CN110265742A - Recycling prepares the method and system of composite positive pole from leftover bits and substandard products - Google Patents
Recycling prepares the method and system of composite positive pole from leftover bits and substandard products Download PDFInfo
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- CN110265742A CN110265742A CN201910547915.7A CN201910547915A CN110265742A CN 110265742 A CN110265742 A CN 110265742A CN 201910547915 A CN201910547915 A CN 201910547915A CN 110265742 A CN110265742 A CN 110265742A
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/54—Reclaiming serviceable parts of waste accumulators
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/84—Recycling of batteries or fuel cells
Abstract
Recycling that the invention discloses a kind of from leftover bits and substandard products prepares the method and system of composite positive pole.The described method includes: being classified to waste leftover waste material and substandard products, being crushed, positive plate is obtained；The binder in obtained positive plate is removed, then isolates positive plate through cold quenching, drying, screening, carries out calcination process later, obtains positive pole powder；To comprising the positive pole powder, lithium salts and the mixture progress ball milling and sintering processes that coat raw material, the composite positive pole of reparation is obtained.The present invention separates preferential removing positive pole powder and paillon with dry method, which is physical process, environmentally protective；Then then positive pole powder is modified into the anode composite powder after sintering is repaired by roasting removal carbon dust and organic matter again, can direct reuse in battery production.Method and process process of the invention is simple, and the rate of recovery is high, obtained good product consistency, and performance is stablized, and has very strong application potential.
Description
Technical field
The present invention relates to a kind of lithium battery anode recovery methods, and in particular to one kind recycles simultaneously from leftover bits and substandard products
The method and system for preparing composite positive pole belong to lithium battery recovery technology field.
Background technique
Lithium and lithium compound are important energy and material, are widely used in accumulation power supply and national defense construction.Lithium-ion electric
Pond has the characteristics that energy density is high, voltage platform is high, self discharge is small, memory-less effect, has developed into the master of 3C electronic product
The energy is wanted, the share of 80% or more consumer electronics market is occupied.Be benefited the industry high growth of new energy garage, domestic power battery 2017
Year realizes shipment 39.2GWh, it is contemplated that next three years CAGR is still expected to keep 30% or more.The useful life of passenger car battery is general
For 4-6, and electric commercial vehicle is since daily travel is long, the charging frequency is more, and effective battery life only about 3 years.Prediction 2020
Year power battery yield will be close to 40Gwh, it is contemplated that power battery yield will be close to 70Gwh, to contain metal values within 2022
Meter, market scale are expected to break through 10,000,000,000 yuan.
During producing lithium battery, the management level of each factory is different, and more or less there is defect wares, especially
It is a certain amount of positive plate leftover pieces.Leftover pieces in production process, although not passing through lithium ion with electrolyte contacts
Deintercalation, crystal structure do not change, but the powder cycle performance for passing through removing recycling has declined to a great extent, and decaying is serious.?
Positive electrode surface lithia easy to form or alkalization and stripping process destroy positive pole powder structure in stacking.How science
It is efficient to repair positive pole powder, direct reuse, it appears particularly important.
Current lithium battery recovery technology focuses primarily upon two hydrometallurgy, pyrometallurgy aspects.These methods are all real
Show and has recycled valuable metal element or synthesis presoma from waste lithium cell.Hydrometallurgical mainly uses alkali soluble Ore Leaching
Then valuable metal element is recycled using fractional precipitation or extraction.The alkali used mainly has sodium hydroxide, potassium hydroxide；Acid
It is divided into inorganic acid and organic acid, such as common inorganic acid hydrochloric acid, sulfuric acid, nitric acid even phosphoric acid, organic acid have citric acid, apple
Acid etc., organic extractant have P204, P507 etc., and the product of recycling is mostly sulfate or presoma.Pyrometallurgy mainly uses
High-temperature calcination removes organic matter and binder, then sieves, magnetic separation, removal of impurities again, obtains primary product.
Such as the powder of positive electrode is obtained using pretreatment in Chinese patent CN103199230A, it is then sour molten to clean
To nickeliferous manganese mixed solution, complexing agent is done using acetate, new to add nickel source or manganese source, then electrolytic cell Inner electrolysis makes nickel again
Manganese is deposited in titanium simultaneously, and the nickel manganese mixture of deposition is added lithium source in proportion and is sintered, nickel ion doped is obtained.The method
Thinking is fine, but does not purify out lithium salts, so that valuable lithium resource waste.It is used in Chinese patent CN10871048A
Alkali soluble solution aluminium foil, the then valuable metal element of Ore Leaching positive electrode, then pH value is adjusted after removing the impurity such as ferro-aluminum, it uses
P204 or P507 extraction manganese cobalt nickel obtains the products such as manganese sulfate, cobaltous sulfate, nickel sulfate, further high-temperature calcination preparation oxidation
The products such as cobalt, nickel oxide.Also without the recycling of clear lithium in the method, and the method for using organic solvent extraction, it is easy to make
It is also problem at the volatilization of organic matter and organic liquid waste processing.In addition it is forged in Chinese patent CN106785167A using high temperature
The method of burning recycles ternary nickel cobalt manganese material, and first high-temperature calcination 3-7min, then crushing, screening wait until positive electrode, then ball
Mill, water logging, separation of solid and liquid, obtain lithium-containing solution.The method technique is more environmentally friendly, but lithium recycling yield is relatively low, other metallic elements are simultaneously
Do not recycle well.
The recycling of the leftover pieces generated in battery core process of factory production is reported in the less report rarely having and is mainly collected
In in the Selectively leaching of iron phosphate lithium positive pole recycle lithium, or add lithium salts in proportion, phosphate radical, iron are sintered again.
Such as in Chinese patent CN106505273A, using alkali soluble and organic solvent removing by the way of obtain powder, then using
The modes such as roasting and calcining recycle iron phosphate lithium positive pole powder.
The recovery technology of waste lithium cell is more, and the recovery technology of early stage is only focused in the highest metal of certain economic values
The purification of element, method is relatively simple, and representative is exactly the cobalt recycled in waste and old cobalt acid lithium, does not have synthetical recovery lithium.
It and is currently pyrogenic process-Ore Leaching or alkali soluble-Ore Leaching to the most commonly used method of the recycling of old and useless battery valuable metal, then tie
It closes the modes such as precipitating, electrochemistry, extraction and recycles valuable metal element.Such as alkali soluble-Ore Leaching-extraction nickel cobalt preparation of manganese technology
In, although solvent extraction extraction efficiency is high, obtained product purity is high, organic solvent it is more or less there is molten damages
And volatile pollution environment, secondary pollution is caused, in addition extraction higher cost, there is limitations in the industrial production.For another example
Since nickel, cobalt equipotential are close, in electro-deposition techniques, nickel cobalt, which is returned, generates synchronous deposition, forms cobalt-nickel alloy, influences subsequent pure
Change, constrains the application of extension.Other methods such as ion-exchange, sulfide-oxidizing enzyme leaching etc. are all successfully by valuable metal member
Element recycling, but all there is certain limitations for these methods, if ion-exchange operation is more complicated, step is comparatively laborious,
It is only suitable for the separating-purifying of a small amount of ion；The culture of sulfide-oxidizing enzyme leaching-out technique bacterium, use condition are harsh, it is difficult to industrialization etc.
Factor all constrains the application of technology.Also, existing Retrieving Technology of Waste and Used Battery is essentially all precipitating or extraction
Then nickel cobalt manganese will purify lithium-containing solution, consume a large amount of soda acids and technique is tediously long, and product is the primary original for synthesizing positive electrode
Material.Furthermore the positive pole powder of conventional dry recycling contains a little metal impurities or removal process destroys original material because of it
Structure, the stability and consistency that the powder recycled is unable to direct reuse or warp simply modified material are bad, restrict
It recycles.
Summary of the invention
The main purpose of the present invention is to provide a kind of from leftover bits and substandard products, and recycling prepares composite positive pole
Method and system, to overcome deficiency in the prior art.
For achieving the above object, present invention employs following technical solutions:
The embodiment of the invention provides a kind of method that recycling prepares composite positive pole from leftover bits and substandard products,
Include:
Classified to waste leftover waste material and substandard products, be crushed, obtains positive plate；
The binder in obtained positive plate is removed, then isolates positive plate through cold quenching, drying, screening, is roasted later
Processing obtains positive pole powder；
To comprising the positive pole powder, lithium salts and the mixture progress ball milling and sintering processes that coat raw material, repaired
Composite positive pole.
In some embodiments, the method that the recycling from leftover bits and substandard products prepares composite positive pole is specifically wrapped
It includes:
(1) classified to waste leftover waste material and substandard products, be crushed, obtain positive plate；
(2) Low Temperature Heat Treatment is carried out to the positive plate, is at least used to remove the binder in the positive plate, then through cold
It quenches, dry, sieving and isolate positive plate, carrying out calcination process later, obtaining positive pole powder；
(3) positive pole powder, lithium salts and the cladding raw material Jing Guo calcination process are uniformly mixed, ball is carried out to obtained mixture
Mill, is sintered under protective atmosphere later, makes to coat raw material coating decoration on the surface of positive pole powder to be formed
Clad obtains the composite positive pole of reparation.
The embodiment of the invention also provides a kind of system that recycling prepares composite positive pole from leftover bits and substandard products,
Comprising:
Classification and crushing mechanism, can classify to waste leftover waste material and substandard products, be crushed；
Low Temperature Heat Treatment mechanism can remove the binder in positive plate；
Cold quenching-drying-screening mechanism can carry out cold quenching, drying and screening to the positive plate；
Mechanism is roasted, calcination process can be carried out to the positive plate screened out, obtain positive pole powder；
Ball milling mechanism can be such that the positive pole powder, lithium salts and cladding raw material uniformly mixes, obtain mixture；
It is sintered mechanism, the mixture can be sintered.
Compared with the prior art, the beneficial effects of the present invention are:
1) positive plate lift-off technology of the present invention is advanced, good separating effect.It is combined, is utilized with quenching using pyrolysis binder
It is shunk under different temperatures and ductility is inconsistent, remove positive electrode from positive plate, positive plate surface is smooth not oxidized,
It recycles and is free of metal fragment in positive pole powder；The technical process is simple, will not introduce organic matter or foreign ion；
2) recycling of the invention and the theory of reparation are new.Positive pole powder is screened and is combined with surface restoration technique by the present invention,
It in recycling positive pole powder surface layer coated inorganic material, avoids electrolyte and positive electrode is directly contacted, while being also positive material
Material supplement lithium source, and modification has been carried out to material, the powder of acquisition can be reused directly for lithium battery production, recycle and repair
Positive electrode afterwards has met or exceeded the cycle performance of completely new positive electrode, and capacity retention ratio and cycle performance are relatively completely new
Same type positive electrode is excellent；
3) recovery technique is new.Ball milling mixes burning after the present invention is added lithium salts and cladding raw material to the positive pole powder of recycling
Knot coats one layer of rich lithium layer, coating thickness 1-50nm on recycling powder surface.It is equal for being coated the positive electrode of modification
Even spherical shape, cycle performance is excellent, can be back to the production of lithium battery；
4) present invention is using Dry recovery as main means and the method that combines with surface modification recycles positive electrode simultaneously
Realize reparative regeneration, for whole set process process based on physical separation, recovery process is advanced, and whole process does not have mother liquor or acidification slag
Discharge, heat treatment process is mildly controllable, environmentally protective, prevent secondary environmental pollution, avoid traditional hydrometallurgy process,
Strict control pretreatment stage powder quality, direct mixing double sintering, and process equipment is advanced, easily operated, each process section
Parameter controllable precise, easy to operate, high degree of automation, and be easy to amplify, it is suitable for industrialized production.
Detailed description of the invention
Fig. 1 is that recycling prepares the side of composite positive pole from leftover bits and substandard products in a typical embodiments of the invention
The flow diagram of method.
Fig. 2 is the SEM figure that the positive electrode after cladding is obtained in an exemplary embodiments of the invention.
Fig. 3 is the XRD spectra for obtaining the positive electrode after cladding in an exemplary embodiments of the invention at a temperature of different disposal.
Fig. 4 is the 5C circulation figure of the positive electrode after coating in an exemplary embodiments of the invention.
Fig. 5 is the circulation figure of the positive electrode after coating in an exemplary embodiments of the invention.
Fig. 6 is the EDS spectrogram of powder before roasting in an exemplary embodiments of the invention.
Specific embodiment
In view of the disadvantage that existing waste leftover material recovery efficiency is low, technique is tediously long, inventor is through studying for a long period of time
With a large amount of practices, it is able to propose technical solution of the present invention, mainly includes leftover pieces classification, broken, Low Temperature Heat Treatment, roasting
The processing steps such as burning processing, ultrasonic Separation, screening, surface modification (addition lithium salts ball milling, high temperature sintering).Will not in the present invention
Powder acidification is leached, and is different from traditional handicraft and is leached positive pole powder, the elements such as nickel cobalt manganese and lithium are separately recovered, overcome original
Have that technique is tediously long, avoids secondary pollution.The powder assembled battery of recycling, big high rate performance is excellent, can direct reuse in lithium
Anode.This method has the characteristics that simple process, environmentally protective, valuable element direct reuse.
The technical solution, its implementation process and principle etc. will be further explained as follows.
As the one aspect of technical solution of the present invention, involved in be that one kind recycles system from leftover bits and substandard products
The method of standby composite positive pole comprising:
Classified to waste leftover waste material and substandard products, be crushed, obtains positive plate；
The binder in obtained positive plate is removed, then isolates positive plate through cold quenching, drying, screening, is roasted later
Processing obtains positive pole powder；
To comprising the positive pole powder, lithium salts and the mixture progress ball milling and sintering processes that coat raw material, repaired
Composite positive pole.
In some embodiments, the method that the recycling from leftover bits and substandard products prepares composite positive pole is specifically wrapped
It includes:
(1) classified to waste leftover waste material and substandard products, be crushed, obtain positive plate；
(2) Low Temperature Heat Treatment is carried out to the positive plate, is at least used to remove the binder in the positive plate, then through cold
It quenches, dry, sieving and isolate positive plate, carrying out calcination process later, obtaining positive pole powder；
(3) positive pole powder, lithium salts and the cladding raw material Jing Guo calcination process are uniformly mixed, ball is carried out to obtained mixture
Mill, is sintered under protective atmosphere later, makes to coat raw material coating decoration on the surface of positive pole powder to be formed
Clad obtains the composite positive pole of reparation.
In some embodiments, the waste leftover waste material derives from the discarded pole piece that lithium battery production process generates, example
Such as, waste and old ternary lithium battery leftover pieces, the lithium battery include nickel-cobalt-manganese ternary lithium battery, and main Types are with typical nickel ternary
Cobalt manganese powder body is anode, mainly there is 111,442,523,622,811,9055 etc. four kinds of typical types, but not limited to this.
Further, the waste leftover material type that the present invention is applicable in can be applicable to other than nickel-cobalt-manganese ternary material
The type cells positive electrode reparation such as LiFePO4, LiMn2O4, nickel cobalt aluminium ternary, can control according to the actual situation sintering atmosphere and
Coat different types of rich lithium material.
In some embodiments, in step (2), the temperature of the Low Temperature Heat Treatment is 350~650 DEG C, the time is 1~
360min。
In some embodiments, step (2) specifically includes: using quenching media make the temperature of the positive plate from 350~
650 DEG C of moments are reduced to 0~30 DEG C, are then dried in 30~100 DEG C, then sieved, finally in 500~850 DEG C into
0.1~10h of row calcination process.
Further, the quenching media includes ice water, cold water or cold wind etc..
Further, the aperture of the screening is 1.25~2000 μm.
Further, step (2) include: make the Low Temperature Heat Treatment and quenching alternately, also that is, During Quenching with
Pyrolysis processing process can convert repeatedly.
In some embodiments, in step (3), the process conditions of the sintering processes include: that sintering temperature is two sections, the
The sintering temperature in one stage is 450~650 DEG C, and the sintering temperature of second stage is 750~950 DEG C, sintering time is 0.5~
For 24 hours, heating rate is 1~20 DEG C of min, and sintering atmosphere includes compressed air, high purity oxygen gas atmosphere or inert gas atmosphere etc..
In some embodiments, the lithium salts includes any one in lithium hydroxide, lithium carbonate, lithium oxalate and lithium fluoride etc.
Kind or two or more combinations, but not limited to this.
In some embodiments, the cladding raw material includes in aluminium oxide, silica, titanium dioxide, yttrium oxide etc.
Any one or two or more combinations, but not limited to this.
Further, the molar ratio of the lithium salts and the positive pole powder Jing Guo calcination process is 1.01~1.10:1.
Further, the molar ratio of the cladding raw material and the positive pole powder Jing Guo calcination process is 1~10:100, also
That is, cladding amount of substance is positive the 1~10% of pole powder molal quantity.
Further, the clad with a thickness of 1~50nm.
Further, the material of the clad includes LiYO2、Li4SiO4、Li4TiO4Any one in or two
Kind or more combination, but not limited to this.
Wherein, shown in Figure 1 as more specifically one of case study on implementation of the invention, it is described from leftover bits and
The method that recycling prepares composite positive pole in substandard products may particularly include following steps:
The discarded pole piece generated using lithium battery production process is categorized, broken to obtain positive plate, Low Temperature Heat Treatment as raw material
Binder is removed, quenching-drying-screening obtains the positive pole powder and paillon of carbonaceous powder.Paillon, which directly recycles, is sold to downstream enterprise
Industry.Carbonaceous powder anode is using roasting removal organic matter and carbon dust, then adds the lithium salts of certain mol proportion example, cladding raw material together
Positive electrode, the composite positive pole after the reparation of acquisition are re-sintered after mixing ball milling.
Further, the present invention directly obtains primary powder using Dry recovery.It is pyrolyzed using controllable heat treatment process
Binder, gradation sizing obtain primary material and isolate paillon, do not introduce new impurity.
Rerolling sintering synthesis composite positive pole of the present invention.After powder and surface modification material mixing that screening is obtained
Solid-phase sintering is made the best use of everything, and so that micro metal oxide is coated on the surface of positive electrode, electrolyte is avoided directly to contact,
Improve and improve the cyclical stability of positive electrode.
As the one aspect of technical solution of the present invention, involved in be that one kind recycles system from leftover bits and substandard products
The system of standby composite positive pole comprising:
Classification and crushing mechanism, can classify to waste leftover waste material and substandard products, be crushed；
Low Temperature Heat Treatment mechanism can remove the binder in positive plate；
Cold quenching-drying-screening mechanism can carry out cold quenching, drying and screening to the positive plate；
Mechanism is roasted, calcination process can be carried out to the positive plate screened out, obtain positive pole powder；
Ball milling mechanism can be such that the positive pole powder, lithium salts and cladding raw material uniformly mixes, obtain mixture；
It is sintered mechanism, the mixture can be sintered.
Further, the system can specifically mainly include cutting machine, standard screen, pyrolysis kiln, Muffle furnace, tubular type
Furnace, ball mill, pneumatic separator, drying box, eddy current separator, reaction kettle etc., but not limited to this.
In conclusion the present invention separates preferential removing positive pole powder and paillon with dry method, which is physical process,
It is environmentally protective；Then then positive pole powder is modified into answering after sintering is repaired by roasting removal carbon dust and organic matter again
Close positive pole powder, can direct reuse in battery production.Method and process process of the invention is simple, and the rate of recovery is high, obtained product
Consistency is good, and performance is stablized, and has very strong application potential.
Below with reference to several preferred embodiments and attached drawing, further details of the technical solution of the present invention, it is clear that
Described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.Based on the implementation in the present invention
Example, those of ordinary skill in the art's every other embodiment obtained without making creative work, all belongs to
In the scope of protection of the invention.The test method of actual conditions is not specified in the following example, usually according to normal condition.
Embodiment 1
Using some type of waste and old ternary lithium battery leftover pieces as raw material.Waste leftover material is cut into 0.5x0.5cm first
Clast 2kg take out while hot into after being heat-treated 10min at 650 DEG C of temperature in pyrolysis kiln and be added directly into ice water and quench
It is cold, 30 DEG C are reduced to from 650 DEG C of moments, while ultrasonic vibration handles 20min, remove positive electrode and aluminium foil, use griddle
Divide filtering aluminium foil and black powder, obtains the smooth aluminium foil in surface.Black powder is filtered out into moisture secondary sieve after 50 DEG C of drying
Point, filter out metal fragment；Obtain carbon containing positive pole powder.Carbon containing powder is roasted in air atmosphere, temperature is 850 DEG C, the time
For 0.5h.Sampling weighs, respectively the lithium salts of excessive addition 5% and 8% and titanium dioxide, and ball milling mixes, lithium salts and by roasting
The molar ratio of the positive pole powder of reason is 1.01:1, and the molar ratio of titanium dioxide and positive pole powder Jing Guo calcination process is 1:100.
Material after mixing is sintered in tube furnace, 5 DEG C/min of heating rate, until being continuously heating to 850 after constant temperature 4h at 470 DEG C
DEG C, natural cooling after constant temperature 8h.Sintering atmosphere is the sintering of high purity oxygen gas atmosphere.By the material assembled battery after coating modification, test
Chemical property, the positive pole powder 5C circulation initial capacity after titanium coating modification reach 115mAh/g, the capacity after 125 circles
Conservation rate reaches 90% or more.
The process flow is short, environmentally protective, and metal foil has been separately recovered and the positive pole powder rate of recovery is high, and has repaired with surface
Decorations technology combines the positive electrode being had excellent performance.This method is easy to operate, be easy to be mass produced, and recycles and repairs
Positive electrode can direct reuse in the production of lithium battery.
Embodiment 2
Using some type of waste and old ternary lithium battery leftover pieces as raw material.Waste leftover material is cut into 0.2x0.2cm first
Clast 1.2kg, into pyrolysis oven at 400 DEG C of temperature be heat-treated 6h after, while hot take out be added directly into quenching in ice water,
20 DEG C are reduced to from 550 DEG C of moments, while ultrasonic vibration handles 15min, remove positive electrode and aluminium foil, be sieving through with macropore
Aluminium foil and black powder are filtered, the smooth aluminium foil in surface is obtained.Black powder is filtered out into moisture regrading after 80 DEG C of drying, filter
Except metal fragment；Obtain carbon containing positive pole powder.Carbon containing powder is roasted in air atmosphere, temperature is 700 DEG C, time 10h.
Sampling weighs, the lithium salts and silica of excessive addition 8%, and ball milling mixes, lithium salts and the positive pole powder Jing Guo calcination process
Molar ratio is 1.03:1, and the molar ratio of silica and the positive pole powder Jing Guo calcination process is 3:100.By the material after mixing
It is sintered in tube furnace, 5 DEG C/min of heating rate, until it is continuously heating to 950 DEG C at 450 DEG C after constant temperature 4h, it is natural after constant temperature 8h
It is cooling.Sintering process is passed through compressed air sintering.By the material assembled battery after coating modification, chemical property is tested, through titanium
Positive pole powder 5C circulation initial capacity after coating modification reaches 109mAh/g, and capacity retention ratio reaches 95% after 100 circles.
The process flow is short, environmentally protective, and metal foil has been separately recovered and the positive pole powder rate of recovery is high, and has repaired with surface
Decorations technology combines the positive electrode being had excellent performance.This method is easy to operate, be easy to be mass produced, and recycles and repairs
Positive electrode can direct reuse in the production of lithium battery.
Embodiment 3
Using some type of waste and old ternary lithium battery leftover pieces as raw material.Waste leftover material is cut into 0.5x0.5cm first
Clast 2.5kg take out while hot into after being heat-treated 1min at 650 DEG C of temperature in pyrolysis oven and be added directly into ice water and quench
It is cold, 10 DEG C are reduced to from 450 DEG C of moments, while ultrasonic vibration handles 20min, remove positive electrode and aluminium foil, use griddle
Divide filtering aluminium foil and black powder, obtains the smooth aluminium foil in surface.Black powder is filtered out into moisture secondary sieve after 60 DEG C of drying
Point, filter out metal fragment；Obtain carbon containing positive pole powder.Carbon containing powder is roasted in oxygen-enriched atmosphere, temperature is 750 DEG C, the time
For 2h.Sampling weighs, the lithium salts and yttrium oxide of excessive addition 3%, and ball milling mixes, lithium salts and the positive pole powder Jing Guo calcination process
Molar ratio be 1.05:1, the molar ratio of yttrium oxide and positive pole powder Jing Guo calcination process is 5:100.By the material after mixing
It is sintered in tube furnace, 1 DEG C/min of heating rate, until being continuously heating to 750 DEG C at 650 DEG C after constant temperature 6h, constant temperature is natural after for 24 hours
It is cooling.Sintering atmosphere is oxygen-enriched sintering.By the material assembled battery after coating modification, chemical property is tested, is changed through titanium cladding
Property after positive pole powder 5C circulation initial capacity reach 125mAh/g, by 100 circle after capacity retention ratio reach 94%.
The process flow is short, environmentally protective, and metal foil has been separately recovered and the positive pole powder rate of recovery is high, and has repaired with surface
Decorations technology combines the positive electrode being had excellent performance.This method is easy to operate, be easy to be mass produced, and recycles and repairs
Positive electrode can direct reuse in the production of lithium battery.
Embodiment 4
Using some type of waste and old ternary lithium battery leftover pieces as raw material.Waste leftover material is cut into 0.5x0.5cm first
Clast 2.2kg, into pyrolysis oven at 500 DEG C of temperature be heat-treated 1h after, while hot take out be added directly into quenching in ice water,
It is reduced to 0 DEG C from 350 DEG C of moments, while ultrasonic vibration handles 20min, removes positive electrode and aluminium foil, be sieving through with macropore
Aluminium foil and black powder are filtered, the smooth aluminium foil in surface is obtained.Black powder is filtered out into moisture regrading after 50 DEG C of drying, filter
Except metal fragment；Obtain carbon containing positive pole powder.Carbon containing powder is roasted in oxygen-enriched atmosphere, temperature is 500 DEG C, time 1h.
Sampling weighs, the lithium salts and tin oxide of excessive addition 5%, and ball milling mixes, and lithium salts rubs with the positive pole powder Jing Guo calcination process
You are 8:100 than the molar ratio of the positive pole powder for 1.08:1, tin oxide and Jing Guo calcination process.By the material after mixing in pipe
It is sintered in formula furnace, 10 DEG C/min of heating rate, until it is continuously heating to 820 DEG C at 480 DEG C after constant temperature 6h, it is naturally cold after constant temperature 10h
But.Sintering atmosphere is oxygen-enriched sintering.By the material assembled battery after coating modification, chemical property is tested, through titanium coating modification
Positive pole powder 5C circulation initial capacity afterwards reaches 128mAh/g, and capacity retention ratio reaches 93% after 100 circles.
The process flow is short, environmentally protective, and metal foil has been separately recovered and the positive pole powder rate of recovery is high, and has repaired with surface
Decorations technology combines the positive electrode being had excellent performance.This method is easy to operate, be easy to be mass produced, and recycles and repairs
Positive electrode can direct reuse in the production of lithium battery.
Embodiment 5
Using some type of waste and old ternary lithium battery leftover pieces as raw material.Waste leftover material is cut into 0.8x0.8cm first
Clast 1.5kg, into pyrolysis oven at 350 DEG C of temperature be heat-treated 6h after, while hot take out be added directly into quenching in ice water,
30 DEG C are reduced to from 500 DEG C of moments, while ultrasonic vibration handles 30min, remove positive electrode and aluminium foil, be sieving through with macropore
Aluminium foil and black powder are filtered, the smooth aluminium foil in surface is obtained.Black powder is filtered out into moisture regrading after 100 DEG C of drying,
Filter out metal fragment；Obtain carbon containing positive pole powder.Carbon containing powder is roasted in pure oxygen atmosphere, temperature is 850 DEG C, and the time is
0.1h.Sampling weighs, the lithium salts and yttrium oxide of excessive addition 3%, and ball milling mixes, lithium salts and the positive pole powder Jing Guo calcination process
Molar ratio be 1.10:1, the molar ratio of yttrium oxide and positive pole powder Jing Guo calcination process is 10:100.By the object after mixing
Material is sintered in tube furnace, 20 DEG C/min of heating rate, until 900 DEG C are continuously heating to after constant temperature 0.5h at 650 DEG C, constant temperature 10h
Natural cooling afterwards.Sintering atmosphere is oxygen-enriched sintering.By the material assembled battery after coating modification, chemical property is tested, through titanium
Positive pole powder 5C circulation initial capacity after coating modification reaches 118mAh/g, and capacity retention ratio reaches 92% after 100 circles.
The process flow is short, environmentally protective, and metal foil has been separately recovered and the positive pole powder rate of recovery is high, and has repaired with surface
Decorations technology combines the positive electrode being had excellent performance.This method is easy to operate, be easy to be mass produced, and recycles and repairs
Positive electrode can direct reuse in the production of lithium battery.
The SEM figure that the positive electrode after cladding is obtained in an exemplary embodiments of the invention please refers to shown in Fig. 2, different disposal
At a temperature of obtain the XRD spectra of positive electrode after cladding and please refer to shown in Fig. 3, the 5C circulation of the positive electrode after cladding
Figure please refers to shown in Fig. 4, and the circulation figure that the positive electrode after cladding is obtained in an exemplary embodiments of the invention please refers to Fig. 5
It is shown.The EDS spectrogram of powder please refers to shown in Fig. 6 before roasting in an exemplary embodiments of the invention.
In conclusion by above-mentioned technical proposal of the invention, the present invention with dry method separate preferential removing positive pole powder and
Paillon, which is physical process, environmentally protective；Then by positive pole powder by roasting removal carbon dust and organic matter, so
Modify again afterwards sintering repaired after anode composite powder, can direct reuse in battery production.Method and process stream of the invention
Journey is simple, and the rate of recovery is high, obtained good product consistency, and performance is stablized, and has very strong application potential.
Each aspect of the present invention, embodiment, feature and example should be regarded as to be illustrative and is not intended to limit in all respects
The system present invention, the scope of the present invention are only defined by tbe claims.Without departing substantially from the spirit and scope of the present invention advocated
In the case of, it will be apparent to those skilled in the art that other embodiments, modification and use.
The use of title and chapters and sections is not intended to limit the present invention in case of the present invention；Each chapters and sections can be applied to the present invention
Any aspect, embodiment or feature.
Case of the present invention in the whole text in, composition is being described as have, containing or comprising in place of specific component or will
Process description is in place of having, containing or comprising particular procedure step, it is contemplated that the composition of teachings of this disclosure is also substantially by institute
Narration component composition is made of described component, and the process of teachings of this disclosure is also substantially made of described process steps
Or it is made of described process steps group.
Unless otherwise specific statement, otherwise term " include (include, includes, including) ", " have
The use of (have, has or having) " is it is generally understood that be open and without limitation.
It should be understood that the order of each step or the order of execution specific action are not particularly significant, as long as teachings of this disclosure is protected
Holding can operate.In addition, two or more steps or movement can be carried out simultaneously.
In addition, inventor also refers to previous embodiment, other raw materials for being addressed with this specification, technological operation, work
Skill condition is tested, and obtains ideal result.
Although describing the present invention with reference to an illustrative embodiment, those skilled in the art will appreciate that, it is not carrying on the back
Various other changes can be made in the case where from spirit and scope of the present invention, are omitted and/or are added and can use substantial equivalents
Substitute the element of the embodiment.In addition, many modifications can be made without departing substantially from the scope of the present invention so that specific
Situation or material adapt to teachings of the present invention.Therefore, it is not to restrict the invention to herein for executing institute of the invention
Specific embodiment is disclosed, and being intended to makes the present invention by all implementations comprising falling within the scope of the appended claims
Example.In addition, removing non-specific statement, otherwise any use of term first, second etc. does not indicate any order or importance, but
An element and another element are distinguished using term first, second etc..
Claims (10)
1. a kind of method that recycling prepares composite positive pole from leftover bits and substandard products, characterized by comprising:
Classified to waste leftover waste material and substandard products, be crushed, obtains positive plate；
The binder in obtained positive plate is removed, then isolates positive plate through cold quenching, drying, screening, carries out calcination process later,
Obtain positive pole powder；
To comprising the positive pole powder, lithium salts and the mixture progress ball milling and sintering processes that coat raw material, answering for reparation is obtained
Close positive electrode.
2. the method according to claim 1 that recycling prepares composite positive pole from leftover bits and substandard products, feature
It is to specifically include:
(1) classified to waste leftover waste material and substandard products, be crushed, obtain positive plate；
(2) Low Temperature Heat Treatment is carried out to the positive plate, at least for removing binder in the positive plate, then through cold quenching,
Positive plate is isolated in drying, carries out calcination process later, obtains positive pole powder；
(3) positive pole powder, lithium salts and the cladding raw material Jing Guo calcination process are uniformly mixed, ball milling are carried out to obtained mixture,
It is sintered under protective atmosphere later, makes to coat raw material coating decoration on the surface of positive pole powder to form cladding
Layer, obtains the composite positive pole of reparation.
3. the method according to claim 1 or 2 that recycling prepares composite positive pole from leftover bits and substandard products, special
Sign is: the waste leftover waste material derives from the discarded pole piece that lithium battery production process generates, and the lithium battery includes nickel cobalt
Manganese ternary lithium battery, ferric phosphate lithium cell, lithium manganate battery or nickel cobalt aluminium ternary lithium battery；Preferably, the nickel-cobalt-manganese ternary
The type of lithium battery includes 111,442,523,622,811 or 9055 types.
4. the method according to claim 2 that recycling prepares composite positive pole from leftover bits and substandard products, feature
Be: in step (2), the temperature of the Low Temperature Heat Treatment is 350~650 DEG C, and the time is 1~360min.
5. the method according to claim 2 that recycling prepares composite positive pole from leftover bits and substandard products, feature
Be, step (2) specifically includes: using quenching media make the temperature of the positive plate be reduced to 0 from 350~650 DEG C of moments~
It 30 DEG C, is then dried in 30~100 DEG C, then sieved, finally in 500~850 DEG C of 0.1~10h of progress calcination process；
Preferably, the quenching media includes ice water, cold water or cold wind；Preferably, the aperture of the screening is 1.25~2000 μm；It is excellent
Choosing, step (2) includes: to make the Low Temperature Heat Treatment and quenching alternately.
6. the method according to claim 2 that recycling prepares composite positive pole from leftover bits and substandard products, feature
It is, in step (3), the process conditions of the sintering processes include: that sintering temperature is two sections, and the sintering temperature of first stage is
450~650 DEG C, the sintering temperature of second stage is 750~950 DEG C, sintering time is 0.5~for 24 hours, heating rate is 1~20
DEG C min, sintering atmosphere includes oxygen-enriched atmosphere or inert gas atmosphere.
7. the method according to claim 2 that recycling prepares composite positive pole from leftover bits and substandard products, feature
Be: the lithium salts includes any one or two or more groups in lithium hydroxide, lithium carbonate, lithium oxalate and lithium fluoride
It closes；
And/or the cladding raw material includes aluminium oxide, silica, titanium dioxide, any one or two kinds in yttrium oxide
Above combination.
8. the method according to claim 2 that recycling prepares composite positive pole from leftover bits and substandard products, feature
Be: the molar ratio of the lithium salts and the positive pole powder Jing Guo calcination process is 1.01~1.10:1；
And/or the raw material and the molar ratio of the positive pole powder Jing Guo calcination process of coating is 1~10:100.
9. the method according to claim 2 that recycling prepares composite positive pole from leftover bits and substandard products, feature
Be: the clad with a thickness of 1~50nm；
And/or the material of the clad includes LiYO2、Li4SiO4、Li4TiO4In any one or two or more groups
It closes.
10. a kind of system that recycling prepares composite positive pole from leftover bits and substandard products, characterized by comprising:
Classification and crushing mechanism, can classify to waste leftover waste material and substandard products, be crushed；
Low Temperature Heat Treatment mechanism can remove the binder in positive plate；
Cold quenching-drying-screening mechanism can carry out cold quenching, drying and screening to the positive plate；
Mechanism is roasted, calcination process can be carried out to the positive plate screened out, obtain positive pole powder；
Ball milling mechanism can be such that the positive pole powder, lithium salts and cladding raw material uniformly mixes, obtain mixture；
It is sintered mechanism, the mixture can be sintered.
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