CN112366353B - Lithium ion battery electrolyte containing propylene carbonate - Google Patents
Lithium ion battery electrolyte containing propylene carbonate Download PDFInfo
- Publication number
- CN112366353B CN112366353B CN202011242404.3A CN202011242404A CN112366353B CN 112366353 B CN112366353 B CN 112366353B CN 202011242404 A CN202011242404 A CN 202011242404A CN 112366353 B CN112366353 B CN 112366353B
- Authority
- CN
- China
- Prior art keywords
- carbonate
- stage
- solvent
- electrolyte
- ion battery
- 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
- 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
-
- 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
The invention discloses a propylene carbonate-containing lithium ion battery electrolyte, which comprises the following components: the first-stage electrolyte comprises a first-stage solvent, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.6-1.8 mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate is 1: 4-5, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 5-6: 2-3, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent; the second-stage solvent consists of cyclic carbonate, chain carbonate and propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate is 1: 4-5, and the cyclic carbonate does not contain the propylene carbonate in the second-stage solvent; the mass ratio of the first-stage electrolyte to the second-stage solvent is 8-9: 1. Based on the electrolyte, the cycle performance of the lithium ion battery can be improved.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a propylene carbonate-containing lithium ion battery electrolyte.
Background
A lithium ion battery is a secondary battery (rechargeable battery) that mainly operates by movement of lithium ions between a positive electrode and a negative electrode. During the charge and discharge process, lithium ions are intercalated and deintercalated between the two electrodes: during charging, lithium ions are extracted from the positive electrode and are inserted into the negative electrode through the electrolyte, and the negative electrode is in a lithium-rich state; the opposite is true during discharge. With the more and more common application of lithium ion batteries, the requirements on the cycle performance, the high and low temperature performance and the like of the lithium ion batteries are higher and higher. At present, in order to improve the high-low temperature performance of the lithium ion battery, a mode of adding propylene carbonate into an electrolyte of the lithium ion battery is often adopted. However, propylene carbonate is easily co-inserted into the graphite electrode, resulting in a decrease in cycle performance of the lithium ion battery.
Disclosure of Invention
An object of the present invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described hereinafter.
An object of the present invention is to provide a lithium ion battery electrolyte containing propylene carbonate, which can improve cycle performance of a lithium ion battery.
To achieve these objects and other advantages in accordance with the present invention, there is provided a lithium ion battery electrolyte containing propylene carbonate, the electrolyte comprising:
the electrolyte comprises a first-stage electrolyte, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.6-1.8 mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1: 4-5, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 5-6: 2-3, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent;
the secondary solvent is composed of cyclic carbonate, chain carbonate and propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate in the secondary solvent is 1: 4-5, and the cyclic carbonate does not contain propylene carbonate in the secondary solvent;
the mass ratio of the first-stage electrolyte to the second-stage solvent is 8-9: 1.
Preferably, in the lithium ion battery electrolyte containing propylene carbonate, the cyclic carbonate in the first-stage solvent is ethylene carbonate, and the chain carbonate in the first-stage solvent is one or more selected from dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate; the cyclic carbonate in the second-stage solvent is ethylene carbonate, and the chain carbonate in the second-stage solvent is one or more selected from dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate.
Preferably, in the propylene carbonate-containing lithium ion battery electrolyte, the conductive lithium salt in the first-stage electrolyte is LiPF6。
Preferably, in the electrolyte of the lithium ion battery containing propylene carbonate, the concentration of the conductive lithium salt in the first-stage electrolyte in the first-stage solvent is 1.8 mol/L.
Preferably, in the lithium ion battery electrolyte containing propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1:5, and the mass ratio of the first-stage solvent to the fluoropropylene carbonate is 5: 2.
Preferably, in the lithium ion battery electrolyte containing propylene carbonate, the mass ratio of the cyclic carbonate, the chain carbonate and the propylene carbonate in the second-stage solvent is 1:5: 5.
Preferably, in the electrolyte of the lithium ion battery containing the propylene carbonate, the mass ratio of the first-stage electrolyte to the second-stage solvent is 8: 1.
Preferably, the lithium ion battery electrolyte containing propylene carbonate is prepared by the following method:
firstly, uniformly mixing cyclic carbonate and chain carbonate contained in a first-stage solvent in proportion under an inert atmosphere, adding the fluoropropylene carbonate into the first-stage solvent to form a mixed solvent, adding a conductive lithium salt into the mixed solvent, and fully and uniformly stirring to prepare a first-stage electrolyte;
step two, uniformly mixing the cyclic carbonate, the chain carbonate and the propylene carbonate contained in the second-stage solvent in proportion, and fully and uniformly stirring to prepare the second-stage solvent;
step three, injecting the first-stage electrolyte into the lithium ion battery at one time;
and step four, dividing the second-stage solvent into multiple parts, and continuously injecting the second-stage solvent into the lithium ion battery into which the first-stage electrolyte is injected for multiple times, wherein one part of the second-stage solvent is injected into the lithium ion battery into which the first-stage electrolyte is injected each time.
Preferably, in the fourth step, after the first-stage electrolyte is injected into the lithium ion battery for 5-10 seconds at one time in the third step, the second-stage solvent is continuously injected into the lithium ion battery into which the first-stage electrolyte is injected; and injecting a second-stage solvent into the lithium ion battery injected with the first-stage electrolyte twice in an adjacent manner at an interval of 2-3 s.
The invention at least comprises the following beneficial effects:
the invention provides a propylene carbonate-containing lithium ion battery electrolyte, which comprises the following components: the electrolyte comprises a first-stage electrolyte, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.6-1.8 mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1: 4-5, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 5-6: 2-3, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent; the secondary solvent is composed of cyclic carbonate, chain carbonate and propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate in the secondary solvent is 1: 4-5, and the cyclic carbonate does not contain propylene carbonate in the secondary solvent; the mass ratio of the first-stage electrolyte to the second-stage solvent is 8-9: 1. According to the invention, the electrolyte is divided into two parts, the first-stage electrolyte contains conductive lithium salt and fluorinated propylene carbonate, the propylene carbonate is used as a component in the second-stage solvent, when the lithium ion battery is manufactured, the first-stage electrolyte is injected into the lithium ion battery, and then the second-stage solvent containing the propylene carbonate is injected into the lithium ion battery, so that co-intercalation of the propylene carbonate to a graphite electrode can be effectively inhibited, and the fluorinated propylene carbonate is added into the first-stage electrolyte, so that a compact and stable SEI film is preferentially formed on the surface of the graphite electrode, and the co-intercalation of the propylene carbonate on the surface of the graphite electrode is further inhibited. Based on the electrolyte, the cycle performance of the lithium ion battery can be improved.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
Detailed Description
The present invention is described in further detail below to enable those skilled in the art to practice the invention with reference to the description.
The invention provides a propylene carbonate-containing lithium ion battery electrolyte, which comprises the following components: the electrolyte comprises a first-stage electrolyte, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.6-1.8 mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1: 4-5, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 5-6: 2-3, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent; the secondary solvent is composed of cyclic carbonate, chain carbonate and propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate in the secondary solvent is 1: 4-5, and the cyclic carbonate does not contain propylene carbonate in the secondary solvent; the mass ratio of the first-stage electrolyte to the second-stage solvent is 8-9: 1.
The present invention divides the electrolyte into two parts, a first stage electrolyte containing a conductive lithium salt and propylene fluoro carbonate and a second stage solvent containing propylene carbonate. The first-stage electrolyte contains conductive lithium salt and fluorinated propylene carbonate, and the propylene carbonate is used as a component in the second-stage solvent. When the lithium ion battery is manufactured, the first-stage electrolyte is injected into the lithium ion battery, and then the second-stage solvent containing the propylene carbonate is injected into the lithium ion battery, so that co-insertion of the propylene carbonate and lithium ions to a graphite electrode can be effectively inhibited, and adverse effects on the cycle performance of the battery caused by co-insertion of the propylene carbonate to the graphite electrode are inhibited. The fluorinated propylene carbonate is added into the first-stage electrolyte, so that a compact and stable SEI film is formed on the surface of the graphite electrode preferentially, and co-embedding of the propylene carbonate on the surface of the graphite electrode can be further inhibited. In conclusion, based on the electrolyte provided by the invention, the cycle performance of the lithium ion battery can be improved.
In a preferred embodiment, in the lithium ion battery electrolyte containing propylene carbonate, the cyclic carbonate in the first-stage solvent is ethylene carbonate, and the chain carbonate in the first-stage solvent is one or more selected from dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate; the cyclic carbonate in the second-stage solvent is ethylene carbonate, and the chain carbonate in the second-stage solvent is one or more selected from dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate.
In a preferred embodiment, in the electrolyte of the lithium ion battery containing propylene carbonate, the conductive lithium salt in the first-stage electrolyte is LiPF6。
In a preferred embodiment, in the electrolyte of the lithium ion battery containing propylene carbonate, the concentration of the conductive lithium salt in the first-stage electrolyte in the first-stage solvent is 1.8 mol/L.
In a preferred embodiment, in the lithium ion battery electrolyte containing propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1:5, and the mass ratio of the first-stage solvent to the fluoropropylene carbonate is 5: 2.
In a preferred embodiment, in the lithium ion battery electrolyte containing propylene carbonate, the mass ratio of the cyclic carbonate, the chain carbonate and the propylene carbonate in the second-stage solvent is 1:5: 5.
In a preferred embodiment, in the lithium ion battery electrolyte containing propylene carbonate, the mass ratio of the first-stage electrolyte to the second-stage solvent is 8: 1.
In a preferred embodiment, the lithium ion battery electrolyte containing propylene carbonate is prepared by the following method:
firstly, uniformly mixing cyclic carbonate and chain carbonate contained in a first-stage solvent in proportion under an inert atmosphere, adding the fluoropropylene carbonate into the first-stage solvent to form a mixed solvent, adding a conductive lithium salt into the mixed solvent, and fully and uniformly stirring to prepare a first-stage electrolyte;
step two, uniformly mixing the cyclic carbonate, the chain carbonate and the propylene carbonate contained in the second-stage solvent in proportion, and fully and uniformly stirring to prepare the second-stage solvent;
step three, injecting the first-stage electrolyte into the lithium ion battery at one time;
and step four, dividing the second-stage solvent into multiple parts, and continuously injecting the second-stage solvent into the lithium ion battery into which the first-stage electrolyte is injected for multiple times, wherein one part of the second-stage solvent is injected into the lithium ion battery into which the first-stage electrolyte is injected each time.
Specifically, when the lithium ion battery is manufactured, the first-stage electrolyte is injected into the lithium ion battery, and then the second-stage solvent containing the propylene carbonate is injected into the lithium ion battery, so that co-insertion of the propylene carbonate and lithium ions to a graphite electrode can be effectively inhibited, and adverse effects on the cycle performance of the battery caused by co-insertion of the propylene carbonate to the graphite electrode are inhibited. The fluorinated propylene carbonate is added into the first-stage electrolyte, so that a compact and stable SEI film is formed on the surface of the graphite electrode preferentially, and co-embedding of the propylene carbonate on the surface of the graphite electrode can be further inhibited. In addition, the secondary solvent is injected for multiple times, so that co-intercalation of the propylene carbonate to the graphite electrode can be further inhibited, and the cycle performance of the lithium ion battery is further improved.
In a preferred embodiment, in the fourth step, after the first-stage electrolyte is injected into the lithium ion battery at one time for 5 to 10 seconds after the first-stage electrolyte is injected into the lithium ion battery at one time in the third step, the second-stage solvent is continuously injected into the lithium ion battery into which the first-stage electrolyte is injected; and injecting a second-stage solvent into the lithium ion battery injected with the first-stage electrolyte twice in an adjacent manner at an interval of 2-3 s.
In order to further improve the effect of injecting the first-stage electrolyte and the second-stage solvent at intervals, the second-stage solvent can be injected at intervals for a short time after the first-stage electrolyte is injected, and the second-stage solvent is divided into a plurality of parts and injected at intervals for a plurality of times, so that co-insertion of propylene carbonate to a graphite electrode can be effectively inhibited, the injection amount can be increased, and the purpose of improving the cycle performance of the lithium ion battery can be achieved.
Example one
The composition of the lithium ion battery electrolyte in the embodiment is as follows:
the electrolyte comprises a first-stage electrolyte, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.8mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1:5, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 5:2, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent; the cyclic carbonate in the first-stage solvent is ethylene carbonate, and the chain carbonate in the first-stage solvent is dimethyl carbonate; the conductive lithium salt in the first-stage electrolyte is LiPF6(ii) a The secondary solvent consists of cyclic carbonate, chain carbonate and propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate in the secondary solvent is 1:5:5, and the cyclic carbonate does not contain the propylene carbonate in the secondary solvent; the cyclic carbonate in the second-stage solvent is ethylene carbonate, and the chain carbonate in the second-stage solvent is dimethyl carbonate; wherein, the firstThe mass ratio of the first-stage electrolyte to the second-stage solvent is 8: 1.
Based on the above composition, a lithium ion battery was prepared according to the following method:
firstly, uniformly mixing cyclic carbonate and chain carbonate contained in a first-stage solvent in proportion under an inert atmosphere, adding the fluoropropylene carbonate into the first-stage solvent to form a mixed solvent, adding a conductive lithium salt into the mixed solvent, and fully and uniformly stirring to prepare a first-stage electrolyte;
step two, uniformly mixing the cyclic carbonate, the chain carbonate and the propylene carbonate contained in the second-stage solvent in proportion, and fully and uniformly stirring to prepare the second-stage solvent;
step three, injecting the first-stage electrolyte into the lithium ion battery at one time;
step four, dividing the secondary solvent into a plurality of parts; after the first-stage electrolyte is injected into the lithium ion battery for 5-10 seconds at one time in the third step, continuously injecting the second-stage solvent into the lithium ion battery into which the first-stage electrolyte is injected for 2 times, wherein one second-stage solvent is injected into the lithium ion battery into which the first-stage electrolyte is injected each time; and injecting a second-stage solvent into the lithium ion battery injected with the first-stage electrolyte twice in an adjacent manner at an interval of 2-3 s.
The cycle performance of the lithium ion battery prepared in this example was examined. The test method comprises the following steps: charging at 25 deg.C for 150 min by constant current and constant voltage mode 1C, and discharging at constant current 1C to 2.75V to cut off. When the test was completed when the one-time discharge time was less than 36 minutes, the capacity retention ratio at the end of the test was measured.
Based on the above testing process, after 300 cycles, the capacity retention rate of the lithium ion battery prepared in this embodiment is 92.3%.
Example two
The composition of the lithium ion battery electrolyte in the embodiment is as follows:
the electrolyte comprises a first-stage electrolyte, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.6mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1:4, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 5:3, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent; the cyclic carbonate in the first-stage solvent is ethylene carbonate, and the chain carbonate in the first-stage solvent is diethyl carbonate; the cyclic carbonate in the second-stage solvent is ethylene carbonate, and the chain carbonate in the second-stage solvent is diethyl carbonate; the conductive lithium salt in the first-stage electrolyte is LiPF6(ii) a The secondary solvent consists of cyclic carbonate, chain carbonate and propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate in the secondary solvent is 1:4:4, and the cyclic carbonate does not contain the propylene carbonate in the secondary solvent; wherein the mass ratio of the first-stage electrolyte to the second-stage solvent is 9: 1.
Based on the above composition, a lithium ion battery was prepared according to the following method:
firstly, uniformly mixing cyclic carbonate and chain carbonate contained in a first-stage solvent in proportion under an inert atmosphere, adding the fluoropropylene carbonate into the first-stage solvent to form a mixed solvent, adding a conductive lithium salt into the mixed solvent, and fully and uniformly stirring to prepare a first-stage electrolyte;
step two, uniformly mixing the cyclic carbonate, the chain carbonate and the propylene carbonate contained in the second-stage solvent in proportion, and fully and uniformly stirring to prepare the second-stage solvent;
step three, injecting the first-stage electrolyte into the lithium ion battery at one time;
step four, dividing the secondary solvent into a plurality of parts; after the first-stage electrolyte is injected into the lithium ion battery for 5-10 seconds at one time in the third step, continuously injecting the second-stage solvent into the lithium ion battery into which the first-stage electrolyte is injected for 2 times, wherein one second-stage solvent is injected into the lithium ion battery into which the first-stage electrolyte is injected each time; and injecting a second-stage solvent into the lithium ion battery injected with the first-stage electrolyte twice in an adjacent manner at an interval of 2-3 s.
The cycle performance of the lithium ion battery prepared in this example was examined. The test method comprises the following steps: charging at 25 deg.C for 150 min by constant current and constant voltage mode 1C, and discharging at constant current 1C to 2.75V to cut off. When the test was completed when the one-time discharge time was less than 36 minutes, the capacity retention ratio at the end of the test was measured.
Based on the above testing process, after 300 cycles, the capacity retention rate of the lithium ion battery prepared in this embodiment is 92.4%.
EXAMPLE III
The composition of the lithium ion battery electrolyte in the embodiment is as follows:
the electrolyte comprises a first-stage electrolyte, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.8mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1:5, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 3:1, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent; the cyclic carbonate in the first-stage solvent is ethylene carbonate, and the chain carbonate in the first-stage solvent is methyl ethyl carbonate; the cyclic carbonate in the second-stage solvent is ethylene carbonate, and the chain carbonate in the second-stage solvent is methyl ethyl carbonate; the conductive lithium salt in the first-stage electrolyte is LiPF6(ii) a A second-stage solvent, wherein the second-stage solvent is a group consisting of cyclic carbonate, chain carbonate and propylene carbonateThe mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate in the second-stage solvent is 1:5:4, and the cyclic carbonate does not contain propylene carbonate in the second-stage solvent; wherein the mass ratio of the first-stage electrolyte to the second-stage solvent is 9: 1.
Based on the above composition, a lithium ion battery was prepared according to the following method:
firstly, uniformly mixing cyclic carbonate and chain carbonate contained in a first-stage solvent in proportion under an inert atmosphere, adding the fluoropropylene carbonate into the first-stage solvent to form a mixed solvent, adding a conductive lithium salt into the mixed solvent, and fully and uniformly stirring to prepare a first-stage electrolyte;
step two, uniformly mixing the cyclic carbonate, the chain carbonate and the propylene carbonate contained in the second-stage solvent in proportion, and fully and uniformly stirring to prepare the second-stage solvent;
step three, injecting the first-stage electrolyte into the lithium ion battery at one time;
step four, dividing the secondary solvent into a plurality of parts; after the first-stage electrolyte is injected into the lithium ion battery for 5-10 seconds at one time in the third step, continuously injecting the second-stage solvent into the lithium ion battery into which the first-stage electrolyte is injected for 2 times, wherein one second-stage solvent is injected into the lithium ion battery into which the first-stage electrolyte is injected each time; and injecting a second-stage solvent into the lithium ion battery injected with the first-stage electrolyte twice in an adjacent manner at an interval of 2-3 s.
The cycle performance of the lithium ion battery prepared in this example was examined. The test method comprises the following steps: charging at 25 deg.C for 150 min by constant current and constant voltage mode 1C, and discharging at constant current 1C to 2.75V to cut off. When the test was completed when the one-time discharge time was less than 36 minutes, the capacity retention ratio at the end of the test was measured.
Based on the above testing process, after 300 cycles, the capacity retention rate of the lithium ion battery prepared in this embodiment is 91.7%.
Example four
The composition of the lithium ion battery electrolyte in the embodiment is as follows:
the electrolyte comprises a first-stage electrolyte, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.6mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1:4, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 2:1, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent; the cyclic carbonate in the first-stage solvent is ethylene carbonate, and the chain carbonate in the first-stage solvent is dimethyl carbonate; the cyclic carbonate in the second-stage solvent is ethylene carbonate, and the chain carbonate in the second-stage solvent is diethyl carbonate; the conductive lithium salt in the first-stage electrolyte is LiPF6(ii) a The secondary solvent consists of cyclic carbonate, chain carbonate and propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate in the secondary solvent is 1:5:4, and the cyclic carbonate does not contain the propylene carbonate in the secondary solvent; wherein the mass ratio of the first-stage electrolyte to the second-stage solvent is 8: 1.
Based on the above composition, a lithium ion battery was prepared according to the following method:
firstly, uniformly mixing cyclic carbonate and chain carbonate contained in a first-stage solvent in proportion under an inert atmosphere, adding the fluoropropylene carbonate into the first-stage solvent to form a mixed solvent, adding a conductive lithium salt into the mixed solvent, and fully and uniformly stirring to prepare a first-stage electrolyte;
step two, uniformly mixing the cyclic carbonate, the chain carbonate and the propylene carbonate contained in the second-stage solvent in proportion, and fully and uniformly stirring to prepare the second-stage solvent;
step three, injecting the first-stage electrolyte into the lithium ion battery at one time;
step four, dividing the secondary solvent into a plurality of parts; after the first-stage electrolyte is injected into the lithium ion battery for 5-10 seconds at one time in the third step, continuously injecting the second-stage solvent into the lithium ion battery into which the first-stage electrolyte is injected for 2 times, wherein one second-stage solvent is injected into the lithium ion battery into which the first-stage electrolyte is injected each time; and injecting a second-stage solvent into the lithium ion battery injected with the first-stage electrolyte twice in an adjacent manner at an interval of 2-3 s.
The cycle performance of the lithium ion battery prepared in this example was examined. The test method comprises the following steps: charging at 25 deg.C for 150 min by constant current and constant voltage mode 1C, and discharging at constant current 1C to 2.75V to cut off. When the test was completed when the one-time discharge time was less than 36 minutes, the capacity retention ratio at the end of the test was measured.
Based on the above testing process, after 300 cycles, the capacity retention rate of the lithium ion battery prepared in this embodiment is 92.7%.
EXAMPLE five
The composition of the lithium ion battery electrolyte in the embodiment is as follows:
the electrolyte comprises a first-stage electrolyte, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.8mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1:5, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 5:3, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent; the cyclic carbonate in the first-stage solvent is ethylene carbonate, and the chain carbonate in the first-stage solvent is methyl ethyl carbonate; the cyclic carbonate in the second-stage solvent is ethylene carbonate, and the second stage solvent isThe chain carbonate in the solvent is dimethyl carbonate; the conductive lithium salt in the first-stage electrolyte is LiPF6(ii) a The secondary solvent consists of cyclic carbonate, chain carbonate and propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate in the secondary solvent is 1:4:5, and the cyclic carbonate does not contain the propylene carbonate in the secondary solvent; wherein the mass ratio of the first-stage electrolyte to the second-stage solvent is 8: 1.
Based on the above composition, a lithium ion battery was prepared according to the following method:
firstly, uniformly mixing cyclic carbonate and chain carbonate contained in a first-stage solvent in proportion under an inert atmosphere, adding the fluoropropylene carbonate into the first-stage solvent to form a mixed solvent, adding a conductive lithium salt into the mixed solvent, and fully and uniformly stirring to prepare a first-stage electrolyte;
step two, uniformly mixing the cyclic carbonate, the chain carbonate and the propylene carbonate contained in the second-stage solvent in proportion, and fully and uniformly stirring to prepare the second-stage solvent;
step three, injecting the first-stage electrolyte into the lithium ion battery at one time;
step four, dividing the secondary solvent into a plurality of parts; after the first-stage electrolyte is injected into the lithium ion battery for 5-10 seconds at one time in the third step, continuously injecting the second-stage solvent into the lithium ion battery into which the first-stage electrolyte is injected for 2 times, wherein one second-stage solvent is injected into the lithium ion battery into which the first-stage electrolyte is injected each time; and injecting a second-stage solvent into the lithium ion battery injected with the first-stage electrolyte twice in an adjacent manner at an interval of 2-3 s.
The cycle performance of the lithium ion battery prepared in this example was examined. The test method comprises the following steps: charging at 25 deg.C for 150 min by constant current and constant voltage mode 1C, and discharging at constant current 1C to 2.75V to cut off. When the test was completed when the one-time discharge time was less than 36 minutes, the capacity retention ratio at the end of the test was measured.
Based on the above testing process, after 300 cycles, the capacity retention rate of the lithium ion battery prepared in this embodiment is 91.6%.
While embodiments of the invention have been disclosed above, it is not intended to be limited to the uses set forth in the specification and examples. It can be applied to all kinds of fields suitable for the present invention. Additional modifications will readily occur to those skilled in the art. The invention is therefore not to be limited to the specific details described herein, without departing from the general concept as defined by the appended claims and their equivalents.
Claims (7)
1. The lithium ion battery electrolyte containing propylene carbonate is characterized by comprising the following components in parts by weight:
the electrolyte comprises a first-stage electrolyte, a conductive lithium salt and propylene carbonate fluoride, wherein the concentration of the conductive lithium salt in the first-stage solvent is 1.6-1.8 mol/L, the first-stage solvent consists of cyclic carbonate and chain carbonate, the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1: 4-5, the mass ratio of the first-stage solvent to the propylene carbonate fluoride is 5-6: 2-3, and the cyclic carbonate does not contain propylene carbonate in the first-stage solvent;
the secondary solvent is composed of cyclic carbonate, chain carbonate and propylene carbonate, the mass ratio of the cyclic carbonate to the chain carbonate to the propylene carbonate in the secondary solvent is 1: 4-5, and the cyclic carbonate does not contain propylene carbonate in the secondary solvent;
wherein the mass ratio of the first-stage electrolyte to the second-stage solvent is 8-9: 1;
the preparation method comprises the following steps:
firstly, uniformly mixing cyclic carbonate and chain carbonate contained in a first-stage solvent in proportion under an inert atmosphere, adding the fluoropropylene carbonate into the first-stage solvent to form a mixed solvent, adding a conductive lithium salt into the mixed solvent, and fully and uniformly stirring to prepare a first-stage electrolyte;
step two, uniformly mixing the cyclic carbonate, the chain carbonate and the propylene carbonate contained in the second-stage solvent in proportion, and fully and uniformly stirring to prepare the second-stage solvent;
step three, injecting the first-stage electrolyte into the lithium ion battery at one time;
dividing the second-stage solvent into multiple parts, and continuously injecting the second-stage solvent into the lithium ion battery injected with the first-stage electrolyte for multiple times, wherein one part of the second-stage solvent is injected into the lithium ion battery injected with the first-stage electrolyte every time; in the fourth step, after the first-stage electrolyte is injected into the lithium ion battery at one time in the third step for 5-10 seconds, the second-stage solvent is continuously injected into the lithium ion battery into which the first-stage electrolyte is injected; and injecting a second-stage solvent into the lithium ion battery injected with the first-stage electrolyte twice in an adjacent manner at an interval of 2-3 s.
2. The propylene carbonate-containing lithium ion battery electrolyte as claimed in claim 1, wherein the cyclic carbonate in the first-stage solvent is ethylene carbonate, and the chain carbonate in the first-stage solvent is one or more selected from dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate; the cyclic carbonate in the second-stage solvent is ethylene carbonate, and the chain carbonate in the second-stage solvent is one or more selected from dimethyl carbonate, diethyl carbonate and ethyl methyl carbonate.
3. The propylene carbonate-containing lithium ion battery electrolyte of claim 1, wherein the conductive lithium salt in the first stage electrolyte is LiPF6。
4. The propylene carbonate containing lithium ion battery electrolyte of claim 3, wherein the concentration of the conductive lithium salt in the first stage electrolyte in the first stage solvent is 1.8 mol/L.
5. The propylene carbonate-containing lithium ion battery electrolyte as claimed in claim 2, wherein the mass ratio of the cyclic carbonate to the chain carbonate in the first-stage solvent is 1:5, and the mass ratio of the first-stage solvent to the propylene fluoro carbonate is 5: 2.
6. The propylene carbonate-containing lithium ion battery electrolyte of claim 2, wherein the mass ratio of the cyclic carbonate, the chain carbonate and the propylene carbonate in the second-stage solvent is 1:5: 5.
7. The propylene carbonate-containing lithium ion battery electrolyte according to any one of claims 4 to 6, wherein the mass ratio of the first-stage electrolyte to the second-stage solvent is 8: 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011242404.3A CN112366353B (en) | 2020-11-09 | 2020-11-09 | Lithium ion battery electrolyte containing propylene carbonate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011242404.3A CN112366353B (en) | 2020-11-09 | 2020-11-09 | Lithium ion battery electrolyte containing propylene carbonate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112366353A CN112366353A (en) | 2021-02-12 |
| CN112366353B true CN112366353B (en) | 2021-11-02 |
Family
ID=74509246
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011242404.3A Active CN112366353B (en) | 2020-11-09 | 2020-11-09 | Lithium ion battery electrolyte containing propylene carbonate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112366353B (en) |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101420048A (en) * | 2007-10-26 | 2009-04-29 | 比亚迪股份有限公司 | Preparation of lithium ionic secondary cell |
| CN102201563A (en) * | 2010-03-24 | 2011-09-28 | 深圳市比克电池有限公司 | Method of injecting electrolyte into a lithium ion battery, and lithium ion battery prepared by the same |
| CN102280610A (en) * | 2011-07-12 | 2011-12-14 | 长沙业翔能源科技有限公司 | Liquid-injection process of low-temperature lithium ion battery cell |
| CN103647110A (en) * | 2013-12-06 | 2014-03-19 | 华瑞(新乡)化工有限公司 | Ultralow temperature discharge electrolyte of novel lithium ion battery |
| CN104577031A (en) * | 2013-10-28 | 2015-04-29 | 比亚迪股份有限公司 | Lithium ion power battery electrolyte injection and formation method and lithium ion power battery |
| CN105449282A (en) * | 2014-08-27 | 2016-03-30 | 江苏华盛精化工股份有限公司 | A fluoro-propylene carbonate based electrolyte and a lithium ion battery |
| CN107171023A (en) * | 2017-05-17 | 2017-09-15 | 中国第汽车股份有限公司 | A kind of low temperature electrolytes for Li-ion batteries |
| CN108987662A (en) * | 2018-06-15 | 2018-12-11 | 江西力能新能源科技有限公司 | A kind of production technology of novel cylindrical lithium battery |
| CN109728239A (en) * | 2019-01-07 | 2019-05-07 | 惠州亿纬锂能股份有限公司 | A kind of electrolyte filling method of battery and its lithium ion battery of preparation |
| CN111193067A (en) * | 2020-01-11 | 2020-05-22 | 山东理工大学 | Preparation method of flame-retardant electrolyte for lithium ion battery |
| CN111584927A (en) * | 2020-05-11 | 2020-08-25 | 烯望新能源科技(深圳)有限公司 | Method for improving electro-hydraulic wettability of lithium ion battery |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6271706B2 (en) * | 2014-03-14 | 2018-01-31 | 株式会社東芝 | Nonaqueous electrolyte secondary battery, battery pack and vehicle |
-
2020
- 2020-11-09 CN CN202011242404.3A patent/CN112366353B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101420048A (en) * | 2007-10-26 | 2009-04-29 | 比亚迪股份有限公司 | Preparation of lithium ionic secondary cell |
| CN102201563A (en) * | 2010-03-24 | 2011-09-28 | 深圳市比克电池有限公司 | Method of injecting electrolyte into a lithium ion battery, and lithium ion battery prepared by the same |
| CN102280610A (en) * | 2011-07-12 | 2011-12-14 | 长沙业翔能源科技有限公司 | Liquid-injection process of low-temperature lithium ion battery cell |
| CN104577031A (en) * | 2013-10-28 | 2015-04-29 | 比亚迪股份有限公司 | Lithium ion power battery electrolyte injection and formation method and lithium ion power battery |
| CN103647110A (en) * | 2013-12-06 | 2014-03-19 | 华瑞(新乡)化工有限公司 | Ultralow temperature discharge electrolyte of novel lithium ion battery |
| CN105449282A (en) * | 2014-08-27 | 2016-03-30 | 江苏华盛精化工股份有限公司 | A fluoro-propylene carbonate based electrolyte and a lithium ion battery |
| CN107171023A (en) * | 2017-05-17 | 2017-09-15 | 中国第汽车股份有限公司 | A kind of low temperature electrolytes for Li-ion batteries |
| CN108987662A (en) * | 2018-06-15 | 2018-12-11 | 江西力能新能源科技有限公司 | A kind of production technology of novel cylindrical lithium battery |
| CN109728239A (en) * | 2019-01-07 | 2019-05-07 | 惠州亿纬锂能股份有限公司 | A kind of electrolyte filling method of battery and its lithium ion battery of preparation |
| CN111193067A (en) * | 2020-01-11 | 2020-05-22 | 山东理工大学 | Preparation method of flame-retardant electrolyte for lithium ion battery |
| CN111584927A (en) * | 2020-05-11 | 2020-08-25 | 烯望新能源科技(深圳)有限公司 | Method for improving electro-hydraulic wettability of lithium ion battery |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112366353A (en) | 2021-02-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106505249B (en) | Lithium ion battery electrolyte and lithium ion battery containing same | |
| US10033216B2 (en) | Initial charging method and production method for lithium-ion battery | |
| CN101154747B (en) | Formation method for lithium ion secondary battery | |
| CN101420048A (en) | Preparation of lithium ionic secondary cell | |
| CN110218276A (en) | A kind of cyclic carbonate ester base polymer electrolyte being prepared in situ and its application in solid state lithium battery | |
| CN110611121B (en) | Electrolyte and lithium ion battery containing same | |
| CN104067433A (en) | Nonaqueous electrolyte solution and nonaqueous electrolyte battery using same | |
| CN110797575A (en) | Non-aqueous electrolyte of lithium ion battery and lithium ion battery using same | |
| CN109687026B (en) | High-voltage ternary lithium ion battery electrolyte and lithium ion battery containing same | |
| CN106099185A (en) | A kind of electrolyte and include the lithium ion battery of this electrolyte | |
| CN108390098B (en) | High-voltage lithium ion battery electrolyte and high-voltage lithium ion battery | |
| CN112366353B (en) | Lithium ion battery electrolyte containing propylene carbonate | |
| CN100470884C (en) | A battery anode and lithium ion battery and their preparing method | |
| CN112490505A (en) | Electrolyte additive, non-aqueous electrolyte and lithium ion battery thereof | |
| KR20160063905A (en) | Electrolyte solution for secondary battery and additive therefor | |
| CN108767316A (en) | A kind of ternary material system lithium-ion battery electrolytes and lithium ion battery | |
| CN104157903A (en) | High-voltage lithium ion battery carbonate-based electrolyte solution and preparation method and application thereof | |
| CN113013489A (en) | Electrolyte and lithium ion battery comprising same | |
| CN113921904A (en) | Electrolyte solution and lithium secondary battery | |
| CN113078357A (en) | High-voltage lithium ion battery non-aqueous electrolyte and lithium ion battery | |
| CN111048839A (en) | Lithium ion battery electrolyte with good low-temperature discharge characteristic and lithium ion battery | |
| CN112531208A (en) | Lithium ion battery non-aqueous electrolyte and lithium ion battery | |
| CN111834666A (en) | Non-aqueous electrolyte of lithium ion battery for electronic cigarette and lithium ion battery thereof | |
| CN110556579A (en) | Electrolyte and lithium ion battery containing same | |
| CN115084679B (en) | Method for recovering capacity of retired lithium ion battery |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |