Lithium battery containing cathode material and electrolyte additives for high voltage application

Patent metadata

Field	Value
Publication number	US-11688883-B2
Application number	US-202016916223-A
Country	US
Kind code	B2
Filing date	Jun 30, 2020
Priority date	Sep 16, 2015
Publication date	Jun 27, 2023
Grant date	Jun 27, 2023

Abstract

A lithium secondary cell having an operating voltage ≥4.35V, comprising a cathode comprising a doped LiCoO2 active material, an anode comprising graphite, and an electrolyte comprising a carbonate-based solvent, a lithium salt and both a succinonitrile (SN) and a lithium bis(oxalato)borate (LiBOB) additive wherein during the discharge at 45° C. from a state of charge (SOC) of 100% at 4.5V to a SOC of 0 at 3V at a C/10 rate the difference of the SOC at 4.42V and 4.35V is at least 7% but less than 14%, and wherein the active material is doped by at least 0.5 mole % of either one or more of Mn, Mg and Ti.

First claim

The invention claimed is:

1. A lithium secondary cell having an operating voltage ≥4.35V, comprising
a cathode comprising a powderous, doped LiCoO 2 active material comprising a core and a surface layer, wherein the active material is doped by at least 0.5 mole % of one or more of Mn, Mg and Ti, and wherein
when the active material is doped by Mg, the Mg:Co ratio in the surface layer versus the Mg:Co ratio in the core is >2, or
when the active material is doped by Mn, the Mn:Co ratio in the surface layer versus the Mn:Co ratio in the core is >2, or
when the active material is doped by Ti, the Ti:Co ratio in the surface layer versus the Ti:Co ratio in the core is >2;

an anode comprising graphite, and
an electrolyte comprising a carbonate-based solvent, a lithium salt and both a succinonitrile (SN) and a lithium bis(oxalato) borate (LiBOB) additive,
wherein the core of the active material has a layered crystal structure and consists of the elements Li, a metal M and oxygen, wherein the metal M has the formula M=Co 1-a″ M′ a″ , with 0≤a″≤0.05, wherein M′ is Al or M′ is Al and one or more elements selected from the group consisting of Mg, Ti, Ga and B; and the surface layer comprises Li, Co, and inorganic N-based oxides or lithiated oxides, wherein N is one or more metals of the group consisting of Al, Mg, Ti, Ni, Mn, Fe, Cu, Ca, Ba, Y, Sn, Sb, Na, Zn, Zr and Si; and wherein in the active material the molar ratio Al:Co>0.004.

2. The lithium secondary cell of claim 1 , wherein during the discharge at 45° C. from a state of charge (SOC) of 100% at 4.5V to a SOC of 0% at 3V at a C/10 rate the difference of the SOC at 4.42V and 4.35V is at least 7% but less than 14%.

3. The lithium secondary cell of claim 1 , wherein the electrolyte comprises 0.5-3 wt % succinonitrile.

4. The lithium secondary cell of claim 1 , wherein the electrolyte comprises 0.5-3 wt % succinonitrile and 0.5-5 wt % lithium bis(oxalato)borate.

5. The lithium secondary cell of claim 1 , wherein the carbonate-based solvent comprises one or more of ethylene carbonate (EC), vinylene carbonate (VC), fluoroethylene carbonate (FEC) or diethyl carbonate (DEC), and the lithium salt consists of LiPF 6 .

6. The lithium secondary cell of claim 1 , wherein the surface layer of the active material comprises a plurality of islands densely sintered to the core, the islands comprising Ni and at least 5 mole % of Mn.

7. The lithium secondary cell of claim 6 , wherein the Mn concentration in the islands is at least 4 mole % higher than the Mn concentration in the core, and wherein the Ni concentration in the islands is at least 2 mole % higher than the Ni concentration in the core.

8. The lithium secondary cell of claim 1 , wherein the active material has the general composition Li x Co 1-a-b M 1 a M 2 b O 2-d with 0.97<x<1.01, 0.005≤a<0.10, 0.001≤b≤0.02, and −0.1≤d≤0.1, wherein M 1 is one or both of Ni and Mn, M 2 is one or more metals selected from the group consisting of Al, Mg, Ca, Ti, and Zr, wherein particles of the active material comprise a core P2 and a shell P1, wherein P1 consists of a plurality of islands densely sintered to the core P2, wherein the weight ratio P1/P2 is <0.5 and P1+P2=1, wherein the molar content of M 1 in P2 is less than the molar content of M 1 in P1, and the molar content of (M 2 +Co) in P2 is more than the molar content of (M 2 +Co) in P1.

9. The lithium secondary cell of claim 1 , wherein the active material has the general composition Lix′Co 1-a′-b′ M 3 a′ M 4 b′ O 2-d′ with 0.97<x<1.01, 0.005≤a′<0.10, 0.001≤b′≤0.02, and −0.1≤d′≤0.1, wherein M 3 is one or both of Ni and Mn, M 4 is Al, or Al and one or more metals selected from the group consisting of Mg, Ca, Ti, and Zr, wherein particles of the active material comprise a core P2 and a shell P1, wherein P1 comprises Co and M 3 , wherein P2 comprises Co and Al, wherein P1 consists of a plurality of islands densely sintered to the core and the weight ratio P1/P2 is <0.5 and P1+P2=1, wherein the molar content of M 3 in P2 is less than the molar content of M 3 in P1, and the molar content of Al in P2 is more than the molar content of Al in P1.

10. The lithium secondary cell of claim 1 , wherein M′ is Al or M′ is Al and one or both of Ga and B; and the surface layer consists of Li, Co, and inorganic N-based oxides or lithiated oxides, wherein N is Al, Ti and Mg, or N is Al, Ti, Mg and one or more metals selected from the group consisting of Fe, Cu, Ca, Ba, Y, Sn, Sb, Na, Zn, Zr and Si.

11. The lithium secondary cell of claim 10 , wherein the molar ratio Li:(Co+Al) is more than 0.98 and less than 1.01.

12. The lithium secondary cell of claim 10 , wherein the active material has an electrical conductivity less than 10 −5 S/cm measured under a pressure of 63.7 MPa at 25° C.

13. The lithium secondary cell of claim 1 , wherein the active material has the general composition Li x Co 1-a-b M 1 a M 2 b O 2-d with 0.97<x, 0.005≤a<0.10, 0.001≤b≤0.02, and −0.1≤d≤0.1, wherein M 1 is one or both of Ni and Mn, M 2 is one or more metals selected from the group consisting of Al, Mg, Ca, Ti, and Zr, wherein particles of the active material comprise a core P2 and a shell P1, wherein P1 consists of a plurality of islands densely sintered to the core P2, wherein the weight ratio P1/P2 is <0.5 and P1+P2=1, wherein the molar content of M 1 in P2 is less than the molar content of M 1 in P1, and the molar content of (M 2 +Co) in P2 is more than the molar content of (M 2 +Co) in P1.

Assignees

• Umicore Nv
• Umicore Korea Ltd

Inventors

• Xia Xin
• Blangero Maxime
• Zhang Jing
• Yang Wenlong
• Paulsen Jens

Classifications

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title

• H01M10/0569 Primary

  characterised by the solvents · CPC title

• H01M10/0568

  characterised by the solutes · CPC title

• C01G51/42 Primary

  containing alkali metals, e.g. LiCoO2 · CPC title

• H01M2300/0037

  Mixture of solvents · CPC title