Electrolyte, lithium battery and lithium metal battery including the same, and method of preparing the electrolyte

Patent metadata

Field	Value
Publication number	US-2016013515-A1
Application number	US-201514799102-A
Country	US
Kind code	A1
Filing date	Jul 14, 2015
Priority date	Jul 14, 2014
Publication date	Jan 14, 2016
Grant date	—

Abstract

An electrolyte including a block copolymer having a first domain and a second domain covalently linked to the first domain, an ionic liquid, an oligomer, an inorganic particle, and a lithium salt, wherein the first domain includes an ion conductive polymer block, and the second domain includes a non-conducting polymer block.

First claim

What is claimed is:

1 . An electrolyte comprising:
a block copolymer comprising a first domain and a second domain covalently linked to the first domain; an ionic liquid; an oligomer; an inorganic particle; and a lithium salt, wherein the first domain comprises an ion conductive polymer block, and the second domain comprises a non-conducting polymer block.

2 . The electrolyte of claim 1 , wherein a size D 1 of the first domain calculated according to Equation 1 is greater than a size D 2 of the second domain, calculated according to Equation 1:
D 1 =2π/ q 1   Equation 1
wherein q 1 is a first domain scattering vector determined by transmission electron microscopy small angle X-ray scattering
D 2 =2π/ q 2   Equation 2.

wherein q 2 is a second domain scattering vector determined by transmission electron microscopy small angle X-ray scattering.

3 . The electrolyte of claim 1 , wherein a size D 1 of the first domain is in a range of about 22 nanometers to about 100 nanometers.

4 . The electrolyte of claim 1 , wherein a number average molecular weight Mn of the ion conductive polymer block comprised in the first domain is 10,000 Daltons or greater.

5 . The electrolyte of claim 1 , wherein a number average molecular weight of the non-conducting polymer block comprised in the second domain is 10,000 Daltons or greater.

6 . The electrolyte of claim 1 , wherein an amount of the non-conducting polymer block comprised in the second domain is in a range of about 20 percent by weight to about 45 percent by weight based on a total weight of the block copolymer.

7 . The electrolyte of claim 1 , wherein the block copolymer comprises a linear block copolymer, a branched block copolymer, or a combination thereof.

8 . The electrolyte of claim 1 , wherein the block copolymer comprises at least one of a linear diblock copolymer A-B and a linear triblock copolymer A-B-A′;
wherein the blocks A and A′ are the same or different and are each independently an ion conductive polymer block selected from a polyethylene oxide block, a polysiloxane block, a polypropylene oxide block, a polyethylene oxide-grafted polymethylmethacrylate block, a polypropylene oxide-grafted polymethylmethacrylate block, a poly(dialkylsiloxane-co-ethylene oxide) block, a poly(dialkylsiloxane-co-propylene oxide) block, and a polysiloxane-grafted PMMA block; and
wherein the block B is a non-conducting polymer block selected from a polystyrene block, a PMMA block, a polyvinylpyridine block, a polyimide block, a polyethylene block, a polypropylene block, a polyvinylidene fluoride block, a polyacrylonitrile block, and a polydimethylsiloxane block.

9 . The electrolyte of claim 1 , wherein the ionic liquid comprises at least one cation selected from a pyrrolidinium cation, a pyridinium cation, an imidazolium cation, a piperidinium cation, and an ammonium cation, an alkylammonium cation, and at least one anion selected from bis(trifluoromethylsulfonyl)imide, bromide, chloride, dicyanamide, hexafluorophosphate, phosphate, sulfate, iodide, sulfonate, nitrate, tetrafluoroborate, thiocyanate, and triflate.

10 . The electrolyte of claim 9 , wherein an ionic liquid to lithium ion molar ratio is in a range of about 0.1 to about 2.0.

11 . The electrolyte of claim 1 , wherein the oligomer comprises an ethylene oxide repeating unit and has a number average molecular weight of about 200 Daltons to about 2,000 Daltons.

12 . The electrolyte of claim 1 , wherein a content of the oligomer is in a range of about 5 percent by weight to about 50 percent by weight based on a total weight of the electrolyte.

13 . The electrolyte of claim 1 ,
wherein the inorganic particle is dispersible in the first domain and wherein the inorganic particle comprises at least one nanoparticle selected from SiO 2 , TiO 2 , ZnO, Al 2 O 3 , BaTiO 3 , and a metal-organic framework.

14 . The electrolyte of claim 1 , wherein a content of the inorganic particle is in a range of about 1 percent by weight to about 40 percent by weight based on a total weight of the electrolyte.

15 . The electrolyte of claim 1 , wherein the lithium salt comprises at least one selected from lithium trifluoromethanesulfonimide, LiBF 4 , LiPF 6 , lithium bis[1,2-oxalato 2+O,O′]borate, and LiClO 4 .

16 . The electrolyte of claim 1 , further comprising an organic solvent, a homopolymer, or a combination thereof.

17 . The electrolyte of claim 1 , wherein the electrolyte is a gel phase layer or a solid phase layer.

18 . The electrolyte of claim 17 , wherein the gel phase layer or the solid phase layer has a thickness equal to or less than 100 micrometers.

19 . The electrolyte of claim 1 , wherein the electrolyte has an ion conductivity of 1×10 −4 Siemens per centimeter or greater at 25° C.

20 . The electrolyte of claim 1 , wherein the electrolyte has a Young's modulus of 1.0 mega Pascals or greater.

21 . A lithium battery comprising:
a positive electrode comprising a positive active material; a negative electrode comprising a negative active material; and an electrolyte interposed between the positive electrode and the negative electrode, wherein the electrolyte comprises the electrolyte according to claim 1 .

22 . The lithium battery of claim 21 , wherein the electrolyte is a gel phase layer or a solid phase layer.

23 . The lithium battery of claim 22 , wherein the layer is a single layer or a plurality of layers.

24 . The lithium battery of claim 21 , further comprising a protective layer disposed on and at least partially contacting a surface of the negative electrode or disposed separately from and having no contact with the negative electrode,
wherein the protective layer is a single layer or a plurality of layers.

25 . The lithium battery of claim 24 , wherein the protective layer comprises a block copolymer and a lithium salt,
wherein the block copolymer comprises a first domain and a second domain covalently linked to the first domain, and wherein the first domain comprises an ion conductive polymer block, and the second domain comprises a non-conducting polymer block.

26 . The lithium battery of claim 24 , wherein the protective layer is a gel phase layer or a solid phase layer.

27 . The lithium battery of claim 22 , wherein the gel phase layer and the solid phase layer has a thickness equal to or less than 100 micrometers.

28 . The lithium battery of claim 21 , wherein the lithium battery has an operation voltage of 4.5 Volts±0.5 Volts.

29 . A lithium metal battery comprising:
a positive electrode comprising a positive active material; a negative electrode comprising a lithium metal or lithium alloy as a negative active material; and a separator interposed between the positive electrode and the negative electrode, wherein the separator comprises an electrolyte according to claim 1 .

30 . The lithium metal battery of claim 29 , further comprising a protective layer disposed on and at least partially contacting a surface of the negative electrode or disposed separately from and having no contact with the negative electrode,
wherein the protective layer is formed as a single layer or a plurality of layers.

31 . The lithium metal battery of claim 30 , wherein the protective layer comprises a blo

Assignees

• Samsung Electronics Co Ltd

Inventors

• Lee Yonggun
• Yang Yooseong
• Lee Jenam
• Choi Hongsoo

Classifications

• H01M50/414

  Synthetic resins, e.g. thermoplastics or thermosetting resins · CPC title

• H01M2/1673

  Electricity · mapped topic

• H01M2300/0025

  Organic electrolyte · CPC title

• H01M10/0565 Primary

  Polymeric materials, e.g. gel-type or solid-type · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title