CN203589159U

CN203589159U - External formation groove of lithium ion battery

Info

Publication number: CN203589159U
Application number: CN201320611642.6U
Authority: CN
Inventors: 王化胜; 赵海刚
Original assignee: Shandong Realforce Group New Energy Science And Technology Co Ltd
Current assignee: Shandong Realforce Group New Energy Science And Technology Co Ltd
Priority date: 2013-10-03
Filing date: 2013-10-03
Publication date: 2014-05-07
Anticipated expiration: 2023-10-03

Abstract

The utility model provides an external formation groove of a lithium ion battery. The external formation groove consists of a formation groove shell 108 and a formation groove cover 203, wherein the formation groove cover 203 is provided with a positive terminal 204, a negative terminal 205, a liquid injection hole 201 and a pneumatic control tube 202, the formation groove shell 108 is provided with a positive electrode plate 105 and a temperature control system 107, the positive electrode plate 105 is connected together with the positive terminal 204 by virtue of a lead 106, the pneumatic control tube 202 is connected with an ammonia gas source and a vacuum pump 304 by virtue of an ammonia preparation system 3021 and a vacuum tube 305 on a purification system 301, and the vacuum tube is provided with a pressure regulating valve 303. Compared with the prior art, the groove has the advantages that in the formation process, the mode that the positive electrode is sacrificed is adopted, a lithium source for forming an SEI film is provided for an exposed battery cell to be formed, and lithium reserved in a carbon layer ensures the stability of negative electrode materials; according to the scheme, the positive lithium source in the battery cell is scarce in loss, so that the primary coulombic efficiency is improved, and the energy capacity of the battery is improved.

Description

The outer electrolytic bath of a kind of lithium ion battery

Technical field

The utility model belongs to lithium ion battery and manufactures field, and a kind of outer electrolytic bath of lithium ion battery is specifically provided.

Background technology

In the manufacture process of lithium ion battery, changing into is the process of charging for the first time of lithium ion battery, its effect is to activate lithium ion battery material, make it to have the character of chemical power source, in the formation process of lithium ion battery, electrolyte and negative material react in aspect between solid liquid phase, form one deck solid electrolyte interface film (SEI film), SEI film has solid electrolyte character, is electronic body, and lithium ion but can pass through; And SEI film anticathode material can produce protective effect; make material structure be not easy avalanche; increase the cycle life of electrode material; but can consume a part of lithium ion in the forming process of SEI film; and when electric discharge, for the stability of negative pole carbon-based material, common controlled discharge voltage; to guarantee that a part of lithium stays in carbon-coating, this part lithium is also irreversible lithium.Therefore cause battery cycle efficieny (have even lower than 80%) on the low side first, limited the lifting of lithium ion battery energy density.

In order to improve lithium ion battery reversible capacity and first charge-discharge efficiency, the method adopting mainly contains: doping or the redox processing to charcoal material surface, by charcoal negative pole being carried out to low-level oxidation and micro-reduction in oxidation or reducing atmosphere, improve surface functional group and the structure of Carbon Materials, thereby reach the object of improving first charge-discharge efficiency; In addition, it is also conventional method that Carbon Materials is carried out to the coated processing in surface, adopt at the coated one deck amorphous carbon material of graphited charcoal material surface, prepare the Carbon Materials with core-shell composite structure, the good feature of utilizing amorphous carbon material and solvent compatibility is improved the charge-discharge property of carbon cathode material.

But still there is obvious shortcoming in prior art, for example, in lithium ion battery formation process, be accompanied by the formation of SEI film, can produce more gas, under capillary effect, bubble often sticks on pole piece, be difficult for discharging, the bubble between pole piece is equivalent to insulator, at the many insulating regions of the inner formation of battery core, cause each region of utmost point group to change into inhomogeneous, negative pole cannot form uniform and stable SEI film, when high current charge-discharge, may cause and analyse lithium, rouse shell etc., affect the safety of battery; And in formation process, can produce toxic gas, as these gases are not collected, process, and be directly discharged in workshop or external environment, these gases pollute the environment, and have a strong impact on worker healthy.

Changing into of lithium battery is generally independently, there is certain difference in the conditions and environment that changes into of each battery, thereby also there is certain difference in the SEI film forming, SEI film is very large on coulomb efficiency first and the cycle life impact of lithium ion battery, therefore independently change into the discreteness that scheme may expand battery performance, in order to form stable, fine and close SEI film, and be beneficial to the eliminating of formation gas, many experts have proposed that vacuum changes into or negative pressure changes into, but the battery that changes into the stage is independently, cause formation device loaded down with trivial details, wayward.

Summary of the invention

For addressing the aforementioned drawbacks,. the utility model provides a kind of lithium ion battery outer formation device, improve coulomb efficiency and the energy density first of lithium battery, form SEI film stable, that fine and close, consistency is high, improve consistency, cycle performance and the fail safe etc. of battery, and reduce the environmental pollution in production process.

For achieving the above object, the technical scheme that the utility model adopts is: described electrolytic bath covers and is provided with positive terminal, negative terminal, liquid injection hole, air pressure control valve, the other end of described air pressure control valve is connected with ammonia source and vacuum pump by the ammonia system interface processed in cleaning system and vacuum tube, is provided with pressure regulating valve on vacuum tube; Described positive terminal is connected with anode pole piece by lead-in wire, and described negative terminal is connected with the negative pole of battery core to be changed by lead-in wire, and described liquid injection hole is connected with electrolyte by liquid injection pipe.

Further, the battery core to be changed in described electrolytic bath housing stacks in parallel, between the positive pole of battery core to be changed, is provided with anode pole piece.

Further, described electrolytic bath housing is provided with temperature control system.

Compared with prior art, the utility model is in formation process, adopt the anodal mode of sacrificing, for naked battery core to be changed provides the lithium source that forms SEI film, be retained in the stability that lithium in carbon-coating has guaranteed negative material, by this programme, the anodal lithium source in battery core is not loss almost, thereby improved coulomb efficiency first, improve energy content of battery density.

The SEI film stable for forming, fine and close, consistency is high, the present invention adopts the identical condition that changes into, guarantee that every temperature, air pressure, charging and discharging currents, voltage that changes into battery core is consistent, guarantee the consistency of battery core, the mode that adopts controllable negative pressure to change into, adjustment changes into temperature, controls stability and compactness that forming current, voltage and aging condition etc. improve SEI film.

Show by experiment on the basis of same material, same process, by chemical synthesizing method of the present invention, can make coulomb efficiency first of battery core reach more than 98%, energy density can improve more than 3%.

Accompanying drawing explanation

Fig. 1, electrolytic bath structural representation.

Fig. 2, electrolytic bath housing schematic diagram.

Fig. 3, electrolytic bath lid schematic diagram.

The anodal .103 battery core negative pole to be changed .104 of 101 battery core .102 to be changed battery core to be changed battery core negative wire to be changed .105 anode pole piece .106 lead-in wire .107 temperature control system .108 electrolytic bath housing .109 electrolytic bath .201 liquid injection hole .202 air pressure control valve .203 electrolytic bath lid .204 positive terminal .205 negative terminal .206 liquid injection pipe .301 cleaning system .302 ammonia system interface processed .303 pressure regulating valve .304 vacuum pump .305 vacuum tube in figure.

Embodiment

The outer electrolytic bath of a kind of lithium ion battery, by 108 electrolytic bath housings and 203 electrolytic baths lid, formed, 203 described electrolytic baths cover and are provided with 204 positive terminals, 205 negative terminals, 201 liquid injection holes and 202 air pressure control valves, on 108 described electrolytic bath housings, be provided with 105 anode pole pieces and 107 temperature control systems, 105 anode pole pieces link together by 106 lead-in wires and 204 positive terminals, 202 described air pressure control valves are connected with ammonia source and 304 vacuum pumps by 3021 ammonia system interfaces processed and 305 vacuum tubes in 301 cleaning systems, on described vacuum tube, be provided with 303 pressure regulating valves.

Below in conjunction with embodiment, the utility model is described further: 101 battery cores to be changed are overlayed in 109 electrolytic baths by mode in parallel, between 102 battery core positive poles to be changed in the battery core stacking, be close to and place one group of 105 anode pole piece, the positive terminal 204 that 105 anode pole pieces cover with electrolytic bath by 106 lead-in wires is connected; The battery core negative pole 103 to be changed of battery core 101 to be changed is linked together by 104 battery core negative wires to be changed, as negative pole, and be connected with the negative terminal to be changed 205 of electrolytic bath lid; After wiring connects, utilize 305 vacuum pumps by 304 vacuum tubes on 202 air pressure control valves, 109 electrolytic bath sealings to be vacuumized 109 electrolytic baths, by 303 pressure regulating valves, control the pressure in 109 electrolytic baths, then by 302 ammonia system interfaces processed in 301 cleaning systems, be filled with nitrogen; Then by 201 liquid injection holes, in electrolytic bath, inject electrolyte; Then by 204 positive terminal 205 negative terminals, be connected with charging device, repeat to discharge and recharge, now, by 107 temperature control systems, control electrolytic bath temperature, until complete.

Obviously, above-described embodiment is only better embodiment of the present utility model, and any simple change of having done on this basis all belongs to protection range of the present utility model.

Claims

1. the outer electrolytic bath of a lithium ion battery, by electrolytic bath housing and electrolytic bath lid, formed, electrolytic bath described in it is characterized in that covers and is provided with positive terminal, negative terminal, liquid injection hole, air pressure control valve, the other end of described air pressure control valve is connected with ammonia source and vacuum pump by the ammonia system interface processed in cleaning system and vacuum tube, is provided with pressure regulating valve on vacuum tube; Described positive terminal is connected with anode pole piece by lead-in wire, and described negative terminal is connected with the negative pole of battery core to be changed by lead-in wire, and described liquid injection hole is connected with electrolyte by liquid injection pipe.

2. the outer electrolytic bath of a kind of lithium ion battery according to claim 1, is characterized in that the battery core to be changed in electrolytic bath housing stacks in parallel, between the positive pole of battery core to be changed, is provided with anode pole piece.