CN102903866A

CN102903866A - Lithium ion battery

Info

Publication number: CN102903866A
Application number: CN201110209136XA
Authority: CN
Inventors: 周富华
Original assignee: XIANGTAN YINHE NEW ENERGY CO Ltd
Current assignee: XIANGTAN YINHE NEW ENERGY CO Ltd
Priority date: 2011-07-25
Filing date: 2011-07-25
Publication date: 2013-01-30
Anticipated expiration: 2031-07-25
Also published as: CN102903866B

Abstract

The present invention discloses a lithium ion battery, which comprises a battery upper cover (2) adopted as a battery positive electrode, a battery case (3) adopted as a battery negative electrode, and a winding-type battery core arranged inside the battery case, wherein a bidirection safety valve (1) is arranged on the battery upper cover (2), can be used for liquid injection during a battery production process, and can be automatically sealed after liquid injection, such that characteristics of pressure relief and explosion prevention are provided when internal pressure of the battery is excessively high, and the sealing state can be restored again when the internal pressure of the battery is restored to the normal state.

Description

A kind of lithium ion battery

Technical field

The present invention relates to field of batteries, particularly relate to the lithium ion battery that a kind of device has bidirectional relief valve.

Background technology

Compare with the battery of the other types such as plumbic acid, NI-G, ni-mh, lithium ion battery has that specific capacity is large, operating voltage is high, has extended cycle life, volume is little, the advantage such as lightweight, not only be used widely at portable electric appts, and being widely used in electric automobile, electric bicycle and electric tool etc. aspect medium-sized electrical equipment, lithium-ion-power cell especially wherein is the main direction of each macrocell producer development at present.But lithium ion battery in use when being subject to short circuit, high heat, overcharging or during the affecting of the abnormal factors such as overdischarge, inside battery easily has gases at high pressure to produce, will cause the distortion of battery container even produce the danger of blast.Therefore, for the lithium ion battery of the hard shells such as metal, for the potential safety hazard of stopping to raise and cause because of inner pressure of battery in the battery use procedure, must be at the quick-fried device of battery device security protection.Safe explosion-proof device commonly used mainly contains two kinds of forms on the lithium ion battery at present:

A kind of is the indentation that has certain depth in the processing of the metal shell surface of battery, and when inner pressure of battery was elevated to a certain degree, the indentation step-down of can automatically breaking was to prevent the battery explosion.This indentation explosion-protection equipment is difficult to accurate control because of its degree of depth, and the stress consistency at indentation position is relatively poor, is difficult to guarantee its action message.

Another kind is at the explosionproof hole of battery metal housing cover plate processing one deck rupture pressure disc, and when inner pressure of battery was elevated to a certain degree, the rupture pressure disc step-down of can automatically breaking reached the purpose that prevents the battery explosion.But, not only high to the production equipment requirement at cover plate explosionproof hole processing rupture pressure disc, and because processing technology is complicated, and increase cost.In addition, rupture pressure disc also can't guarantee constant fracture pressure, still has certain potential safety hazard.

And above-mentioned two kinds of lithium ion battery safety devices all can not recover after indentation or rupture pressure disc break again, make whole battery failure and scrap.

In addition, lithium ion battery needs to inject electrolyte to inside battery in process of production, generally is to open a through hole at the loam cake of battery, also will be again with its shutoff after having annotated electrolyte, and fluid injection operation more complicated.

Summary of the invention

Problem to be solved by this invention is the defective that overcomes above-mentioned prior art, provide a kind of device that the lithium ion battery of bidirectional relief valve is arranged, this bidirectional relief valve in the battery production process, be used for fluid injection and after fluid injection self-closed, when inner pressure of battery is too high, can also can when inner pressure of battery recovers normal, again recover sealing state by pressure-relief explosion-proof in the use.

Technical scheme of the present invention is: the present invention includes cell cover as anode, as the battery container of battery cathode with place takeup type battery core in the battery container, a bidirectional relief valve that has fluid injection and explosion prevention function concurrently is set on the cell cover.

Described bidirectional relief valve comprises valve body, bonnet, poppet shaft and is sleeved on spring sealed assembly on the poppet shaft, described bonnet covers for described valve body is fixedly installed on the lithium ion battery, described valve body outer ring suit sealing ring, described poppet shaft is installed on described body cavity, described poppet shaft one end from described valve body lower portion stretch to the battery cover inboard, the other end stretches out from described bonnet top, described poppet shaft can be up and down and will be made the channel seal of inside battery and exterior on described valve body and the described bonnet or open by described spring sealed assembly.

Described spring sealed assembly comprises back-moving spring, interior sealing gasket, upper spring seat, the external seal pad, pressure spring, lower spring cup, described back-moving spring is clipped between the shoulder of the described poppet shaft upper limit shaft shoulder and described body cavity, described upper spring seat, described pressure spring and described lower spring cup are set on the described poppet shaft and are in described valve body lower portion, be provided with gas channel between described upper spring seat inner surface and the described poppet shaft outer surface, described interior sealing gasket fixed cover is loaded on the described poppet shaft and is suitable with described upper spring seat inner surface top, and described external seal pad is fixedly set in described upper spring seat outer surface of upper and suitable with described body cavity lower end.

The sealing contact surface of described interior sealing gasket is the arc surface of revolution, and described upper spring seat inner surface top is the taper surface of revolution.

Described body cavity lower end and described external seal pad outer surface are the taper surface of revolution.

Described battery core comprises positive plate, negative plate, barrier film, anode collection plate, negative pole currect collecting plate, after described positive plate and described negative plate separate winding shaping by described barrier film, top connects described anode collection plate, the bottom connects described negative pole currect collecting plate, described anode collection plate contacts with described cell cover, between described cell cover and the described battery container, be provided with insulating washer between described anode collection plate and the described battery container, described negative pole currect collecting plate contacts with described battery container inner bottom part.

The invention has the beneficial effects as follows: the present invention arranges a bidirectional relief valve that has fluid injection and explosion prevention function concurrently at cell cover, this bidirectional relief valve in the battery production process, be used for fluid injection and after fluid injection self-closed, when inner pressure of battery is too high, can also can when inner pressure of battery recovers normal, again recover sealing state by pressure-relief explosion-proof in the use; The poppet shaft of bidirectional relief valve of the present invention can be up and down in valve body, can will make the channel seal of inside battery and exterior on valve body and the bonnet or open under the effect of spring sealed assembly, to realize the effect of corresponding fluid injection and exhaust, compact conformation is installed simple; Back-moving spring so that spring sealed assembly automatically resets behind battery liquid-filling with outer closure in the battery, timely exhaust decompression when pressure spring can make cell internal pressure too high, function with battery anti-explosion, and when cell internal pressure reduces, in time recover sealing state.

Description of drawings

Fig. 1 is structural representation of the present invention;

Fig. 2 is the structural representation of bidirectional relief valve of the present invention;

Fig. 3 is the A-A cutaway view among Fig. 2;

Fig. 4 is the structural representation of the present invention's bidirectional relief valve when battery liquid-filling;

Fig. 5 is the structural representation of the present invention's bidirectional relief valve when the battery releasing pressure automatically.

Embodiment

Below in conjunction with accompanying drawing embodiments of the invention are done concrete detailed description the in detail.

As shown in Figure 1, comprise cell cover 2 as anode, as the battery container 3 of battery cathode with place takeup type battery core in the battery container 3, battery core comprises positive plate 4, negative plate 5, barrier film 6, anode collection plate 7, negative pole currect collecting plate 8.After positive plate 4 separates winding shaping with negative plate 5 by barrier film 6, top connects anode collection plate 7, the bottom connects negative pole currect collecting plate 8, anode collection plate 7 contacts with described cell cover 2, be provided with insulating washer 9 between cell cover 2 and the battery container 3, be provided with insulating washer 10 between anode collection plate 7 and the battery container 3, negative pole currect collecting plate 8 contacts with battery container 3 inner bottom parts; Cell cover 2 and anode collection plate 7 middle parts arrange the hole that the battery inside and outside is communicated, an idle two-way safety valve 1 in the hole, this bidirectional relief valve 1 in the battery production process, be used for fluid injection and after fluid injection self-closed, when inner pressure of battery is too high, can also can when inner pressure of battery recovers normal, again recover sealing state by pressure-relief explosion-proof in the use.

Such as Fig. 2, shown in Figure 3, bidirectional relief valve 1 comprises valve body 11, bonnet 12, poppet shaft 13 and is sleeved on spring sealed assembly on the poppet shaft 13, and spring sealed assembly comprises back-moving spring 15, interior sealing gasket 16, upper spring seat 17, external seal pad 18, pressure spring 19, lower spring cup 20.Valve body 11 outer rings suit sealing ring 14, valve body 11 is fixedly installed in lithium ion battery loam cake 2 middle parts by bonnet 12, and valve body 11 and bonnet 12 inner chambers are provided with the passage that makes inside battery and exterior; Poppet shaft 13 can be installed on the inner chamber of valve body 11 up and downly, and poppet shaft 13 1 ends stretch to the battery cover inboard from valve body 11 bottoms, the other end stretches out from bonnet 12 tops; Back-moving spring 15 is clipped between the shoulder of the poppet shaft 13 upper limit shaft shoulders 131 and valve body 11 inner chambers; Upper spring seat 17, pressure spring 19 and lower spring cup 20 are set on the poppet shaft 13 and are in valve body 11 bottoms, be provided with gas channel between upper spring seat 17 inner surfaces and poppet shaft 13 outer surfaces, interior sealing gasket 16 fixed covers are loaded on the poppet shaft 13 and are suitable with upper spring seat 17 inner surface tops, the sealing contact surface of interior sealing gasket 16 is the arc surface of revolution, upper spring seat 17 inner surface tops are the taper surface of revolution, external seal pad 18 is fixedly set in upper spring seat 17 outer surface of upper, and the outer surface of external seal pad 18 is the taper surface of revolution suitable with the taper surface of revolution of valve body 11 inner chamber lower ends.

Under normal circumstances, sealing ring 14 seals mutually with the installing hole inner chamber of cell cover 2 one, and interior sealing gasket 16 seals mutually with upper spring seat 17 inner surface tops, and external seal pad 18 seals mutually with valve body 11 inner chamber lower ends, with the channel enclosed of inside battery with the outside.

When battery liquid-filling, as shown in Figure 4, under the effect of special-purpose liquid-injection equipment, press down poppet shaft 13, back-moving spring 15 is compressed, poppet shaft 13 and interior sealing gasket 16, upper spring seat 17, external seal pad 18, pressure spring 19, lower spring cup 20 move down together, external seal pad 18 is separated with valve body 11 lower ends and forms the gap, electrolyte enters inside battery from valve body 11 inner chambers through this passage, when fluid injection is finished, poppet shaft 13 moves up under back-moving spring 15 effect, and external seal pad 18 seals with valve body 11 inner chamber lower ends and mutually with self-closed inside and outside the battery.

In the battery use procedure, when cell internal pressure acquires a certain degree, as shown in Figure 5, pressure spring 19 is made lower compression at the pressure of inside battery, interior sealing gasket 16 is with moving on the poppet shaft 13, make between upper spring seat 17 and the interior sealing gasket 16 and form the gap, the gas of inside battery enters valve body 11 inner chambers from being provided with gas channel between upper spring seat 17 inner surfaces and poppet shaft 13 outer surfaces through this gap, thereby discharge the purpose that outside batteries reaches safety relief, when cell internal pressure reduces, pressure spring 19 resets and promotes lower spring cup 20, and poppet shaft 13 just moves down the compression upper spring seat with interior sealing gasket 16, again forms sealing state.

Claims

1. lithium ion battery, comprise cell cover (2) as anode, as the battery container (3) of battery cathode with place takeup type battery core in the battery container (3), it is characterized in that: a bidirectional relief valve (1) that has fluid injection and explosion prevention function concurrently is set on the described cell cover (2).

2. lithium ion battery according to claim 1, it is characterized in that: described bidirectional relief valve (1) comprises valve body (11), bonnet (12), poppet shaft (13) and be sleeved on spring sealed assembly on the poppet shaft (13), described bonnet (12) is used for described valve body (11) is fixedly installed in lithium ion battery loam cake (2), described valve body (11) outer ring suit sealing ring (14), described poppet shaft (13) is installed on described valve body (11) inner chamber, described poppet shaft (13) one ends stretch to the battery cover inboard from described valve body (11) bottom, the other end stretches out from described bonnet (12) top, and described poppet shaft (13) can be up and down and will be made the channel seal of inside battery and exterior on described valve body (11) and the described bonnet (12) or open by described spring sealed assembly.

3. lithium ion battery according to claim 2, it is characterized in that: described spring sealed assembly comprises back-moving spring (15), interior sealing gasket (16), upper spring seat (17), external seal pad (18), pressure spring (19), lower spring cup (20), described back-moving spring (15) is clipped between the shoulder of described poppet shaft (13) the upper limit shaft shoulder (131) and described valve body (11) inner chamber, described upper spring seat (17), described pressure spring (19) and described lower spring cup (20) are set in described poppet shaft (13) upward and are in described valve body (11) bottom, be provided with gas channel between described upper spring seat (17) inner surface and described poppet shaft (13) outer surface, it is upper and suitable with described upper spring seat (17) inner surface top that described interior sealing gasket (16) fixed cover is loaded on described poppet shaft (13), and described external seal pad (18) is fixedly set in described upper spring seat (17) outer surface of upper and suitable with described valve body (11) inner chamber lower end.

4. lithium ion battery according to claim 3, it is characterized in that: the sealing contact surface of described interior sealing gasket (16) is the arc surface of revolution, described upper spring seat (17) inner surface top is the taper surface of revolution.

5. lithium ion battery according to claim 3, it is characterized in that: described valve body (11) inner chamber lower end and described external seal pad (18) outer surface are the taper surface of revolution.

6. according to claim 1 to 5 described any lithium ion batteries, it is characterized in that: described battery core comprises positive plate (4), negative plate (5), barrier film (6), anode collection plate (7), negative pole currect collecting plate (8), after described positive plate (4) separates winding shaping with described negative plate (5) by described barrier film (6), top connects described anode collection plate (7), the bottom connects described negative pole currect collecting plate (8), described anode collection plate (7) contacts with described cell cover (2), between described cell cover (2) and the described battery container (3), be provided with insulating washer between described anode collection plate (7) and the described battery container (3), described negative pole currect collecting plate (8) contacts with described battery container (3) inner bottom part.