Electrolyte and secondary battery
View Patent ↗A secondary battery capable of achieving superior cycle characteristics, superior storage characteristics, and superior swollenness characteristics is provided. The secondary battery includes a cathode, an anode, and an electrolyte containing a solvent and an electrolyte salt. The solvent contains halogenated cyclic ester carbonate. The halogenated cyclic ester carbonate is a cyclic compound that has one or more fluorine groups, one or more fluorinated alkyl groups, and a carbonyl group.
1. A secondary battery comprising:
a cathode;
an anode; and
an electrolyte containing a solvent and an electrolyte salt,
wherein the solvent contains a first halogenated cyclic ester carbonate shown in Formula 2:
where R5to R7are a hydrogen group, a halogen group, or an alkyl group, and at least one thereof is a halogen group, wherein R5 to R7 comprise one or two carbons in the alkyl group,
wherein the solvent contains a second halogenated cyclic ester carbonate shown in Formula 7, the second halogenated cyclic ester carbonate being different than the first halogenated cyclic ester carbonate:
where R27 to R30 are a hydrogen group, a halogen group, an alkyl group, or a halogenated alkyl group, and at least one of R27 to R30is the halogen group or the halogenated alkyl group, wherein R27 to R30 comprise one or two carbons in the alkyl group or the halogenated alkyl group, wherein the content of the first halogenated cyclic ester carbonate and the second halogenated cyclic ester carbonate in the solvent is from 0.01 wt % to 50% wt %, and
wherein the solvent contains unsaturated carbon bond cyclic ester carbonates, the unsaturated carbon bond cyclic ester carbonates being catechol carbonate.
2. The secondary battery according to claim 1 , wherein the first halogenated cyclic ester carbonate shown in the Formula 2 is a compound shown in Formula 1-1 to Formula 1-9
3. The secondary battery according to claim 2 , wherein the first halogenated cyclic ester carbonate shown in the Formula 2 is the compound shown in the Formula 1-1 or the compound shown in the Formula 1-2.
4. The secondary battery according to claim 1 , wherein the anode contains a carbon material, lithium metal (Li), or a material that is able to insert and extract an electrode reactant and contains as an element at least one of a metal element and a metalloid element as an anode active material.
5. The secondary battery according to claim 1 , wherein the anode contains a material that contains at least one of silicon (Si) and tin (Sn) as an anode active material.
6. The secondary battery according to claim 5 , wherein the material that contains as an element at least one of silicon and tin is a simple substance of silicon or a SnCoC-containing material containing tin, cobalt (Co), and carbon (C) as an element, and
in the SnCoC-containing material, a content of carbon is from 9.9 wt % to 29.7 wt % both inclusive, a ratio of tin and cobalt (Co/(Sn+Co)) is from 20 wt % to 70 wt % both inclusive, and a half bandwidth of a diffraction peak obtained by X-ray diffraction is 1.0 deg or more.
7. The secondary battery according to claim 1 , wherein the anode contains a carbon material as an anode active material, and a content of the first halogenated cyclic ester carbonate in the solvent is from 0.01 wt % to 10 wt % both inclusive.
8. The secondary battery according to claim 1 , wherein the electrolyte salt contains at least one of lithium hexafluorophosphate (LiPF 6 ), lithium tetrafluoroborate (LiBF 4 ), lithium perchlorate (LiCIO 4 ), lithium hexafluoroarsenate (LiAsF 6 ), and compounds shown in Formula 8 to Formula 13:
where X31 is a Group 1 element or a Group 2 element in the long period periodic table or aluminum (Al); M31 is a transition metal element, a Group 13 element, a Group 14 element, or a Group 15 element in the long period periodic table; R31 is a halogen group; Y31 is —(O═)C—R32-C(═O)—, —(O═)C—C(R33)2-, or —(O═)C—C(═O)—; R32 is an alkylene group, a halogenated alkylene group, an arylene group, or a halogenated arylene group; R33 is an alkyl group, a halogenated alkyl group, an aryl group, or a halogenated aryl group; a3 is one of integer numbers 1 to 4; b3 is 0, 2, or 4; and c3, d3, m3,and n3 are one of integer numbers 1 to 3;
where X41 is a Group 1 element or a Group 2 element in the long period periodic table; M41 is the transition metal element, or a Group 13 element, a Group 14 element, or a Group 15 element in the long period periodic table; Y41 is —(O═)C—(C(R41) 2 ) b4 -C(═O)—, —(R43) 2 C—(C(R42) 2 ) c4 -C(═O)—, —(R43) 2 C—(C(R42) 2 ) c4 -C(R43) 2 -, —(R43) 2 C—(C(R42) 2 ) c4 -S(═O) 2 —, —(O═) 2 S—(C(R42) 2 ) d4 -S(═O) 2 —, or —(O═)C—(C(R42) 2 ) d4 -S(═O) 2 —; R41 and R43 are a hydrogen group, an alkyl group, a halogen group, or a halogenated alkyl group; at least one of R41 and R43 is respectively the halogen group or the halogenated alkyl group; R42 is a hydrogen group, an alkyl group, a halogen group, or a halogenated alkyl group; a4, e4, and n4 are 1 or 2; b4 and d4 are one of integer numbers 1 to 4; c4 is one of integer numbers 0 to 4; and f4 and m4 are one of integer numbers 1 to 3;
where X51 is a Group 1 element or a Group 2 element in the long period periodic table; M51 is the transition metal element, or a Group 13 element, a Group 14 element, or a Group 15 element in the long period periodic table;
Rf is a fluorinated alkyl group with the carbon number from 1 to 10 both inclusive or a fluorinated aryl group with the carbon number from 1 to 10 both inclusive;
Y51 is —(O═)C—(C(R51) 2 ) d5 -C(═O)—, —(R52) 2 C—(C(R51) 2 ) d5 -C(═O)—, —(R52) 2 C—(C(R51) 2 ) d5 -C(R52) 2 -, —(R52) 2 C—(C(R51) 2 ) d5 -S(═O) 2 —, —(O═) 2 S—(C(R51) 2 ) e5 -S(═O) 2 —, or —(O═)C—(C(R51) 2 ) e5 -S(═O) 2 —; R51 is a hydrogen group, an alkyl group, a halogen group, or a halogenated alkyl group; R52 is a hydrogen group, an alkyl group, a halogen group, or a halogenated alkyl group, and at least one thereof is the halogen group or the halogenated alkyl group; a5, f5, and n5 are 1 or 2; b5, c5, and e5 are one of integer numbers 1 to 4; d5 is one of integer numbers 0 to 4; and g5 and m5 are one of integer numbers 1 to 3;
Formula 11
LiN(C m F 2m+1 SO 2 )(C n F 2n+1 SO 2 ) (11)
where m and n are an integer number of 1 or more;
where R61 is a straight chain or branched perfluoro alkylene group with the carbon number from 2 to 4 both inclusive; and
Formula 13
LiC(C p F 2p+1 SO 2 )(C q F 2q+1 SO 2 )(C r F 2r+1 SO 2 ) (13)
where p, q, and r are an integer number of 1 or more.
9. The secondary battery according to claim 1 , wherein the anode has an anode active material layer on an anode current collector, and the anode active material layer is formed by at least one of vapor-phase deposition method, liquid-phase deposition method, and firing method.
10. The secondary battery according to claim 1 , wherein the anode has an anode active material layer containing a plurality of anode active material particles, and the anode active material layer includes an oxide-containing film that covers a surface of the anode active material particles.
11. The secondary battery according to claim 10 , wherein the oxide-containing film contains at least one of an oxide of silicon, an oxide of germanium (Ge), and an oxide of tin.
12. The secondary battery according to claim 1 , wherein the anode has an anode active material layer containing a plurality of anode active material particles, and the anode active material layer contains a metal material containing a metal element not being alloyed with an electrode reactant as an element in a gap inside the anode active material layer.
13. The secondary battery according to claim 12 , wherein the metal element is at least one of iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), and copper (Cu).
14. The secondary battery according to claim 1 , wherein the cathode and the anode are able to insert and extract lithium ion as an electrode reactant.
15. The secondary battery according to claim 1 , wherein the second halogenated cyclic ester carbonate is 4-fluoro-1,3-dioxolane-2-one or 4,5-difluoro-1,3-dioxolane-2-one.
16. An electrolyte containing a solvent and an electrolyte salt, wherein the solvent contains a first halogenated cyclic ester carbonate shown in Formula 2:
where R5 to R7are a hydrogen group, a halogen group, or an alkyl group, and at least one thereof is a halogen group, wherein R5 to R7 comprise one or two carbons in the alkyl group,
wherein the solvent contains a second halogenated cyclic ester carbonate shown in Formula 7, the second halogenated cyclic ester carbonate being different than the first halogenated cyclic ester carbonate:
where R27 to R30 are a hydrogen group, a halogen group, an alkyl group, or a halogenated alkyl group, and at least one of R27 to R30 is the halogen group or the halogenated alkyl group, wherein R27 to R30 comprise one or two carbons in the alkyl group or the halogenated alkyl group, wherein the content of the first halogenated cyclic ester carbonate and the second halogenated cyclic ester carbonate in the solvent is from 0.01 wt % to 50% wt %, and
wherein the solvent contains unsaturated carbon bond cyclic ester carbonates, the unsaturated carbon bond cyclic ester carbonates being catechol carbonate.
17. The electrolyte according to claim 16 is used for a secondary battery.