Nonaqueous electrolyte battery

Patent metadata

Field	Value
Publication number	US-9780378-B2
Application number	US-201414476026-A
Country	US
Kind code	B2
Filing date	Sep 3, 2014
Priority date	Sep 11, 2013
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

According to one embodiment, there is provided a nonaqueous electrolyte battery. The nonaqueous electrolyte battery includes a positive electrode, a negative electrode and a nonaqueous electrolyte. The negative electrode includes a negative electrode material layer. The negative electrode material layer includes a negative electrode active material capable of absorbing and releasing lithium at a potential of 0.78 V (vs. Li/Li + ) or more. A film containing a compound having a propylene glycol backbone is formed on at least a part of a surface of the negative electrode material layer. A content of the compound having the propylene glycol backbone in the film is 2 μmol to 40 μmol per g of a weight of the negative electrode material layer.

First claim

What is claimed is:

1. A method for producing a nonaqueous electrolyte battery comprising:
a positive electrode;
a negative electrode which comprises a negative electrode current collector and a negative electrode material layer formed on the negative electrode current collector, and the negative electrode material layer comprising a negative electrode active material capable of absorbing and releasing lithium at a potential of 0.78 V (vs. Li/Li + ) or more; and
a nonaqueous electrolyte,
wherein a film comprising a compound having a propylene glycol backbone represented by the following formula (1) is formed on at least a part of a surface of the negative electrode material layer; and
a content of the compound having the propylene glycol backbone in the film is 2 μmol to 40 μmol per g of a weight of the negative electrode material layer:

the method comprising:
preparing an electrode group which comprises the negative electrode, and
preparing a nonaqueous electrolyte which comprises a nonaqueous solvent comprising propylene carbonate in a content of 5% by volume to 50% by volume, and an electrolyte comprising LiPF 6 in a content of 70 mol % or more and dissolved in the nonaqueous solvent;
housing the electrode group and the nonaqueous electrolyte in a case to produce a battery unit;
subjecting the battery unit to initial charging and discharging;
charging the battery unit to adjust a state of charge to 20% to 80%; and
storing the battery unit in an atmosphere at a temperature of 50° C. to 80° C.

2. The method of claim 1 , wherein the storing is performed for 24 hours to 120 hours.

3. The method of claim 1 , wherein the negative electrode active material comprises a lithium titanate having a spinel structure.

4. The method of claim 1 , wherein the film further comprises a compound having an alkoxyl group.

5. The method of claim 1 , wherein the electrolyte further comprises at least one selected from the group consisting of lithium perchlorate (LiClO 4 ), lithium tetrafluoroborate (LiBF 4 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium trifluoromethanesulfonate (LiCF 3 SO 3 ), lithium bistrifluoroinethylsulfonyl imide [LiN(CF 3 SO 2 ) 2 ], lithium N,N-bis(trilluoromethanesulfonyl)imide (LiTFSI), lithium N,N-bispentafluoroethanesulfonyl amide (LiBETI), lithium bis(fluorosulfonyl)imide (LiFSI), lithium difluorophosphate (LiPF 2 O 2 ), lithium monofluorophosphate (LiPFO 3 H), lithium bisoxalatoborate (LiB(C 2 O 4 ) 2 ), lithium difluoro(oxalato)borate (LiF 2 BC 2 O 4 ), and lithium difluoro(trifluoro-2-oxide-2-tritluoro-methylpropionato(2-)-0,0)borate (LiBF 2 (OCOOC(CF 3 ) 2 ).

6. The method of claim 1 , wherein the electrolyte further comprises at least one lithium salt comprising boron.

Assignees

• Toshiba Kk

Inventors

• Yamamoto Dai
• Watanabe Yuki
• Saruwatari Hidesato
• Kuriyama Kazuya
• Satake Hideki

Classifications

• H01M10/446

  Initial charging measures · CPC title

• H01M10/0569

  characterised by the solvents · CPC title

• H01M10/0568

  characterised by the solutes · CPC title

• H01M10/0525

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

• H01M4/485

  of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy (H01M4/505, H01M4/525 take precedence) · CPC title