Positive electrode active material for lithium secondary cell, positive electrode for lithium secondary cell, lithium secondary cell and methods for producing these

Patent metadata

Field	Value
Publication number	US-2019027741-A1
Application number	US-201616070984-A
Country	US
Kind code	A1
Filing date	Dec 19, 2016
Priority date	Jun 18, 2015
Publication date	Jan 24, 2019
Grant date	—

Abstract

Provided are a positive electrode active material capable of inhibiting generation of gases accompanied by charging/discharging, a positive electrode and a lithium secondary cell using the positive electrode active material, and methods for manufacturing the positive electrode active material, the positive electrode, and the lithium secondary cell. The positive electrode active material comprises a coated positive electrode active material having a coating comprising at least one selected from specific phosphonic esters and specific phosphorous triesters.

First claim

1 .- 10 . (canceled)

11 . A positive electrode active material for a lithium secondary cell, comprising a coated positive electrode active material having a coating comprising at least one selected from phosphonic esters represented by the formula (1):

wherein R 1 and R 2 independently denote a substituted or nonsubstituted alkyl group having 1 to 18 carbon atoms, or a substituted or nonsubstituted aryl group; and X denotes a hydrogen atom or an alkyl group,
and phosphorous triesters represented by the formula (2):

wherein R 3 to R 5 independently denote a substituted or nonsubstituted alkyl group having 1 to 18 carbon atoms, or a substituted or nonsubstituted aryl group, and
wherein the positive electrode active material comprises excess-lithium transition metal composite oxides represented by Li 1+a Ni x Mn y M z O 2 (0<a≤0.5, 0<x<1, 0<y<1, 0<z<1, and M is Co or Fe).

12 . The positive electrode active material for a lithium secondary cell according to claim 11 , wherein the positive electrode active material comprises a lithium transition metal composite oxide.

13 . The positive electrode active material for a lithium secondary cell according to claim 11 , wherein the positive electrode active material comprises at least one selected from LiMnO 2 , Li x Mn 2 O 4 (0<x<2), LiCoO 2 , LiNiO 2 , LiCo 1-x Ni x O 2 (0.01<x<1), LiNi x Co y Mn z O 2 (x+y+z=1), LiNi 0.5 Mn 1.5 O 4 , Li α Ni β Co γ Al δ O 2 (1≤α≤1.2, β+γ+δ=1, β≥0.7, γ≤0.2), LiFePO 4 , lithium transition metal composite oxides which comprise lithium in excessive amount to stoichiometric composition, and those obtained by replacing a part of these transition metals by another metal.

14 . A positive electrode for a lithium secondary cell having, on a positive electrode current collector, a positive electrode active material layer comprising a positive electrode active material for a lithium secondary cell according to claim 11 , and
wherein the positive electrode active material comprises excess-lithium transition metal composite oxides represented by Li 1+a Ni x Mn y M z O 2 (0<a≤0.5, 0<x<1, 0<y<1, 0<z<1, and M is Co or Fe).

15 . A lithium secondary cell, comprising a positive electrode for a lithium secondary cell according to claim 14 , a negative electrode comprising a negative electrode active material, an electrolytic solution penetrating these electrodes, and an outer package accommodating these.

16 .- 20 . (canceled)

Assignees

• Nec Corp

Inventors

• Maeda Katsumi
• Hattori Sadanori

Classifications

• H01M10/0525

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

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title

• H01M4/366 Primary

  as layered products · CPC title

• H01M4/628

  Inhibitors, e.g. gassing inhibitors, corrosion inhibitors · CPC title