Cathode active material, secondary battery comprising the same, and method of manufacturing the positive active material

Patent metadata

Field	Value
Publication number	US-2016141607-A1
Application number	US-201414576962-A
Country	US
Kind code	A1
Filing date	Dec 19, 2014
Priority date	Nov 28, 2013
Publication date	May 19, 2016
Grant date	—

Abstract

A positive active material including: a core comprising a metal oxide, a non-metal oxide, or a combination thereof capable of intercalation and deintercalation of lithium ions or sodium ions; and a non-conductive carbonaceous film including oxygen on at least one portion of a surface of the core; a lithium battery including the positive active material; and a method of manufacturing the positive active material.

First claim

What is claimed is:

1 . A positive active material comprising:
a core comprising a metal oxide, a non-metal oxide, or a combination thereof capable of intercalation and deintercalation of lithium ions or sodium ions; and a non-conductive carbonaceous film containing oxygen on at least one portion of a surface of the core.

2 . The positive active material of claim 1 , wherein the non-conductive carbonaceous film comprises at least one carbon compound having a functional group of the formula —C(═O)R a , —C(═O)OR a , and —OC(═O)OR a , wherein R a is hydrogen, a C1-C10 alkyl group, or a C6-C20 aryl group.

3 . The positive active material of claim 2 , wherein the carbon compound comprises a substituted or unsubstituted C 6 -C 30 aromatic compound, a substituted or unsubstituted C 5 -C 30 heterocyclic compound, or a combination thereof.

4 . The positive active material of claim 1 , wherein the core is represented by Formula 1, and comprises a non-conductive carbonaceous film containing oxygen on at least one portion of the surface of the core:
Li a M b O 2-c (X1) c   Formula 1

wherein in Formula 1,
a is 0.8≦a≦1.2, b is 0<b≦1, c is 0≦c≦1, and
M is at least one element selected from manganese (Mn), nickel (Ni), cobalt (Co), copper (Cu), magnesium (Mg), sodium (Na), calcium (Ca), titanium (Ti), zinc (Zn), gallium (Ga), germanium (Ge), aluminum (Al), chromium (Cr), strontium (Sr), molybdenum (Mo), tungsten (W), vanadium (V), titanium (Ti), zirconium (Zr), ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), silver (Ag), gold (Au), hafnium (Hf), tin (Sn), and platinum (Pt), and
X1 is at least one element selected from oxygen (O), fluorine (F), sulfur (S), and phosphorus (P).

5 . The positive active material of claim 4 , wherein a relationship between a ratio (I A /I B ) of a peak intensity at a binding energy of about 531 eV to about 533 eV with respect to a peak intensity at a binding energy of about 528 eV to about 530 eV in an O1s spectrum of an X-ray photoelectron spectroscopy analysis of the surface of the core and an amount (D) of carbon in the non-conductive carbonaceous film with respect to 100 parts by weight of the core on the surface of the core is represented by Inequation 1:
[( I A /I B )/ D]≧ 10 parts by weight −1 .  Inequation 1

6 . The positive active material of claim 4 , wherein an amount of carbon in the non-conductive carbonaceous film is about 0.001 part by weight to about 0.3 part by weight, based on 100 parts by weight.

7 . The positive active material of claim 4 , wherein a thickness of the non-conductive carbonaceous film is about 0.1 nm to about 5.0 nm.

8 . The positive active material of claim 1 , wherein the core is represented by Formula 2, and the non-conductive carbonaceous film containing oxygen is formed on at least one portion of a surface of the core:
q Li 2 MnO 3 .(1 −q )Li(M1)O 2   Formula 2
wherein in Formula 2,
0<q<1, and
M1 is at least one element selected from Mn, Ni, Co, Cu, Mg, Na, Ca, Ti, Zn, Ga, Ge, Al, Cr, Sr, Mo, W, V, Ti, Zr, Ru, Rh, Pd, Os, Ir, Ag, Au, Hf, Sn, and Pt.

9 . The positive active material of claim 8 , wherein the non-conductive carbonaceous film further comprises Li 2 CO 3 .

10 . The positive active material of claim 8 , wherein in a C1s spectrum of an X-ray photoelectron spectroscopy analysis of the non-conductive carbonaceous film, a ratio of I D /I C may be 0.3 or more, wherein I D denotes a peak intensity of Li 2 CO 3 phase at a binding energy of 288 eV to 293 eV, and I C denotes a peak intensity of C—C bond phase at a binding energy of 282 eV to 285 eV.

11 . The positive active material of claim 1 , wherein the core is represented by Formula 3 below, and the non-conductive carbonaceous film containing oxygen is disposed on at least one portion of the surface of the core:
Na x (Q)O 2+e   Formula 3
wherein in Formula 3,
Q is at least two transition metal elements selected from Groups 4 to 12 of the periodic table, and
0.5≦x≦1, and −0.3≦e≦1.

12 . The positive active material of claim 1 , further comprising an oxygen depletion layer between the core and the non-conductive carbonaceous film.

13 . The positive active material of claim 12 , wherein the oxygen depletion layer is a layer formed by reduction of at least one portion of the surface of the core.

14 . A secondary battery comprising:
a positive electrode; an electrolyte; and a negative electrode, wherein the positive electrode comprises the positive active material according to claim 1 .

15 . A method of preparing of the positive active material according to claim 1 , the method comprising:
mixing a core comprising a metal oxide, a non-metal oxide, or a combination thereof capable of intercalation and deintercalation of lithium ions or sodium ions, a carbonaceous precursor having at least one hydroxy group or carboxyl group, and a solvent to chemically adsorb the carbonaceous precursor on at least one portion of the surface of the core; and heat treating the core on which the carbonaceous precursor is formed to form a non-conductive carbonaceous film containing oxygen on the core to prepare the positive active material.

16 . The method of claim 15 , wherein the carbonaceous precursor is a substituted or unsubstituted benzene, a substituted or unsubstituted naphthalene, a substituted or unsubstituted phenalene, a substituted or unsubstituted phenanthrene, a substituted or unsubstituted anthracene, a substituted or unsubstituted triphenylene, a substituted or unsubstituted pyrene, a substituted or unsubstituted chrysene, a substituted or unsubstituted naphthacene, a substituted or unsubstituted picene, a substituted or unsubstituted perylene, a substituted or unsubstituted pentaphene, a substituted or unsubstituted hexacene, a substituted or unsubstituted pyridine, a substituted or unsubstituted pyrazine, a substituted or unsubstituted pyrimidine, a substituted or unsubstituted pyridazine, a substituted or unsubstituted quinoline, a substituted or unsubstituted phthalazine, a substituted or unsubstituted quinoxaline, a substituted or unsubstituted quinazoline, a substituted or unsubstituted cinnoline, a substituted or unsubstituted phenanthridine, a substituted or unsubstituted phenanthroline, or a substituted or unsubstituted phenazine.

17 . The method of claim 15 , wherein the process of chemically adsorbing the carbonaceous precursor on at least one portion of the surface of the core occurs via a chemical bond formed by a dehydration reaction between a hydroxy group of the surface of the core and a hydroxy group or a carboxyl group of the carbonaceous precursor.

18 . The method of claim 17 , wherein the dehydration reaction further includes a heat treatment process.

19 . The method of claim 18 , wherein the heat treatment process is performed at a temperature of about 200° C. to about 400° C. for about 1 hour to about 5 hours.

20 . The method of claim 15 , wherein the heat treating is performed at a temperature of about 400° C. to about 800° C.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Park Kwangjin
• Yoon Jaegu
• Shon Jeongkuk
• Song Minsang
• Chang Jaejun
• Ji Sangmin
• Choi Jaeman
• Ham Dongjin

Classifications

• H01M4/366 Primary

  as layered products · CPC title

• H01M4/583

  Carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title

• H01M4/049

  Manufacturing of an active layer by chemical means · CPC title

• H01M4/60

  of organic compounds · CPC title