Lithium metal secondary battery using lithium metal as negative electrode active material

Patent metadata

Field	Value
Publication number	US-10840538-B2
Application number	US-201815980216-A
Country	US
Kind code	B2
Filing date	May 15, 2018
Priority date	May 29, 2017
Publication date	Nov 17, 2020
Grant date	Nov 17, 2020

Abstract

A lithium metal secondary battery includes a positive electrode, a negative electrode, a solid electrolyte, and a soft electrolyte. The negative electrode includes a negative electrode current collector having at least one hole, in which lithium metal is deposited in a charged state. The solid electrolyte is disposed on the surface, which face negative electrode current collector, of the positive electrode. The soft electrolyte fills the space between the negative electrode current collector and solid electrolyte and entering into the at least one hole. The solid and soft electrolytes have lithium ion conductivity.

First claim

What is claimed is:

1. A lithium metal secondary battery comprising:
a first positive electrode;
a negative electrode including a negative electrode current collector having a plurality of holes, in each of which lithium metal is deposited in a charged state;
a first solid electrolyte disposed on a surface, which faces the negative electrode current collector, of the first positive electrode, the first solid electrolyte having lithium ion conductivity; and
a soft electrolyte filling a space between the negative electrode current collector and the first solid electrolyte and entering into the plurality of holes, the soft electrolyte being a polymer electrolyte or a gel electrolyte having lithium ion conductivity, wherein
the deposited lithium metal is in direct contact with the polymer electrolyte or the gel electrolyte in each of the plurality of holes.

2. The lithium metal secondary battery according to claim 1 , wherein
the plurality of holes are a plurality of through holes passing through the negative electrode current collector.

3. The lithium metal secondary battery according to claim 1 , wherein
the plurality of holes are a plurality of bottomed holes provided on a surface, which faces the first positive electrode, of the negative electrode current collector.

4. The lithium metal secondary battery according to claim 1 , wherein
a soft electrolyte fills each of the plurality of holes with a clearance, in which the lithium metal is deposited in a charged state, and
the clearance is left in a discharged state as a space not filled with the soft electrolyte.

5. The lithium metal secondary battery according to claim 1 , wherein
the first solid electrolyte is an inorganic solid electrolyte.

6. The lithium metal secondary battery according to claim 5 , wherein
the inorganic solid electrolyte is a molded electrolyte or a sintered electrolyte.

7. The lithium metal secondary battery according to claim 5 , wherein
the inorganic solid electrolyte has a garnet structure.

8. The lithium metal secondary battery according to claim 7 , wherein
the inorganic solid electrolyte is a composite oxide containing Li, La, and Zr.

9. The lithium metal secondary battery according to claim 8 , wherein
the composite oxide further contains at least one selected from the group consisting of Al, Mg, Ca, Sr, Ba, Ta, Nb, and Yb.

10. The lithium metal secondary battery according to claim 1 , wherein
a percentage of a total volume of the soft electrolyte filling the plurality of holes to a total volume of the plurality of holes is 3% or more and 90% or less.

11. The lithium metal secondary battery according to claim 10 , wherein
the percentage is 80% or less.

12. The lithium metal secondary battery according to claim 1 , further comprising:
a second positive electrode disposed opposite to the first positive electrode across the soft electrolyte and the negative electrode; and
a second solid electrolyte on a surface, which faces the negative electrode current collector, of the second positive electrode, the second solid electrolyte having lithium ion conductivity, wherein
the soft electrolyte further fills a space between the negative electrode current collector and the second solid electrolyte.

13. The lithium metal secondary battery according to claim 1 , wherein
a thickness of the negative electrode current collector is 6 μm or more and 150 μm or less.

14. The lithium metal secondary battery according to claim 1 , wherein
an average diameter of the plurality of holes is 5 μm or more.

15. The lithium metal secondary battery according to claim 1 , wherein
the negative electrode current collector is an only component of the negative electrode.

16. A lithium metal secondary battery comprising:
a positive electrode;
a negative electrode including a negative electrode current collector having a plurality of protrusions, around each of which lithium metal is deposited in a charged state;
a solid electrolyte disposed on a surface, which faces the negative electrode current collector, of the positive electrode, the solid electrolyte having lithium ion conductivity; and
a soft electrolyte filling a space between the negative electrode current collector and the solid electrolyte and around the plurality of protrusions, the soft electrolyte being a polymer electrolyte or a gel electrolyte having lithium ion conductivity, wherein
the deposited lithium metal is in direct contact with the polymer electrolyte or the gel electrolyte around a side wall of each of the plurality of protrusions.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Sakamoto Junichi
• Kano Akira
• Matsui Tooru
• Asano Kazuko
• Kanamura Kiyoshi

Classifications

• H01M50/417

  Polyolefins · CPC title

• H01M50/489

  Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties · CPC title

• H01M4/82

  Multi-step processes for manufacturing carriers for lead-acid accumulators · CPC title

• H01M4/80

  Porous plates, e.g. sintered carriers · CPC title

• H01M4/72

  Grids · CPC title