CN207353315U - rechargeable battery - Google Patents

Abstract

The utility model provides a rechargeable battery, it includes: the side wall of the negative electrode tank body is provided with a three-stage step structure, and the negative electrode tank body comprises a first stage step, a second stage step and a third stage step with gradually reduced inner diameters from the tail end; the positive current collector is nested in the negative tank body; the sealing ring is arranged between the side wall of the negative electrode tank body and the side wall of the positive current collector and isolates the negative electrode tank body from the positive current collector so as not to contact with the positive current collector and generate short circuit; wherein the sealing ring is tightly attached to the second step of the negative electrode can body to form a sealing part of the battery; the end part of the first step is bent inwards to be attached to the sealing ring to form a sealing position; and the lower portion of the seal ring abuts against the connecting portion between the second-stage step and the third-stage step, thereby obtaining support. The utility model discloses can effectively utilize the space, maximize performance battery capacity to avoid the charge-discharge in-process explosion.

Description

rechargeable battery

technical field

The utility model relates to the field of small batteries, in particular to a rechargeable battery and a manufacturing method thereof.

Background technique

There are many types of small rechargeable batteries available today. Taking the commonly used lithium-ion battery as an example, its shell usually adopts a cylindrical can. Tank material is iron nickel plated or stainless steel.

Figure 1 is a cross-sectional view of a small rechargeable Li-ion battery fabricated according to the prior art. Rechargeable lithium-ion batteries are generally manufactured by:

After the positive and negative electrodes are cut as required, the ends are respectively spot welded on the positive electrode tab 106 and the negative electrode tab 103 . A separator is placed in the middle of the positive and negative electrode sheets, and the positive and negative electrode sheets with the separator added are rolled into a cell roll 102 by winding. Put the lower insulating sheet 104 at the bottom of the can body (ie, the negative terminal 1023 ), and put the cell roll pack 102 into the can body. The negative electrode tab 103 was connected to the side wall of the can by spot welding. Roll a circle at about 1-3mm (for example, 3mm) below the mouth of the can body to form a radial direction about 0.8-2.5mm (for example, 2mm) and 0.5-1.5mm (for example, 1mm) deep. The slot protrudes inward, and the upper insulating sheet 105 is placed under the slot and above the battery core package 102 . Then, put the positive current collector including the outer contact piece (the positive terminal 1020 used as the top cap), the inner contact piece (the positive aluminum cap 1022 ) and the sealing ring 108 into the can. The positive electrode current collector is supported by the protrusions of the grooves. The material of the outer contact sheet is nickel-plated iron sheet, the inner contact sheet is aluminum sheet, and the material of the sealing ring is PP (polypropylene) or other plastic materials. Afterwards, pass the positive electrode tab 106 wrapped with the positive electrode adhesive paper 1021 through the upper insulating sheet 105, and connect it with the positive electrode current collector by spot welding.

After spot welding the positive electrode current collector, the entire battery was baked in an oven at 85° C. for 24 to 36 hours. After cooling, add the electrolyte in an environment with a relative humidity below 1%. Then, insert the positive current collector from the mouth of the can body, and combine with the can body. Use the sealer mold to bend the mouth of the tank to complete the sealing of the battery.

The advantage of the above-mentioned lithium-ion battery is that the assembly technology is relatively mature and it is relatively easy to operate. However, it can be seen from the structure of FIG. 1 that the space occupied by the positive electrode current collector is large, so the overall space of the battery is small, resulting in a small battery capacity.

In addition, when a lithium-ion battery is overcharged or discharged, a large amount of gas may be generated inside the battery. When the gas reaches a certain pressure, the gas will break through the positive electrode seal or the negative electrode tank, resulting in an explosion. Generally, larger lithium-ion batteries will be equipped with explosion-proof devices on the positive electrode collector, but small lithium-ion batteries cannot be equipped with explosion-proof devices because the positive electrode collector is too small. Therefore, small lithium-ion batteries are likely to explode during charging and discharging, and there are hidden dangers in terms of safety.

Therefore, there is a need in the art for a rechargeable battery and a manufacturing method that can effectively utilize space, maximize battery capacity and avoid explosion during charging and discharging.

Utility model content

One of the objectives of the present invention is to provide a small rechargeable battery that can effectively utilize space and maximize battery capacity. Additionally, a further object of the present invention is to provide a small rechargeable battery that can effectively utilize space, maximize battery capacity, and avoid explosion during charging and discharging.

According to one aspect of the present invention, a rechargeable battery is provided, which includes: a negative electrode tank body, which has a three-stage stepped structure at the mouth, and includes a first stage, a second stage, and a second stage with decreasing inner diameters from the end. a step and a third step; a positive current collector, the positive current collector is nested in the negative can; and a sealing ring, the sealing ring is arranged on the mouth of the negative can and the positive current collector Between the mouth and isolate the negative electrode tank and the positive electrode current collector so that they do not contact and short-circuit; wherein the sealing ring is closely attached to the second step of the negative electrode tank to form a sealing part of the battery ; The end of the first step is bent inward to fit the sealing ring to form a sealing position; and the lower part of the sealing ring is against the gap between the second step and the third step on the connecting part for support.

Preferably, the negative electrode can body has at least one hole on the side wall of the first step.

Preferably, the sealing ring has a U-shaped groove, and the mouth of the positive current collector is accommodated in the U-shaped groove. Preferably, the sealing ring is made of insulating and compressible material.

Preferably, the positive electrode current collector has an inverted cup-shaped structure, and the diameter of the mouth of the cup-shaped structure is equal to or greater than the diameter of the bottom of the cup-shaped structure.

Preferably, the battery further includes a cell package formed by winding the positive electrode sheet, the negative electrode sheet, and the separation mechanism between the positive electrode sheet and the negative electrode sheet.

Preferably, a positive electrode tab is extended from the end of the positive electrode sheet, which is connected to the positive electrode current collector; and a negative electrode tab is extended from the end of the negative electrode sheet, which is connected to the negative electrode tank.

Preferably, the battery further includes an upper insulating sheet placed above the battery pack and a lower insulating sheet below the battery pack.

Preferably, when the positive electrode current collector moves upward, the positive electrode tab connected to the positive electrode current collector breaks.

Preferably, the battery is a cylindrical battery, for example cylindrical.

Preferably, the battery is a lithium ion battery, more preferably a cylindrical lithium ion battery.

Description of drawings

The utility model will be further described below in conjunction with accompanying drawing and embodiment, in the accompanying drawing:

Figure 1 is a cross-sectional view of a small rechargeable Li-ion battery fabricated according to the prior art; and

FIG. 2 is a cross-sectional view of a rechargeable lithium-ion battery according to an embodiment of the present invention.

Detailed ways

The following descriptions are typical implementations of the present invention, which are not intended to limit the scope or applicability of the present invention in any way. Rather, the following description is intended to provide examples of various embodiments for practicing the invention.

In the following, the idea and concept of the present utility model will be described in detail by taking a small cylindrical rechargeable lithium-ion battery as an example. However, as those skilled in the art realize, the rechargeable battery of the present invention is not limited to a small lithium-ion battery, nor is it limited to a columnar structure, and other battery structures (for example, button-shaped structures) and materials commonly used in the field are applicable. .

The small-sized lithium-ion battery of the present invention includes a negative electrode tank body, and its interior is configured to accommodate positive and negative electrode sheet rolls (ie, cell rolls). The positive and negative electrode rolls include positive and negative electrodes, which are separated by a separator. The positive and negative electrodes separated by the diaphragm are wound into a cylindrical roll, and then can be wrapped with adhesive tape. A positive pole lug is extended from the end of the positive pole piece, which is connected with the positive current collector. A negative pole lug is extended from the end of the negative pole piece, which is connected with the can body. The roll package of positive and negative electrodes can also be provided with an upper insulating sheet and a lower insulating sheet.

As shown in Figure 2, in a preferred embodiment, the negative electrode tank 1 of the present invention has three steps at its mouth, including a first step 9 and a second step 10 with decreasing inner diameters from the end. and the third rung 11. For example, the inner diameter of the second step 10 may be about 0.05-0.20 mm smaller than that of the first step 9 and about 0.05-0.20 mm smaller than that of the third step 11 . Preferably, the inner diameter of the second step 10 may be about 3-18 mm, depending on the size of the battery. The connection between the second step 10 and the third step 11 can be used to support the bottom of the sealing ring 8 when installing the battery.

Since the second step 10 presses the sealing ring 8 inwardly, a good seal between the negative electrode tank body 1 and the positive electrode fluid 7 has been ensured, therefore, there may be a gap between the first step 9 and the sealing ring and in the gap Can be filled without glue. Of course, in order to further strengthen the sealing, it is also possible to fill the gap with sealing glue.

In a further preferred embodiment, there may be at least one hole in the first step 9 , and the hole passes through the negative electrode can body 1 . In one aspect, 2 to 6 holes, preferably 4 holes, may be provided in the first step 9 . Preferably, the plurality of holes are circumferentially symmetrical. In one aspect, the hole diameter may be 0.10-0.8 mm. The holes can be circular, rectangular, square, prismatic or irregular, preferably irregular.

The thickness of the negative electrode can body 1 can be about 0.10-0.30 mm, and the material can be nickel-plated iron or stainless steel.

In one embodiment, the positive electrode current collector 7 can be in the shape of an inverted cup, and the diameter of the cup mouth can be equal to or larger than the diameter of the bottom of the cup, preferably larger than the diameter of the bottom of the cup, for example, about 0.05-0.30 mm larger, preferably about 0.10-0.15 mm larger. mm. The material of the positive current collector can be nickel-plated iron or stainless steel, and the thickness can be about 0.1-0.35 mm.

A sealing ring 8 may be provided between the side wall of the positive electrode collector 7 and the mouth of the negative electrode can body 1 to seal the battery and prevent short circuit caused by the contact between the negative electrode can body 1 and the positive electrode top cover 7 . Preferably, the sealing ring 8 is an annular structure with a U-shaped groove. Preferably, the material of the sealing ring 8 is compressible.

More specifically, in one embodiment, the sealing ring 8 may have a U-shaped groove, and the thickness may be about 0.05-0.30 mm, preferably about 0.08-0.20 mm. The mouth of the cup can be inserted into the U-shaped groove of the sealing ring 8 . The inner surface of the sealing ring 8 can be in close contact with the outer surface of the cup of the positive current collector 7 . The outer diameter of the sealing ring 8 is preferably substantially the same as the inner diameter of the second step 10 of the negative electrode can body 1, for example, the outer diameter of the sealing ring 8 is the same as or 0.01 to 0.03mm smaller than the second step 10 of the negative electrode can body 1 , the maximum shall not exceed 0.10mm, otherwise it will affect the sealing performance of the battery. The sealing ring material can be polypropylene (PP) or polyether ether ketone (PEEK), or other elastic insulating materials that can be used.

Before the sealing ring 8 is combined with the positive electrode current collector 7, epoxy resin or other glue can be applied to the groove thereof to make the two tightly combined.

When the battery is assembled after adding the electrolyte, the positive electrode current collector 7 is inserted from the mouth of the negative electrode can body 1, and, for example, by pressurizing from the top, the sealing ring 8 combined with the positive electrode current collector 7 is connected to the second stage of the negative electrode can body 1. The steps fit snugly and form the main seal of the battery. The lower part of the sealing ring 8 abuts against the connecting portion between the second step 10 and the third step 11 to obtain support.

Then use the sealing machine mold to narrow the first step 9 so that the end of the first step 9 bends inwards, and fits with the sealing ring 8 to form a sealing position. At this time, the second step 10 of the negative electrode tank 1 will also be stretched inward by the radial force, compressing the sealing ring 8, so that the sealing ring 8 is more closely attached to the tank wall, and the sealing performance is better. After being assembled in this way, the sealing ring 8 is compressed, and its compressed thickness is between 10% and 90% of the original thickness, especially between 30% and 70%, particularly preferably about 50%, so as to achieve good sealing Effect.

Compared with the traditional lithium ion battery of the same volume, the lithium ion battery made of the above structure can increase the internal volume by at least about 10-12% or even higher, so the capacity can be greatly improved without increasing the size of the battery. improve.

In addition, the lithium-ion battery made with the above-mentioned structure also improves the battery capacity and makes the battery safer and more reliable. When the gas generated inside the battery pushes the positive current collector upward during overcharging and discharging, the positive current collector will break away from the second step of the negative tank, and when it reaches the first step, the cup mouth will be covered by the first step. The resulting seal snaps and gas escapes through the pores of the first step, eliminating the risk of the battery exploding due to overpressure. In addition, since there is a gap between the first step and the sealing ring 8 and glue is usually not added, setting the hole in the first step can prevent the glue from clogging the hole, and the existing gap also allows the internal air pressure to be initially released first .

In addition, in order to avoid excessive charging and discharging of the battery, the positive electrode tab connected to the positive electrode current collector or the negative electrode tab connected to the negative electrode can may be broken when the positive electrode current collector moves upward. For example, a tear portion (for example, a tear line structure) may be provided between the positive electrode current collector and the positive electrode tab, which breaks when the positive electrode current collector moves outward for a predetermined distance, thereby cutting off the positive electrode tab and the positive electrode current collector. connection, to avoid generating more gas and causing the battery to explode.

The utility model is described in more detail below in conjunction with FIG. 2 . FIG. 2 is a cross-sectional view of a rechargeable lithium-ion battery according to an exemplary embodiment of the present invention. As shown in Figure 2, a rechargeable Li-ion battery includes a negative electrode casing, a positive electrode top cover, and an insulating seal.

Example 1

The negative electrode casing is a cylindrical can body, that is, the negative electrode can body 1 . The negative electrode tank body 1 is made of stainless steel with a thickness of 0.15 mm and a height of 24 mm. The negative electrode can body 1 shown in FIG. 2 can be made by, for example, a punching machine. There is a three-stage stepped structure at the mouth of the negative electrode tank 1 , including a first step 9 , a second step 10 and a third set of steps 11 with decreasing inner diameters. The inner diameter of the second step 10 is 0.15 mm smaller than that of the first step 9 and 0.20 mm larger than that of the third step 11 . The inner diameter of the second step 10 is 10mm, and the inner wall is coated with sealing glue. There is also at least one air hole 16 on the side wall of the mouth of the negative electrode can body 1 . In this embodiment, the air holes 16 are four in number and arranged symmetrically. The air hole 16 has a diameter of 0.5 mm.

Cut the positive electrode sheet 13 and the negative electrode sheet 14 as required, and spot weld them to the positive electrode tab 6 and the negative electrode tab 3 respectively. A separator 15 is placed between the positive electrode sheet and the negative electrode sheet. Wind the positive and negative electrodes into a cylindrical roll 2 and wrap them with adhesive tape. The height of the roll package 2 is the total height of the battery minus the thickness of the positive and negative current collectors 7 and the two insulating sheets, leaving a space of about 0.5-1 mm.

First put the lower insulating sheet 4 in the inner bottom of the negative electrode tank body 1, and then put it into the roll pack 2. Weld the negative electrode tab 3 with the can body. An upper insulating sheet 5 is placed on the upper part of the roll package 2 , and the positive electrode tab 6 passes through the upper insulating sheet 5 and is welded to the positive electrode current collector 7 .

The positive current collector 7 has an inverted cup-shaped structure, the outer diameter of the cup mouth is 0.15 mm larger than the outer diameter of the cup bottom, and its material is stainless steel with a thickness of 0.15 mm.

Insert the mouth of the cup of the positive current collector 7 into the sealing ring 8 . The sealing ring 8 is an annular shape with a U-shaped groove, and the material is PP. Before combining with the positive electrode current collector 7, apply sealing glue 12 to the groove to make the two tightly combined. The thickness of the sealing ring 8 is 0.15 mm, and its outer diameter is the same as or 0.02 mm smaller than the inner diameter of the second step 10 of the negative electrode tank 1 .

After spot-welding the positive current collector 7, the entire battery was baked in an oven at 85°C for 24-36 hours. After cooling, add the electrolyte in an environment with a relative humidity below 1%. Then insert the positive electrode current collector 7 from the mouth of the negative electrode can body 1, combine with the negative electrode can body 1, and then pressurize from the top, so that the sealing ring 8 is closely attached to the second step 10 of the negative electrode can body 1, and against the negative electrode can body 1. Lean against the connection bracket between the second step and the third step 11 of the negative electrode tank body 1 . Then use the mold of the sealing machine to narrow the first step 9 inwards, so that the mouth of the first step 9 of the tank body is bent inward to fit the sealing ring 8, and the sealing ring 8 is further squeezed.

Example 2

The negative electrode casing is a cylindrical can body, that is, the negative electrode can body 1 . The negative electrode tank body 1 is made of stainless steel with a thickness of 0.15 mm and a height of 24 mm. The negative electrode can body 1 shown in FIG. 2 can be made by, for example, a punching machine. There is a three-stage stepped structure at the mouth of the negative electrode tank 1 , including a first step 9 , a second step 10 and a third set of steps 11 with decreasing inner diameters. The inner diameter of the second step 10 is 0.15 mm smaller than that of the first step 9 and 0.20 mm larger than that of the third step 11 . The inner diameter of the second step 10 is 10mm, and the inner wall is coated with sealing glue. There is also at least one air hole 16 on the side wall of the mouth of the negative electrode can body 1 . In this embodiment, the air holes 16 are four in number and arranged symmetrically. The air hole 16 has a diameter of 0.5 mm.

Cut the positive electrode sheet 13 and the negative electrode sheet 14 as required, and spot weld them to the positive electrode tab 6 and the negative electrode tab 3 respectively. A separator 15 is placed between the positive electrode sheet and the negative electrode sheet. Wind the positive and negative electrodes into a cylindrical roll 2 and wrap them with adhesive tape. The height of the roll package 2 is the total height of the battery minus the thickness of the positive and negative current collectors 7 and the two insulating sheets, leaving a space of about 0.5-1 mm.

First put the lower insulating sheet 4 in the inner bottom of the negative electrode tank body 1, and then put it into the roll pack 2. Weld the negative electrode tab 3 with the can body. An upper insulating sheet 5 is placed on the upper part of the roll package 2 , and the positive electrode tab 6 passes through the upper insulating sheet 5 and is welded to the positive electrode current collector 7 .

The positive current collector 7 has an inverted cup-shaped structure, the outer diameter of the cup mouth is 0.15 mm larger than the outer diameter of the cup bottom, and its material is stainless steel with a thickness of 0.15 mm.

Insert the mouth of the cup of the positive current collector 7 into the sealing ring 8 . The sealing ring 8 is a ring with a U-shaped groove, and the material is polyetheretherketone PEEK. Since the sealing ring is tubular before it is combined with the positive current collector 7, it is first placed on the mouth of the positive current collector 7, and then bent and shrunk inwards with hot air to form a U-shaped groove, which is tightly connected to the positive current collector 7. combined. The thickness of the sealing ring 8 is 0.08 mm, and its outer diameter is the same as or 0.02 mm smaller than the inner diameter of the second step 10 of the negative electrode tank 1 .

After spot-welding the positive current collector 7, the entire battery was baked in an oven at 85°C for 24-36 hours. After cooling, add the electrolyte in an environment with a relative humidity below 1%. Then insert the positive electrode current collector 7 from the mouth of the negative electrode can body 1, combine with the negative electrode can body 1, and then pressurize from the top, so that the sealing ring 8 is closely attached to the second step 10 of the negative electrode can body 1, and against the negative electrode can body 1. Lean against the connection bracket between the second step and the third step 11 of the negative electrode tank body 1 . Then use the mold of the sealing machine to narrow the first step 9 inwards, so that the mouth of the first step 9 of the tank body is bent inward to fit the sealing ring 8, and the sealing ring 8 is further squeezed.

Comparative Example (Existing Structure)

Figure 1 is a cross-sectional view of a small lithium-ion battery manufactured by a conventional method.

The negative electrode tank of the battery is a columnar tank made of 0.15 mm stainless steel sheet, with a diameter of 10 mm and a height of 24 mm.

After the positive and negative electrodes are cut as required, the ends are respectively spot welded on the positive electrode tab 106 and the negative electrode tab 103 . A separator is placed in the middle of the positive and negative electrode sheets, and the positive and negative electrode sheets with the separator added are rolled into a cell roll 102 by winding. Put the lower insulating sheet 104 at the bottom of the can body (ie, the negative terminal 1023 ), and put the cell roll pack 102 into the can body. The negative electrode tab 103 was connected to the side wall of the can by spot welding.

Roll a groove about 2 mm wide and 1 mm deep at a place about 3 mm below the mouth of the tank body, and then place the bottom of the upper insulating sheet 105 and the top of the battery pack 102 . The positive electrode lug passes through the upper insulating sheet 105 and is connected to the positive electrode current collector 7 by spot welding.

The positive current collector 7 includes an outer contact piece 1020 , an inner contact piece 1022 , and a sealing ring 108 . The material of the outer contact sheet is nickel-plated iron sheet, the inner contact sheet is aluminum sheet, and the sealing ring material is PP. Put the positive current collector including the outer contact piece (the positive terminal 1020 used as the top cap), the inner contact piece (the positive aluminum cap 1022 ) and the sealing ring 108 into the can. The positive electrode current collector is supported by the protrusions of the grooves. The material of the outer contact sheet is nickel-plated iron sheet, the inner contact sheet is aluminum sheet, and the material of the sealing ring is PP (polypropylene) or other plastic materials. Afterwards, pass the positive electrode tab 106 wrapped with the positive electrode adhesive paper 1021 through the upper insulating sheet 105, and connect it with the positive electrode current collector by spot welding.

After spot welding the positive electrode current collector, the entire battery was baked in an oven at 85° C. for 24 to 36 hours. After cooling, add the electrolyte in an environment with a relative humidity below 1%. Then, insert the positive current collector from the mouth of the can body, and combine with the can body. Use the sealer mold to bend the mouth of the tank to complete the sealing of the battery.

Result comparison

As can be seen from the comparison of the small lithium ion battery (Fig. 2) made by the above-mentioned embodiment 1 and embodiment 2 and the small lithium ion battery (Fig. 1) made by the comparative example (existing structure), both volume They are basically the same, but the internal space of the battery of Example 1-2 is obviously larger than that of Comparative Example, increasing by about 10-12%. In other words, under the same external volume, the internal space of the battery of the utility model is about 10-12% larger than that of the battery of the traditional structure. Correspondingly, the battery capacity can be increased by 10-12% under the condition that the material and formula remain unchanged.

In addition, the lithium-ion battery made with the above-mentioned structure also improves the battery capacity and makes the battery safer and more reliable. When the gas generated inside the battery pushes the positive current collector upward during overcharging and discharging, the positive current collector will break away from the second step of the negative tank, and when it reaches the first step, the cup mouth will be covered by the first step. The resulting seal snaps and gas escapes through the pores of the first step, eliminating the risk of the battery exploding due to overpressure.

Although the utility model is described through specific embodiments, those skilled in the art should understand that various transformations and equivalent substitutions can also be made to the utility model without departing from the scope of the utility model. In addition, various modifications or replacements can be made to the utility model without departing from the scope of the utility model for specific situations or application requirements. Therefore, the utility model is not limited to the specific embodiments disclosed, but should include all implementations falling within the scope of the claims of the utility model.

Claims (11)

1. A rechargeable battery, characterized in that, the rechargeable battery comprises: The negative electrode tank body has a three-stage stepped structure at the mouth, including a first step, a second step, and a third step with decreasing inner diameters from the end of the mouth; a positive electrode current collector, the positive electrode current collector is nested in the negative electrode can; and A sealing ring, the sealing ring is arranged between the mouth of the negative electrode tank and the mouth of the positive electrode collector and isolates the negative electrode tank and the positive electrode collector so that they do not contact and short-circuit; Wherein the sealing ring is closely attached to the second step of the negative electrode tank to form a sealing part of the battery; The end of the first step is bent inward to fit the sealing ring to form a sealing position; And the lower part of the sealing ring abuts against the connecting part between the second step and the third step, so as to obtain support. 2. The rechargeable battery according to claim 1, wherein the negative electrode can has at least one hole on the side wall of the first step. 3. The rechargeable battery according to claim 1 or 2, wherein the sealing ring has a U-shaped groove, and the mouth of the positive current collector is accommodated in the U-shaped groove. 4. The rechargeable battery according to claim 1 or 2, wherein the sealing ring is made of an insulating and compressible material. 5. The rechargeable battery according to claim 1 or 2, wherein the positive electrode current collector has an inverted cup-shaped structure, and the diameter of the mouth of the cup-shaped structure is equal to or greater than that of the cup-shaped The diameter of the base of the structure. 6. The rechargeable battery according to claim 1 or 2, characterized in that, the battery further comprises a cell coil wound by a positive electrode sheet, a negative electrode sheet, and a separation mechanism between the positive electrode sheet and the negative electrode sheet Bag. 7. The rechargeable battery according to claim 6, wherein a positive pole tab is extended from the end of the positive electrode sheet, which is connected to the positive electrode current collector; and a negative pole tab is extended from the end of the negative electrode sheet, It is connected with the negative electrode tank body. 8 . The rechargeable battery according to claim 7 , wherein the battery further comprises an upper insulating sheet placed above the battery pack and a lower insulating sheet placed below the battery pack. 9 . 9. The rechargeable battery according to claim 7, wherein when the positive current collector moves upward, the positive tab connected to the positive current collector breaks. 10. The rechargeable battery according to claim 1, wherein the battery is a cylindrical battery. 11. The rechargeable battery of claim 1, wherein the battery is a lithium-ion battery.