Positive electrode active material, positive electrode, battery, battery pack, electronic device, electric vehicle, power storage device, and power system

Patent metadata

Field	Value
Publication number	US-2017187035-A1
Application number	US-201515325902-A
Country	US
Kind code	A1
Filing date	Jul 9, 2015
Priority date	Jul 31, 2014
Publication date	Jun 29, 2017
Grant date	—

Abstract

A positive electrode active material includes: secondary particles obtained by aggregation of a plurality of primary particles. The primary particles include, core particles including a lithium composite oxide, and a layer that is provided on surfaces of the core particles and includes a lithium composite oxide. The lithium composite oxide included in the core particles and the lithium composite oxide included in the layer have the same composition or almost the same composition, and crystallinity of the lithium composite oxide included in the layer is lower than crystallinity of the lithium composite oxide included in the core particles.

First claim

1 . A positive electrode active material comprising:
secondary particles obtained by aggregation of a plurality of primary particles, wherein the primary particles include,
core particles including a lithium composite oxide, and
a layer that is provided on surfaces of the core particles and includes a lithium composite oxide,
wherein the lithium composite oxide included in the core particles and the lithium composite oxide included in the layer have the same composition or almost the same composition, and
crystallinity of the lithium composite oxide included in the layer is lower than crystallinity of the lithium composite oxide included in the core particles.

2 . The positive electrode active material according to claim 1 ,
wherein, in Raman spectra, a peak intensity ratio E/A between an intensity A of a peak in a range of 550 cm −1 or more and 650 cm −1 or less and an intensity E of a peak in a range of 450 cm −1 or more and 500 cm −1 or less satisfies a relation represented by the following expression (1).
0.1≦ E/A≦ 0.35  (1)

3 . The positive electrode active material according to claim 1 ,
wherein the core particles have an average particle size that is 0.5 μm or more and 10 μm or less.

4 . The positive electrode active material according to claim 1 ,
wherein the secondary particles have an average particle size that is 1 μm or more and 50 μm or less.

5 . The positive electrode active material according to claim 1 ,
wherein the layer has an average film thickness that is 1 nm or more and 50 nm or less.

6 . The positive electrode active material according to claim 1 ,
wherein the lithium composite oxide included in the core particles has a layered rock salt structure.

7 . The positive electrode active material according to claim 1 ,
wherein the lithium composite oxide included in the core particles has an average composition that is represented by the following expression (B).
Li w M x N y O 2-z X z   (B)

(where w is 0.8<w<1.2, x+y is 0.9<x+y<1.1, y is 0≦y<0.1, and z is 0≦z<0.05; M is at least one of Ti, V, Cr, Mn, Fe, Co, Ni, Mn and Cu; N is at least one of Na, Mg, Al, Si, K, Ca, Zn, Ga, Sr, Y, Zr, Nb, Mo, Ba, La, W and Bi; X is at least one of F, Cl and S).

8 . The positive electrode active material according to claim 1 ,
wherein the lithium composite oxide included in the core particles has an average composition that is represented by the following expression (C).
Li x Co 1-y M y O 2-z X z   (C)

(where x is 0.8<x<1.2, y is 0≦y<0.15, and z is 0≦z<0.05; M is at least one of Ti, V, Cr, Mn, Fe, Ni, Mn, Cu, Na, Mg, Al, Si, K, Ca, Zn, Ga, Sr, Y, Zr, Nb, Mo, Ba, La and W; X is at least one of F, Cl and S).

9 . The positive electrode active material according to claim 1 , further comprising:
another layer that is provided on surfaces of the secondary particles and includes an oxide or a fluoride.

10 . The positive electrode active material according to claim 9 ,
wherein the oxide and the fluoride included in the other layer include at least one of Li, Ti, V, Cr, Mn, Fe, Co, Ni, Mn, Cu, Na, Mg, Al, Si, K, Ca, Zn, Ga, Sr, Y, Zr, Nb, Mo, Ba, La, W, Bi, P and B.

11 . The positive electrode active material according to claim 9 ,
wherein the oxide included in the other layer is a lithium composite oxide.

12 . The positive electrode active material according to claim 11 ,
wherein the lithium composite oxide included in the other layer has an average composition that is represented by the following expression (C).
Li w M x N y O 2-z X z   (C)

(where w is 0.8<w<1.2, x+y is 0.9<x+y<1.1, y is 0≦y<0.1, and z is 0≦z<0.05; M is at least one of Ti, V, Cr, Mn, Fe, Co, Ni, Mn and Cu; N is at least one of Na, Mg, Al, Si, K, Ca, Zn, Ga, Sr, Y, Zr, Nb, Mo, Ba, La, W and Bi; X is at least one of F, Cl and S).

13 . A positive electrode comprising:
a positive electrode active material including secondary particles obtained by aggregation of a plurality of primary particles, wherein the primary particles include,
core particles including a lithium composite oxide, and
a layer that is provided on surfaces of the core particles and includes a lithium composite oxide,
wherein the lithium composite oxide included in the core particles and the lithium composite oxide included in the layer have the same composition or almost the same composition, and
crystallinity of the lithium composite oxide included in the layer is lower than crystallinity of the lithium composite oxide included in the core particles.

14 . A battery comprising:
a positive electrode including a positive electrode active material; a negative electrode; and an electrolyte, wherein the positive electrode active material includes secondary particles obtained by aggregation of a plurality of primary particles,
wherein the primary particles include,
core particles including a lithium composite oxide, and
a layer that is provided on surfaces of the core particles and includes a lithium composite oxide,
wherein the lithium composite oxide included in the core particles and the lithium composite oxide included in the layer have the same composition or almost the same composition, and
crystallinity of the lithium composite oxide included in the layer is lower than crystallinity of the lithium composite oxide included in the core particles.

15 . A battery pack comprising:
the battery according to claim 14 .

16 . An electronic device comprising:
the battery according to claim 14 , wherein the electronic device receives power supply from the battery.

17 . An electric vehicle comprising:
the battery according to claim 14 ; a conversion device configured to perform conversion into driving power of the vehicle upon reception of power supply from the battery; and a control device configured to perform information processing regarding vehicle control based on information regarding the battery.

18 . A power storage device comprising:
the battery according to claim 14 , wherein the power storage device supplies power to an electronic device connected to the battery.

19 . The power storage device according to claim 18 , comprising:
a power information control device configured to transmit and receive a signal to and from another device via a network, wherein the power storage device performs charge/discharge control of the battery based on information received by the power information control device.

20 . A power system comprising:
the battery according to claim 14 , wherein the power system receives power supply from the battery, or allows power to be supplied to the battery from a power generation apparatus or a power network.

Assignees

• Sony Corp

Inventors

• Yanagihara Asuki
• Nakasato Shingo
• Niwata Yuki
• Hosoya Yosuke

Classifications

• H02J2105/42

  Home appliances · CPC title

• H02J2105/37

  exchanging power with electric vehicles [EV] or with hybrid electric vehicles [HEV] · CPC title

• H02J2101/28

  Wind energy · CPC title

• H02J2101/24

  Photovoltaics · CPC title

• H02J7/751

  concerning the insertion or the connection of the batteries · CPC title