CN1472828A - Method for improving high-temperature performance of lithium ion battery positive material LiMn2O4 - Google Patents

Method for improving high-temperature performance of lithium ion battery positive material LiMn2O4 Download PDF

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Publication number
CN1472828A
CN1472828A CNA021258287A CN02125828A CN1472828A CN 1472828 A CN1472828 A CN 1472828A CN A021258287 A CNA021258287 A CN A021258287A CN 02125828 A CN02125828 A CN 02125828A CN 1472828 A CN1472828 A CN 1472828A
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limn
lithium ion
high temperature
modifier
ion battery
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CN1234177C (en
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卢世刚
黄松涛
李明勋
刘人敏
吴国良
金维华
蔡振平
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China Automotive Battery Research Institute Co Ltd
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Beijing General Research Institute for Non Ferrous Metals
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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
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1391—Processes of manufacture of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
    • 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
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • 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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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Chemistry (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Secondary Cells (AREA)

Abstract

A method that can improve the high temperature characteristics of the material of Li-ion battery positive electrode, its main characteristic is: take a any kind of lithium salt, metal oxide and hydroxide, or the mixture of the a any kind of lithium salt and a any of metal oxide and hydroxide as modifier to mix with LiMn204, at the temperature of 700 deg.C-900 deg.C react 5-15 hours, get the improved LiMn204. The molar ratio between the modifier and the LiMn204 is 0.05-0.5. This method is simple and reliable, low production cost, shorter production period, easy to operating, the results of improvement are obvious.

Description

Improved lithium ion battery cathode material LiMn2O4Method of high temperature performance of
Technical fieldDomain
The invention relates to a positive electrode material of a lithium ion battery and a preparation method thereof, belonging to the technical field of electrochemistry, inorganic synthesis and electronic products.
Background
At present, LiCoO is mainly adopted in commercial lithium ion batteries2As the anode, but the cobalt resource is poor, the price is high and the pollution is large, because the manganese oxide has the obvious advantages of no toxicity, low cost and high thermal stability, the spinel LiMn2O4Is generally regarded as the most promising replacement for LiCoO2However, the capacity of the material decays rapidly during charge and discharge cycles, which is more serious at high temperatures (55 ℃). How to improve LiMn2O4The cycle performance, particularly the high temperature cycle performance of (C) is related to LiMn2O4The key problem of large-scale application is solved.
For increasing LiMn2O4The high-temperature cycle performance of the method is researched by scholars at home and abroad from different aspects, and the method mainly comprises the following steps:
1 doping
Chen anxuan equidirectional LiMn2O4After a small amount of Li is added, the capacity loss of the material in the charging and discharging process is reduced to 6 percent (55 ℃, 0.2C and 3.40-4.35V) from 24 percent before Li is added. The method is to mix Li according to a certain proportion2CO3Or LiNO3And electrolytic MnO2(EMD) after ball milling and mixing, heating to 800 ℃ in air atmosphere and keeping the temperature for 20 hours, and then slowly cooling to room temperature to obtain a sample. [ Battery, 2001, 31(2), 75-77 []]
Antonini et al LiMn2O4After a small amount of Ga is added, the capacity loss is reduced from 11.6 percent to 9 percent (55 ℃, 0.5C, 3.50-4.35V). The method is to mix Li in a specific proportion2CO3，MnO2And reacting the mixture in air at 730 ℃ for 72 hours after fully and uniformly mixing GaO, and naturally cooling to obtain the sample. [ J.Eiectrochem.Soc, 1998, 145 (8): 2726 to 2732]
2 surface treatment
Such as Amatucci et al, with Lithium Boron Oxide (LBO) on LiMn2O4After coating, the capacity loss at 55 ℃ corresponds only to 44% of the capacity loss before treatment. The method is that Li is firstly added2O、B2O3、ZrO2Mixing with acetone, ball milling for 72h, drying, and mixing with LiMn2O4Reacting the powder at 800 ℃ for 72h, and slowly cooling to room temperature to obtain a sample. [ Solid State Ionics, 1997, 104: 13]
3 improved synthesis process
For example, Guyomard D et al propose that the specific surface area of the material can be reduced, thereby reducing the contact area between the electrode material and the electrolyte. The method can improve LiMn to a certain extent2O4But large particle size may beIt may cause difficulty in diffusion of lithium ions, decrease rate characteristics and discharge capacity of the battery, and may cause easy perforation of the separator due to poor workability of the material. [ J Power Sources, 1995, 54: 92]
Other methods include melt-impregnation methods for the preparation of binary doped spinels [ J Power Sources, 1998, 74: 24]Optimization of spinel and electrolyte combinations [ Abstract for 9]thInternational Meeting onLithium Batteries [C]1998，Poster II Thur 9.]And the like.
It is noted that the improvement of LiMn2O4In the study of the high-temperature cycle performance, most of the researchers in various countries have studied doping, including doping with Al, Cr, Co, Ni, etc. in addition to the above-mentioned doping with Li and Ga, and all doping methods follow the following process:
for the process, the reactants are at least three compounds, so the reaction is complex and is not easy to control. In addition, the reaction time is long, which results in low production efficiency.
Technical content
The invention aims to provide a method which has simple and reliable process, low production cost, short period, easy operation and improved effectObviously improves the LiMn which is the anode material of the lithium ion battery2O4The high temperature cycle performance of (1).
In order to achieve the purpose, the invention adopts the following technical scheme: any one of lithium salt, metal oxide and hydroxide or a mixture of any one of lithium salt and any one of metal oxide and hydroxide is used as a modifier to react with LiMn2O4Mixing, and reacting at 700-900 ℃ for 5-15 hours to obtain modified LiMn2O4。
It is prepared by LiMn2O4The high-temperature solid-phase reaction with the modifier is carried out, and the technical process is as follows:
compared with the doping method, the method has the advantages of simple and reliable process, low production cost, short period, easy operation, obvious improvement effect and the like.
Wherein the lithium salt may be Li2CO3、LiNO3LiF, LiCl, etc., the metal oxide or hydroxide may be CO3O4、Al2O3、Cr2O3、Al(OH)3、Co(OH)3And the like.
In the presence of the modifier and LiMn2O4When mixing, wherein the modifier is mixed with LiMn2O4The molar ratio of (A) to (B) is 0.05 to 0.5.
The method of the invention is to improve LiMn2O4By means of LiMn2O4High temperature solid phase reaction with a modifier.
Drawings
FIG. 1 shows LiMn before and after modification in example 12O4Comparative graph of high temperature cycle performance.
FIG. 2 shows LiMn before and after modification in example 22O4Comparative graph of high temperature cycle performance.
FIG. 3 shows L before and after modification in example 3iMn2O4Comparative graph of high temperature cycle performance.
FIG. 4 shows LiMn before and after modification in example 42O4Comparative graph of high temperature cycle performance.
FIG. 5 shows LiMn before and after modification in example 52O4Comparative graph of high temperature cycle performance.
FIG. 6 shows LiMn before and after modification in example 62O4Comparative graph of high temperature cycle performance.
FIG. 7 shows LiMn before and after modification in example 72O4Comparative graph of high temperature cycle performance.
FIG. 8 shows LiMn before and after modification in example 82O4Comparative graph of high temperature cycle performance.
Detailed Description
Example 1: with Li2CO3For LiMn2O4Is modified
According to Li2CO3/LiMn2O4Accurately weighing certain Li (molar ratio) of 0.062CO3And LiMn2O4And mixing the materials in a mixer for 5 hours, putting the mixture into a muffle furnace, reacting for 10 hours at 850 ℃, naturally cooling, taking out the product, grinding, and sieving by a 300-mesh sample sieve to obtain a sample.
The sample is uniformly mixed with acetylene black, graphite and PVDF according to a certain proportion, then is mixed into slurry, and is coated on Al foil to prepare an experimental electrode with the thickness of 10 mm. The experimental cell adopts a two-electrode electrolytic cell, the counter electrode is metal lithium, and the electrolyte is LiPF6And the electrochemical test adopts a constant current charge-discharge method (0.1C, 3.3-4.35V) to test the capacity and the cycle performance of the material at high temperature.
After 20 weeks of circulation, the modified LiMn is obtained2O4The capacity loss at high temperature was reduced from 26.7% to 5.4% before modification, as shown in FIG. 1, LiMn2O4The high-temperature cycle performance of the catalyst is remarkably improved.
Example 2: LiF to LiMn2O4Is modified
According to LiF/LiMn2O4Several grams of LiF and LiMn were weighed out as 0.052O4Samples were prepared and tested in the same manner as in example 1. After 20 weeks of circulation, the modified LiMn is obtained2O4The capacity loss at high temperature was 15.5%, which was 58.1% before modification, as shown in FIG. 2, LiMn2O4The high-temperature cycle performance of the catalyst is improved to a certain extent.
Example 3: by Co3O4For LiMn2O4Is modified
According to Co3O4/LiMn2O4Several grams of Co were weighed 0.27 ═ 0.273O4And LiMn2O4Samples were prepared and tested in exactly the same procedure as in example 1. After 20 weeks of circulation, the modified LiMn is obtained2O4The capacity loss at high temperature was 14.6%, which was 54.7% before modification, as shown in FIG. 3, LiMn2O4The high-temperature cycle performance of the catalyst is improved to a certain extent.
Example 4: with Al2O3For LiMn2O4Is modified
According to Al2O3/LiMn2O4Several grams of Al are weighed out 0.112O3And LiMn2O4Samples were prepared and tested in exactly the same procedure as in example 1. After 20 weeks of circulation, the modified LiMn is obtained2O4The capacity loss at high temperature of (2) was 10.2%, and as shown in FIG. 4, itwas 38.2% before modification, and LiMn2O4The high-temperature cycle performance of the catalyst is obviously improved.
Example 5: with Al (OH)3For LiMn2O4Is modified
According to Al (OH)3/LiMn2O4Several grams of Al (OH) were weighed out as 0.153And LiMn2O4Samples were prepared and tested in exactly the same procedure as in example 1. After 20 weeks of circulation, the modified LiMn is obtained2O4The capacity loss at high temperature of (2) is 7.6%As shown in FIG. 5, the percent of LiMn was 37.8% before modification2O4High temperature ofThe cycle performance is obviously improved.
Example 6: with Al2O3+ LiF vs LiMn2O4Is modified
According to Al2O3/LiMn2O40.11 while LiF/LiMn2O4Several grams of Al are weighed 0.22 ═ 0.222O3LiF and LiMn2O4Samples were prepared and tested in the same manner as in example 1. After 20 weeks of circulation, the modified LiMn is obtained2O4The capacity loss at high temperature was 5.8%, and as shown in FIG. 6, it was 21.7% before modification, and LiMn2O4The high-temperature cycle performance of the high-temperature cycle is greatly improved.
Example 7: with Al (OH)3+ LiF vs LiMn2O4Is modified
According to Al (OH)3/LiMn2O40.06, simultaneously using LiF/LiMn2O4Several grams of Al (OH) were weighed 0.063LiF and LiMn2O4Samples were prepared and tested in the same manner as in example 1. After 20 weeks of circulation, the modified LiMn is obtained2O4The capacity loss of (2.9%) was 10.9% before modification, and LiMn was contained as shown in FIG. 72O4The high-temperature cycle performance of the catalyst is remarkably improved.
Example 8: with Cr2O3+ LiF vs LiMn2O4Is modified
According to Cr2O3/LiMn2O40.11 while LiF/LiMn2O4Several grams of Cr were weighed out as 0.062O3LiF and LiMn2O4Samples were prepared and tested in the same manner as in example 1. After 20 weeks of circulation, the modified LiMn is obtained2O4The capacity loss of (2) was 6.1%, and as shown in FIG. 8, it was 22.8% before modification, and LiMn was effectively improved2O4High temperature cycle performance of.
The embodiment shows that the method has the remarkable advantages of simple and reliable process, low production cost, short period, easiness in operation, obvious improvement effect and the like.

Claims (3)

1. Improved lithium ion battery cathode material LiMn2O4The method for high temperature performance of (1), characterized by: any one of lithium salt, metal oxide and hydroxide or a mixture of any one of lithium salt and any one of metal oxide and hydroxide is used as a modifier to react with LiMn2O4Mixing, and reacting at 700-900 ℃ for 5-15 hours to obtain modified LiMn2O4。
2. The positive electrode material LiMn for lithium ion batteries according to claim 12O4The method for modifying (2), characterized in that: the lithium salt may be Li2CO3、LiNO3LiF, LiCl; the metal oxide or hydroxide may be Co3O4、Al2O3、Cr2O3、Al(OH)3、Co(OH)3。
3. The positive electrode material LiMn for lithium ion batteries according to claim 1 or 22O4The method for modifying (2), characterized in that: in the presence of the modifier and LiMn2O4When mixing, the modifier is mixed with LiMn2O4The molar ratio of (A) to (B) is 0.05 to 0.5.
CNB021258287A 2002-07-30 2002-07-30 Method for improving high-temperature performance of lithium ion battery positive material LiMn2O4 Expired - Lifetime CN1234177C (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102201572A (en) * 2010-03-25 2011-09-28 青岛新正锂业有限公司 LiMn2-xMxO4.yLiAlO2 as anode material for lithium ion battery
CN102664254A (en) * 2012-05-25 2012-09-12 青岛乾运高科新材料股份有限公司 Method for preparing composite dopant LiMn2O4 by one-step sintering solid-phase reaction
CN104269549A (en) * 2014-09-04 2015-01-07 江苏大学 Lithium manganate battery
CN104350636A (en) * 2012-07-09 2015-02-11 株式会社Lg化学 High voltage anode active material and lithium secondary battery including same
CN106129375A (en) * 2016-08-30 2016-11-16 四川大学 A kind of method of compound lithium salts modified electrode material
CN108493441A (en) * 2018-02-11 2018-09-04 山东联星能源集团有限公司 A kind of positive plate and preparation method thereof for lithium ion battery

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102694167B (en) * 2011-08-30 2014-12-24 中国科学院宁波材料技术与工程研究所 Modified lithium manganate positive pole material and preparation method thereof

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102201572A (en) * 2010-03-25 2011-09-28 青岛新正锂业有限公司 LiMn2-xMxO4.yLiAlO2 as anode material for lithium ion battery
CN102664254A (en) * 2012-05-25 2012-09-12 青岛乾运高科新材料股份有限公司 Method for preparing composite dopant LiMn2O4 by one-step sintering solid-phase reaction
CN102664254B (en) * 2012-05-25 2014-12-31 青岛乾运高科新材料股份有限公司 Method for preparing composite dopant LiMn2O4 by one-step sintering solid-phase reaction
CN104350636A (en) * 2012-07-09 2015-02-11 株式会社Lg化学 High voltage anode active material and lithium secondary battery including same
US9799878B2 (en) 2012-07-09 2017-10-24 Lg Chem, Ltd. High voltage positive active material and lithium secondary battery comprising the same
CN104269549A (en) * 2014-09-04 2015-01-07 江苏大学 Lithium manganate battery
CN106129375A (en) * 2016-08-30 2016-11-16 四川大学 A kind of method of compound lithium salts modified electrode material
CN106129375B (en) * 2016-08-30 2019-02-22 四川大学 A kind of method of compound lithium salts modified electrode material
CN108493441A (en) * 2018-02-11 2018-09-04 山东联星能源集团有限公司 A kind of positive plate and preparation method thereof for lithium ion battery

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