CN210156498U

CN210156498U - Cylindrical battery

Info

Publication number: CN210156498U
Application number: CN201920600062.4U
Authority: CN
Inventors: 向德波; 刘熙林; 张广明; 赵光宇; 孙伟
Original assignee: Tianneng Shuai Fude Energy Co Ltd
Current assignee: Tianneng Shuai Fude Energy Co Ltd
Priority date: 2019-04-28
Filing date: 2019-04-28
Publication date: 2020-03-17
Anticipated expiration: 2029-04-28

Abstract

The utility model discloses a cylinder type battery belongs to energy storage technical field. Cylindrical battery, including shell, electric core and block, electric core is convoluteed by positive pole piece, diaphragm, negative pole piece and forms, and positive pole utmost point ear and negative pole utmost point ear have been welded respectively to the tip of positive pole piece and negative pole piece, and the tip and the block of positive pole utmost point ear are connected, and the tip and the shell wall connection of negative pole utmost point ear, positive pole utmost point ear, negative pole utmost point ear except the tip of being connected with block, shell, all the other parts that expose electric core all are wrapped up by insulating macromolecular material sleeve pipe, and insulating macromolecular material sleeve pipe bonds on utmost point ear through self contractility. The insulating high polymer material sleeve is bonded with the pole lug in a thermal contraction mode and the like, the combination is tight and firm, the pole lug cannot fall off under the action of external force or under the long-term soaking condition of electrolyte, the safety and reliability are greatly improved, and the safety problems of battery self-discharge, thermal runaway and the like caused by the fact that the pole lug is in direct contact with the shell and metal chips at the pole lug are fundamentally solved.

Description

Cylindrical battery

Technical Field

The utility model relates to an energy storage technology field, concretely relates to cylinder type battery.

Background

The cylindrical lithium ion battery mainly comprises a shell, a cap, a positive plate, a negative plate, a diaphragm, an upper gasket, a lower gasket and electrolyte, and specifically comprises the steps of welding lugs on the positive and negative plates, wrapping high-temperature adhesive paper, winding the positive and negative plates into a cylindrical shape by separating the positive and negative plates by the diaphragm paper, placing the upper and lower gaskets, then placing the upper and lower gaskets into a steel shell, welding the cap, injecting the electrolyte, and sealing and forming.

The lithium ion battery is widely applied to markets of digital products, electric tools, electric automobiles, energy storage and the like due to high energy density, and particularly shows well-jet type growth in the field of electric automobiles in recent years. However, the safety performance of the lithium ion battery is always troubled by people, and the unsafe reasons are various, including that the battery is intrinsically unsafe, the battery manufacturing process is not controlled in place, the battery using process is not safe, and the like.

The fact that the tabs are in direct contact with the housing or in contact with the housing through metal scraps is an important cause of short circuit and potential safety hazard of the battery, and is particularly obvious in cylindrical batteries. When cylindrical 18650 electric cores such as large self-discharge or short circuit are dissected and analyzed, the situation that the lugs are not wrapped by high-temperature adhesive paper and slight blacking marks appear at the vicinity of the welding cap of the positive lug can be often found through close observation after the cap is uncovered, so that the safety has a serious problem. The high temperature that produces when the short circuit is serious can lead to the thermal expansion internal combustion, makes the inside electrolyte of electric core take place to decompose, destroys the inside electrochemistry performance of electric core to because the decomposition produces a large amount of gas, lead to interior pressure too big can cause the explosion, the inside positive negative pole material of battery contacts the short circuit each other and arouses the spark, serious consequences such as explosion-proof block emits gas and flame, the main reason is because to not wrapping the utmost point ear when pasting anodal ear adhesive tape, seals the crooked back and contacts with side steel casing (negative pole) and arouses the short circuit of anodal ear.

The cylinder battery passes through utmost point ear rubberizing tape mode and realizes the isolation of utmost point ear and electric core, and this kind of mode has very big defect: the adhesive tape is not firmly bonded with the tab, is easy to fall off, is easy to separate under the conditions of long-term soaking of electrolyte and external force vibration, causes the tab to contact with the shell, and causes the self-discharge or thermal runaway phenomenon of the battery.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a can effectively keep apart utmost point ear and conch wall, the cylinder type battery of electric core, ensure the security of battery.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the utility model provides a cylinder type battery, includes shell, electric core and block, electric core is convoluteed by positive pole piece, diaphragm, negative pole piece and forms, positive pole utmost point ear and negative pole utmost point ear have been welded respectively to the tip of positive pole piece and negative pole piece, the tip and the block of positive pole utmost point ear are connected, the tip and the shell inner wall connection of negative pole utmost point ear, positive pole utmost point ear, negative pole utmost point ear except the tip of being connected with block, shell, all the other parts that expose electric core all are wrapped up by insulating polymer material sleeve pipe, insulating polymer material sleeve pipe bonds on utmost point ear through self contractility.

The utility model discloses an insulating macromolecular material sleeve pipe is established to the cover and is wrapped up it on utmost point ear, can prevent effectively that utmost point ear and conch wall, electric core from taking place the contact and the short circuit, insulating macromolecular material sleeve pipe adopts insulating nature, the polymer that the thermal contraction nature is good, and this kind of material bonds with utmost point ear after mode shrinkage such as thermal treatment and is in the piece, and the cohesiveness is strong, does not take place to drop, and battery fail safe nature promotes by a wide margin.

Preferably, the insulating polymer material sleeve is made of one or more of ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride and polytetrafluoroethylene.

Preferably, the insulating polymer material sleeve is combined with the tab by the action of thermal shrinkage, light radiation shrinkage or electrostriction.

Preferably, the positive electrode tab is made of aluminum, and the negative electrode tab is made of copper or nickel-plated copper.

Preferably, two or more tabs of the battery cell are located on the same side of the battery cell.

The shell is made of aluminum alloy, stainless steel or plastic and the like, has certain strength and good welding performance.

Preferably, the bottom end of the insulating polymer material sleeve abuts against the end part of the battery core. Except the end part of the lug connected with the cap or the shell, the other parts exposed out of the battery core are all wrapped by the insulating polymer material sleeve.

Preferably, the height of the insulating polymer material sleeve accounts for 50-80% of the part of the positive electrode tab, which is exposed out of the cell.

The cylindrical battery is any one of secondary batteries such as a lithium ion battery, a sodium ion battery or an aluminum ion battery.

Compared with the prior art, the utility model discloses the beneficial effect who possesses:

the insulating high polymer material sleeve is bonded with the electrode lugs such as copper and aluminum through thermal contraction and the like, the combination is tight and firm, the insulating high polymer material sleeve cannot fall off under the action of external force or under the long-term soaking condition of electrolyte, the safety and reliability are greatly improved, and the safety problems of battery self-discharge and thermal runaway caused by the fact that the electrode lugs are in direct contact with the shell and metal chips at the electrode lugs are fundamentally solved.

Drawings

Fig. 1 is a schematic structural diagram of embodiment 1 of the present invention.

Fig. 2 is a schematic structural diagram of embodiment 2 of the present invention.

Detailed Description

The present invention will be further described with reference to the following embodiments.

Example 1

As shown in fig. 1, the present embodiment provides a cylindrical lithium ion battery, which includes a casing 1, a battery cell 2 and a cap 3, wherein the battery cell 2 is formed by winding a positive electrode plate, a separator and a negative electrode plate to form a cylindrical shape and is placed inside the casing 1, and the cap 3 is hermetically disposed on the top of the casing 1. Specifically, the outer diameter of the cap 3 is 17.7mm, the outer shell 1 is a steel shell, and the outer diameter is 18.25 mm.

The end parts of the positive pole piece and the negative pole piece are respectively welded with a positive pole tab 4 and a negative pole tab 5, the widths of the positive pole tab 4 and the negative pole tab 5 are both 4mm, the positive pole tab 4 is made of aluminum, and the negative pole tab 5 is made of nickel-plated copper; anodal utmost point ear 4 and negative pole utmost point ear 5's length all is greater than the width of anodal pole piece and negative pole piece, two utmost point ears expose the portion and are located the both ends of electric core 2 respectively, anodal utmost point ear 4's tip and block 3 are connected, negative pole utmost point ear 5's tip and 1 interior wall connection of shell, anodal utmost point ear 4, negative pole utmost point ear 5 except with block 3, the tip that shell 1 is connected, all the other parts that expose electric core all are wrapped up by insulating macromolecular material sleeve pipe 6, insulating macromolecular material sleeve pipe 6 bonds on utmost point ear through self contractility.

Specifically, the length of the part of the two electrode lugs exposed out of the battery core is 16mm, the bottom end of the insulating polymer material sleeve is abutted against the end part of the battery core, the height of the insulating polymer material sleeve is 10mm, the insulating polymer material sleeve is made of PVC, and the polymer sleeve is subjected to heat shrinkage at a high temperature of 80 ℃ to tightly wrap the surfaces of the positive electrode lug and the negative electrode lug.

Example 2

The present embodiment provides a cylindrical lithium ion battery, which has a structure substantially the same as that of embodiment 1, and is different from embodiment 1 in that an outer diameter of a cap 3 is 25.5mm, an outer diameter of a housing 1 is 26.5mm, wherein a positive electrode tab is of a bipolar tab structure, and each positive electrode tab is wrapped by an insulating polymer sleeve.

The insulating polymer material sleeve is made of polytetrafluoroethylene, and the polymer sleeve is subjected to thermal shrinkage at the high temperature of 90 ℃ to tightly wrap the surface of the aluminum lug.

Comparative example 1

In the prior art, a cylindrical battery is directly adhered to the surface of a lug through an adhesive tape so as to prevent the lug from contacting with a shell wall.

Application example

The cylindrical lithium ion batteries (injected but not formed) prepared in examples 1 and 2 and comparative example 1 were placed in an oven at 100 ℃ for 7 days, and then the batteries were disassembled to find that the insulating polymer sleeves of examples 1 and 2 were still tightly wrapped on the tabs, while the adhesive tape of comparative example 1 was loose and nearly peeled off.

The above description is only for the preferred embodiment of the present invention and should not be construed as limiting the present invention, and any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention are all included within the protection scope of the present invention.

Claims

1. The utility model provides a cylinder type battery, includes shell, electric core and block, electric core is convoluteed by positive pole piece, diaphragm, negative pole piece and forms, positive pole utmost point ear and negative pole utmost point ear have been welded respectively to the tip of positive pole piece and negative pole piece, the tip and the block of positive pole utmost point ear are connected, the tip and the shell inner wall connection of negative pole utmost point ear, its characterized in that, positive pole utmost point ear, negative pole utmost point ear except with the tip of block, shell inner wall connection, all the other parts that expose electric core all are wrapped up by insulating polymer material sleeve pipe, insulating polymer material sleeve pipe bonds on utmost point ear through self contractility.

2. The cylindrical battery as claimed in claim 1, wherein the insulative polymer material bushing is combined with the tab by thermal contraction, optical contraction or electrical contraction.

3. The cylindrical battery according to claim 1, wherein the positive electrode tab is made of aluminum, and the negative electrode tab is made of copper or nickel-plated copper.

4. The cylindrical battery as claimed in claim 1, wherein the bottom end of the insulating polymer material sleeve abuts against the end of the cell.

5. The cylindrical battery as claimed in claim 1 or 4, wherein the height of the insulating polymer material sleeve is 50-80% of the exposed cell part of the tab.

6. The cylindrical battery according to claim 1, wherein the cylindrical battery is a lithium ion battery, a sodium ion battery or an aluminum ion battery.