Electrolyte for lithium-metal battery having improved stability

Patent metadata

Field	Value
Publication number	US-12132172-B2
Application number	US-202117538866-A
Country	US
Kind code	B2
Filing date	Nov 30, 2021
Priority date	Dec 11, 2020
Publication date	Oct 29, 2024
Grant date	Oct 29, 2024

Abstract

An electrolyte capable of lip roving the stability of a lithium-metal battery is provided. The electrolyte includes an organic solvent, a cosolvent, which is different from the organic solvent and includes a fluorine-based compound, and an additive having a lower lowest unoccupied molecular orbital (LUMO) value than the organic solvent.

First claim

What is claimed is:

1. An electrolyte, comprising:
an organic solvent;
a cosolvent, wherein the cosolvent is different from the organic solvent and comprises a fluorine-based compound; and
an additive having a lower lowest unoccupied molecular orbital (LUMO) value than the organic solvent,
wherein the additive comprises difluorophosphate (LiPO 2 F 2 ),
wherein the organic solvent comprises 1,2-dimethoxyethane,
wherein the cosolvent comprises 1,1,2,2-tetraflouroethyl-1H, 1H,5H-octafluoropentyl ether (TFOFE), and
wherein a volume ratio of the organic solvent and the cosolvent is 5:5 to 9:1.

2. The electrolyte of claim 1 , wherein the cosolvent has a lower HOMO (highest occupied molecular orbital) value than the organic solvent.

3. The electrolyte of claim 1 , wherein a HOMO value of the cosolvent satisfies −11 eV≤HOMO≤−7.5 eV.

4. The electrolyte of claim 1 , wherein the additive has a LUMO value of 1.5 eV or less.

5. The electrolyte of claim 1 , wherein an amount of the additive is 0.1 wt % to 10 wt %.

6. The electrolyte of claim 1 , further comprising a lithium salt, comprising at least one selected from the group consisting of LiFSI, LiTFSI, LiPF 6 , LiBF 4 , LiSbF 6 , LiAsF 6 , LiC 4 F 9 SO 3 , LiClO 4 , LiAlO 2 , LiAlCl 4 , LiCl, LiI, and combinations thereof.

7. The electrolyte of claim 6 , wherein a concentration of the lithium salt is 1.5 mol/L to 3 mol/L.

8. A lithium-metal battery, comprising:
a cathode;
an anode comprising lithium metal;
a separator; and
the electrolyte of claim 1 .

9. The lithium-metal battery of claim 8 , further comprising a passivation layer on the anode, in which the passivation layer comprises a reduced decomposition product of an additive.

10. The lithium-metal battery of claim 9 , wherein the reduced decomposition product comprises lithium fluoride (LiF).

Assignees

• Hyundai Motor Co Ltd
• Kia Corp
• Ulsan National Institute Of Science And Tech

Inventors

• Lee Ji Yong
• Song Jong Chan
• Choi Nam Soon
• Lee Won Joon
• Kim Sae Hun
• Lee Min Young
• Ahn Young Joon

Classifications

• H01M10/0567

  characterised by the additives · CPC title

• H01M2300/0042

  Four or more solvents · CPC title

• H01M2300/0057

  Chlorides · CPC title

• H01M2300/0037

  Mixture of solvents · CPC title

• H01M10/052

  Li-accumulators · CPC title