CN101546849A

CN101546849A - Polymer lithium ion battery and four-step synthesis and manufacturing technology thereof

Info

Publication number: CN101546849A
Application number: CN200810102964A
Authority: CN
Inventors: 潘树明
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-03-28
Filing date: 2008-03-28
Publication date: 2009-09-30

Abstract

The invention relates to a polymer lithium ion battery and a four-step synthesis and manufacturing technology thereof. The polymer lithium ion battery comprises an anode pole shoe, a cathode pole shoe and a polymer lithium ion dielectric medium diaphragm and relates to an encapsulation manufacturing technology and a filling and solidifying manufacturing technology of the polymer lithium ion battery. The required polymer lithium ion dielectric medium diaphragm is prepared by the following steps: three monomers of hexafluoropropylene, vinylidene fluoride and methyl methacrylate which have a molar ratio of 10-30 percent, 80-50 percent and 10-20 percent and cross-linking agent are mixed and put in a vacuum sintering furnace for crosslinking to increase the mechanical temperature of the medium, the furnace is vaccumized and argon gas is led in for protection, the mixture reacts at the temperature of 60-120 DEG C for 5-15h and is evenly mixed with another polymer dielectric medium, cross-linking agent is added, cutter points and active substances are controlled by pressure to form a high-quality diaphragm, and the diaphragm, the anode pole shoe and the cathode pole shoe are prepared into a battery core which is encapsulated in a shell, filled with electrolyte and prepared into a polymer battery by sealing at 50-120 DEG C. The polymer battery has high electrical conductivity and good stability and is favorable for batch production.

Description

Polymer Li-ion battery and four-step synthesis and manufacturing technology thereof thereof

Technical field

The present invention relates to a kind of polymer Li-ion battery and manufacturing process technology thereof.

Background technology

Polymer Li-ion battery is a high-energy-density secondary cell of new generation, and it is to be born in 1994, is the battery that grows up on the liquid lithium ionic cell basis.It has following obvious advantage: 1, have longer cycle life, capacitance loss few.2, configuration design flexibly, conveniently can be used for developing ultra-thin, overlarge area battery.3, needn't use traditional diaphragm material.4, volume utilization height is than the high 10-20% of liquid lithium ion battery.5, nonflammable, security reliability is good.6, can make the battery of different shape.7, application is more extensive.8, adopt polymeric dielectric to substitute liquid dielectric solution, the electrolyte leakage problem of having avoided liquid battery to exist.

Polymer lithium is from the battery production complex process at present, and the production cost height is the key factor of puzzlement battery development.

Summary of the invention

The objective of the invention is shortcoming at the existence of polymer Li-ion battery production technology, the inventor is used in the experience that lithium ion battery is produced, and designs the production technology that a kind of production technology is simple, cost rate is high, the equipment input is little, production cost is low, safety is advanced.

The technical matters that the present invention adopts is: a kind of polymer Li-ion battery, battery are formed and are comprised negative pole, membrane layer, positive pole and electrolyte.

1. diaphragm material and manufacture craft: the steel cylinder that will be full of inert gas links to each other with the stainless steel feed pot that slurries are housed, in order to make polymeric dielectric membrane thicknesses and width controlled, by regulating the rate of outflow of the pressure control slurry in the slurry tank, remaining scraper, to add the amount of locating slurries constant, matrix with constant motion drives slurry, slit by the edge of a knife and matrix forms thickness, the certain film of width, after the drying tunnel oven dry, make volume, regulate edge of a knife slit height, thereby obtain the film of desired thickness.

The barrier film raw material: polymeric dielectric is formed polymer lithium cell diaphragm with polyethylene, polypropylene, and colloidal polymer covers or is filled in the microporous barrier.

Polymeric dielectric is that inorganic ions is dissolved in the solvent in the polymer, and polymeric dielectric is polyethylene glycol oxide, PPOX, poly-1, the 2-ethylenimine, and its structure fraction is respectively: The cross-linked polymer dielectric carries out crosslinked inhibition degree of crystallinity by adding crosslinking agent, improves dielectric mechanical strength, crosslinked method: crosslinking with radiation, chemical crosslinking, physical crosslinking.Be equipped with the cross-linked network solid electrolyte with the crosslinking with radiation legal system, guaranteeing low crosslinking degree or adopting under the flexible crosslinked condition that the segment activity can obviously not weakened, conductivity can be improved.

Another kind method is: polymeric material is that methyl methacrylate, acrylonitrile, three kinds of monomers of methacrylic acid potassium mix respectively, be that mixture is put into sintering furnace, among add crosslinking agent and carry out crosslinking agent and suppress degree of crystallinity, improve dielectric mechanical strength, will be evacuated down to 10 in the stove ^-2Pa feeds under the argon shield, at 45-90 ℃ of following chemical reaction 6-14h, and first kind of material of synthetic polymer, i.e. methyl methacrylate-methacrylic acid lithium-acrylonitrile polymer.Be that hexafluoropropylene and vinylidene, three kinds of monomers of methyl methacrylate are prepared material and put in the vacuum sintering furnace with 10-30% and 50-80%, 10-20% mole composition respectively again with biasfluoroethylene-hexafluoropropylene-methymethacrylate synthetic method, add crosslinking agent and carry out the dielectric mechanical strength of crosslinked raising, vacuum degree in the stove is extracted into 10 ^-2Pa feeds argon shield at 60-120 ℃ of following chemical reaction 5-15h, second kind of material of synthetic polymer, i.e. vinylidene one hexafluoropropylene-methylmethacrylate polymer material.Again above-mentioned first kind and second kind of polymeric material are mixed and insert in the container, add fully dissolving after the solvent.The mol ratio of first kind of each component of polymer is: 0.1≤methacrylic acid lithium≤25%, 35%≤acrylonitrile≤85%, 8%≤methyl methacrylate≤35%, contain the electrolyte that percetage by weight is 30-70% in polymer dielectric.The mass ratio of above-mentioned first kind and second kind mixing is that 2:8 is to 3:5.

The fabricating technology of polymer dielectric film is applicable to that suitability for industrialized production fresh content of the present invention also has following content:

Above-mentioned first kind and second kind of polymeric material are mixed, by Chemical Crosslinking Methods crosslinking agent is joined among copper or the stainless feed pot, control the rate of outflow of its above-mentioned mixed slurry by the pressure in the adjusting slurry, slit by the edge of a knife and matrix forms needed width, the film of thickness, this film is at drying tunnel oven dry back harvest volume.

2. the making of anode pole piece: the active material LiCoO of use ₂, LiNiO ₂, LiMn ₂O ₄, the manufacture method of these materials is identical with anode material for lithium-ion batteries, but must add chemical cross-linking agent at anode sizing agent, and addition is the 1%-0.01%. of polarization coating solid content

Active material, conductive agent such as acetylene black are mixed with the adhesive that is dissolved in N-methyl pyrrolidone (NMP) (PVDE) solution, after stirring, be made into the active material of pulpous state, be coated in the both sides of aluminium foil equably, coating layer thickness: 13-25 μ m, drying is used roll squeezer compression moulding again to remove the organic substance dispersant under nitrogen current, cuts into the positive plate of required size more on request.

3. preparation negative plate: negative material is that negative electrode active material mainly is a carbon materials, comprise native graphite, asphalt base carbon fiber etc., adhesive has the SBR latex, CMC etc. add chemical cross-linking agent at cathode size, addition is that the one thousandth of pole piece coating solid content arrives one of percentage, and solvent is NMP.The binding agent (as PVOE) of charcoal or graphite and about 10% mixed make pasty state, be coated in the Copper Foil both sides equably, after the drying, roll-in is 21-26 μ m, is cut into the negative plate of given size by necessary requirement.

4. the encapsulation fluid injection is solidified.

With above-mentioned the polymer electrolyte diaphragm of making by content of the present invention, positive plate and negative plate are made electric core, and tightly encapsulate the external packing housing, inject the electrolyte LiPF that contains liquid lithium ionic cell in electric core ₆Inject the electrolyte final vacuum and seal, under 50-120 ℃ temperature, make polymer Li-ion battery.

Prepared technology of the present invention has preparation, technology is easy, and operating environment is less demanding, and interface stability is good, and battery room temperature conductivity height is easy to realize the advantage of the extensive industrialization of producing again.

Embodiment

Embodiment 1

Methymethacrylate, methacrylic acid lithium, acrylonitrile mix by synthetic mol ratio 30%:20%:50%, join and account for overall weight 5% crosslinking agent.To mix material and add in the sintering furnace, be evacuated down to 10 ^-2Pa feeds argon shield again, is incubated 10h, synthesizing methylmethacrylate-methacrylic acid lithium-acrylonitrile polymer down at 50 ℃.

Again biasfluoroethylene-hexafluoropropylene-methyl methacrylate is prepared material by synthetic mol ratio 20%:65%:15%, add the crosslinking agent that accounts for overall weight 5% again, mix and put into vacuum sintering furnace, vacuum degree adds 10 in the stove ^-2Pa; feed argon shield; be incubated 10h down at 90 ℃; synthesizing methylmethacrylate-metering system-methacrylic acid lithium-acrylonitrile polymer material; again with above-mentioned first kind; the material of second kind of synthetic polymerization mixes by 3:7 and places among the appearance; add solvent abundant molten Jie afterwards; in polymeric dielectric, contain percetage by weight and be 50% electrolyte; the above-mentioned slurry that mixes adds among the feed pot of copper work; form the film of the size that needs by regulating the rate of outflow that pressure in the slurry controls above-mentioned mixed slurry by the edge of a knife and equipment slit, this film oven dry is rolling afterwards.

Embodiment 2:

Crosslinking agent among the embodiment 1 is accounted for overall weight 5% change 8% into, other technology, condition are consistent with example 1.

The making of positive plate: with LiCoO ₂The slurry of positive electrode adds crosslinking agent adding cross-linked dosage and is 1% of polarization coating solid content.

To mix with the adhesive PVDE solution that is dissolved in N-methyl pyrrolidone (NMP) in active material, the conductive agent acetylene, after stirring, make slurry like material, be coated in the both sides of aluminium foil equably, coating layer thickness 18 μ m, dry removing the organic substance dispersant under nitrogen current, roll squeezer compression moulding again cuts into the positive plate of regulation required size more on request.

Preparation negative plate: with native graphite, SBR latex, in cathode size, add 1% crosslinking agent that accounts for overall weight, the binding agent PVOE of graphite and 10% mixed make pasty state, be coated in the Copper Foil both sides equably, roll-in is 25 μ m after dry, is cut into the negative plate of given size by necessary requirement.

Polymeric dielectric barrier film, positive plate and negative plate that the foregoing invention content is made are made electric core and are encapsulated into housing, inject the electrolyte LiPF that contains liquid lithium ionic cell in electric core ₆, vacuum seal is made polymer Li-ion battery under 80 ℃ temperature again.

Claims

1. polymer Li-ion battery and manufacturing process technology thereof is characterized in that this fabricating technology is made up of following steps:

The barrier film manufacture technology technology of polymer Li-ion battery: polymeric material is that methyl methacrylate, methacrylic acid lithium, acrylonitrile are 0.1≤methacrylic acid lithium≤25% in molar ratio, 35%≤acrylonitrile≤85%, 8%≤methyl methacrylate≤35%, three kinds of mixing, add crosslinking agent again and account for overall weight 5%, carry out crosslinked inhibition degree of crystallinity, will be evacuated down to 10 in the stove ^-2Pa feeds under the argon shield, is incubated 6-14h, synthesizing methylmethacrylate-methacrylic acid lithium-acrylonitrile polymer down at 45-50 ℃;

Is respectively 10-30% and 50-80%, 10-20% with biasfluoroethylene-hexafluoropropylene-methymethacrylate by synthetic mol ratio, prepare and expect to mix to put into vacuum sintering furnace, add 5% the crosslinking agent account for overall weight, three kinds are evenly mixed and add in the sintering furnaces vacuum degree 10 in the stove ^-2Pa feeds under the argon shield, at 60-120 ℃ of following chemical reaction 5-15h, and synthetic biasfluoroethylene-hexafluoropropylene-methylmethacrylate polymer material;

Above-mentioned first kind and second kind of material mixing are evenly inserted again and added abundant molten Jie after the solvent among the container, contain the electrolyte that percetage by weight is 30-70% in polymeric dielectric, the mass ratio of above-mentioned first kind and second kind mixing is that 2:8 is to 3:5;

Above-mentioned first kind and second kind of polymeric material are mixed, add among the feed pot of copper work, control the rate of outflow of its above-mentioned mixed slurry by regulating pressure in the slurry, by adding the film that forms needed size with the slit of equipment, this film is at drying tunnel oven dry back harvest volume.