CN115411368B - Electrolyte and lithium-ion battery - Google Patents
Electrolyte and lithium-ion batteryInfo
- Publication number
- CN115411368B CN115411368B CN202211273118.2A CN202211273118A CN115411368B CN 115411368 B CN115411368 B CN 115411368B CN 202211273118 A CN202211273118 A CN 202211273118A CN 115411368 B CN115411368 B CN 115411368B
- Authority
- CN
- China
- Prior art keywords
- electrolyte
- lithium
- mass
- lithium salt
- carbonate
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Secondary Cells (AREA)
Abstract
本发明涉及锂离子电池技术领域，具体涉及一种电解液和锂离子电池，该锂离子电池电解液具有式I所示结构的化合物，式I所示结构的化合物为异硫氰酸苯酯类化合物。本发明利用电解液中异硫氰酸苯酯类化合物，能够提高电极/电解液界面的结构稳定性，并且能改善电池高温存储产气性能。The present invention relates to the technical field of lithium-ion batteries, and more particularly to an electrolyte and a lithium-ion battery. The electrolyte of the lithium-ion battery comprises a compound having the structure represented by Formula I, wherein the compound having the structure represented by Formula I is a phenyl isothiocyanate compound. The present invention utilizes the phenyl isothiocyanate compound in the electrolyte to enhance the structural stability of the electrode/electrolyte interface and improve the battery's high-temperature storage gas production performance.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to an electrolyte and a lithium ion battery.
Background
In order to solve the mileage anxiety and charging anxiety of electric automobile consumers, the subsequent development of lithium ion batteries needs to be guided by research with high energy density, high power, high safety and long service life. Ternary layered metal oxide cathode materials and silicon-carbon anode materials are receiving great attention due to their high theoretical specific capacities, but challenges remain during practical use. For example, lithium ion batteries have defects of poor structural stability of electrode/electrolyte interfaces, serious gas production caused by high-temperature storage of the batteries due to side reactions and the like.
How to improve the structural stability of the electrode/electrolyte interface and inhibit side reactions to realize a safe and reliable battery is a problem that needs to be solved by researchers in the field.
Disclosure of Invention
Therefore, the technical problem to be solved by the invention is to overcome the defects of the lithium ion battery in the prior art that the electrode/electrolyte interface has poor structural stability and is easy to generate side reaction, so that the battery stores gas at high temperature and the gas is serious, thereby providing the electrolyte and the lithium ion battery.
To this end, the invention provides an electrolyte comprising an organic solvent, a lithium salt and a compound having the structure of formula I:
Wherein R 1-R5 is independently selected from a hydrogen atom, a halogen, a cyano group, an isothiocyanate group, a substituted or unsubstituted alkyl group of C 1–C10, a substituted or unsubstituted alkoxy group of C 1–C10, a substituted or unsubstituted alkylthio group of C 1–C3, a substituted or unsubstituted aryloxy group of C 6-C10, or a substituted or unsubstituted ester group of C 1-C5, and R 1-R5 is not both hydrogen;
wherein when substituted, the substituent is selected from at least one of alkyl, alkoxy, alkylthio, halogen, isothiocyanate.
The term "1 to 3 hydrogen atoms are substituted with at least one selected from the group consisting of halogen and isothiocyanate groups" means that 1 to 3 hydrogen atoms may be substituted with only halogen, only isothiocyanate groups, or both halogen and isothiocyanate groups.
Further, R 1-R5 is independently selected from a hydrogen atom, a fluorine atom, a cyano group, an isothiocyanate group, an alkyl group of C 1–C10 which is unsubstituted or substituted with 1 to 3 fluorine atoms or with phenyl isothiocyanate, an alkoxy group of C 1–C10 which is unsubstituted or substituted with 1 to 3 fluorine atoms, an alkylthio group of C 1–C3 which is unsubstituted or substituted with 1 to 2 isothiocyanate groups, a phenoxy group or an ester group of C 1-C5 which is unsubstituted, and R 1-R5 is not simultaneously hydrogen.
Further, R 1-R5 is independently selected from the group consisting of a hydrogen atom, a fluorine atom, a cyano group, an isothiocyanate group, a methyl group, an ethyl group, an n-decyl group, -CF 3、-OCH3、-OCH2CH3、-SCH3、-SCF3、-COOCH3, a,Or alternatively
Preferably, the compound having the structure shown in formula I is selected from at least one of the compounds having the structure shown below:
further, the mass of the compound having the structure shown in formula I accounts for 0.1% -6.0% of the total mass of the electrolyte, and is preferably 0.2% -1.0%.
Further, the organic solvent comprises chain ester and cyclic ester, the mass of the chain ester accounts for 30-80% of the total mass of the electrolyte, the mass of the cyclic ester accounts for 15-50% of the total mass of the electrolyte, and the mass ratio of the chain ester to the cyclic ester is (5-9): 2-4.
Further, the chain ester comprises one or more of dimethyl carbonate (DMC), methyl ethyl carbonate (EMC), diethyl carbonate (DEC), methyl Propyl Carbonate (MPC), diphenyl carbonate (DPhC), ethyl Acetate (EA), propyl Acetate (PA), methyl Propionate (MP), ethyl Propionate (EP), propyl Propionate (PP), methyl Butyrate (MB) and Ethyl Butyrate (EB), and the cyclic ester comprises one or more of Ethylene Carbonate (EC), propylene Carbonate (PC), butylene Carbonate (BC), fluoroethylene carbonate (FEC) and gamma-butyrolactone (gamma-GBL).
Further, the lithium salts include lithium hexafluorophosphate (LiPF 6) and a second lithium salt, the second lithium salt including one or more of lithium tetrafluoroborate (LiBF 4), lithium bis (LiBOB) oxalate, lithium difluoro (LiDFOB) oxalate, lithium difluoro (LiDFOP) oxalate, lithium bis (fluorosulfonyl) imide (LiPSI) and lithium bis (trifluoromethylsulfonyl) imide (LiTFSI).
Further, the mass of LiPF 6 is 12-15% of the total mass of the electrolyte, the mass of the second lithium salt is 0-10% of the total mass of the electrolyte, liPF 6 is 80-100% of the total mass of LiPF 6 and the second lithium salt, and the second lithium salt is 0-15% of the total mass of LiPF 6 and the second lithium salt.
The invention also provides a preparation method of the electrolyte, which comprises the following steps:
Adding lithium salt into organic solvent, mixing compound with structure shown in formula I into the mixed solution to obtain electrolyte, and further mixing lithium salt and organic solvent at temperature not higher than 2deg.C.
Since the electrolyte temperature increases due to heat release when the lithium salt is added, and the lithium salt is decomposed to some extent by heat, it is necessary to control the temperature at a low temperature when the lithium salt is mixed with the solvent.
In another aspect of the invention, a lithium ion battery using the above electrolyte is provided.
Further, the lithium ion battery also comprises a positive electrode active material, a negative electrode active material and the electrolyte.
Further, the positive electrode active material chemical formula includes LiaNi xCoyMnzO2, wherein a is more than or equal to 0.9 and less than or equal to 1.1,0.6 and less than or equal to x is more than or equal to 0.8,0.1 and less than or equal to 0.2,0.1 and less than or equal to z is more than or equal to 0.2, and x+y+z=1.
Further, the negative electrode active material includes one or more of silicon, silicon carbon, silicon oxygen, and silicon metal compounds.
The technical scheme of the invention has the following advantages:
1. Compared with the case that R 1-R5 is hydrogen at the same time, the hydrogen atom in the phenyl isothiocyanate compound is replaced by halogen, cyano, isothiocyanate, substituted or unsubstituted alkyl of C 1–C10, substituted or unsubstituted alkoxy of C 1–C10, substituted or unsubstituted alkylthio of C 1–C3, substituted or unsubstituted aryloxy of C 6-C10 or substituted or unsubstituted ester of C 1-C5, so that the stability of the passivation layer can be improved.
The electrolyte containing the compound with the structure shown in the formula I has thin and uniform passivation films formed on the positive electrode and the negative electrode, decomposition products (Li 2SO3,Li2 S and ROSO 2 Li) are stable, continuous decomposition of electrolyte solvents can be effectively inhibited, meanwhile, the interface impedance of the formed electrode/electrolyte is low, the conduction of Li + is facilitated, secondly, the compound with the structure shown in the formula I can react with trace water in the electrolyte to avoid corrosion of the interfaces of the positive electrode and the negative electrode due to generation of HF, thereby inhibiting dissolution and irreversible phase transition of positive transition metal ions and particle breakage of silicon-carbon negative electrodes so as to realize stable circulation of the battery, thirdly, side reaction of the electrolyte solvents on the interface is effectively inhibited under the cooperation of the stable interface and the water absorption effect, so that the gas production risk of the battery is improved, and the high-temperature volume expansion rate is reduced.
Wherein R 1-R5 is selected from halogen (preferably fluorine atom), or alkyl, alkoxy, alkylthio, aryloxy, or ester group containing halogen (preferably fluorine atom), which can further improve interface energy in the passivation layer, and alkoxy, ester group and cyano can form long chain organic polymer to increase mechanical properties of passivation layer, and thioether group can improve sulfur compound content in passivation layer, and better improve passivation layer stability.
2. According to the electrolyte provided by the invention, the mass of the compound with the structure shown in the formula I accounts for 0.1% -6.0% (preferably 0.2% -1.0%) of the total mass of the electrolyte, and if the content of the compound with the structure shown in the formula I in the electrolyte is insufficient, a firm interface passivation layer can not be formed and trace water in the electrolyte can not be effectively absorbed, so that the action effect of the compound is affected. If too much electrolyte possibly causes too thick passivation layer, thereby causing too large diffusion resistance of Li + to increase polarization, the mass of the compound with the structure shown in the formula I is controlled to be 0.1% -6.0% (preferably 0.2% -1.0%) of the total mass of the electrolyte, and the diffusion resistance of Li + can be reduced on the basis of ensuring the stability of the interface passivation layer, so that the cycle performance of the battery is better improved, and the gas production during high-temperature storage is reduced.
3. The electrolyte provided by the invention comprises LiPF 6 and one or more of other lithium salts such as LiBF 4, liBOB, liDFOB, liDFOP, liFSI and LiTFSI. The LiPF 6 has moderate ion migration number, moderate dissociation constant, good oxidation resistance and good aluminum foil passivation capability in common organic solvents, can be matched with various anode and cathode materials, and is the most main lithium salt in a lithium ion battery.
By controlling the mass of LiPF 6 to be 12-15% of the total mass of the electrolyte, the conductivity of the electrolyte can be improved and a suitable viscosity can be obtained. The other lithium salts are used as auxiliary lithium salts, so that the stability of the electrolyte and the migration number of lithium ions can be further improved.
4. The preparation method of the electrolyte provided by the invention is simple and reliable, and the lithium salt and the organic solvent are mixed under the condition that the temperature rise is not more than 2 ℃, so that the condition that the lithium salt is heated and decomposed due to the temperature rise of the electrolyte caused by the heat release of the lithium salt can be improved.
Detailed Description
The following examples are provided for a better understanding of the present invention and are not limited to the preferred embodiments described herein, but are not intended to limit the scope of the invention, any product which is the same or similar to the present invention, whether in light of the present teachings or in combination with other prior art features, falls within the scope of the present invention.
The application relates to the technical field of lithium ion batteries, in particular to an electrolyte and a lithium ion battery. The electrolyte comprises an organic solvent, lithium salt and a compound with a structure shown in a formula I. The application researches that the electrolyte using the compound with the structure shown in the formula I can form a thin and uniform passivation film on the positive electrode and the negative electrode, and the decomposition products (Li 2SO3,Li2 S and ROSO 2 Li) are stable, so that the continuous decomposition of the electrolyte solvent can be effectively inhibited, meanwhile, the interface impedance of the formed electrode/electrolyte is low, the conduction of Li + is facilitated, the compound with the structure shown in the formula I can react with trace water in the electrolyte, the generation of HF (hydrogen fluoride) is avoided to corrode the interface of the positive electrode and the negative electrode, thereby inhibiting the dissolution and irreversible phase transition of positive electrode transition metal ions and the particle breakage of silicon carbon negative electrode, and realizing the stable circulation of the battery.
In some embodiments of the present invention, a compound having a structure represented by formula I in a lithium ion electrolyte of the present invention
Wherein, R 1-R5 is independently selected from a hydrogen atom, a halogen, a cyano group, an isothiocyanate group, a substituted or unsubstituted alkyl group of C 1–C10, a substituted or unsubstituted alkoxy group of C 1–C10, a substituted or unsubstituted alkylthio group of C 1–C3, a substituted or unsubstituted aryloxy group of C 6-C10, or a substituted or unsubstituted ester group of C 1-C5, and R 1-R5 is not hydrogen at the same time;
wherein when substituted, the substituent is selected from at least one of alkyl, alkoxy, alkylthio, halogen and isothiocyanate.
The term "1 to 3 hydrogen atoms are substituted with at least one selected from the group consisting of halogen and isothiocyanate groups" means that 1 to 3 hydrogen atoms may be substituted with only halogen, only isothiocyanate groups, or both halogen and isothiocyanate groups.
In some embodiments of the invention, R 1-R5 is independently selected from a hydrogen atom, a fluorine atom, a cyano group, an isothiocyanate group, an alkyl group of C 1–C10 that is unsubstituted or substituted with 1-3 fluorine atoms or with phenyl isothiocyanate, an alkoxy group of C 1–C10 that is unsubstituted, an alkylthio group of C 1–C3 that is unsubstituted or substituted with 1-3 fluorine atoms, a phenoxy group that is substituted with 1-2 isothiocyanate groups, or an ester group of C 1-C5 that is unsubstituted, and R 1-R5 is not simultaneously hydrogen.
In some embodiments of the invention, R 1-R5 is independently selected from the group consisting of a hydrogen atom, a fluorine atom, a cyano group, an isothiocyanate group, a methyl group, an ethyl group, an n-decyl group, -CF 3、-OCH3、-OCH2CH3、-SCH3、-SCF3、-COOCH3,Or alternatively
In some embodiments of the present invention, preferably, the compound having the structure shown in formula I is selected from at least one of the compounds having the structure shown below:
In some embodiments of the invention, the mass of the compound having the structure of formula I is 0.1% to 6.0%, preferably 0.2% to 1.0% of the total mass of the electrolyte. Insufficient content of the compound having the structure shown in formula I may not form a strong interface passivation layer and effectively absorb trace water in the electrolyte, affecting the effect thereof. On the other hand, too much compound of the structure of formula I may cause the passivation layer to be too thick, thereby resulting in too large diffusion resistance of Li + and increased polarization.
In some embodiments of the invention, the organic solvent includes a chain ester and a cyclic ester.
Optionally, the chain ester includes one or more of DMC, EMC, DEC, MPC, DPhC, EA, b PA, MP, EP, PP, MB, EB.
When selecting an organic solvent, it is necessary to consider whether the selected organic solvent satisfies the requirements of high dielectric constant, low viscosity, low melting point, high boiling point, low cost, and the like. The chain ester has lower viscosity and good electrochemical stability, and can improve the low-temperature performance of the electrolyte. Although the use of a chain ester as an organic solvent for lithium ion electrolytes has the above advantages, the performance of a single organic solvent has not been satisfactory for the market, and thus it is also required to use a mixture with other organic solvents. The cyclic ester has high dielectric constant and high ionic conductivity, and can form a stable SEI film on the surface of the negative electrode, but has high viscosity. Therefore, the chain ester and the cyclic ester are mixed to be used as the organic solvent of the lithium ion battery electrolyte, so that the chain ester and the cyclic ester fully play a synergistic effect, and the performance of the electrolyte is improved together.
Optionally, the cyclic ester in the organic solvent comprises one or more of carbon EC, PC, BC, FEC, γ -GBL.
Specifically, in some embodiments of the invention, the chain ester is selected from EC and the cyclic ester is selected from DEC or DMC or a combination of DEC and DMC.
In some embodiments of the present invention, the mass of the chain ester is 30-80% of the total mass of the electrolyte, the mass of the cyclic ester is 15-50% of the total mass of the electrolyte, and the mass ratio of the chain ester to the cyclic ester is (5-9): 2-4.
Preferably, the mass ratio of the chain ester to the cyclic ester may be (5-7): (2-3), (7-9): (3-4), or the like. The mass ratio of the chain ester to the cyclic ester is reasonably controlled, so that the organic solvent has the advantages of better dielectric constant and viscosity, lower melting point, higher boiling point and the like.
In some embodiments of the invention, the lithium salt includes LiPF 6 and a second lithium salt, the second lithium salt including one or more of LiBF 4, liBOB, liDFOB, liDFOP, liFSI, and LiTFSI.
LiPF 6 has proper solubility and higher ionic conductivity in organic solvent, can form a stable passivation film on the surface of an Al foil current collector, and can form a stable SEI film on the surface of a graphite electrode by cooperating with carbonate solvent. However, liPF 6 has poor thermal stability and is liable to undergo decomposition reaction. Therefore, the performance of the lithium salt can be improved by the composite use with the second lithium salt.
In some embodiments of the invention, the second lithium salt is preferably LiFSI, liBF 4 or LiBOB, more preferably LiFSI. Because LiFSI has the advantages of high conductivity, low water sensitivity, good thermal stability and the like.
In some embodiments of the invention, liPF 6 is 12-15% by mass of the total electrolyte mass, preferably 12% -13%, 13% -14%, 14% -15% and so on.
In some embodiments of the invention, the second lithium salt comprises 0-10% by weight of the electrolyte, preferably may be 0-3%, more preferably 0.5% -1%.
In some embodiments of the application, liPF 6 comprises 80% -100% of the total mass of LiPF 6 and the second lithium salt, which comprises 0-15% of the total mass of LiPF 6 and the second lithium salt. By regulating the ratio of the lithium salt to the second lithium salt, the better performance of the lithium ion battery electrolyte is exerted.
The invention also provides a preparation method of the electrolyte, which comprises the following steps:
Adding lithium salt into organic solvent, mixing compound with structure shown in formula I into the mixed solution to obtain electrolyte, and further mixing lithium salt and organic solvent at temperature not higher than 2deg.C.
Since the electrolyte temperature increases due to heat release when the lithium salt is added, and the lithium salt is decomposed to some extent by heat, it is necessary to control the temperature at a low temperature when the lithium salt is mixed with the solvent.
In another aspect of the invention, a lithium ion battery using the above electrolyte is provided.
In some embodiments of the invention, the lithium ion battery further comprises a positive electrode active material, a negative electrode active material, and the electrolyte.
In some embodiments of the present application, the positive electrode active material chemical formula includes LiaNi xCoyMnzO2, where 0.9 ∈a ∈ 1.1,0.6 ∈x ∈ 0.8,0.1 ∈y ∈ 0.2,0.1 ∈z ∈0.2, and x+y+z=1.
In some embodiments of the invention, the negative electrode active material includes one or more of silicon, silicon carbon, silicon oxygen, silicon metal compounds.
The electrolyte and the lithium ion battery provided by the invention are described in detail below with reference to specific examples.
The specific experimental procedures or conditions are not noted in the examples and may be followed by the operations or conditions of conventional experimental procedures described in the literature in this field. The reagents or apparatus used were conventional reagent products commercially available without the manufacturer's knowledge.
Wherein B is phenyl isothiocyanate, and the structural formula is as follows:
Examples 1 to 16 and comparative examples 1 to 4 respectively provide an electrolyte and a lithium ion battery comprising the electrolyte, and the composition of the electrolyte and the performance of the battery are shown in table 1.
The preparation method of the electrolyte comprises the steps of weighing and uniformly mixing an organic solvent according to a mass ratio in a glove box (H 2O<1ppm,O2 <1 ppm) filled with argon at room temperature, adding lithium salt, continuously stirring and cooling by using dry ice, ensuring that the temperature of the electrolyte is not increased by more than 2 ℃ in the process of adding the lithium salt, adding a compound or B with a structure shown in a formula I, and uniformly stirring to obtain the electrolyte.
The lithium ion battery comprises a positive pole piece, a negative pole piece and electrolyte prepared by each group. The preparation method comprises the steps of stacking the positive pole piece, the diaphragm and the negative pole piece in sequence, enabling the diaphragm to be positioned between the positive pole piece and the negative pole piece, winding, hot-pressing and shaping, welding the electrode lugs to obtain a bare cell, placing the bare cell in an outer packaging aluminum-plastic film, placing in an oven at 85 ℃ for baking for 24 hours, injecting the prepared electrolyte into the dried battery, standing, forming and capacity-dividing to obtain the lithium ion soft package battery.
The positive electrode plate is prepared by uniformly mixing positive electrode active materials Li (Ni 0.8Mn0.1Co0.1)O2 (NMC 811), conductive agent acetylene black (Super P) and binder polyvinylidene fluoride (PVDF) according to the mass ratio NMC811:super P:PVDF=94:3:3, uniformly dispersing the mixture in 1-methyl-2-pyrrolidone (NMP) to prepare uniform black slurry, coating the mixed slurry on two sides of an aluminum foil, baking, rolling and cutting the aluminum foil to obtain the positive electrode plate.
The negative electrode plate is prepared by uniformly mixing negative electrode active material components of silicon oxide (SiO), artificial graphite, conductive agent acetylene black (Super P) and binder (SBR) according to the mass ratio of silicon oxide to artificial graphite to Super P to SBR=11:83:3:3, uniformly dispersing the mixture in deionized water to prepare uniform black slurry, coating the mixed slurry on two sides of a copper foil, baking, rolling and cutting the copper foil to obtain the negative electrode plate.
Battery performance test
1. And (3) testing normal-temperature direct-current internal resistance (DCR), namely charging the soft package battery 1C obtained in the examples and the comparative examples to 4.4V at 25+/-2 ℃, discharging for 30min at 1C capacity, adjusting to 50% SOC, and then recharging for 10s at 5C constant-current pulse discharge, so as to calculate the DCR value of the battery, and recording as the initial DCR. Dcr= (voltage before pulse discharge-voltage after pulse discharge)/discharge current x 100%. After the battery was stored at a high temperature of 60 ℃ for 30 days, the DCR was again tested and recorded as the post-storage DCR when the battery was completely cooled to 25±2 ℃. DCR change rate= (DCR after storage-initial DCR)/initial dcr×100%, and the recording results are shown in table 1.
2. And (3) testing normal temperature cycle performance, namely testing the soft package batteries of the examples and the comparative examples in a charge-discharge cycle mode within a range of 2.8-4.4V at a charge-discharge multiplying power of 1C/1C at 25+/-2 ℃, and recording the first-week discharge specific capacity of the batteries and the discharge specific capacity after 1000 cycles. Capacity retention rate of 1000 turns = specific discharge capacity of 1000 turns/specific discharge capacity of first week x 100%, and the recorded data are shown in table 1.
3. High temperature storage Property the soft pack batteries of examples and comparative examples were subjected to a charge-discharge test at 60.+ -. 2 ℃ at a charge-discharge rate of 1C/1C in the range of 2.8-4.4V, and the first week discharge specific capacity of the batteries was recorded, and then stored at 60.+ -. 2 ℃ for 30 days, and again subjected to a charge-discharge test and the discharge specific capacity was recorded. Storage capacity retention at 60 ℃ = specific discharge capacity after 7 days/specific discharge capacity at first week x 100%, recorded data are shown in table 1.
4. And (3) high-temperature gas production test, namely constant-current charging the soft package batteries of the examples and the comparative examples to 4.4V at the rate of 1C at 25+/-2 ℃ and constant-voltage charging to the current of less than 0.05C at the constant voltage of 4.4V, so that the soft package batteries are in a 4.4V full charge state. The volume of the fully charged battery before storage was measured and noted as V 0, and then the fully charged battery was placed in a 70±2 ℃ oven, after two days the battery was removed and immediately the stored volume was measured and noted as V 1. The storage volume expansion rate at 70 ℃ = (V 1–V0)/V0 ×100%, and the obtained results are shown in table 1.
Table 1 battery performance results table
Wherein the proportion of the organic solvent in the table belongs to the mass ratio.
As can be seen from the above table, examples 1 to 7 after addition of A1 are effective in reducing the storage volume expansion rate at 70 ℃ compared to comparative example 1, examples 8 to 12 after addition of A2 are effective in reducing the storage volume expansion rate at 70 ℃ compared to comparative example 2, and examples 13 to 16 after addition of A3 are effective in reducing the storage volume expansion rate at 70 ℃ compared to comparative example 3. The addition of A1-A3 can improve the high-temperature storage gas production performance of the battery.
Examples 1 to 7 are compared with comparative example 1, examples 8 to 12 are compared with comparative example 2, and examples 13 to 16 are compared with comparative example 3, showing that DCR of the battery can be further reduced and the effect of the high temperature storage process on DCR can be significantly improved while improving the normal temperature cycle performance and the high temperature storage gas generating performance of the battery by limiting the mass of the compound having the structure shown in formula I to a preferred range. The electrolyte systems with different contents A1, A2 or A3 were compared, wherein the properties of the A1, A2 or A3 electrolytes added in an amount of 0.5% by weight were better.
It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211273118.2A CN115411368B (en) | 2022-10-18 | 2022-10-18 | Electrolyte and lithium-ion battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211273118.2A CN115411368B (en) | 2022-10-18 | 2022-10-18 | Electrolyte and lithium-ion battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115411368A CN115411368A (en) | 2022-11-29 |
| CN115411368B true CN115411368B (en) | 2025-10-14 |
Family
ID=84168235
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211273118.2A Active CN115411368B (en) | 2022-10-18 | 2022-10-18 | Electrolyte and lithium-ion battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115411368B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119764566B (en) * | 2024-12-27 | 2026-04-21 | 中创新航科技集团股份有限公司 | A lithium-ion battery |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006012713A (en) * | 2004-06-29 | 2006-01-12 | Asahi Denka Kogyo Kk | Non-aqueous electrolyte and non-aqueous electrolyte secondary battery using the electrolyte |
| CN112397785A (en) * | 2020-11-16 | 2021-02-23 | 合肥国轩高科动力能源有限公司 | High-voltage low-impedance lithium ion battery electrolyte and lithium ion battery |
-
2022
- 2022-10-18 CN CN202211273118.2A patent/CN115411368B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006012713A (en) * | 2004-06-29 | 2006-01-12 | Asahi Denka Kogyo Kk | Non-aqueous electrolyte and non-aqueous electrolyte secondary battery using the electrolyte |
| CN112397785A (en) * | 2020-11-16 | 2021-02-23 | 合肥国轩高科动力能源有限公司 | High-voltage low-impedance lithium ion battery electrolyte and lithium ion battery |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115411368A (en) | 2022-11-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110783626B (en) | Electrolytes, Lithium Ion Batteries, Battery Modules, Battery Packs and Devices | |
| CN109728340B (en) | Lithium Ion Battery | |
| CN119029318A (en) | Lithium-ion secondary battery, battery module, battery pack, and power-consuming device | |
| CN114142091A (en) | Non-aqueous electrolyte of lithium ion battery and lithium ion battery | |
| JP2021534555A (en) | Lithium ion secondary battery | |
| CN113130992B (en) | Non-aqueous electrolyte and lithium ion battery | |
| CN103515650A (en) | Non-aqueous electrolyte for lithium ion battery, and application thereof | |
| WO2025025537A1 (en) | Secondary battery and electrical device | |
| CN118281336A (en) | Electrolyte with trace lithium nitrate as additive and electrochemical device | |
| CN112271335A (en) | Electrolyte of lithium ion battery suitable for high-nickel cathode material and lithium ion battery | |
| CN115411368B (en) | Electrolyte and lithium-ion battery | |
| CN113889667B (en) | High-voltage electrolyte adaptive to lithium cobaltate battery capable of being charged quickly and application of high-voltage electrolyte | |
| CN113948775B (en) | Electrolyte and battery comprising same | |
| CN115911534A (en) | A lithium ion battery electrolyte and a lithium ion battery containing the electrolyte | |
| JP2023539963A (en) | Lithium ion secondary batteries, battery modules, battery packs and power consumption devices | |
| CN112310341B (en) | Lithium ion battery electrode and lithium ion battery comprising same | |
| CN114315903B (en) | A kind of cyclic bisphosphate compound, its preparation method and its application | |
| CN116646598A (en) | Electrolyte and secondary battery | |
| CN112670581B (en) | Suitable for non-aqueous electrolytes of -20℃~60℃ and lithium-ion batteries based on them | |
| CN116315078A (en) | A kind of electrolyte and secondary battery | |
| CN116247299A (en) | A kind of lithium ion battery non-aqueous electrolyte and application thereof | |
| CN116315087A (en) | Electrolyte and lithium-ion battery | |
| CN118073650A (en) | Electrolyte and secondary battery | |
| CN115020812A (en) | An electrolyte and a lithium ion battery containing the same | |
| CN114709481A (en) | Non-aqueous electrolyte and lithium ion battery thereof |
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 |
Address after: 518107 1-2 Floor, Building A, Xinwangda Industrial Park, No. 18 Tangjianan Road, Gongming Street, Guangming New District, Shenzhen City, Guangdong Province Applicant after: Xinwangda Power Technology Co.,Ltd. Address before: 518107 1-2 Floor, Building A, Xinwangda Industrial Park, No. 18 Tangjianan Road, Gongming Street, Guangming New District, Shenzhen City, Guangdong Province Applicant before: SUNWODA ELECTRIC VEHICLE BATTERY Co.,Ltd. |
|
| CB02 | Change of applicant information | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |