CN110707361B - Electrolyte for high-voltage soft-package lithium ion battery suitable for high-rate charge and discharge - Google Patents
Electrolyte for high-voltage soft-package lithium ion battery suitable for high-rate charge and discharge Download PDFInfo
- Publication number
- CN110707361B CN110707361B CN201911039682.6A CN201911039682A CN110707361B CN 110707361 B CN110707361 B CN 110707361B CN 201911039682 A CN201911039682 A CN 201911039682A CN 110707361 B CN110707361 B CN 110707361B
- Authority
- CN
- China
- Prior art keywords
- ion battery
- lithium ion
- electrolyte
- lithium
- additive
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- 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
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0566—Liquid materials
- H01M10/0567—Liquid materials characterised by the additives
-
- 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2300/00—Electrolytes
- H01M2300/0017—Non-aqueous electrolytes
- H01M2300/0025—Organic electrolyte
-
- 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
Abstract
The invention provides electrolyte for a high-voltage soft package lithium ion battery suitable for high-rate charge and discharge, which comprises a positive electrode protection additive 3-methoxypropionitrile and/or adiponitrile, a negative electrode film-forming additive fluoroethylene carbonate, a high-temperature additive 1, 3-propane sultone and a low-impedance additive ethylene sulfate and/or lithium difluorophosphate. The high-voltage lithium ion battery prepared by optimally combining the anode and cathode materials, the pole piece design and the electrolyte formula has excellent high-rate cycle life. According to the invention, the additive 3-methoxypropionitrile and the low-impedance additive are added into the electrolyte, so that the high-voltage lithium ion battery suitable for high-rate charge and discharge has excellent high-temperature storage and low-temperature discharge performance. The 3-methoxypropionitrile has complexation with positive metal ions to inhibit the decomposition of electrolyte and the dissolution of metal ions, and the formed membrane has low impedance to ensure the extraction and insertion of lithium ions.
Description
Technical Field
The invention belongs to the technical field of lithium ion batteries, and particularly relates to electrolyte for a high-voltage soft package lithium ion battery, which is suitable for high-rate charge and discharge.
Background
In recent years, lithium ion batteries have been widely used in the fields of smart phones, tablet computers, smart wearing, electric tools, electric automobiles, and the like. With the acceleration of life rhythm and the development of electronic products, the demands of consumers on shortening the charging time and improving the energy density of the lithium ion battery are more urgent, and correspondingly higher requirements on the charging speed and voltage of the lithium ion battery are provided; meanwhile, the lithium ion battery is required to have a long service life and high safety.
Therefore, there is a need to develop an electrolyte for a high-voltage soft-package lithium ion battery with a long cycle life at a high rate, and the lithium ion battery formed by the electrolyte has good storage and low-temperature charge and discharge properties.
Disclosure of Invention
The factors influencing the high-rate charge and discharge performance of the lithium ion battery mainly comprise positive and negative electrode materials, electrolyte, a battery cell structure design and the like, wherein the positive and negative electrode materials and the electrolyte are important for the high-rate charge and discharge performance of the lithium ion battery. On one hand, the lithium ion battery uses the anode and cathode materials which can rapidly remove/embed lithium during charging and discharging, so that the problems of capacity attenuation and safety caused by lithium precipitation in the battery cell are avoided; on the other hand, the lithium ion battery electrolyte with low viscosity, high conductivity and excellent dynamic performance is designed, and meanwhile, the electrolyte can form a solid electrolyte interface film with low resistance on the surfaces of a positive electrode and a negative electrode, so that the lithium ions can be rapidly transferred in the electrolyte.
In order to overcome the defects in the prior art, the invention provides the electrolyte for the high-voltage soft package lithium ion battery suitable for high-rate charge and discharge, and the lithium ion battery has excellent cycle performance under high rate and also has good storage and low-temperature charge and discharge performance.
In order to achieve the purpose, the invention adopts the following technical scheme:
the non-aqueous electrolyte for the high-voltage soft package lithium ion battery suitable for high-rate charge and discharge comprises a non-aqueous organic solvent, an additive and a lithium salt, wherein the additive comprises a positive electrode protection additive 3-methoxypropionitrile and/or adiponitrile, a negative electrode film forming additive fluoroethylene carbonate, a high-temperature additive 1, 3-propane sultone and a low-impedance additive ethylene sulfate and/or lithium difluorophosphate.
The non-aqueous organic solvent is a mixture of at least one cyclic carbonate and at least one of linear carbonate and linear carboxylate in any proportion, and is suitable for the electrolyte for the high-voltage soft package lithium ion battery with high-rate charge and discharge.
Wherein, the cyclic carbonate is selected from at least one of ethylene carbonate and propylene carbonate, the linear carbonate is selected from at least one of dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate, and the linear carboxylate is selected from at least one of ethyl propionate, propyl propionate and propyl acetate.
The nonaqueous organic solvent is taken as 100 percent of the total volume, wherein the volume fraction of the cyclic carbonate is 15-40vol percent, and the volume fraction of the linear carbonate and/or the linear carboxylic ester is 60-85vol percent.
The content of the 3-methoxypropionitrile in the electrolyte for the high-voltage soft-package lithium ion battery, which is suitable for high-rate charge and discharge, is 0.5 to 4 wt.%, for example, 0.5 wt.%, 0.6 wt.%, 0.8 wt.%, 1 wt.%, 2 wt.%, 3 wt.% or 4 wt.% of the total mass of the nonaqueous electrolyte.
The content of adiponitrile in the electrolyte for the high-voltage soft-package lithium ion battery, which is suitable for high-rate charge and discharge, is 0.5 to 4 wt.%, for example, 0.5 wt.%, 0.6 wt.%, 0.8 wt.%, 1 wt.%, 2 wt.%, 3 wt.% or 4 wt.% of the total mass of the nonaqueous electrolyte.
The content of the fluoroethylene carbonate is 6 to 15 wt.%, for example, 6 wt.%, 7 wt.%, 8 wt.%, 9 wt.%, 10 wt.%, 11 wt.%, 12 wt.%, 13 wt.%, 14 wt.% or 15 wt.% of the total mass of the nonaqueous electrolyte solution, as the electrolyte solution for the high-voltage soft-pack lithium ion battery, which is suitable for high-rate charge and discharge according to the present invention.
The content of the 1, 3-propane sultone is 3.5-5 wt.%, for example, 3.5 wt.%, 4 wt.%, 4.5 wt.% or 5 wt.% of the total mass of the nonaqueous electrolyte solution, which is used as the electrolyte solution for the high-voltage soft-package lithium ion battery and is suitable for high-rate charge and discharge.
As the electrolyte for the high-voltage soft-package lithium ion battery suitable for high-rate charge and discharge, the content of the ethylene sulfate and/or the lithium difluorophosphate is 0.2 to 3 wt.%, for example, 0.2 wt.%, 0.5 wt.%, 0.8 wt.%, 1 wt.%, 1.5 wt.%, 2 wt.%, 2.5 wt.%, or 3 wt.% of the total mass of the nonaqueous electrolyte.
As the electrolyte for the high-voltage soft-package lithium ion battery suitable for high-rate charge and discharge, the lithium salt is selected from any one or more of lithium bis (trifluoromethylsulfonyl) imide, lithium bis (fluorosulfonyl) imide and lithium hexafluorophosphate, and accounts for 13-18 wt.%, such as 13 wt.%, 14 wt.%, 15 wt.%, 16 wt.%, 17 wt.% and 18 wt.% of the total mass of the electrolyte.
As the electrolyte for the high-voltage soft package lithium ion battery suitable for high-rate charge and discharge, the non-aqueous electrolyte also comprises one or more than two of ethylene carbonate, ethylene glycol bis (propionitrile) ether, 1,2, 3-tris (2-cyanoethoxy) propane, lithium bis (oxalato) borate and lithium difluoro (oxalato) borate; which accounts for 0-5 wt.% of the total mass of the electrolyte.
The invention also provides a preparation method of the electrolyte for the high-voltage soft package lithium ion battery suitable for high-rate charge and discharge, which comprises the step of mixing a non-aqueous organic solvent, an additive and a lithium salt, wherein the additive comprises a positive electrode protection additive 3-methoxypropionitrile, a negative electrode film forming additive fluoroethylene carbonate, a high-temperature additive 1, 3-propane sultone and a low-impedance additive ethylene sulfate and/or lithium difluorophosphate.
The invention also provides a high-voltage soft package lithium ion battery suitable for high-rate charge and discharge, which comprises the non-aqueous electrolyte.
The high-voltage soft package lithium ion battery suitable for high-rate charge and discharge further comprises a positive plate, a negative plate and a diaphragm arranged between the positive plate and the negative plate; the positive plate comprises a positive current collector and a mixed layer of a positive active material, a conductive agent and a binder coated on the positive current collector; the negative plate comprises a positive current collector and a mixed layer of a negative active material, a conductive agent and a binder coated on the positive current collector;
as the high-voltage soft package lithium ion battery suitable for high-rate charge and discharge, the positive active material is lithium cobaltate subjected to doping and coating treatment by one or more elements of Al, Mg, Ti and Zr, and the median particle diameter D5010-26 μm, and specific surface area of 0.1-0.4m2(ii) in terms of/g. When the anode material is coated, the compacted density of the anode material is 3.8-4.4mg/cm3。
Adapted for high rate charging and discharging as the inventionThe negative active material is graphite or a graphite composite material containing 1-10 wt.% SiOx/C or Si/C, wherein the median particle diameter D50The value is 8-25 μm, and the specific surface area is 0.7-5.0m2(ii)/g; when the negative electrode material is coated, the compacted density of the negative electrode material is 1.5-1.75mg/cm3。
The high-voltage soft package lithium ion battery suitable for high-rate charge and discharge comprises a substrate and a composite layer of inorganic particles and polymers coated on the substrate, wherein the thickness of the composite layer is 1-6 mu m.
As the high-voltage soft package lithium ion battery applicable to high-rate charge and discharge, the composite layer of the inorganic particles and the polymer is a mixture of titanium oxide and polyvinylidene fluoride-hexafluoropropylene copolymer.
The high-voltage soft package lithium ion battery is suitable for high-rate charge and discharge, and the charge cut-off voltage of the lithium ion battery is 4.4V or more.
The invention has the beneficial effects that:
the invention provides an electrolyte for a high-voltage soft package lithium ion battery, which is suitable for high-rate charge and discharge, and has the following advantages:
1. the high-voltage lithium ion battery prepared by optimally combining the anode and cathode materials, the pole piece design and the electrolyte formula has excellent high-rate cycle life.
2. According to the invention, the additive 3-methoxypropionitrile and the low-impedance additive are added into the electrolyte, so that the high-voltage lithium ion battery suitable for high-rate charge and discharge has excellent high-temperature storage and low-temperature discharge performance. The 3-methoxypropionitrile has complexation with positive metal ions to inhibit the decomposition of electrolyte and the dissolution of metal ions, and the formed membrane has low impedance to ensure the extraction and insertion of lithium ions.
Detailed Description
The preparation method of the present invention will be described in further detail with reference to specific examples. It is to be understood that the following examples are only illustrative and explanatory of the present invention and should not be construed as limiting the scope of the present invention. All the technologies realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.
The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, materials and the like used in the following examples are commercially available unless otherwise specified.
Example 1
Preparing a positive plate: dispersing a positive electrode active material Ti element doped lithium cobaltate, conductive carbon black and a binder polyvinylidene fluoride (PVDF) in a proper amount of N-methylpyrrolidone (NMP) solvent according to a mass ratio of 97:1.5:1.5, and fully stirring and mixing to form uniform positive electrode slurry; and uniformly coating the positive slurry on a positive current collector aluminum foil, and drying, rolling and slitting to obtain the positive plate.
Preparing a negative plate: dispersing a negative electrode active material artificial graphite, conductive carbon black, a binder Styrene Butadiene Rubber (SBR) and a thickener sodium carboxymethyl cellulose (CMC-Na) in a proper amount of deionized water solvent according to a mass ratio of 96.5:0.5:1.5:1.5, and fully stirring and mixing to form uniform negative electrode slurry; and uniformly coating the negative electrode slurry on a copper foil of a negative current collector, and drying, rolling and slitting to obtain a negative plate.
Preparing a diaphragm: a polyethylene separator having a thickness of 7 μm was coated with a 2 μm thick composite layer of a mixture of titanium oxide and polyvinylidene fluoride-hexafluoropropylene copolymer.
Preparation of nonaqueous electrolyte: in a glove box filled with argon (moisture)<10ppm, oxygen content<1ppm), Ethylene Carbonate (EC), Propylene Carbonate (PC), Propyl Propionate (PP), Ethyl Propionate (EP) were mixed uniformly in a mass ratio of 20:10:50:20, and LiPF of 14 wt.% based on the total mass of the nonaqueous electrolyte was slowly added to the mixed solution6The mixture was stirred until it was completely dissolved, and then 6 wt.% of fluoroethylene carbonate, 4 wt.% of 1, 3-propanesulfonic acid lactone, 1 wt.% of adiponitrile, 0.5 wt.% of 3-methoxypropionitrile, and 0.5 wt.% of lithium difluorophosphate were added in this order based on the total mass of the nonaqueous electrolytic solution, to obtain the lithium ion battery electrolyte of example 1.
Preparing a high-voltage lithium ion battery: and winding the prepared positive plate, the diaphragm and the prepared negative plate to obtain a naked battery cell, and packaging the battery cell into an aluminum plastic film bag formed in a stamping manner in advance. And (3) after the packaged battery is dried at 85 ℃, injecting the prepared nonaqueous electrolytic solution into the dried battery, and finishing the preparation of the lithium ion battery after the battery is laid aside, formed and sealed for the second time.
Example 2
Unlike example 1, the electrolyte was prepared by adding 6 wt.% fluoroethylene carbonate, 4 wt.% 1, 3-propanesulfonic lactone, 1 wt.% adiponitrile, 1 wt.% 3-methoxypropionitrile, and 0.5 wt.% lithium difluorophosphate, based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Example 3
Different from the embodiment 1, the electrolyte is prepared by adding 6 wt.% of fluoroethylene carbonate, 4 wt.% of 1, 3-propane sulfonic lactone, 1 wt.% of adiponitrile, 2 wt.% of 3-methoxypropionitrile and 0.5 wt.% of lithium difluorophosphate based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Example 4
Different from the embodiment 1, the electrolyte is prepared by adding 6 wt.% of fluoroethylene carbonate, 4 wt.% of 1, 3-propane sulfonic lactone, 1 wt.% of adiponitrile, 4 wt.% of 3-methoxypropionitrile and 0.5 wt.% of lithium difluorophosphate based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Example 5
Unlike example 1, 8 wt.% fluoroethylene carbonate, 4 wt.% 1, 3-propanesulfonic lactone, 1 wt.% adiponitrile, 2 wt.% 3-methoxypropionitrile, and 0.5 wt.% lithium difluorophosphate were added to the preparation of the electrolyte, based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Example 7
Different from the embodiment 1, the electrolyte is prepared by adding 6 wt.% of fluoroethylene carbonate, 4 wt.% of 1, 3-propane sulfonic lactone, 1 wt.% of adiponitrile, 2 wt.% of 3-methoxypropionitrile and 0.2 wt.% of lithium difluorophosphate based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Example 8
Unlike example 1, the electrolyte was prepared by adding 6 wt.% fluoroethylene carbonate, 4 wt.% 1, 3-propanesulfonic lactone, 1 wt.% adiponitrile, 2 wt.% 3-methoxypropionitrile, and 1 wt.% lithium difluorophosphate, based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Example 9
Different from the embodiment 1, 7 wt.% of fluoroethylene carbonate, 4 wt.% of 1, 3-propane sulfonic lactone, 1 wt.% of adiponitrile, 2 wt.% of 3-methoxypropionitrile, 0.5 wt.% of lithium difluorophosphate and 0.5 wt.% of ethylene sulfate are added in the preparation of the electrolyte based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Example 10
Unlike example 1, one is that the negative active material in the preparation of the negative electrode sheet was a composite of artificial graphite and 5% SiO/C material.
Secondly, 10 wt.% of fluoroethylene carbonate, 5 wt.% of 1, 3-propane sulfonic lactone, 1 wt.% of adiponitrile, 2 wt.% of 3-methoxypropionitrile and 0.5 wt.% of lithium difluorophosphate are added in the preparation of the electrolyte based on the total mass of the non-aqueous electrolyte. The rest is the same as in example 1.
Example 11
Unlike example 10, 10 wt.% fluoroethylene carbonate, 5 wt.% 1, 3-propanesulfonic acid lactone, 1 wt.% adiponitrile, 2 wt.% 3-methoxypropionitrile, 0.5 wt.% lithium difluorophosphate, and 1 wt.% ethylene sulfate were added to the preparation of the electrolyte, based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 10.
Example 12
Unlike example 10, 12 wt.% fluoroethylene carbonate, 5 wt.% 1, 3-propanesulfonic acid lactone, 1 wt.% adiponitrile, 2 wt.% 3-methoxypropionitrile, 0.5 wt.% lithium difluorophosphate, and 1 wt.% ethylene sulfate were added to the preparation of the electrolyte, based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 10.
Comparative example 1
Unlike example 1, fluoroethylene carbonate was added to the preparation of the electrolyte in an amount of 6 wt.% based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Comparative example 2
Unlike example 1, adiponitrile 1 wt.% and fluoroethylene carbonate 6 wt.% were added to the electrolyte preparation based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Comparative example 3
Unlike example 1, adiponitrile 1 wt%, fluoroethylene carbonate 6 wt%, and 1, 3-propane sulfonic acid lactone 4 wt% based on the total mass of the nonaqueous electrolyte were added to the electrolyte. The rest is the same as in example 1.
Comparative example 4
Unlike example 1, adiponitrile 1 wt%, fluoroethylene carbonate 6 wt%, 1, 3-propanesulfonic acid lactone 4 wt%, and 3-methoxypropionitrile 4 wt%, based on the total mass of the nonaqueous electrolyte, were added to the electrolyte preparation. The rest is the same as in example 1.
Comparative example 5
Unlike example 1, adiponitrile 1 wt.%, fluoroethylene carbonate 6 wt.%, 1, 3-propanesulfonic acid lactone 4 wt.%, and lithium difluorophosphate 0.5 wt.% were added to the electrolyte preparation, based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
Comparative example 6
Unlike example 1, adiponitrile 1 wt.%, fluoroethylene carbonate 6 wt.%, 1, 3-propanesulfonic acid lactone 4 wt.%, and lithium difluorophosphate 2 wt.% were added to the electrolyte preparation, based on the total mass of the nonaqueous electrolyte. The rest is the same as in example 1.
The cells obtained in the above comparative examples and examples were subjected to electrochemical performance tests, as described below:
25 ℃ cycling experiment: the batteries obtained in the above examples and comparative examples were placed in an environment of (25 ± 2) ° C, left for 2-3 hours, and when the battery body reached (25 ± 2) ° C, the battery was charged at a constant current of 0.025C at 3C, left for 5 minutes after being fully charged, and then discharged at a constant current of 0.7C to a cut-off voltage of 3.0V, and the maximum discharge capacity of the previous 3 cycles was recorded as an initial capacity Q, and when the cycles reached the required number, the last discharge capacity Q1 of the battery was recorded, and the results were recorded as in table 1.
The calculation formula used therein is as follows: capacity retention (%) ═ Q1/Q × 100%.
High temperature storage experiment: the cells obtained in the above examples and comparative examples were subjected to a charge-discharge cycle test at room temperature for 3 times at a charge-discharge rate of 0.5C, and then a 0.5C constant current charge cutoff current was 0.025C and charged to a full charge state, and the maximum discharge capacity Q and the cell thickness T of the previous 3 0.5C cycles were recorded, respectively. The battery in a full-charge state is stored for 6 hours at 85 ℃, the thickness T0 and the discharge capacity Q1 of 0.5C after 6 hours are recorded, then the battery is charged and discharged for 3 times at the room temperature at the rate of 0.5C, the maximum discharge capacity Q2 of 3 cycles is recorded, experimental data such as the thickness change rate, the capacity retention rate and the capacity recovery rate of the battery stored at high temperature are obtained through calculation, and the recording results are shown in table 1.
The calculation formula used therein is as follows: thickness change rate (%) - (T0-T)/T × 100%; capacity retention (%) ═ Q1/Q × 100%; capacity recovery (%) - (-) Q2/Q.times.100%.
Low-temperature discharge experiment: discharging the batteries obtained in the above examples and comparative examples to 3.0V at ambient temperature of 25 + -3 deg.C at 0.2C, and standing for 5 min; and (3) charging at 0.7C, changing constant voltage charging when the voltage at the cell terminal reaches the charging limiting voltage, stopping charging until the charging current is less than or equal to the cut-off current, discharging to 3.0V at 0.2C after standing for 5 minutes, and recording the discharge capacity at the current time as the normal-temperature capacity Q0. Then the battery cell is charged at 0.7C, when the voltage of the battery cell terminal reaches the charging limiting voltage, constant voltage charging is changed, and charging is stopped until the charging current is less than or equal to the cut-off current; after the fully charged battery is placed for 4 hours at the temperature of minus 20 +/-2 ℃, the battery is discharged to the cut-off voltage of 3.0V by the current of 0.2C, the discharge capacity Q3 is recorded, the low-temperature discharge capacity retention rate can be obtained by calculation, and the recording result is shown in table 1.
The calculation formula used therein is as follows: the low-temperature discharge capacity retention (%) ═ Q3/Q0 × 100%.
Table 1 results of normal temperature cycle, high temperature storage and low temperature discharge test of batteries obtained in examples and comparative examples
As can be seen from the results of table 1:
as can be seen from comparative examples 3-4, the addition of 3-methoxypropionitrile to the electrolyte can significantly improve the cycle and high-temperature storage properties of the battery; it can be seen from comparative examples 3 and 5 to 6 that the addition of lithium difluorophosphate can significantly improve the low-temperature discharge performance of the battery. As can be seen from comparison of example 3 with comparative examples 1 to 6, the battery of example 3, which contains fluoroethylene carbonate, 1, 3-propane sultone, 3-methoxypropionitrile, and lithium difluorophosphate together, has better fast charge cycle performance, storage, and low-temperature discharge performance. Further, by comparing each example with comparative examples 1 to 6, it can be found that the optimized combination of the additives fluoroethylene carbonate, 1, 3-propane sultone, 3-methoxypropionitrile and lithium difluorophosphate can obviously improve the fast charge cycle performance and the storage performance of the high-voltage lithium ion battery, and simultaneously has good low-temperature discharge performance.
In summary, the non-aqueous electrolyte for the high-voltage lithium ion battery provided by the invention contains additives of fluoroethylene carbonate, 1, 3-propane sultone, 3-methoxypropionitrile, adiponitrile and lithium difluorophosphate, and further can be added with various additives of ethylene carbonate, ethylene glycol bis (propionitrile) ether, 1,2, 3-tris (2-cyanoethoxy) propane, lithium bis (oxalato) borate, lithium difluorooxalato borate and the like for optimization combination, so that the high-voltage lithium ion battery can have excellent fast charge cycle, storage and low-temperature discharge performance through solvent optimization and synergistic action among the additives.
The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. A high-voltage soft package lithium ion battery suitable for 3C rate charge and discharge comprises a non-aqueous electrolyte, wherein the non-aqueous electrolyte comprises a non-aqueous organic solvent, an additive and a lithium salt, the additive comprises a positive electrode protection additive, namely 3-methoxypropionitrile and adiponitrile, a negative electrode film forming additive, namely fluoroethylene carbonate, a high-temperature additive, namely 1, 3-propane sultone, and a low-resistance additive, namely ethylene sulfate and/or lithium difluorophosphate;
the lithium ion battery also comprises a positive plate, a negative plate and a diaphragm arranged between the positive plate and the negative plate; the positive plate comprises a positive current collector and a mixed layer of a positive active material, a conductive agent and a binder coated on the positive current collector; the negative plate comprises a negative current collector and a mixed layer of a negative active material, a conductive agent and a binder coated on the negative current collector;
the positive active material is lithium cobaltate subjected to Ti doping treatment;
the charge cut-off voltage of the lithium ion battery is 4.4V or more.
2. The lithium ion battery according to claim 1, wherein the non-aqueous organic solvent is selected from a mixture of at least one of cyclic carbonates and at least one of linear carbonates and linear carboxylates, in any proportion;
the cyclic carbonate is selected from at least one of ethylene carbonate and propylene carbonate, the linear carbonate is selected from at least one of dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate, and the linear carboxylate is selected from at least one of ethyl propionate, propyl propionate and propyl acetate.
3. The lithium ion battery according to claim 2, wherein the non-aqueous organic solvent is 100% by volume, wherein the volume fraction of the cyclic carbonate is 15 to 40 vol%, and the volume fraction of the linear carbonate and/or the linear carboxylate is 60 to 85 vol%.
4. The lithium ion battery according to claim 1, wherein the content of the 3-methoxypropionitrile is 0.5 to 4 wt.% of the total mass of the nonaqueous electrolytic solution;
the content of the adiponitrile is 0.5-4 wt% of the total mass of the nonaqueous electrolyte.
5. The lithium ion battery of claim 1, wherein the fluoroethylene carbonate is present in an amount of 6 to 15 wt.% based on the total mass of the nonaqueous electrolyte solution;
the content of the 1, 3-propane sultone is 3.5-5 wt.% of the total mass of the nonaqueous electrolyte;
the content of the ethylene sulfate and/or the lithium difluorophosphate is 0.2 to 3 wt.% of the total mass of the nonaqueous electrolyte.
6. The nonaqueous electrolytic solution of claim 1, wherein the lithium salt is selected from any one of lithium bistrifluoromethylsulfonyl imide, lithium bifluorosulfonimide and lithium hexafluorophosphate, and is present in an amount of 13 to 18 wt.% based on the total mass of the electrolytic solution.
7. The lithium ion battery according to claim 1, wherein the nonaqueous electrolytic solution further comprises one or more of ethylene carbonate, ethylene glycol bis (propionitrile) ether, 1,2, 3-tris (2-cyanoethoxy) propane, lithium bis (oxalato) borate, and lithium difluoro (oxalato) borate; which accounts for 0-5 wt.% of the total mass of the electrolyte.
8. The lithium ion battery according to claim 1, wherein the positive electrode active material has a median particle diameter D5010-26 μm, and specific surface area of 0.1-0.4m2(ii)/g; when the anode material is coated, the compacted density of the anode material is 3.8-4.4mg/cm3；
The negative active material is graphite or graphite composite material containing 1-10 wt.% SiOx/C or Si/C, wherein the median particle diameter D50The value is 8-25 μm, and the specific surface area is 0.7-5.0m2(ii)/g; when the negative electrode material is coated, the compacted density of the negative electrode material is 1.5-1.75mg/cm3。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911039682.6A CN110707361B (en) | 2019-10-29 | 2019-10-29 | Electrolyte for high-voltage soft-package lithium ion battery suitable for high-rate charge and discharge |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911039682.6A CN110707361B (en) | 2019-10-29 | 2019-10-29 | Electrolyte for high-voltage soft-package lithium ion battery suitable for high-rate charge and discharge |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110707361A CN110707361A (en) | 2020-01-17 |
| CN110707361B true CN110707361B (en) | 2021-10-26 |
Family
ID=69203797
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911039682.6A Active CN110707361B (en) | 2019-10-29 | 2019-10-29 | Electrolyte for high-voltage soft-package lithium ion battery suitable for high-rate charge and discharge |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110707361B (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111244546B (en) * | 2020-01-20 | 2021-08-17 | 珠海冠宇电池股份有限公司 | Electrolyte for lithium ion battery suitable for quick charging and lithium ion battery |
| CN111640982B (en) * | 2020-05-18 | 2021-10-26 | 珠海冠宇电池股份有限公司 | Electrolyte for lithium ion battery and lithium ion battery comprising same |
| CN111640984A (en) * | 2020-05-18 | 2020-09-08 | 珠海冠宇电池股份有限公司 | Lithium ion finished product battery and preparation method thereof |
| CN111640986B (en) * | 2020-05-28 | 2021-05-25 | 珠海冠宇电池股份有限公司 | High-safety electrolyte suitable for high-energy-density lithium ion battery |
| CN111900480A (en) * | 2020-08-21 | 2020-11-06 | 珠海冠宇电池股份有限公司 | High-voltage lithium ion battery with excellent high and low temperature performance |
| CN111900479A (en) * | 2020-08-21 | 2020-11-06 | 珠海冠宇电池股份有限公司 | Lithium ion battery with excellent high-temperature performance |
| CA3197434A1 (en) * | 2020-11-04 | 2022-05-12 | Stephen Laurence Glazier | Additive mixtures for non-aqueous battery electrolytes |
| CN113299973B (en) * | 2021-05-21 | 2023-01-31 | 珠海冠宇电池股份有限公司 | Lithium ion battery and application thereof |
| CN113161616A (en) * | 2021-06-07 | 2021-07-23 | 珠海冠宇电池股份有限公司 | Lithium ion battery |
| CN113839093A (en) * | 2021-09-16 | 2021-12-24 | 湖州昆仑亿恩科电池材料有限公司 | Non-aqueous electrolyte of lithium ion battery and application thereof |
| CN114039097B (en) * | 2021-11-29 | 2022-10-28 | 珠海冠宇电池股份有限公司 | Lithium ion battery |
| CN114267882A (en) * | 2021-12-17 | 2022-04-01 | 珠海冠宇电池股份有限公司 | Battery with a battery cell |
| CN117832626A (en) * | 2024-03-06 | 2024-04-05 | 宁德新能源科技有限公司 | Electrolyte, electrochemical device, and electronic apparatus |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1866605A (en) * | 2005-02-28 | 2006-11-22 | 三星Sdi株式会社 | Electrolyte for a lithium battery and lithium battery comprising the same |
| CN105098244A (en) * | 2015-08-06 | 2015-11-25 | 宁德新能源科技有限公司 | Electrolyte and lithium ion battery comprising same |
| CN106252716A (en) * | 2016-10-17 | 2016-12-21 | 东莞市凯欣电池材料有限公司 | A kind of safe lithium ion power battery electrolyte and lithium-ion-power cell |
-
2019
- 2019-10-29 CN CN201911039682.6A patent/CN110707361B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1866605A (en) * | 2005-02-28 | 2006-11-22 | 三星Sdi株式会社 | Electrolyte for a lithium battery and lithium battery comprising the same |
| CN105098244A (en) * | 2015-08-06 | 2015-11-25 | 宁德新能源科技有限公司 | Electrolyte and lithium ion battery comprising same |
| CN106252716A (en) * | 2016-10-17 | 2016-12-21 | 东莞市凯欣电池材料有限公司 | A kind of safe lithium ion power battery electrolyte and lithium-ion-power cell |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110707361A (en) | 2020-01-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110707361B (en) | Electrolyte for high-voltage soft-package lithium ion battery suitable for high-rate charge and discharge | |
| CN111628218B (en) | Lithium ion battery and preparation method thereof | |
| CN111640986B (en) | High-safety electrolyte suitable for high-energy-density lithium ion battery | |
| CN109728340B (en) | Lithium ion battery | |
| CN112271338B (en) | Electrolyte and lithium ion battery containing same | |
| CN112467209A (en) | High-voltage lithium ion battery with high and low temperature performance | |
| CN112151866B (en) | Electrolyte for lithium ion battery and lithium ion battery comprising same | |
| CN110994030B (en) | Lithium battery electrolyte and lithium ion battery | |
| CN109888384B (en) | Electrolyte and battery containing the same | |
| CN112531212A (en) | Non-aqueous electrolyte with high-temperature characteristic and low impedance, application thereof and lithium ion battery | |
| CN112117491A (en) | Electrolyte for lithium ion battery and lithium ion battery comprising same | |
| CN111129598A (en) | High-voltage lithium ion battery non-aqueous electrolyte and lithium ion battery thereof | |
| CN113991178A (en) | Non-aqueous electrolyte of lithium ion battery and application thereof | |
| CN113839095B (en) | Electrolyte and battery comprising same | |
| CN113809401B (en) | Nonaqueous electrolyte for lithium ion battery and application thereof | |
| CN111697267A (en) | Electrolyte solution, electrochemical device containing electrolyte solution, and electronic device | |
| CN112825371A (en) | Electrolyte for high-voltage lithium ion battery and lithium ion battery comprising same | |
| CN110783628A (en) | Non-aqueous electrolyte of lithium ion battery and lithium ion battery using same | |
| CN113013486A (en) | Electrolyte and lithium ion battery comprising same | |
| CN112531213A (en) | Non-aqueous electrolyte with high-temperature characteristics and normal-temperature cycle, application thereof and lithium ion battery | |
| CN113964385B (en) | Electrolyte, preparation method and application thereof | |
| US20220223915A1 (en) | Electrolyte, electrochemical device including same, and electronic device | |
| CN113889667B (en) | High-voltage electrolyte adaptive to lithium cobaltate battery capable of being charged quickly and application of high-voltage electrolyte | |
| CN112825369B (en) | High-voltage lithium ion battery with excellent high-temperature performance | |
| CN112467205B (en) | High-voltage non-aqueous electrolyte and lithium ion battery containing same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Address after: 519180 No. 209 Pearl Peak Avenue, Jingan Town, Doumen District, Zhuhai City, Guangdong Province Applicant after: Zhuhai Guanyu Battery Co., Ltd Address before: 519180 No. 209 Pearl Peak Avenue, Jingan Town, Doumen District, Zhuhai City, Guangdong Province Applicant before: ZHUHAI COSLIGHT BATTERY Co.,Ltd. |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |