CN2749063Y

CN2749063Y - Cylindrical Li-ion secondary battery

Info

Publication number: CN2749063Y
Application number: CNU2004201021632U
Authority: CN
Inventors: 刘卫平; 何昱臣; 彭高平
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2004-11-29
Filing date: 2004-11-29
Publication date: 2005-12-28
Anticipated expiration: 2014-11-29

Abstract

The utility model discloses a cylindrical Li-ion secondary battery, which comprises a battery core, a cylindrical casing (10) and a covering cap, wherein the casing is sealed by the covering cap; the battery core is contained in the cylinder casing which is sealed; the covering cap comprises a sealing ring (8), a lower cover (6), a PTC element (4) and an upper cover (2), and the sealing ring (8), the lower cover (6), the PTC element (4) and the upper cover (2) are connected; the lower cover is provided with a liquid filling hole (60); the covering cap is also provided with a plugging member (12) of the liquid filling hole, and the plugging member (12) is sealed on the liquid filling hole (60). Adopting the structure and changing the operation of production process, the plugging member (12) of the liquid filling hole can be rapidly used for sealing after liquid filling, which effectively controls that moisture enters a battery in environment and eliminates the influence of water; environment moisture after liquid filling does not require too much, which can reduce brought by environment, can reduce cost pressure brought by governing environment and can rapidly improve production yield.

Description

Cylindrical lithium ion secondary battery

[technical field]:

The utility model relates to a kind of cylindrical lithium ion secondary battery.

[background technology]:

Along with the fast development of IT industry, desktop computer has turned to the notebook computer of light and handy portable band, and the digital product of small volume and less weight of all kinds has also all replaced traditional product like rain the back spring bamboo as digital camera, video camera etc.And all being chargeable chemical cell, these Related product power resources (mainly use column lithium ion battery such as circular 1865 types etc., advantage is that circular batteries is long-pending littler than square cell body, assembling making aspect), and demand cumulative year after year, yet the quality of battery directly influences the performance of this product, therefore the performance of these products has been subjected to some restrictions of battery again conversely, accelerates to develop the special concern that the high performance battery that especially can grow the circulation quick charge has caused domestic and international battery producer.

As the used battery of the said goods, compare with traditional lead-acid battery, Ni-MH battery, paid much attention to by series of advantages so that its high-energy, high power, long-life, operating voltage height, fail safe be good etc. for column lithium ion battery, obtained fast development, the used chemical energy source of digital product all is lithium ion battery basically.

Column lithium ion battery is the same with the lithium ion battery of other shapes, is made up of shell, electric core, block.Shell is circular box hat, and electric core is positive active material after being to use the composite oxides of lithium and transition metal, and carbon-based material is as negative electrode active material.Lithium ion is deviate from by electrolyte, barrier film to embed negative pole by positive pole during charging, and lithium ion is deviate from by electrolyte, barrier film to be embedded into positive pole by negative pole during discharge.Block is made of sealing ring, lower cover, PTC, loam cake disjunctor.

Column lithium ion battery also will carry out spot welding anodal block, fluid injection, seal these important steps in manufacturing process.At present column lithium ion battery all be adopt batching, slurry, film-making, coiling, spot welding negative pole nickel strap in the box hat bottom, again put into cone spacer, pull out straight aluminium pole ears, jet-bedding, put sealing ring, positive pole is drawn in spot welding (anodal aluminium pole ears is welded in down covers), and be moved out to outside the battery port, be that sealing ring and lower cover comprise that aluminium pole ears moves on to the battery port outside together, ability fluid injection like this, because be that point has welded earlier, anodal aluminium pole ears point under covered, the centre is with sealing ring, and this mode is to be shifted out the ability fluid injection to it.

If not first spot welding aluminium pole ears, first fluid injection spot welding again; Then drop into too big, rate of finished products low and more difficult operation and control, this be because: 1, be that the big bore φ 18mm as 1865 types of battery oral area are that the fluid injection bore is also big, after taking off, fluid injection comes the words of spot welding again, time is long, moisture just enters in the electric liquid (electric liquid water absorbing capacity is fast), this to requirement of Environmental Water content just higher 2, most importantly whole pole piece and aluminium pole ears all steep in electric liquid during fluid injection, will extract aluminium pole ears when in spot welding gives me a little, speckle with electric liquid on the aluminium pole ears, be exposed in the air also easily oxidation, there is electric liquid on the surface and oxide is arranged with regard to bad spot welding, even wiped earlier

Surface electrical liquid, also no matter be ultrasonic spot welding or current point welding machine point, effect is all descended, it all is the difficult point jail, explode fire, easily come off, and the aluminium utmost point is also easily broken, rate of finished products is just very low, after tested, even each station has all been handled properly, qualified product also have only the qualification rate about 60%, even also can the problems such as electricity of can not filling that aluminium pole ears comes off and causes occur in the use afterwards.3, operation easier is big, control moisture aspect is just more difficult, and the workman also must be for a long time under dry environment, and not having has increased indirect finished product etc. with fixed attention.

No matter above-mentioned which kind of mode, the general mode of fluid injection all needs under dry environment and the sealing fluid injection in the prior art, and sealing is to utilize to vacuumize fluid injection, and imbibition is fast like this, has guaranteed that again no moisture enters in the fluid injection process.As shown in Figure 3, it is present traditional method, jet-bedding, put sealing ring 8, spot welding and draw positive pole (with anodal aluminium pole ears on block lower cover 6), and be moved out to the battery port outside, in sealer, seal fluid injection, again lower cover 6 be inserted in and put in the battery port in the sealing, put PTC4 and loam cake 2 in last adding again.This process must be implemented under dry environment.

Yet the problem that above-mentioned making exists is, this capping structure in spot welding, fluid injection to sealing, quite high to environmental requirement, promptly require Environmental Water content below 1PPM cause moisture to enter electrolyte because this technology takes to grow; Must under dry environment, could produce, the precision of liquid-injection equipment and the requirement of filling head are also very special, these mechanisms must comprise that aluminium pole ears moves on to the better fluid injection of battery port outside together to sealing ring and lower cover, to sealing, the especially filling head of fluid injection machine making require just highly, a mouthful big filling head also wants big, because will wrap oral area entirely, sealing difficulty is also big, and cost of manufacture also will increase greatly, also is unfavorable for industrialization.General processing mode is now: be to adopt open type fluid injection several times back and forth under dry environment, a plurality of filling heads move around, and also need a plurality of topping-up pumps to control.Be not beneficial to industrialization, cost of manufacture is also high especially simultaneously, and manufacture craft is quite loaded down with trivial details, more is unfavorable for moisture content control, and the production process time is long.So the production of scale in enormous quantities is restricted.

As commercial product, the market consumption is big, and price too higher position has restricted its development, and inexpensive is one of its characteristic.Especially producer is exactly to improve the performance and the consistency of battery designing the design principle and the technological process of production at first deferred to when producing, makes production technology simple and reliable.Producer is very big to the input of moisture content control in process of production now, and this does not have the cost of manufacture that has increased battery with fixed attention.

[summary of the invention]:

The purpose of this utility model is exactly in order to overcome the above problems, and a kind of requirement that can reduce production environment is provided, and can enhance productivity the cylindrical lithium ion secondary battery that reduces production costs again.

For achieving the above object, the utility model proposes a kind of cylindrical lithium ion secondary battery, comprise electric core, cylindrical housings 10, block, the described housing of described cap sealed, described electric core are accommodated in the sealed described cylindrical housings, and described block comprises sealing ring 8, PTC element 4, block loam cake 2, lower cover 6, four disjunctors, described lower cover 6 is provided with liquid injection hole 60, and described block also is provided with liquid injection hole closeouts 12, is sealed on the described liquid injection hole 60.

Above-mentioned cylindrical lithium ion secondary battery, described fluid injection closeouts 12 be with can with the friction tight thin rounded flakes of described sealing ring, be arranged between described lower cover and the PTC element, and with described sealing ring tight fit.Described fluid injection closeouts 12 also can adopt the bead of salable described liquid injection hole.The sphere diameter of described bead is slightly larger than described liquid injection hole aperture.

Because adopted above scheme, compared with prior art, advantage of the present utility model is:

In column lithium ion battery is produced, adopt the utility model structure, promptly change the battery cap structure, cooperate and change the production technology operation, only under block, cover liquid injection hole of design, put into the sealing back point anodal aluminium pole ears of burn-oning at jet-bedding, in the block lower cover indentation sealing that point is welded and be pressed into fluid injection in the battery together, can block with adhesive plaster earlier rapidly after the fluid injection and be pressed into steel ball more again; Or flake aluminum is sealed liquid injection port and is sealed, control effectively in the subsequent handling that moisture enters in the battery in the environment, eliminated the influence of water, ambient moisture after the fluid injection is not made too high request, can reduce the influence that environment brings, reduce the cost pressure that the smelting environment brings, and can improve production output fast.

Owing to be provided with liquid injection hole, filling head can be fixed, corresponding filling head of topping-up pump, and the volume of filling head also diminished, and the automatically controlled part of equipment can be simplified, and fluid injection machine structure also can be simplified greatly, and sealing effectiveness improves during fluid injection.

The utility model is followed the design principle of advantages of simple, and the battery manufacturing technology is simple and reliable, and is not high to the fluid injection environmental requirement, simple in structure, is easy to realize, easy and simple to handle, cost is low.

[description of drawings]:

Fig. 1 and Fig. 2 are to use the perspective view of the utility model embodiment one

Fig. 3 is a column lithium ion battery perspective view in the prior art

Among the figure: column lithium ion battery 10, lower cover 6, thin slice 12, sealing ring 8, PTC4, loam cake 2.

[embodiment]:

Also the present invention is described in further detail in conjunction with the accompanying drawings below by specific embodiment.

As shown in Figure 1, in the usual way positive/negative plate volume is had mercy on into electrode cores after, put into column type shell 10, first spot welding negative pole nickel strap promptly fixes the negative pole nickel strap on the column type drain pan, effect is to reduce the internal resistance of cell; Put into spacer ring, and opened the hole on spacer ring, spacer ring is a circular sheet, and the main insulation buffer action that rises prevents that the long diaphragm paper that punctures of positive pole ear from causing the positive/negative plate short circuit.The perforate effect is imbibition when helping battery liquid-filling.Put into sealing ring 8 then, the effect of sealing ring is that battery plus-negative plate is separately played insulating effect again, and encased positive pole, plays sealing function between linking to each other; Again anode ear aluminium strip point is welded on the lower cover 6, its effect is to draw positive pole, lower cover 6 is provided with a liquid injection hole 60, roll lug well and will put into the battery container fluid injection more in the lump in the lower cover 6 indentation sealing circles, its effect is to dwindle liquid injection port, takes off after the fluid injection with dried cloth and wipes the residual liquid of liquid injection port, puts flake aluminum or steel ball shutoff liquid injection hole as liquid injection hole closeouts 12 rapidly, effect is to seal, do not allow moisture enter in the battery, and therefore subsequent handling is not subjected to the influence of ambient moisture.So must not control, can not influence the quality of battery to the humidity of production environment.At last PTC4 of placing (effect is an over-charge protective) and block loam cake 2 (effect is to draw positive cartridge), seal, battery completes again.As shown in Figure 2, other is operated with Fig. 1, just liquid injection hole closeouts 12 is used steel ball instead by flake aluminum, specifically be (earlier on liquid injection hole, to stick one deck adhesive plaster immediately, tear adhesive plaster more just after being pressed into steel ball, even there are some adhesive plasters to be pressed into by one of steel ball, because this adhesive plaster electricity liquid is incorrosive, also be nonreactive, can also play sealing effectiveness, guarantee that the sealing of steel ball and block is tighter.After this put into again on the stationary fixture with the sealing of steel ball shutoff liquid injection hole.

Claims

1, a kind of cylindrical lithium ion secondary battery, comprise electric core, cylindrical housings (10), block, the described housing of described cap sealed, described electric core is accommodated in the sealed described cylindrical housings, described block comprises sealing ring (8), lower cover (6), PTC element (4), loam cake (2), and four disjunctors is characterized in that: described lower cover (6) is provided with liquid injection hole (60), described block also is provided with liquid injection hole closeouts (12), is sealed on the described liquid injection hole (60).

2, cylindrical lithium ion secondary battery as claimed in claim 1 is characterized in that: described fluid injection closeouts (12) for can with the friction tight thin rounded flakes of described sealing ring, be arranged between described lower cover and the PTC element, and with described sealing ring tight fit.

3, cylindrical lithium ion secondary battery as claimed in claim 1 is characterized in that: described fluid injection closeouts (12) is a bead, is sealed in described liquid injection hole.

4, cylindrical lithium ion secondary battery as claimed in claim 3 is characterized in that: the sphere diameter of described bead is slightly larger than described liquid injection hole aperture.