Lithium ion battery cathode additive, fabrication method thereof, lithium ion battery cathode sheet and lithium ion battery

• US 10,084,189 B2
• Filed: 12/24/2014
• Issued: 09/25/2018
• Est. Priority Date: 10/26/2012
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Zhang, Qi
• Primary Examiner(s): Ruddock, Ula C
• Assistant Examiner(s): Parsons, Thomas H
• Application Number:
  US14/582,792
• Publication Number:
  US 20150111099A1
• Time in Patent Office: 1,371 Days
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/4235 Safety or regulating additives or arrangements in electrodes, separators or electrolyte H01M10/4242 takes precedence
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 2220/30 Batteries in portable systems, e.g. mobile phone, laptop
• CPC Class Codes: H01M 4/0402 Methods of deposition of the material
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/134 Electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/1395 of electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/366 as layered products
• CPC Class Codes: H01M 4/62 Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
• CPC Class Codes: H01M 4/621 Binders
• CPC Class Codes: H01M 4/624 Electric conductive fillers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A lithium ion battery cathode additive includes a core-shell coating structure formed by elemental lithium powder and a polymer coated on the surface of the elemental lithium powder, where the polymer can dissolve in a carbonic ester solvent, the polymer cannot react with N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-2-methyl pyrrolidone (NMP), tetrahydrofuran (THF), acetone or methanol, and the polymer exists stably at a temperature of 0-150° C. The lithium ion battery cathode additive may be added in a lithium ion battery cathode material as a lithium source, for compensating lithium consumption of a battery cathode in a first-time charge-discharge process. Embodiments of the present invention further provide a fabrication method of the lithium ion battery cathode additive, a lithium ion battery cathode sheet and a lithium ion battery that include the lithium ion battery cathode additive, where the lithium ion battery has high energy density and a long cycle life.

Claims

1. A lithium ion battery cathode additive, comprising:

a core-shell coating structure formed by elemental lithium powder and a polymer coated on the surface of the elemental lithium powder,

wherein the polymer comprises polyalkylene carbonate, and

wherein the polymer can dissolve in a carbonic ester solvent, the polymer cannot react with N,N-dimethylformamide, N,N-dimethylacetamide, N-2-methyl pyrrolidone, tetrahydrofuran, acetone or methanol, and the polymer exists stably at a temperature of 0-150°

C.

2. The lithium ion battery cathode additive according to claim 1, wherein the carbonic ester solvent is selected from one or more of dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate and methyl propyl carbonate.

3. A lithium ion battery cathode sheet, comprising:

a current collector;

a cathode material coated on the current collector and comprising a cathode active substance, a binding agent, a conductive agent and a lithium ion battery cathode additive, wherein the lithium ion battery cathode additive comprises a core-shell coating structure formed by elemental lithium powder and a polymer coated on the surface of the elemental lithium powder,

wherein the polymer comprises polyalkylene carbonate, and

wherein the polymer can dissolve in the carbonic ester solvent, the polymer cannot react with N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-2-methyl pyrrolidone (NMP), tetrahydrofuran (THF), acetone or methanol, and the polymer exists stably at a temperature of 0-150°

C.

4. The lithium ion battery cathode sheet according to claim 3, wherein the carbonic ester solvent is selected from one or more of dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate and methyl propyl carbonate.

5. A lithium ion battery, comprising:

a lithium ion battery cathode sheet comprising,

a current collector, and

a cathode material coated on the current collector and comprising a cathode active substance, a binding agent, a conductive agent and a lithium ion battery cathode additive;

a diaphragm, a shell and an electrolyte; and

wherein the lithium ion battery cathode additive comprises a core-shell coating structure formed by elemental lithium powder and a polymer coated on the surface of the elemental lithium powder, the polymer can dissolve in a carbonic ester solvent, the polymer cannot react with N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-2-methyl pyrrolidone (NMP), tetrahydrofuran (THF), acetone or methanol, the polymer exists stably at a temperature of 0-150°

C., and the polymer comprises polyalkylene carbonate.