阅读说明：本技术 一种锂离子电池前躯体粒径分布可控的制备方法 (Preparation method capable of controlling particle size distribution of lithium ion battery precursors ) 是由 王明彩 程迪 尹正中 徐云军 王艳平 梁国文 李国华 曹秉伟 于 2018-07-20 设计创作，主要内容包括：本发明涉及一种锂离子电池前躯体粒径分布可控的制备方法,化学式为Ni<Sub>x</Sub>Co<Sub>y</Sub>Mn<Sub>1-x-y</Sub>(OH)<Sub>2</Sub>或Ni<Sub>x</Sub>Co<Sub>y</Sub>Al<Sub>1-x-y</Sub>(OH)<Sub>2</Sub>,0.2<x<0.99,0<y<0.8,包括步骤：将镍盐、钴盐、锰盐或铝盐配制溶液；碱溶液；络合剂溶液；反应得出粒径分布窄的前驱体；用计量泵将上述步骤A、步骤B、步骤C的溶液,同时加入反应釜1中,控制流量、温度、反应pH,通入保护气体,搅拌速度,反应后,等粒径达到目标要求后,结束,停止反应；将固液分离,最后进行干燥处理,即制备得锂离子电池前驱体。本发明提高了材料的压实密度和极片涂布的一致性,增加电芯循环寿命,降低电池的极化而改善倍率性能。(The invention relates to a preparation method with controllable particle size distribution of lithium ion battery precursors, wherein the chemical formula is Ni x Co y Mn 1‑x‑y (OH) 2 Or Ni x Co y Al 1‑x‑y (OH) 2 ，0.2<x<0.99，0<y<0.8, comprising the steps of: preparing a solution from nickel salt, cobalt salt, manganese salt or aluminum salt; an alkali solution; a complexing agent solution; reacting to obtain a precursor with narrow particle size distribution; adding the solutions obtained in the steps A, B and C into the reaction kettle 1 by using a metering pump, controlling the flow, the temperature and the reaction pH, and introducing into a reactorThe method comprises the steps of protecting gas, stirring, reacting, stopping the reaction after the particle size reaches the target requirement, separating solid from liquid, and finally drying to obtain the lithium ion battery precursor.)

1, preparation method with controllable particle size distribution of lithium ion battery precursor, whose chemical formula is Ni_xCo_yMn_1-x-y(OH)₂Or Ni_xCo_yAl_1-x-y(OH)_2.The method is characterized in that: 0.2<x<0.99，0<y<0.8, comprising the following process steps:

A. preparing a solution from nickel salt, cobalt salt, manganese salt or aluminum salt, wherein the concentration of the solution is 0.5-3 mol/L, and the elements in the solution can be any of nickel cobalt, nickel manganese, nickel cobalt manganese and nickel cobalt aluminum;

B. preparing an alkali solution with the concentration of 1.5-10 mol/L;

C. preparing a complexing agent solution with the concentration of 2-15 mol/L;

D. two reaction kettles 1 and 2 which can be connected in series are used for reaction to obtain a precursor with narrow particle size distribution;

E. adding the solutions obtained in the steps A, B and C into a reaction kettle 1 by using a metering pump or a constant flow pump, controlling the flow, the temperature and the reaction pH, introducing protective gas, stirring at a speed, reacting for 0.1-500h, then putting the mother liquor 1/2 of the reaction kettle 1 into a reaction kettle 2, and then, respectively reacting the two kettles, controlling the flow, the temperature and the reaction pH, introducing the protective gas, stirring at a speed, and stopping the reaction when the particle size reaches the target requirement of 2.0-25.0 um;

F. and after the reaction is finished, carrying out solid-liquid separation, washing the anode material precursor obtained by the solid-liquid separation with deionized water, and finally carrying out drying treatment to obtain the lithium ion battery precursor.

2. The method for preparing lithium ion battery precursors with controllable particle size distribution according to claim 1, wherein the obtained precursor is spherical nickel cobalt manganese hydroxide or spherical nickel cobalt aluminum hydroxide.

3. The preparation method with controllable particle size distribution of lithium ion battery precursors according to claim 1, wherein in step A, the nickel salt is any or any combination of more than two of nickel sulfate, nickel chloride, nickel carbonate, nickel acetate or nickel nitrate, preferably nickel sulfate, the cobalt salt is any or any combination of more than two of cobalt sulfate, cobalt chloride, cobalt carbonate, cobalt acetate or cobalt nitrate, preferably cobalt sulfate, the manganese salt is any or any combination of more than two of manganese sulfate, manganese chloride, manganese acetate, manganese carbonate or manganese nitrate, preferably manganese sulfate, the aluminum salt is any or any combination of more than two of aluminum chloride, aluminum sulfate, aluminum acetate, aluminum nitrate, aluminum carbonate or sodium metaaluminate, preferably sodium metaaluminate;

in the step B, the alkali solution is any or the composition of any two or more of sodium hydroxide, potassium hydroxide and lithium hydroxide;

in the step C, the complexing agent is any or a composition of any two or more of ammonia water, ammonium bicarbonate, citric acid, ammonium carbonate, ethylenediamine and disodium ethylene diamine tetraacetate.

4. The preparation method with controllable particle size distribution of lithium ion battery precursors according to claim 3, wherein the ratio of nickel salt is 0.1-0.9:0.1-0.9 when the nickel salt is a combination of any two of nickel sulfate, nickel chloride, nickel carbonate, nickel acetate or nickel nitrate, the ratio of cobalt salt is 0.1-0.9:0.1-0.9 when the cobalt salt is a combination of any two of cobalt sulfate, cobalt chloride, cobalt carbonate, cobalt acetate or cobalt nitrate, the ratio of manganese salt is 0.1-0.9:0.1-0.9 when the manganese salt is a combination of any two of manganese sulfate, manganese chloride, manganese acetate, manganese carbonate or manganese nitrate, the ratio of the aluminum salt is 0.1-0.9:0.1-0.9, the ratio of the aluminum salt is a combination of any two of aluminum chloride, aluminum sulfate, aluminum acetate, aluminum nitrate, aluminum carbonate or sodium metaaluminate, the ratio of the alkali solution is 0.1-0.9:0.1-0.9, and the ratio of ethylene diamine tetra-0.9: 0.9.

5. The preparation method with controllable particle size distribution of lithium ion battery precursors according to claim 3, wherein the nickel salt is preferably nickel sulfate, the manganese salt is preferably manganese sulfate, and the aluminum salt is preferably sodium metaaluminate.

6. The method for preparing lithium ion battery precursors with controllable particle size distribution according to claim 1, wherein in step D, the reactors 1 and 2 can be used in series or separately, and the reactors have the same volume, which is between 0.001-30m 3.

7. The preparation methods of controllable particle size distribution of lithium ion battery precursors of claim 1, wherein in step D, the solution is reacted in reactor 1, after 1-50h, 1/2 from bottom valve to reactor 2, reactor 1 and reactor 2 are reacted simultaneously by the same or different process, respectively, until the particle size reaches the target value of 2.0-25.0um, the reaction is stopped, and batch production can be achieved, and precursor with narrow particle size distribution can be obtained.

8. The preparation method of controllable particle size distribution of lithium ion battery precursors according to claim 1, wherein in step D, the preparation method comprises a reaction vessel 1 and a reaction vessel 2, overflow pipelines are arranged between the reaction vessel 1 and the reaction vessel 2, the management intersection of the reaction vessel 2 is higher than the reaction vessel 1, the solution reacts in the reaction vessel 1, after hours, when the solution approaches the reaction vessel mouth, a lower overflow valve is opened and flows into the reaction vessel 2 along the pipeline, the reaction vessel 2 is in a static environment, when the solution overflows to the upper mouth of the reaction vessel 2, the upper solution of the reaction vessel 2 passes through a static environment, the upper solution is a clear solution, the clear solution is pumped out by a pump, the pumped out flow rate is equal to the sum of the solution flow rates entering the reaction vessel 1, meanwhile, the liquids of the reaction vessel 1 and the reaction vessel 2 can mutually circulate through the pipeline, so that the particle sizes of the reaction vessel 1 and the reaction vessel 2 are , the clear solution of the reaction vessel 2 is continuously pumped out by a pump, the solid content is increased from 0%, the final particle size distribution is increased, and the particle size distribution of the precursor can be increased to 0.25, and the batch production can be achieved.

9. The preparation methods with controllable particle size distribution of lithium ion battery precursors according to claim 1, wherein in step E, the solution flow is 0.01-2000L/h, the stirring speed is 100-1000 r/min, the temperature is 30-80 ℃, the pH is 9-13.5, the protective gas is nitrogen, the flow is 0.01-80m³/h。

10. The method for preparing lithium ion battery precursors with controllable particle size distribution according to claim 7, wherein the same or different processes comprise a solution flow rate of 0.01-2000L/h and a stirring speed of 0.01-2000L/h100-1000 r/min, 30-80 ℃, pH 9-13.5, and nitrogen as protective gas with flow rate of 0.01-80m³/h。

Technical Field

The invention belongs to the technical field of new energy material preparation, and particularly relates to a preparation method of lithium ion battery anode material gradient precursors.

Background

The lithium ion battery, as a new generation environment-friendly and high-energy battery, has become which is the key point of the development of the battery industry, has the advantages of high working voltage, small volume, light weight, no memory effect, high specific energy, little environmental pollution, low self-discharge rate, rapid charge and discharge of some systems, wide working temperature range, long cycle life, good safety performance and the like, not only has a broad application prospect in the automobile industry, but also in various aspects of electronic equipment, national defense industry, the aerospace field, military science and technology and the like,

at present, precursor preparation methods with narrower particle size distribution become the focus of attention, and the invention solves the difficult problems, such as wide particle size distribution inevitably causes different Li contents in large particles and small particles, wherein the Li and nickel contents in the small particles are higher than the average value (Li and nickel are excessive) and the Li and nickel contents in the large particles are lower than the average value (Li and nickel are insufficient), so that in the charging process, due to polarization, the small particles always excessively remove Li, the structure is damaged, the side reaction with electrolyte is severe, the high temperature is more obviously reduced, the cycle life of the material is rapidly reduced, and the performance is influenced.

In order to improve the current situation of , a precursor with uniform particle size (small particle size distribution) must be produced, which has the advantages of obviously improving sensitivity of pole piece coating, increasing the cycle life of a battery cell, reducing polarization of the battery and improving rate performance, and the precursor with narrow particle size distribution can become important technical indexes of power materials.

For the hydroxide precipitation process, it is impossible to produce a precursor with a narrow particle size distribution using a common reaction.

Disclosure of Invention

The invention aims to provide preparation methods with controllable particle size distribution of precursors of lithium ion batteries, which solve the defect of uneven particle size distribution, improve the compaction density of materials and the sensitivity of pole piece coating, increase the cycle life of a battery core, and reduce the polarization of the battery to improve the rate capability.

In order to achieve the purpose, the invention has the following technical scheme:

the preparation method with controllable particle size distribution of lithium ion battery precursors has a chemical formula of Ni_xCo_yMn_1-x-y(OH)₂Or Ni_xCo_yAl_1-x-y(OH)_2.，0.2<x<0.99，0<y<0.8, comprising the following process steps:

A. preparing a solution from nickel salt, cobalt salt, manganese salt or aluminum salt, wherein the concentration of the solution is 0.5-3 mol/L, and the elements in the solution can be any of nickel cobalt, nickel manganese, nickel cobalt manganese and nickel cobalt aluminum;

B. preparing an alkali solution with the concentration of 1.5-10 mol/L;

C. preparing a complexing agent solution with the concentration of 2-15 mol/L;

D. two reaction kettles 1 and 2 which can be connected in series are used for reaction to obtain a precursor with narrow particle size distribution;

E. adding the solutions obtained in the steps A, B and C into a reaction kettle 1 by using a metering pump or a constant flow pump, controlling the flow, the temperature and the reaction pH, introducing protective gas, stirring at a speed, reacting for 0.1-500h, then putting the mother liquor 1/2 of the reaction kettle 1 into a reaction kettle 2, and then, respectively reacting the two kettles, controlling the flow, the temperature and the reaction pH, introducing the protective gas, stirring at a speed, and stopping the reaction when the particle size reaches the target requirement of 2.0-25.0 um;

F. and after the reaction is finished, carrying out solid-liquid separation, washing the anode material precursor obtained by the solid-liquid separation with deionized water, and finally carrying out drying treatment to obtain the lithium ion battery precursor.

Wherein the obtained precursor is spherical nickel cobalt manganese hydroxide or spherical nickel cobalt aluminum hydroxide.

In the step A, nickel salt is or the composition of any two or more of nickel sulfate, nickel chloride, nickel carbonate, nickel acetate or nickel nitrate, wherein nickel sulfate is preferred, cobalt salt is or the composition of any two or more of cobalt sulfate, cobalt chloride, cobalt carbonate, cobalt acetate or cobalt nitrate, wherein cobalt sulfate is preferred, manganese salt is or the composition of any two or more of manganese sulfate, manganese chloride, manganese acetate, manganese carbonate or manganese nitrate, wherein manganese sulfate is preferred, aluminum salt is or the composition of any two or more of aluminum chloride, aluminum sulfate, aluminum acetate, aluminum nitrate, aluminum carbonate or sodium metaaluminate, wherein sodium metaaluminate is preferred;

in the step B, the alkali solution is any or the composition of any two or more of sodium hydroxide, potassium hydroxide and lithium hydroxide;

in the step C, the complexing agent is any or a composition of any two or more of ammonia water, ammonium bicarbonate, citric acid, ammonium carbonate, ethylenediamine and disodium ethylene diamine tetraacetate.

Wherein when the nickel salt is a composition of any two of nickel sulfate, nickel chloride, nickel carbonate, nickel acetate or nickel nitrate, the proportion is 0.1-0.9: 0.1-0.9; when the cobalt salt is any two of cobalt sulfate, cobalt chloride, cobalt carbonate, cobalt acetate or cobalt nitrate, the proportion is 0.1-0.9: 0.1-0.9; when the manganese salt is a composition of any two of manganese sulfate, manganese chloride, manganese acetate, manganese carbonate or manganese nitrate, the proportion of the manganese salt is 0.1-0.9: 0.1-0.9; when the aluminum salt is any two of aluminum chloride, aluminum sulfate, aluminum acetate, aluminum nitrate, aluminum carbonate or sodium metaaluminate, the proportion is 0.1-0.9: 0.1-0.9; when the alkali solution is any two of sodium hydroxide, potassium hydroxide and lithium hydroxide, the ratio of the alkali solution to the lithium hydroxide is 0.1-0.9: 0.1-0.9; when the complexing agent is any two of ammonia water, ammonium bicarbonate, citric acid, ammonium carbonate, ethylenediamine and disodium ethylene diamine tetraacetate, the proportion is 0.1-0.9: 0.1-0.9;

wherein, the nickel salt is preferably nickel sulfate; the nickel salt is preferably nickel sulfate; the manganese salt is preferably manganese sulfate; the aluminium salt is preferably sodium metaaluminate.

In the step D, the reaction kettles 1 and 2 can be used in series or independently, the volumes of the reaction kettles are the same, and the volume of the reaction kettles is 0.001-30m 3;

and D, reacting the solution in the reaction kettle 1 for 1-50 hours, putting 1/2 into the reaction kettle 2 from a bottom valve, reacting the reaction kettle 1 and the reaction kettle 2 simultaneously by the same or different processes respectively, and stopping the reaction until the particle size reaches a target value of 2.0-25.0 microns, so that batch production can be realized, and a precursor with narrow particle size distribution can be obtained.

Step D, the method comprises a reaction kettle 1 and a reaction kettle 2, overflow pipelines are arranged between the reaction kettle 1 and the reaction kettle 2, a management intersection of the reaction kettle 2 is higher than the reaction kettle 1, a solution reacts in the reaction kettle 1, after hours, when the solution approaches a reaction kettle opening, a lower overflow opening valve is opened, the solution flows into the reaction kettle 2 along a pipeline, the reaction kettle 2 is in a static environment, when the solution overflows to an upper opening of the reaction kettle 2, the upper solution of the reaction kettle 2 passes through a static environment, the upper solution is clear liquid, the upper clear liquid is pumped out by a pump, the pumped flow is equal to the sum of the solution flow entering the reaction kettle 1, meanwhile, the liquids of the reaction kettle 1 and the reaction kettle 2 can flow through the pipelines, so that the particle size of the reaction kettle 1 and the reaction kettle 2 is consistent, the upper clear liquid of the reaction kettle 2 is continuously pumped out by the pump, the solid content is increased, the method can enable the solid content to be 80%, the final reaction time is prolonged, the particle size is increased to 2.0-25.0um, the uniform production can be realized, the solution flow can be obtained, the batch production speed is 0.01-2000 h, and the batch production speed is obtained, wherein the solution stirring speed is 100 h, the batch00r/min, the temperature is 30-80 ℃, and the pH is 9-13.5; the protective gas is nitrogen with a flow rate of 0.01-80m³/h。

Wherein the same or different processes comprise solution flow of 0.01-2000L/h, stirring speed of 100-1000 r/min, temperature of 30-80 ℃, pH of 9-13.5, protective gas of nitrogen, and flow of 0.01-80m³/h。

In conclusion, the beneficial effects of the invention are as follows:

the defect of uneven particle size distribution is solved, the compaction density of the material and the -induced property of pole piece coating are improved, the cycle life of the battery core is prolonged, and the polarization of the battery can be reduced to improve the rate capability.

Drawings

FIG. 1 is a schematic view of example 1 in which reaction tank 1 and reaction tank 2 of the present invention are connected;

FIG. 2 is a schematic view of example 2 in which reaction tank 1 and reaction tank 2 are connected according to the present invention;

FIG. 3 is a particle size distribution plot of the final product of the present invention.

In the figure, 1, a reaction kettle 1; 2. a reaction kettle 1; 3. an overflow port.

Detailed Description

For a further understanding of the invention, the invention is further described in conjunction with the description and the specific preferred embodiments, but not intended to limit the scope of the invention.