CN109818064B - High-temperature high-voltage non-aqueous electrolyte and lithium ion battery containing same - Google Patents
High-temperature high-voltage non-aqueous electrolyte and lithium ion battery containing same Download PDFInfo
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Abstract
The invention relates to the technical field of lithium ion batteries, in particular to a high-temperature high-voltage non-aqueous electrolyte and a lithium ion battery containing the same. The high-temperature high-voltage non-aqueous electrolyte comprises a lithium salt, a non-aqueous solvent and an additive, wherein the additive comprises a first borate additive, a second nitrogen-containing lithium salt additive, a third silicon nitrogen-based additive and a fourth sulfonic acid ester and sulfuric acid ester mixed additive. After the additives are properly proportioned, the advantages of the additives can be exerted, the disadvantages of the additives can be mutually inhibited, the high-temperature storage performance of the battery is improved through the mutual synergistic effect of the additives, the high-temperature cycle performance of the battery is improved, and the application prospect of the additives under the conditions of high temperature and high voltage is good.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a high-temperature high-voltage non-aqueous electrolyte and a lithium ion battery containing the same.
Background
In lithium ion batteries, high-voltage ternary positive electrode materials are widely applied to portable electronic devices such as mobile phones and notebook computers, and electric vehicles and large energy storage devices due to the advantages of high energy density, environmental friendliness, long cycle life and the like, and the energy density requirement of the batteries is higher and higher, so that the commercial ternary positive electrode material lithium ion batteries (with working voltage of 4.2V) are difficult to meet the requirement.
At present, research shows that one of effective ways for improving the energy density of the ternary electrode material is to improve the working voltage of the battery, which is a trend of battery development and is also an inevitable requirement for new energy automobile development. However, after the working voltage of the ternary power battery is increased, the performances of the battery, such as charge and discharge cycles, are reduced. The reasons may be: on one hand, the anode material is not stable enough under high voltage, on the other hand, the matching property of the electrolyte and the material is poor, and the common electrolyte can be oxidized and decomposed under the condition of high voltage, so that the battery has poor high-temperature storage performance, poor high-temperature cycle performance, poor low-temperature discharge performance and poor safety.
The Chinese invention patent application (publication No. CN103579676A) proposes that a fluoro-solvent (FEC, TFPC and the like) is used for solving the problem that the electrolyte is not high-pressure resistant, but the fluoro-solvent is continuously reduced at a graphite cathode to generate HF, the HF reacts with the electrolyte to generate LiF to deposit on the graphite cathode, the thickness of an SEI film is increased, the charging and discharging performance is influenced, and meanwhile, the introduced solvent in the test processThe water content will also cause LiPF6HF is generated by decomposition, so that the thickness of an SEI film is continuously increased, and the phenomenon of gas generation occurs. Therefore, the development of lithium ion battery electrolyte suitable for high-voltage ternary material system is urgent.
Disclosure of Invention
The invention aims to overcome the defects of the background technology and provides a high-temperature high-voltage nonaqueous electrolyte and a lithium ion battery containing the same.
In order to achieve the purpose of the invention, the high-temperature high-voltage nonaqueous electrolytic solution comprises a lithium salt, a nonaqueous solvent and an additive, wherein the additive comprises a first borate additive, a second nitrogen-containing lithium salt additive, a third silazane additive and a fourth mixed sulfonate and sulfate additive, and the third silazane additive is represented by a general formula (1) or (2):
wherein R is1-R3Each independently represents C1-C61-2 hydrogen atoms of alkyl, vinyl, amino or amino groups by C1-C4Hydrocarbyl-substituted hydrocarbylamino; r4-R6Each independently represents C1-C61-2 hydrogen atoms of alkyl, vinyl, amino or amino groups by C1-C4Hydrocarbyl-substituted hydrocarbylamino; r7-R8Each independently represents a hydrogen atom or C1-C61-2 hydrogen atoms of alkyl, vinyl, amino or amino groups by C1-C4Substituted by hydrocarbon radicalsA hydrocarbylamino group, or a group having the structure (3);
in the structure (3), R9-R11Each independently represents C1-C61-2 hydrogen atoms of alkyl, phenyl, vinyl, amino or amino groups by C1-C4Hydrocarbyl-substituted hydrocarbylamino groups.
In the present invention, preferably, the first type of borate additive is selected from lithium difluorooxalato borate (LiDBOF), lithium dioxalate borate (LiBOB), lithium tetrafluoroborate (LiBF)4) Lithium bis (2-methyl-2-fluoromalonate) borate (LiBMFMB), dilithium dodecafluoroborate (Li)2B12F12) One or more of (a).
Preferably, the second type of lithium salt additive containing nitrogen is selected from one or more of lithium bis (fluorosulfonyl) imide (LiFSI), lithium bis (trifluoromethanesulfonyl) imide (LiTFSI), and lithium fluorosulfonyl (trifluoromethanesulfonyl) imide (LiFTFSI).
Preferably, the third type of silazane-based additive is selected from one or more of 1- (trimethylsilyl) imidazole (TMSI), 1- (triethylsilyl) imidazole, 1-dimethyl-1-ethylsilylimidazole, N-dimethylaminotrimethylsilane, N-diethylaminotrimethylsilane, 1, 3-dibutyl-1, 1,3, 3-tetramethyldisilazane.
More preferably, the first type of borate additive is lithium difluorooxalato borate (LiDBOF), the second type of nitrogen-containing lithium salt additive is lithium bis-fluorosulfonylimide (LiFSI), the third type of silazane-based additive is 1- (trimethylsilyl) imidazole (TMSI) or 1, 1-dimethyl-1-ethylsilazole, and the fourth type of mixed sulfonate and sulfate additive is a mixture of vinyl sulfate (DTD) and Propylene Sultone (PST).
Further preferably, the addition amount of the first type borate additive is 0.5-10%, for example 1%, of the total mass of the electrolyte; the addition amount of the second nitrogen-containing lithium salt additive is 0.1-5 percent, such as 1-3 percent of the total mass of the electrolyte; the addition amount of the third silicon-nitrogen-based additive is 0.01-0.7 percent of the total mass of the electrolyte, such as 0.1-0.5 percent; the addition amount of the sulfonate additive in the fourth type of sulfonate and sulfate mixed additive is 0.1-1% of the total mass of the electrolyte, and the addition amount of the sulfate additive is 1-2% of the total mass of the electrolyte.
Still more preferably, the additive comprises lithium difluoro oxalate borate accounting for 1 percent of the total mass of the electrolyte, lithium bis-fluoro sulfonyl imide accounting for 1 to 3 percent of the total mass of the electrolyte, 1- (trimethylsilyl) imidazole (TMSI) or 1, 1-dimethyl-1-ethylsilyl imidazole accounting for 0.1 to 0.5 percent of the total mass of the electrolyte, vinyl sulfate accounting for 1 to 2 percent of the total mass of the electrolyte and propylene sultone accounting for 0.5 percent of the total mass of the electrolyte.
Preferably, the lithium salt comprises lithium hexafluorophosphate (LiPF)6) And the addition amount thereof is 0.5 to 20%, for example, 12.5% of the total mass of the electrolyte.
In the present invention, the non-aqueous solvent is an organic carbonate solvent, preferably, the organic carbonate solvent is one or more selected from the group consisting of ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, and propyl methyl carbonate, and more preferably, the non-aqueous solvent comprises ethylene carbonate, ethyl methyl carbonate, and diethyl carbonate; more preferably, the ethylene carbonate, the ethyl methyl carbonate and the diethyl carbonate are uniformly mixed in a mass ratio of 1:1: 1.
The invention also provides a lithium ion battery matched with the electrolyte, which comprises a positive pole piece, a negative pole piece and the high-temperature high-voltage non-aqueous electrolyte, wherein the positive pole piece comprises a positive current collector and a positive diaphragm on the surface of the positive current collector, and the negative pole piece comprises a negative current collector and a negative diaphragm on the surface of the negative current collector; the anode diaphragm comprises an anode active material, a conductive agent and a binder, and the cathode diaphragm comprises a cathode active material, a conductive agent and a binder; the positive active material is LiNi1-x-y-zCoxMnyAlzO2Wherein: x is more than or equal to 0 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 1, z is more than or equal to 0 and less than or equal to 1, and x + y + z is more than or equal to 0 and less than or equal to 1; the above-mentionedThe negative active material is nano silicon or SiOxAnd the silicon-carbon negative electrode material is compounded with graphite.
Preferably, the positive electrode active material is at least one of ternary system NCM622, NCM811, and NCA, and the negative electrode active material is artificial graphite.
Compared with the prior art, the high-temperature high-voltage non-aqueous electrolyte and the lithium ion battery containing the non-aqueous electrolyte have the following advantages:
(1) in the non-aqueous electrolyte, the first borate additive is added, so that an SEI film with good ionic conductivity can be formed on the positive electrode and the negative electrode, and the cycle performance and the high-temperature storage performance of the battery are improved; the second nitrogen-containing lithium salt additive is added, so that the cycle performance of the battery under high voltage can be improved; the third silicon-nitrogen-based additive is added, so that the high-low temperature performance of the battery can be effectively improved, the additive can inhibit the decomposition of LiPF6, a small amount of decomposition products form a good SEI film on the surface of graphite through electrostatic interaction, the cycle performance is improved, and gas generation is inhibited;
(2) according to the invention, after the silicon nitrogen-based additive, the solvent, the lithium salt, the nitrogen lithium salt additive, the borate, the sulfonate and the sulfate mixed additive are properly proportioned, the advantages of the silicon nitrogen-based additive and the solvent can be exerted, the defects of the silicon nitrogen-based additive and the solvent can be mutually inhibited, and the electrolyte has a good application prospect under the conditions of high temperature and high voltage through the mutual synergistic effect of the silicon nitrogen-based additive, the lithium salt additive, the borate, the sulfonate and the sulfate.
(3) In the electrolyte, the characteristic of Si-N bond in the additive 1- (trimethylsilyl) imidazole effectively removes the water in the electrolyte and inhibits LiFP6The decomposition of the electrolyte is carried out, the resistance of the decomposition product is reduced on the surface of the graphite through the electrostatic action, and the formed SEI film has good ionic conductivity, so that the high-temperature storage performance of the battery is improved, and the high-temperature cycle performance of the battery is improved.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. It is to be understood that the following description is only illustrative of the present invention and is not to be construed as limiting the present invention.
As used herein, the terms "comprises," "comprising," "includes," "including," "contains," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.
When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.
The indefinite articles "a" and "an" preceding an element or component of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be read to include one or at least one, and the singular form of an element or component also includes the plural unless the number clearly indicates the singular.
Further, the technical features of the embodiments of the present invention may be combined with each other as long as they do not conflict with each other.
Example 1
In a glove box filled with argon, the oxygen content of which is less than or equal to 1ppm and the water content of which is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, and the electrolyte is added into the mixed liquid1- (trimethylsilyl) imidazole (TMSI) with the mass of 0.1 percent, vinyl sulfate (DTD) with the mass of 1 percent of the total mass of the electrolyte, 1, 3-Propylene Sultone (PST) with the mass of 0.5 percent of the total mass of the electrolyte, and then lithium hexafluorophosphate (LiPF) with the mass of 12.5 percent of the total mass of the electrolyte are respectively added into the mixed solution6) And lithium bis (fluorosulfonyl) imide (LiFSI) in an amount of 1% by mass of the total electrolyte solution, and lithium difluoro (oxalato) borate (liddob) in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved, thereby obtaining an electrolyte solution of example 1.
And injecting the prepared electrolyte solution into a soft package lithium ion battery with NCM622 as a positive electrode material and a graphite negative electrode as a negative electrode, and carrying out processes of packaging, laying aside, formation, aging, secondary packaging, capacity grading and the like after the injection is finished to obtain the NCM 622/graphite battery.
Example 2
In a glove box filled with argon, the oxygen content of which is less than or equal to 1ppm and the water content of which is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, TMSI (tetramethylammonium sulfate) accounting for 0.2 percent of the total mass of the electrolyte, DTD (dimethyltin bromide) accounting for 1 percent of the total mass of the electrolyte and PST (lithium phosphate) accounting for 0.5 percent of the total mass of the electrolyte are added into the mixed solution, and LiPF (lithium iron phosphate) accounting for 12.5 percent of the total mass of the electrolyte6A lithium ion battery was prepared in the same manner as in example 1, except that LiFSI in an amount of 1% by mass of the total electrolyte solution and liddob in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved.
Example 3
In a glove box filled with argon, the oxygen content of which is less than or equal to 1ppm and the water content of which is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, TMSI (tetramethylammonium sulfate) accounting for 0.5 percent of the total mass of the electrolyte, DTD (dimethyltin bromide) accounting for 1 percent of the total mass of the electrolyte and PST (lithium phosphate) accounting for 0.5 percent of the total mass of the electrolyte are added into the mixed solution, and LiPF (lithium iron phosphate) accounting for 12.5 percent of the total mass of the electrolyte6A lithium ion battery was prepared in the same manner as in example 1, except that LiFSI in an amount of 1% by mass of the total electrolyte solution and liddob in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved.
Example 4
Filled with argon and having an oxygen content of less than or equal to 1ppm and a water content of less than or equal to 1ppmIn the glove box, ethylene carbonate, ethyl methyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, TMSI (tetramethylbenzidine) with the total mass of 0.7 percent of electrolyte, DTD (diethylenetriamine pentaacetic acid) with the total mass of 1 percent of electrolyte and PST (phospho-succinic acid) with the total mass of 1 percent of electrolyte are added into the mixed solution, and LiPF (lithium ion PF) with the total mass of 12.5 percent of electrolyte is added into the mixed solution respectively6A lithium ion battery was prepared in the same manner as in example 1, except that LiFSI in an amount of 1% by mass of the total electrolyte solution and liddob in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved.
Example 5
In a glove box filled with argon, the oxygen content of which is less than or equal to 1ppm and the water content of which is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, TMSI (tetramethylammonium sulfate) accounting for 0.3 percent of the total mass of the electrolyte, DTD (dimethyltin bromide) accounting for 1 percent of the total mass of the electrolyte and PST (lithium phosphate) accounting for 0.5 percent of the total mass of the electrolyte are added into the mixed solution, and LiPF (lithium iron phosphate) accounting for 12.5 percent of the total mass of the electrolyte6A lithium ion battery was prepared in the same manner as in example 1, except that LiFSI in an amount of 2% by mass of the total electrolyte solution and liddob in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved.
Example 6
In a glove box filled with argon, the oxygen content of which is less than or equal to 1ppm and the water content of which is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, TMSI (tetramethylammonium sulfate) accounting for 0.3 percent of the total mass of the electrolyte, DTD (dimethyltin bromide) accounting for 1 percent of the total mass of the electrolyte and PST (lithium phosphate) accounting for 0.5 percent of the total mass of the electrolyte are added into the mixed solution, and LiPF (lithium iron phosphate) accounting for 12.5 percent of the total mass of the electrolyte6A lithium ion battery was prepared in the same manner as in example 1, except that LiFSI in an amount of 3% by mass of the total electrolyte solution and liddob in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved.
Example 7
In a glove box filled with argon, the oxygen content is less than or equal to 1ppm, the water content is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, 1-dimethyl-1-ethyl silicon-based imidazole of which the total mass is 0.3 percent of the total mass of electrolyte, DTD of which the total mass is 1 percent of the total mass of electrolyte and electricity are added into the mixed solutionPST accounting for 0.5 percent of the total mass of the electrolyte, and LiPF accounting for 12.5 percent of the total mass of the electrolyte are respectively added into the mixed solution6A lithium ion battery was prepared in the same manner as in example 1, except that LiFSI in an amount of 1% by mass of the total electrolyte solution and liddob in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved.
Example 8
In a glove box filled with argon, the oxygen content of which is less than or equal to 1ppm and the water content of which is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, 1-dimethyl-1-ethyl silicon-based imidazole accounting for 0.3 percent of the total mass of the electrolyte, DTD accounting for 2 percent of the total mass of the electrolyte and PST accounting for 0.1 percent of the total mass of the electrolyte are added into the mixed solution, and LiPF accounting for 12.5 percent of the total mass of the electrolyte is added into the mixed solution respectively6A lithium ion battery was prepared in the same manner as in example 1, except that LiFSI in an amount of 1% by mass of the total electrolyte solution and liddob in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved.
Example 9
In a glove box filled with argon, the oxygen content is less than or equal to 1ppm, the water content is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, N-dimethyl amino trimethyl silane accounting for 0.3 percent of the total mass of the electrolyte, DTD accounting for 1 percent of the total mass of the electrolyte and PST accounting for 0.5 percent of the total mass of the electrolyte are added into the mixed solution, and LiPF accounting for 12.5 percent of the total mass of the electrolyte is added into the mixed solution respectively6A lithium ion battery was prepared in the same manner as in example 1, except that LiFSI in an amount of 1% by mass of the total electrolyte solution and liddob in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved.
Example 10
In a glove box filled with argon, the oxygen content of which is less than or equal to 1ppm and the water content of which is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, TMSI (tetramethylammonium sulfate) accounting for 0.3 percent of the total mass of the electrolyte, DTD (dimethyltin bromide) accounting for 1 percent of the total mass of the electrolyte and PST (lithium phosphate) accounting for 0.5 percent of the total mass of the electrolyte are added into the mixed solution, and LiPF (lithium iron phosphate) accounting for 12.5 percent of the total mass of the electrolyte6LiFSI accounting for 7% of the total mass of the electrolyte and 10% of the total mass of the electrolyte% of LiDFOB was dissolved completely by stirring, and a lithium ion battery was prepared in the same manner as in example 1.
Example 11
In a glove box filled with argon, the oxygen content of which is less than or equal to 1ppm and the water content of which is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, TMSI (tetramethylammonium sulfate) accounting for 0.3 percent of the total mass of the electrolyte, DTD (sodium dodecyl sulfate) accounting for 1 percent of the total mass of the electrolyte and PST (lithium phosphate) accounting for 5 percent of the total mass of the electrolyte are added into the mixed solution, and LiPF (lithium ionic phosphate) accounting for 12.5 percent of the total mass of the electrolyte6A lithium ion battery was prepared in the same manner as in example 1, except that LiFSI in an amount of 1% by mass of the total electrolyte solution and liddob in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved.
Comparative example 1
In a glove box filled with argon, the oxygen content of which is less than or equal to 1ppm and the water content of which is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, and LiPF accounting for 12.5 percent of the total mass of the electrolyte is respectively added into the mixed solution6And LiDFOB in an amount of 1% by mass based on the total mass of the electrolyte solution, and stirred to be completely dissolved, thereby obtaining the electrolyte solution of comparative example 1.
And injecting the prepared electrolyte solution into a soft package lithium ion battery with NCM622 as a positive electrode material and a graphite negative electrode as a negative electrode, and carrying out processes of packaging, laying aside, formation, aging, secondary packaging, capacity grading and the like after the injection is finished to obtain the NCM 622/graphite battery.
Comparative example 2
In a glove box filled with argon, the oxygen content is less than or equal to 1ppm, the water content is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, and LiPF accounting for 12.5 percent of the total mass of the electrolyte is added into the mixed solution respectively6And LiDFOB in an amount of 3% by mass based on the total mass of the electrolyte solution were stirred to be completely dissolved, and a lithium ion battery was prepared in the same manner as in comparative example 1.
Comparative example 3
In a glove box which is filled with argon and has the oxygen content less than or equal to 1ppm and the water content less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate,Diethyl carbonate is uniformly mixed according to the mass ratio of 1:1:1, and LiPF accounting for 12.5 percent of the total mass of the electrolyte is added into the mixed solution respectively6And LiDFOB in an amount of 15% by mass based on the total mass of the electrolyte solution were stirred to be completely dissolved, and a lithium ion battery was prepared in the same manner as in comparative example 1.
Comparative example 4
In a glove box filled with argon, the oxygen content is less than or equal to 1ppm, the water content is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, and LiPF accounting for 12.5 percent of the total mass of the electrolyte is added into the mixed solution respectively6And LiFSI in an amount of 1% by mass of the total electrolyte solution were stirred to be completely dissolved, and a lithium ion battery was prepared in the same manner as in comparative example 1.
Comparative example 5
In a glove box filled with argon, the oxygen content is less than or equal to 1ppm, the water content is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, and LiPF accounting for 12.5 percent of the total mass of the electrolyte is added into the mixed solution respectively6And LiFSI in an amount of 10% by mass of the total electrolyte solution were stirred to be completely dissolved, and a lithium ion battery was prepared in the same manner as in comparative example 1.
Comparative example 6
In a glove box filled with argon, the oxygen content is less than or equal to 1ppm, the water content is less than or equal to 1ppm, ethylene carbonate, methyl ethyl carbonate and diethyl carbonate are uniformly mixed according to the mass ratio of 1:1:1, DTD accounting for 0.5 percent of the total mass of the electrolyte is added into the mixed solution, and LiPF accounting for 12.5 percent of the total mass of the electrolyte is added into the mixed solution respectively6A lithium ion battery was prepared in the same manner as in comparative example 1, except that the lithium ion battery was completely dissolved by stirring.
Electrochemical performance test
(1) And (3) testing the normal-temperature cycle performance: at 25 ℃, the formed lithium ion battery is charged to 4.35V according to a constant current and a constant voltage of 1C, the current is cut off to 0.02C, and then the lithium ion battery is discharged to 3.0V according to a constant current of 1C. The capacity retention ratio at 500 cycles after 500 cycles of charge/discharge (abbreviated as 25 ℃ capacity% in Table 1) was calculated. The calculation formula is as follows:
the 500-week capacity retention rate is 500-week cycle discharge capacity/first-week cycle discharge capacity × 100%.
(2) High temperature storage performance at 60 ℃: charging and discharging the battery once at room temperature according to 0.5C, stopping current at 0.02C, recording initial capacity, fully charging the battery at constant current and constant voltage according to 0.5C, testing the initial thickness of the battery, and testing the internal resistance and voltage of the battery by using an internal resistance tester; storing the fully charged battery in a constant temperature environment of 60 ℃ for 7 days, testing the thermal thickness of the battery, and calculating the thermal state expansion (which is abbreviated as thermal thickness percent in table 1); after the battery is cooled to the normal temperature for 6 hours, testing the cold thickness, testing the internal resistance of the battery by using an internal resistance tester, recording data and calculating the internal resistance change rate (referred to as the internal resistance in the table 1 for short), after the test is finished, discharging to 3.0V at 0.5C, and recording the residual capacity of the battery; the maximum capacity, namely, the battery recovery capacity, was recorded for 3 cycles after 3 charge/discharge cycles at 0.5C, and the battery capacity remaining ratio (% remaining in table 1) and the battery capacity recovery ratio (% recovery in table 1) were calculated. The calculation formula is as follows:
the thermal state expansion ratio (% of the battery) — (thermal thickness-initial thickness)/initial thickness × 100%;
the change rate (% of the internal resistance of the battery) (internal resistance after storage-initial internal resistance)/initial internal resistance × 100%;
remaining battery capacity (%) is retention capacity/initial capacity × 100%;
the battery capacity recovery rate (%) is the recovery capacity/initial capacity × 100%.
(3)60 ℃ cycle performance test: and (3) placing the formed lithium ion battery in an environment of 60 ℃ to be charged to 4.35V according to a constant current and a constant voltage of 1C, stopping the current to be 0.02C, and then discharging to 3.0V according to a constant current of 1C. The capacity retention ratio at 500 cycles after 500 cycles of charge/discharge (abbreviated as 60 ℃ capacity% in Table 1) was calculated. The calculation formula is as follows:
the 500-week capacity retention rate is 500-week cycle discharge capacity/first-week cycle discharge capacity × 100%.
TABLE 1 Battery Performance test results
The experimental results of table 1 show that: in a LiFSI + DTD + LiDFOB + PST system, a silazane group is added to form a stable SEI film on a graphite cathode, and Si-N bonds in the additive can effectively inhibit a trace amount of water in the electrolyte from reacting on LiPF6The decomposition product reduces the impedance on the surface of the graphite through electrostatic action, improves the cycle performance and high-temperature storage performance of the battery, and improves the high-temperature cycle performance.
A comparison of the experimental results of comparative examples 1-6 and examples in Table 1 shows that: in the electrolyte, after the silicon nitrogen-based additive, the solvent, the lithium salt, the nitrogen lithium salt additive, the borate, the sulfonate and the sulfate mixed additive are properly proportioned, the advantages of the silicon nitrogen-based additive and the solvent can be exerted, the defects of the silicon nitrogen-based additive and the lithium salt additive can be mutually inhibited, and the electrolyte has a good application prospect under the conditions of high temperature and high voltage through the mutual synergistic effect of the silicon nitrogen-based additive, the lithium salt additive, the borate, the sulfonate and the sulfate.
It will be understood by those skilled in the art that the foregoing is only exemplary of the present invention and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (9)
1. The high-temperature high-voltage non-aqueous electrolyte is characterized by consisting of lithium hexafluorophosphate, a non-aqueous solvent and an additive, wherein the additive consists of a first borate additive, a second nitrogen-containing lithium salt additive, a third silazane-based additive and a fourth mixed sulfonate and sulfate additive, and the third silazane-based additive is represented by a general formula (1) or (2):
wherein R is1-R3Each independently represents C1-C61-2 hydrogen atoms of alkyl, vinyl, amino or amino groups by C1-C4Hydrocarbyl-substituted hydrocarbylamino; r4-R6Each independently represents C1-C61-2 hydrogen atoms of alkyl, vinyl, amino or amino groups by C1-C4Hydrocarbyl-substituted hydrocarbylamino; r7-R8Each independently represents a hydrogen atom or C1-C61-2 hydrogen atoms of alkyl, vinyl, amino or amino groups by C1-C4A hydrocarbyl-substituted hydrocarbylamino group, or a group having the structure (3);
in the structure (3), R9-R11Each independently represents C1-C61-2 hydrogen atoms of alkyl, phenyl, vinyl, amino or amino groups by C1-C4Hydrocarbyl-substituted hydrocarbylamino;
the first borate additive is lithium difluoro oxalate borate, the second nitrogen-containing lithium salt additive is lithium bis (fluorosulfonyl) imide, the third silicon nitrogen-based additive is 1- (trimethylsilyl) imidazole or 1, 1-dimethyl-1-ethylsilyl imidazole, and the fourth sulfonate and sulfate mixed additive is a mixture of vinyl sulfate and propylene sultone; the addition amount of the first borate additive is 0.5-10% of the total mass of the electrolyte; the addition amount of the second nitrogen-containing lithium salt additive is 0.1-5% of the total mass of the electrolyte; the addition amount of the third silicon-nitrogen-based additive is 0.1-0.5% of the total mass of the electrolyte; the addition amount of the sulfonate additive in the fourth type of sulfonate and sulfate mixed additive is 0.1-1% of the total mass of the electrolyte, and the addition amount of the sulfate additive is 1-2% of the total mass of the electrolyte.
2. The high-temperature high-voltage nonaqueous electrolytic solution according to claim 1, wherein the amount of the lithium hexafluorophosphate added is 0.5 to 20% by mass based on the total mass of the electrolytic solution.
3. The high-temperature high-voltage nonaqueous electrolytic solution according to claim 2, wherein the amount of lithium hexafluorophosphate added is 12.5% by mass of the total mass of the electrolytic solution.
4. The high-temperature high-voltage nonaqueous electrolytic solution according to claim 1, wherein the nonaqueous solvent is an organic carbonate solvent.
5. The high-temperature high-voltage nonaqueous electrolytic solution of claim 4, wherein the organic carbonate-based solvent is one or more selected from ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, ethylmethyl carbonate, and propylmethyl carbonate.
6. The high-temperature high-voltage nonaqueous electrolytic solution according to claim 5, wherein the nonaqueous solvent contains ethylene carbonate, ethylmethyl carbonate, and diethyl carbonate.
7. The high-temperature high-voltage nonaqueous electrolytic solution according to claim 6, wherein the ethylene carbonate, the ethyl methyl carbonate, and the diethyl carbonate are uniformly mixed in a mass ratio of 1:1: 1.
8. A lithium ion battery comprising a positive electrode tab, a negative electrode tab and the method of claim1-7, wherein the positive pole piece comprises a positive current collector and a positive membrane on the surface of the positive current collector, and the negative pole piece comprises a negative current collector and a negative membrane on the surface of the negative current collector; the anode diaphragm comprises an anode active material, a conductive agent and a binder, and the cathode diaphragm comprises a cathode active material, a conductive agent and a binder; the positive active material is LiNi1-x-y-zCoxMnyAlzO2Wherein: x is more than or equal to 0 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 1, z is more than or equal to 0 and less than or equal to 1, and x + y + z is more than or equal to 0 and less than or equal to 1; the negative active material is nano silicon or SiOxAnd the silicon-carbon negative electrode material is compounded with graphite.
9. The lithium ion battery according to claim 8, wherein the positive electrode active material is at least one of ternary systems NCM622, NCM811, and NCA, and the negative electrode active material is artificial graphite.
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| CN110994025A (en) * | 2019-12-10 | 2020-04-10 | 惠州市豪鹏科技有限公司 | Electrolyte additive, electrolyte and lithium ion battery |
| CN111525192A (en) * | 2020-05-06 | 2020-08-11 | 东莞市杉杉电池材料有限公司 | Lithium ion battery non-aqueous electrolyte and lithium ion battery |
| CN111628219A (en) * | 2020-06-05 | 2020-09-04 | 宁德新能源科技有限公司 | Electrolyte solution, electrochemical device containing electrolyte solution, and electronic device |
| KR20210155370A (en) * | 2020-06-15 | 2021-12-22 | 주식회사 엘지에너지솔루션 | Electrolyte additive for secondary battery, non-aqueous electrolyte for lithium secondary battery comprising the same and lithium secondary battery |
| CN113823835A (en) * | 2020-06-18 | 2021-12-21 | 广州汽车集团股份有限公司 | Lithium secondary battery electrolyte, lithium secondary battery cell, lithium secondary battery pack and application thereof |
| CN111883838B (en) * | 2020-08-03 | 2023-05-12 | 香河昆仑新能源材料股份有限公司 | Nonaqueous electrolyte and lithium ion battery |
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| CN114447427B (en) * | 2020-10-30 | 2024-04-05 | 张家港市国泰华荣化工新材料有限公司 | Nonaqueous electrolyte and lithium battery |
| CN114597492A (en) * | 2021-04-12 | 2022-06-07 | 深圳市研一新材料有限责任公司 | Nonaqueous electrolyte solution and lithium ion battery using same |
| CN113394457B (en) * | 2021-06-15 | 2023-02-24 | 杉杉新材料（衢州）有限公司 | Lithium ion battery electrolyte and lithium ion battery |
| CN113964385B (en) * | 2021-10-19 | 2024-01-26 | 远景动力技术(江苏)有限公司 | Electrolyte, preparation method and application thereof |
| CN114156526A (en) * | 2021-12-02 | 2022-03-08 | 浙江大学 | High-voltage electrolyte for lithium battery |
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| CN103401019B (en) * | 2013-08-08 | 2016-03-16 | 东莞市杉杉电池材料有限公司 | Silazane additive and apply its lithium-ion battery electrolytes preventing box hat from corroding prepared |
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