion is engaged with the latches for connection; The top edge or side wall of the ring cylinder is also provided with a wire passage; the protective plate is also connected to two lead wires, which pass through the wire passage.

9. A battery structure with tabs disposed on the head according to claim 3, characterized in that: The welding part is welded to the outer ring part to form one or multiple weld lines or multiple evenly distributed weld points, and the weld line is wavy. The second electrode tab is welded to the inner protrusion.

10. A battery structure with tabs disposed on the head according to claim 9, characterized in that: The protective shell and the first electrode tab are fixedly connected by glue.

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