Electrolyte and negative electrode structure
AssigneeGM Global Technology Operations LLC
InventorsLi Yang, Mei Cai, Fang Dai, Qiangfeng Xiao, Mark W. Verbrugge
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Abstract
An example electrolyte includes a solvent, a lithium salt, and an additive selected from the group consisting of a silane with at least one Si—H group; a fluorinated methoxysilane; a fluorinated chlorosilane; and combinations thereof. The electrolyte may be used in a method for making a solid electrolyte interface (SEI) layer on a surface of a lithium electrode. A negative electrode structure may be formed from the method.
Claims14
An electrolyte for forming a protective solid electrolyte interface layer on a surface of an electrode for an electrochemical cell, the electrolyte comprising:
- a solvent;
- a lithium salt;
- and
- an additive selected from the group consisting of a silane with at least one Si—H group;
- a fluorinated methoxysilane;
- a fluorinated chlorosilane;
- and combinations thereof,
- wherein the silane with at least one Si—H group is selected from the group consisting of H—Si((CH2)xCH3)2—R-Anion− Li+ and H—Si((CH2)xCH3)2—O—R-Anion− Li+, wherein x ranges from 0 to 2, R is any element or organic group, and the anion is selected from the group consisting of PF5−, BF3−, bis(trifluoromethane sulfonyl)imide (TFSI−), bis(fluorosulfonyl)imide (FSI−), and fluorine-malonato(difluoro)borate ((F)MDFB−),
- wherein the fluorinated chlorosilane is represented by a formula (CH3)xSiCly—(CH2)m—(CF2)n—CF3, wherein x is 1 and y is 2 or x is 2 and y is 1, m ranges from 0 to 2, and n ranges from 1 to 20,
- wherein the fluorinated methoxysilane is selected from the group consisting of:
A negative electrode structure, comprising:
- a negative electrode including lithium as an active material;
- and
- a solid electrolyte interface (SEI) layer formed on a surface of the negative electrode, the SEI layer formed from a silane with at least one Si—H group;
- a fluorinated methoxysilane;
- a fluorinated chlorosilane;
- and combinations thereof,
- wherein the silane with at least one Si—H group is selected from the group consisting of H—Si((CH2)xCH3)2—R-Anion− Li+ and H—Si((CH2)xCH3)2—O—R-Anion− Li+, wherein x ranges from 0 to 2, R is any element or organic group, and the anion is selected from the group consisting of PF5−, BF3−, bis(trifluoromethane sulfonyl)imide (TFSI−), bis(fluorosulfonyl)imide (FSI−), and fluorine-malonato(difluoro)borate ((F)MDFB−),
- wherein the fluorinated chlorosilane is represented by a formula (CH3)xSiCly—(CH2)m—(CF2)n—CF3, where x is 1 and y is 2 or x is 2 and y is 1, m ranges from 0 to 2, and n ranges from 1 to 20, and
- wherein the fluorinated methoxysilane is selected from the group consisting of:
A method for making a solid electrolyte interface (SEI) layer on a surface of a lithium electrode, the method comprising:
- exposing the lithium electrode to an electrolyte including:
- a solvent;
- a lithium salt;
- and
- an additive selected from the group consisting of a silane with at least one Si—H group;
- a fluorinated methoxysilane;
- a fluorinated chlorosilane;
- and combinations thereof,
- wherein the silane with at least one Si—H group is selected from the group consisting of H—Si((CH2)xCH3)2—R-Anion− Li+ and H—Si((CH2)xCH3)2—O—R-Anion− Li+, wherein x ranges from 0 to 2, R is any element or organic group, and the anion is selected from the group consisting of PF5−, BF3−, bis(trifluoromethane sulfonyl)imide (TFSI−), bis(fluorosulfonyl)imide (FSI−), and fluorine-malonato(difluoro)borate ((F)MDFB−),
- wherein the fluorinated chlorosilane is represented by a formula (CH3)xSiCly—(CH2)m—(CF2)n—CF3, wherein x is 1 and y is 2 or x is 2 and y is 1, m ranges from 0 to 2, and n ranges from 1 to 20, and
- wherein the fluorinated methoxysilane is selected from the group consisting of:
Dependencies are inferred from the claim text.