CN2754216Y

CN2754216Y - Lithium battery and structure thereof

Info

Publication number: CN2754216Y
Application number: CNU2004200940930U
Authority: CN
Inventors: 薛建军; 夏信德; 潘群生
Original assignee: Guangzhou Great Power Battery Co ltd
Current assignee: Guangzhou Great Power Energy & Technology Co Ltd
Priority date: 2004-10-14
Filing date: 2004-10-14
Publication date: 2006-01-25
Anticipated expiration: 2014-10-14

Abstract

The utility model discloses a lithium battery and a structure thereof, which belongs to the battery field, and is composed of a battery positive terminal component, a steel shell, a sealing ring, a positive electrode, a diaphragm and a negative electrode, wherein an explosion-proof structure is arranged in the battery positive terminal component, and the explosion-proof structure comprises a metal pad and an explosion-proof composite film; the explosion-proof composite membrane comprises three-layer or more than three-layer film, places positive temperature coefficient thermistor component on explosion-proof structure, has boss and sunken bottom the battery steel casing, the utility model discloses prevent safety problems such as battery weeping and corruption, inflation, short circuit effectively, can extensively be applicable to in various types of lithium cell, the specially adapted lithium/iron disulfide battery.

Description

Lithium battery and structure thereof

Technical Field

The utility model discloses lithium cell and structure thereof belongs to the battery field, especially relates to a non-aqueous electrolyte lithium cell.

Background

With the development of electronic technology and information technology, ordinary zinc-manganese batteries and alkaline-manganese batteries appear to be unable to meet the requirements of high-grade electronic equipment, especially the two requirements of high energy density and good safety performance. The lithium battery with high energy density is developed more and more rapidly in recent years, but the structure of the battery is still to be improved, and the lithium battery in the prior art has the problems of easy liquid leakage, corrosion and the like. An explosion-proof structure in a lithium battery has the defects of an explosion-proof membrane structure adopted in the prior art, on one hand, the battery leakage is caused because the sealing between the explosion-proof membrane and an internal system of the battery is not good, and on the other hand, the anti-electrolyte corrosion effect of the adopted explosion-proof membrane is poor, so that the early failure of the explosion-proof membrane is caused. Lithium batteries cause the bottom of the battery to protrude outward in case of improper use due to expansion of the internal material and increase of gas pressure, and thus cause a safety problem.

The utility model aims to avoid the weak point among the prior art, eliminate the easy weeping of lithium cell and the safety problems such as corruption, battery post-discharge inflation and short circuit, and disclose a have the inside explosion-proof structure of good security, prevent the short circuit, the high novel structure of compressive strength of battery steel casing bottom lithium cell.

The contents of the utility model

The utility model aims at reaching through following measure, it is by the positive terminal subassembly of battery, the box hat, the sealing washer, anodal, the diaphragm, the negative pole is constituteed. The battery positive terminal assembly comprises an upper cover, a positive temperature coefficient thermistor and an explosion-proof structure, wherein an insulating gasket is arranged at the bottom of the steel shell, the insulating gasket is arranged at the upper part of the steel shell, the explosion-proof structure is arranged in the battery positive terminal assembly and comprises a metal pad and an explosion-proof composite membrane; the explosion-proof composite film is composed of three or more than three layers of films, the lower layer is a polymer film material with good bonding performance with a metal pad after hot pressing, the middle layer is an aluminum foil with good sealing performance, the upper layer is a polymer film material with a protection function, a hole is formed in the metal pad, the explosion-proof composite film is bonded on the metal pad after hot pressing, the explosion-proof composite film covers the hole of the metal pad, the explosion-proof composite film cracks and leaks when the internal pressure of the battery is too high, a positive temperature coefficient thermistor element is arranged on an explosion-proof structure and used for preventing the short circuit of the battery, the thermistor is obtained by mutually hot-pressing and laminating a conductive polymer matrix and a conductive nickel-plated copper foil and is subjected to radiation crosslinking, a boss and a recess are formed in the bottom of a steel shell of the battery, the compressive strength of the bottom of the steel shell of the battery is enhanced, and the bottom expansion of the battery caused by the excessive internal pressure of the battery in the discharging process is prevented.

The utility model discloses prevented effectively that the battery from in charge-discharge process and storage process, such as battery weeping and corrosion, discharge back battery inflation, safety problems such as short circuit, improved the performance of lithium cell, can extensively be applicable to in various types of lithium cell, specially adapted lithium disulfide iron battery, the utility model provides a battery that the structure produced has good performance, especially adapted power as various consumer.

Drawings

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

Fig. 2a is a schematic diagram of the explosion-proof structure of the present invention.

Fig. 2b is an enlarged schematic view of the explosion-proof composite membrane of the present invention.

Fig. 3 is a schematic diagram of the bottom enlarged structure of the steel shell of the present invention.

Fig. 4 is a schematic diagram of the thermistor structure of the present invention.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings.

As shown in the attached figure 1, the utility model discloses it comprises battery positive terminal subassembly, steel-shelled 3, sealing washer 4, anodal 9, diaphragm 8, negative pole 10. The battery positive terminal component comprises an upper cover 1, a positive temperature coefficient thermistor 2 and an explosion-proof structure, wherein an insulating gasket 11 is arranged at the bottom 12 of a steel shell, an insulating gasket 5 is arranged at the upper part of the steel shell, the explosion-proof structure is arranged in a positive terminal component of the battery and consists of a metal pad 6 and an explosion-proof composite film 7, the explosion-proof composite film consists of three or more layers of films, the lower layer is a polymer film material which has good bonding performance with the metal pad 6 after hot pressing, the middle layer is an aluminum foil with good sealing performance, the upper layer is a polymer film material with a protection function, the thermistor is arranged on the explosion-proof structure, the edge of the metal pad is folded and pressed on the explosion-proof composite film, the thermistor element 2 is arranged on the explosion-proof structure and is placed on the edge of the metal pad, the edge of the battery upper cover is pressed on the edge of the thermistor element to prevent the short circuit, and the thermistor element 2 is obtained by mutually hot pressing and crosslinking of a conductive polymer matrix and a conductive nickel-plated copper foil. In order to prevent the bottom of the battery from expanding due to the excessive internal pressure of the battery after the discharge process of the battery, the center of the bottom 12 of the steel shell of the battery is provided with a concave boss so as to strengthen the compressive strength of the bottom of the steel shell of the battery.

As shown in the attached

drawings

2a and 2b, the utility model discloses an explosion-proof structure bonds after passing through the hot pressing on metal pad 6 and has explosion-proof composite membrane 7, and explosion-proof composite membrane comprises the film of three-layer, and the lower floor has the polymer film material of good adhesion property with the metal after being the hot pressing, and the centre is the aluminium foil that has good sealing performance, and the upper strata is the polymer film material that has protect function. There is a hole on metal pad 6, bonds on metal pad 6 after the hot pressing of explosion-proof composite membrane, and explosion-proof composite membrane covers on metal pad 6's hole, and the edge of metal pad is folded back and is pressed on explosion-proof composite membrane, and explosion-proof composite membrane splits when battery internal pressure is too high, loses heart through the hole on metal pad 6.

As shown in the attached figure 3, the utility model discloses there is boss 12b at battery box hat bottom 12 center, has annular concave station 12a at battery box hat bottom, strengthens the compressive strength of battery box hat bottom.

As shown in the attached figure 4, the utility model discloses be provided with thermistor component 2 in the positive terminal subassembly, prevent the battery short circuit, thermistor 2 is by conducting polymer base member 2b and the mutual hot pressing coincide of conductive nickel-plated copper foil 2a, and the conducting polymer base member comprises polyolefin and carbon black are mixed and are constituteed to obtain through the radiation crosslinking.

Claims

1. A lithium battery and its structure, it is the positive terminal assembly of the battery, the steel casing, the seal ring, the positive pole, the diaphragm, the negative pole makes up, its characteristic is to have explosion-proof structure in the positive terminal assembly of the battery, the explosion-proof structure includes metal pad and explosion-proof complex film, there is a hole on the metal pad, the explosion-proof complex film bonds on the metal pad, the explosion-proof complex film covers on the hole of the metal pad, there are bosses and sunken in the bottom of the battery steel casing, place the positive temperature coefficient thermistor component on the explosion-proof structure.

2. The lithium battery and its structure as claimed in claim 1, wherein the explosion-proof composite film is composed of three or more layers of thin films, the lower layer is a polymer thin film material, the middle layer is an aluminum foil, and the upper layer is a polymer thin film material.

3. The lithium battery and its structure as claimed in claim 1, wherein the battery steel can has a boss at its bottom center and a ring-shaped recess at its bottom.

4. The lithium battery and its structure as claimed in claim 1, wherein the edge of the metal pad is folded and pressed on the explosion-proof composite film, the thermistor element is placed on the edge of the metal pad, and the edge of the upper cover of the battery is pressed on the edge of the thermistor element.

5. The lithium battery and its structure as claimed in claim 1, wherein the thermistor is laminated by hot pressing a conductive polymer matrix and a conductive nickel-plated copper foil to each other.

6. The lithium battery and its structure as claimed in claim 2, wherein the explosion-proof composite film is composed of three layers, the lower layer is a polymer film material having good adhesion with the metal pad after hot pressing, the middle layer is an aluminum foil having good sealing performance, and the upper layer is a polymer film material having a protective function.