CN102332608A - Lithium ion battery electrolyte and lithium ion battery - Google Patents
Lithium ion battery electrolyte and lithium ion battery Download PDFInfo
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- CN102332608A CN102332608A CN201110282636A CN201110282636A CN102332608A CN 102332608 A CN102332608 A CN 102332608A CN 201110282636 A CN201110282636 A CN 201110282636A CN 201110282636 A CN201110282636 A CN 201110282636A CN 102332608 A CN102332608 A CN 102332608A
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- carbonate
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- battery electrolytes
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention discloses a lithium ion battery electrolyte. The electrolyte comprises conductive lithium salt, mixed carbonic ester solvent and additives, the additives include vinylene carbonate as a reduction type film-forming additive and methyl phenyl carbonate as a reaction type film-forming additive, and the two different types of added film-forming additives have a synergistic effect, which can help to enhance the cycle performance of a battery.
Description
Technical field
The present invention relates to lithium ion battery and make the field, particularly relate to a kind of lithium-ion battery electrolytes, lithium ion battery.
Background technology
Lithium ion battery is in the first charge-discharge process; Can show at both positive and negative polarity and form one deck solid electrolyte interface film (solid electrolyte interfacial; Be abbreviated as the SEI film), this tunic only allows lithium ion to see through, thereby stops the further reaction of solvent molecule.The SEI film film forming characteristics of electrolyte is to the lithium ion battery charge-discharge performance, and especially cycle performance has material impact.Physicochemical properties such as the chemical composition of SEI film, structure, texture and stability are the keys of decision carbon in lithium ion battery negative pole/electrolyte compatibility.
Generally, the electrolyte of being made up of EC and DMC, DEC and EMC has good film forming characteristics, need not add film for additive and just can form SEI film preferably, but in this process, can produce more CO, CO
2, CH
4, C
2H
4Gas (J.Electrochem.Soc.154 (2007) A449).This kind electrolyte is unfavorable for the performance of lithium ion battery cryogenic property in addition; For this reason, consider to replace EC, but PC can embed graphite linings altogether with the better PC of low temperature properties; Cause that graphite layers peels off, solving the main path that PC uses problem is to add the reduction that film for additive suppresses PC.Therefore, adding suitable film for additive, to improve the SEI film properties significant to improving the lithium ion battery performance.
So far, the film for additive of research is more, by its film forming principle; Can be divided into reduced form, (U.S.Patent 5 like vinylene carbonate (Vinylene carbonate, initialism are VC); 626,981), ethenylidene ethylene carbonate (VEC) (Electrochem.Solid-State Lett.8 (2005) A344), and response type; Like methyl benzol carbonate (methyl phenyl carbonate, initialism are MPC) (J.Electrochem.Soc.152 (2005) A1837), Li
2CO
3(J.Power Sources104 (2002) 132) etc.These research work all show, add suitable film for additive and can effectively improve the SEI film properties, help the performance of lithium ion battery performance.
Summary of the invention
Technical problem to be solved by this invention is: propose a kind of lithium-ion battery electrolytes, lithium ion battery, can effectively improve the performance of SEI film, help the performance of lithium ion battery performance.
Technical problem of the present invention solves through following technical scheme:
Said lithium-ion battery electrolytes comprises electric conducting lithium salt, carbonic ester mixed solvent and additive, and said additive comprises reduced form film for additive VC and response type film for additive MPC.
Preferably, be not more than 3wt.% at additive level described in the said lithium-ion battery electrolytes.
Preferably, in said lithium-ion battery electrolytes, the concentration of said VC is 0.1-2wt.%, and said MPC concentration is 0.1-2wt.%.
Further preferred, in said lithium-ion battery electrolytes, the concentration of said VC is 0.4-0.7wt.%, and MPC concentration is 0.3-0.5wt.%.
Preferably, said electric conducting lithium salt is LiBF
4, LiPF
6,, LiAsF
6, LiClO
4, LiCF
3SO
3, LiN (CF
3SO
3)
2, LiBOB, LiODFB, LiBF
3Cl and LiPF
4(C
2O
4) at least a.
Preferably; Said carbonic ester mixed solvent is propene carbonate (propylene carbonate; Initialism is PC) with following any two kinds or above mixing: ethylene carbonate (ethylene carbonate; Initialism is EC), dimethyl carbonate (dimethyl carbonate, initialism are DMC), diethyl carbonate (diethyl carbonate, initialism are DEC), methyl ethyl carbonate (Ethyl Methyl Carbonate; Initialism is EMC), wherein the weight content of PC is not less than 10%.
Preferably, in said lithium-ion battery electrolytes, said electric conducting lithium salt concentration is 0.8-1.2mol/L.
Preferably, said carbonic ester mixed solvent is a kind of in following three kinds of mixed solutions: 1: 1: 3 EC of volume ratio: PC: DMC, 1: 1: 1 PC of volume ratio: EMC: DMC, volume ratio 2: 1: 4: 3 EC: PC: DMC: EMC.
Preferably, said carbonic ester mixed solvent is volume ratio 2: 1: 4: 3 EC: PC: DMC: EMC mixed solution, said electric conducting lithium salt are LiPF6, and the concentration in said lithium-ion battery electrolytes is 1.0mol/L.
A kind of lithium ion battery comprises battery container, electrode group and electrolyte, and electrode group and electrolyte are sealed in the battery container, and the electrode group comprises positive pole, barrier film and negative pole, and said electrolyte adopts above-mentioned lithium-ion battery electrolytes.
The beneficial effect of the present invention and prior art contrast is: though the film that reduced form film-forming type additive forms is stable, general impedance is bigger than normal, though and favourable impedance, the not enough form compact and stable of film of reducing of film that reactive additive forms; Combination through reduced form additive vinylene carbonate and reactive additive methyl benzol carbonate is used; Two kinds of dissimilar film for additive act on simultaneously, have remedied the shortcoming of film forming alone, can produce the obvious synergistic effect; Have than the better effect of single additive; Can effectively improve silicon/carbon/graphite in lithium ion batteries negative terminal surface SEI film properties, make the film of formation fine and close more and stable, the lithium ion battery cycle performance is improved a lot.
Description of drawings
Accompanying drawing is embodiment 1 and 063048 prepared type LiFePO4 square battery cycle performance curve of comparative example.
Embodiment
The contrast accompanying drawing carries out detailed elaboration with the combination preferred embodiment to the present invention below.
In one embodiment, lithium-ion battery electrolytes comprises electric conducting lithium salt, carbonic ester mixed solvent and additive, and said additive comprises reduced form film for additive VC and response type film for additive MPC.Preferably, additive level is not more than 3wt.% in said lithium-ion battery electrolytes.
In certain embodiments, the concentration of the VC in the lithium-ion battery electrolytes is 0.1-2wt.%, and MPC concentration is 0.1-2wt.%.Further preferably, the concentration of VC is 0.4-0.7wt.%, and MPC concentration is 0.3-0.5wt.%.
In certain embodiments, electric conducting lithium salt is LiBF
4, LiPF
6,, LiAsF
6, LiClO
4, LiCF
3SO
3, LiN (CF
3SO
3)
2, LiBOB, LiODFB, LiBF
3Cl and LiPF
4(C
2O
4) at least a, further preferably, electric conducting lithium salt concentration is 0.8-1.2mol/L.
In further embodiments, the carbonic ester mixed solvent is PC and following any two kinds or above mixing: EC, DMC, DEC, EMC; Further preferably, wherein the weight content of PC is not less than 10%.Further preferably, the carbonic ester mixed solvent is a kind of in following three kinds of mixed solutions: 1: 1: 3 EC of volume ratio: PC: DMC, 1: 1: 1 PC of volume ratio: EMC: DMC, volume ratio 2: 1: 4: 3 EC: PC: DMC: EMC; Further preferably, the carbonic ester mixed solvent is volume ratio 2: 1: 4: 3 EC: PC: DMC: EMC mixed solution, electric conducting lithium salt are LiPF6, and concentration is 1.0mol/L.
In one embodiment; Lithium ion battery comprises battery container, electrode group and electrolyte, and electrode group and electrolyte are sealed in the battery container; The electrode group comprises positive pole, barrier film and negative pole, and said electrolyte adopts the lithium-ion battery electrolytes of above-mentioned arbitrary embodiment.Preferable several embodiment are below further described for example:
Embodiment 1
Preparation is consisted of 1.0M LiPF
6, 1: 1: 3 EC-PC-DMC of volume ratio, 0.5wt.%VC and 0.5wt.%MPC electrolyte; Inject 063048 type LiFePO4 square battery; Leave standstill and change into, adopt the CC/CV pattern then, promptly cycle performance of battery is tested with 0.5C charging, 1C discharge.300 times the circulation volume conservation rate is 92%.
The Comparative Examples 1 of embodiment 1: preparation is consisted of 1.0M LiPF
6, 1: 1: 3 EC-PC-DMC of volume ratio, 1.0wt.%VC electrolyte, inject 063048 type LiFePO4 square battery, leave standstill and change into, adopt the CC/CV pattern then, promptly cycle performance of battery is tested with 0.5C charging, 1C discharge.300 times the circulation volume conservation rate is 85%.
The Comparative Examples 2 of embodiment 1: preparation is consisted of 1.0M LiPF
6, 1: 1: 3 EC-PC-DMC of volume ratio, 1.0wt.%MPC electrolyte, inject 063048 type LiFePO4 square battery, leave standstill and change into, adopt the CC/CV pattern then, promptly cycle performance of battery is tested with 0.5C charging, 1C discharge.300 times the circulation volume conservation rate is 78%.
Embodiment 2
Preparation is consisted of 1.0M LiPF
6, 1: 1: 1 PC of volume ratio: the electrolyte of EMC: DMC, 0.5wt.%VC and 0.5wt.%MPC; Inject 063048 type LiFePO4 square battery; Leave standstill and change into, adopt the CC/CV pattern then, promptly cycle performance of battery is tested with 0.5C charging, 1C discharge.300 times the circulation volume conservation rate is 88%.
The Comparative Examples 1 of embodiment 2: preparation is consisted of 1.0M LiPF
6, 1: 1: 1 PC of volume ratio: the electrolyte of EMC: DMC, 1.0wt.%VC, inject 063048 type LiFePO4 square battery, leave standstill and change into, adopt the CC/CV pattern then, promptly cycle performance of battery is tested with 0.5C charging, 1C discharge.300 times the circulation volume conservation rate is 80%.
The Comparative Examples 2 of embodiment 2: preparation is consisted of 1.0M LiPF
6, 1: 1: 1 PC of volume ratio: the electrolyte of EMC: DMC, 1.0wt.%MPC, inject 063048 type LiFePO4 square battery, leave standstill and change into, adopt the CC/CV pattern then, promptly cycle performance of battery is tested with 0.5C charging, 1C discharge.300 times the circulation volume conservation rate is 73%.
Preparation is consisted of 1.0M LiPF
6, volume ratio 2: 1: 4: the electrolyte of 3 EC: PC: DMC: EMC, 0.5wt.%VC and 0.5wt.%MPC; Inject 063048 type LiFePO4 square battery; Leave standstill and change into, adopt the CC/CV pattern then, promptly cycle performance of battery is tested with 0.5C charging, 1C discharge.300 times the circulation volume conservation rate is 97%.
The Comparative Examples 1 of embodiment 3: preparation is consisted of 1.0M LiPF
6, volume ratio 2: 1: 4: the electrolyte of 3 EC: PC: DMC: EMC, 1.0wt.%VC, inject 063048 type LiFePO4 square battery, leave standstill and change into, adopt the CC/CV pattern then, promptly cycle performance of battery is tested with 0.5C charging, 1C discharge.300 times the circulation volume conservation rate is 88%.
The Comparative Examples of embodiment 3: 2: preparation is consisted of 1.0M LiPF
6, volume ratio 2: 1: 4: the electrolyte of 3 EC: PC: DMC: EMC, 1.0wt.%MPC, inject 063048 type LiFePO4 square battery, leave standstill and change into, adopt the CC/CV pattern then, promptly cycle performance of battery is tested with 0.5C charging, 1C discharge.300 times the circulation volume conservation rate is 82%.
Above content is to combine concrete preferred implementation to the further explain that the present invention did, and can not assert that practical implementation of the present invention is confined to these explanations.For the those of ordinary skill of technical field under the present invention, do not breaking away under the prerequisite of the present invention design, make some being equal to substitute or obvious modification, and performance or purposes are identical, all should be regarded as belonging to protection scope of the present invention.
Claims (10)
1. a lithium-ion battery electrolytes comprises electric conducting lithium salt, carbonic ester mixed solvent and additive, it is characterized in that: said additive comprises reduced form film for additive vinylene carbonate and response type film for additive methyl benzol carbonate simultaneously.
2. lithium-ion battery electrolytes according to claim 1 is characterized in that: be not more than 3wt.% at additive level described in the said lithium-ion battery electrolytes.
3. lithium-ion battery electrolytes according to claim 2 is characterized in that: in said lithium-ion battery electrolytes, the concentration of said vinylene carbonate is 0.1-2wt.%, and said methyl benzol carbonate concentration is 0.1-2wt.%.
4. lithium-ion battery electrolytes according to claim 3 is characterized in that: in said lithium-ion battery electrolytes, the concentration of said vinylene carbonate is 0.4-0.7wt.%, and methyl benzol carbonate concentration is 0.3-0.6wt.%.
5. according to any said lithium-ion battery electrolytes of claim 1-4, it is characterized in that: said electric conducting lithium salt is LiBF
4, LiPF
6,, LiAsF
6, LiClO
4, LiCF
3SO
3, LiN (CF
3SO
3)
2, LiBOB, LiODFB, LiBF
3Cl and LiPF
4(C
2O
4) at least a.
6. according to any said lithium-ion battery electrolytes of claim 1-4, it is characterized in that: said carbonic ester mixed solvent is propene carbonate and following any two kinds or above mixing: ethylene carbonate,, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate wherein the weight content of propene carbonate be not less than 10%.
7. according to the said lithium-ion battery electrolytes of claim 5, it is characterized in that: in said lithium-ion battery electrolytes, said electric conducting lithium salt concentration is 0.8-1.2mol/L.
8. according to the said lithium-ion battery electrolytes of claim 6, it is characterized in that: said carbonic ester mixed solvent is a kind of in following three kinds of mixed solutions: 1: 1: 3 ethylene carbonate of volume ratio: propene carbonate: dimethyl carbonate, 1: 1: 1 propene carbonate of volume ratio: methyl ethyl carbonate: dimethyl carbonate, volume ratio 2: 1: 4: 3 ethylene carbonate: propene carbonate: dimethyl carbonate: methyl ethyl carbonate.
9. according to any said lithium-ion battery electrolytes of claim 1-4; It is characterized in that: said carbonic ester mixed solvent is volume ratio 2: 1: 4: 3 ethylene carbonate: propene carbonate: dimethyl carbonate: the methyl ethyl carbonate mixed solution; Said electric conducting lithium salt is LiPF6, and the concentration in said lithium-ion battery electrolytes is 1.0mol/L.
10. lithium ion battery; Comprise battery container, electrode group and electrolyte; Electrode group and electrolyte are sealed in the battery container, and the electrode group comprises positive pole, barrier film and negative pole, it is characterized in that: said electrolyte adopts the arbitrary described lithium-ion battery electrolytes of claim 1 to 9.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102709590A (en) * | 2012-03-01 | 2012-10-03 | 华瑞(新乡)化工有限公司 | Novel lithium ion battery and electrolyte |
| CN106329001A (en) * | 2016-11-29 | 2017-01-11 | 河南省法恩莱特新能源科技有限公司 | Low-temperature high-voltage lithium-ion battery electrolyte |
| CN111224160A (en) * | 2018-11-26 | 2020-06-02 | 中国科学院大连化学物理研究所 | Electrolyte for lithium ion battery and application thereof |
| CN113410522A (en) * | 2021-06-18 | 2021-09-17 | 山东省智能光电新能源研究院 | Method for improving stability of SEI (solid electrolyte interface) film of lithium ion battery |
| CN114583273A (en) * | 2022-03-02 | 2022-06-03 | 香河昆仑新能源材料股份有限公司 | Electrolyte containing benzyl carbonate and battery composed of electrolyte |
| CN114597489A (en) * | 2022-03-22 | 2022-06-07 | 香河昆仑新能源材料股份有限公司 | Electrolyte containing fluorobenzene carbonate and battery composed of electrolyte |
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| CN101960662A (en) * | 2008-02-29 | 2011-01-26 | 三菱化学株式会社 | Nonaqueous electrolyte solution and nonaqueous electrolyte battery |
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| CN101960662A (en) * | 2008-02-29 | 2011-01-26 | 三菱化学株式会社 | Nonaqueous electrolyte solution and nonaqueous electrolyte battery |
Non-Patent Citations (2)
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|---|
| JYH-TSUNG LEE ET.AL: "Effects of Aromatic Esters as Propylene Carbonate-Based Electrolyte Additives in Lithium-Ion Batteries", 《JOURNAL OF THE ELECTROCHEMICAL SOCIETY》 * |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102709590A (en) * | 2012-03-01 | 2012-10-03 | 华瑞(新乡)化工有限公司 | Novel lithium ion battery and electrolyte |
| CN106329001A (en) * | 2016-11-29 | 2017-01-11 | 河南省法恩莱特新能源科技有限公司 | Low-temperature high-voltage lithium-ion battery electrolyte |
| CN111224160A (en) * | 2018-11-26 | 2020-06-02 | 中国科学院大连化学物理研究所 | Electrolyte for lithium ion battery and application thereof |
| CN113410522A (en) * | 2021-06-18 | 2021-09-17 | 山东省智能光电新能源研究院 | Method for improving stability of SEI (solid electrolyte interface) film of lithium ion battery |
| CN114583273A (en) * | 2022-03-02 | 2022-06-03 | 香河昆仑新能源材料股份有限公司 | Electrolyte containing benzyl carbonate and battery composed of electrolyte |
| CN114597489A (en) * | 2022-03-22 | 2022-06-07 | 香河昆仑新能源材料股份有限公司 | Electrolyte containing fluorobenzene carbonate and battery composed of electrolyte |
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