Protective film for lithium electrode, and lithium electrode and lithium secondary battery comprising same

Patent metadata

Field	Value
Publication number	US-2018294513-A1
Application number	US-201715766106-A
Country	US
Kind code	A1
Filing date	Apr 4, 2017
Priority date	Apr 14, 2016
Publication date	Oct 11, 2018
Grant date	—

Abstract

The present invention relates to a passivation layer for a lithium electrode, and a lithium electrode and a lithium secondary battery including the same, and in particular, to a lithium electrode capable of enhancing battery performance by securing a sufficient level of strength to suppress lithium dendrite growth through forming a passivation layer in an electrode including lithium, and through forming the passivation layer in a fibrous network structure, and a lithium secondary battery including the same.

First claim

1 . A passivation layer for a lithium electrode having a fibrous network structure including a cellulose-based fibrous filler.

2 . The passivation layer for a lithium electrode of claim 1 , which has a thickness of 10 nm to 10 μm.

3 . The passivation layer for a lithium electrode of claim 1 , wherein the fibrous filler further includes any one or more of an organic filler and an inorganic filler.

4 . The passivation layer for a lithium electrode of claim 3 , wherein the organic filler includes one types selected from the group consisting of acryl-based fibers, amide-based fibers, olefin-based fibers, ester-based fibers, urethane-based fibers, styrene-based fibers, imide-based fibers and combinations thereof

5 . The passivation layer for a lithium electrode of claim 3 , wherein the inorganic filler includes one type selected from the group consisting of alumina fibers, aluminosilicate fibers, silica fibers, aluminosilicate, aluminoborosilicate, mullite, magnesium silicate fibers, calcium magnesium silicate fibers and combinations thereof.

6 . The passivation layer for a lithium electrode of claim 1 , wherein the fibrous filler has an average fiber diameter of 1 nm to 10 μm and an average fiber length of 100 nm to 500 μm.

7 . The passivation layer for a lithium electrode of claim 1 , further comprising one type selected from the group consisting of an ion conductive polymer, a lithium salt, a particulate filler and a mixture thereof.

8 . The passivation layer for a lithium electrode of claim 7 , wherein the ion conductive polymer forms a network structure in the passivation layer through crosslinking.

9 . The passivation layer for a lithium electrode of claim 7 , wherein the ion conductive polymer includes one type selected from the group consisting of polyethylene oxide, polypropylene oxide, polydimethylsiloxane, polyacrylonitrile, polymethyl (meth)acrylate, polyvinyl chloride, polyvinylidene fluoride, polyvinylidene fluoride-co-hexafluoropropylene, polyethyleneimine, polyphenylene terephthalamide, polymethoxypolyethylene glycol (meth)acrylate, poly-2-methoxyethyl glycidyl ether and combinations thereof.

10 . The passivation layer for a lithium electrode of claim 7 , wherein the ion conductive polymer is used in greater than 0 parts by weight and less than or equal to 5000 parts by weight with respect to 100 parts by weight of the fibrous filler.

11 . The passivation layer for a lithium electrode of claim 7 , wherein the lithium salt includes one type selected from the group consisting of LiCl, LiBr, LiI, LiClO 4 , LiBF 4 , LiCF 3 SO 3 , LiCF 3 CO 2 , LiAsF 6 , LiSbF 6 , LiAlCl 4 , CH 3 SO 3 Li, CF 3 SO 3 Li, LiSCN, LiC(CF 3 SO 2 ) 3 , (CF 3 SO 2 ) 2 NLi, (FSO 2 ) 2 NLi, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenylborate, lithium imide and combinations thereof

12 . The passivation layer for a lithium electrode of claim 7 , which uses, when using the ion conductive polymer and the lithium salt, the lithium salt in 1 parts by weight to 100 parts by weight with respect to 100 parts by weight of the ion conductive polymer.

13 . The passivation layer for a lithium electrode of claim 7 , wherein the particulate filler has an average particle diameter of 1 nm to 5 μm.

14 . The passivation layer for a lithium electrode of claim 7 , wherein the particulate filler includes one type selected from the group consisting of organic particles, inorganic particles and combinations thereof.

15 . The passivation layer for a lithium electrode of claim 14 , wherein the organic particles include one type selected from the group consisting of polyethylene, polypropylene, poly(meth)acrylate, polymethyl (meth)acrylate, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), perfluoroalkyl polymers (PFA), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polysiloxane, polysilazane, polycarbosilane and combinations thereof

16 . The passivation layer for a lithium electrode of claim 14 , wherein the inorganic particles include one type selected from the group consisting of alumina, silica, titania, zirconia, zinc oxide, antimony oxide, ceria, talc, forsterite, potassium carbonate, aluminum hydroxide, talcum, clay, talcum, barium sulfate, zeolite, kaolin, mica, montmorillonite, silicon nitride, boron nitride, barium titanate and combinations thereof.

17 . The passivation layer for a lithium electrode of claim 7 , wherein the particulate filler is used in greater than 0 parts by weight and less than or equal to 1000 parts by weight with respect to 100 parts by weight of the fibrous filler.

18 . A lithium electrode comprising a passivation layer laminated on one side or both sides of a lithium metal layer,
wherein the passivation layer is the passivation layer of claim 1 .

19 . The lithium electrode of claim 18 , wherein the lithium metal layer includes lithium metal; or an alloy of lithium metal and one type of metal selected from the group consisting of Si, Sn, C, Pt, Ir, Ni, Cu, Ti, Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Sb, Pb, In, Zn, Ba, Ra, Ge, Al and combinations thereof.

20 . A lithium secondary battery comprising the lithium electrode of claim 18 .

Assignees

• Lg Chemical Ltd

Inventors

• Hwang Euiyong
• Yang Jihye
• Koh Dongwook
• Kim Jangbae

Classifications

• H01M4/661

  Metal or alloys, e.g. alloy coatings (H01M4/669 take precedence) · CPC title

• H01M10/44

  Methods for charging or discharging (circuits for charging H02J7/00) · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M10/0525 Primary

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

• H01M2/1626

  Electricity · mapped topic