Free-standing active material/carbon nanomaterial network film as light-weight and high-power electrodes for lithium ion batteries

Patent metadata

Field	Value
Publication number	US-9831502-B2
Application number	US-201514697511-A
Country	US
Kind code	B2
Filing date	Apr 27, 2015
Priority date	Jun 30, 2014
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

An electrode includes a first free-standing carbon network, an active material deposited above the first free-standing carbon network, and a second free-standing carbon network covering the active material. The first and second carbon networks are a binder, a conductive additive and a current collector to the electrode.

First claim

What is claimed is:

1. An electrode, comprising:
a first carbon network;
a layer deposited above the first carbon network, the layer including an active material; and
a second carbon network covering the layer, wherein the first and second carbon networks are a binder, a conductive additive and a current collector to the electrode.

2. The electrode of claim 1 , wherein the active material comprises LiNi 0.5 Mn 1.5 O 4 , and the first and second carbon networks are continuous and porous.

3. The electrode of claim 2 , wherein the first and second carbon networks comprise carbon nanofibers.

4. The electrode of claim 3 , wherein the layer comprises carbon nanofibers into which LiNi 0.5 Mn 1.5 O 4 is embedded, particles of LiNi 0.5 Mn 1.5 O 4 are connected by the carbon nanofibers, and the electrode consists of carbon nanofibers and LiNi 0.5 Mn 1.5 O 4 .

5. The electrode of claim 4 , wherein the carbon nanofibers in the layer are a binder, a conductive additive and a current collector to the electrode.

6. The electrode of claim 2 , wherein the first and second carbon networks comprise carbon nanotubes, and the electrode is flexible.

7. The electrode of claim 1 , wherein the electrode provides a specific capacity of not less than 65 mAh/g at a current rate of 20 C.

8. The electrode of claim 1 , wherein a polarization resistance of the electrode is less than 0.2 ohm/g.

9. The electrode of claim 1 , wherein a weight percentage of the active material to the weight of the electrode is at least 0.45%.

10. The electrode of claim 1 , wherein the electrode is configured to deliver a capacity of more than 110 mAh/g after 100 charging and discharging at 5 C.

11. A lithium-ion battery comprising the electrode of claim 1 .

12. A method of forming an electrode, the method comprising:
depositing a carbon material using a first solution comprising the carbon material to obtain a first layer of a carbon network;
depositing a active material and the carbon material using a solution mixture to form a composite film above the first layer of the carbon network, and
depositing the carbon material using a second solution of the carbon material to obtain a second layer of the carbon network above the composite film, wherein the first layer of the carbon network, the second layer of the carbon network are a binder, a conductive additive and a current collector to the electrode.

13. The method of claim 12 , wherein the carbon network comprises a carbon nanomaterial.

14. The method of claim 13 , wherein the carbon nanomaterial comprises carbon nanofibers.

15. The method of claim 13 , wherein the carbon nanomaterial comprises carbon nanotubes.

16. The method of claim 12 , wherein the active material comprises LiNi 0.5 Mn 1.5 O 4 .

17. A lithium-ion battery having a flexible electrode formed using the method of claim 15 .

18. A lithium-ion battery formed using the method of claim 16 , wherein the electrode provides a specific capacity of not less than 65 mAh/g at a current rate of 20 C.

19. A lithium-ion battery formed using the method of claim 16 , wherein the electrode is configured to deliver a capacity of more than 110 mAh/g after 100 charging and discharging at 5 C.

20. A lithium-ion battery formed using the method of claim 16 , wherein a weight percentage of the active material to the weight of the electrode is at least 0.45%.

21. A lithium-ion battery comprising an anode and a cathode, wherein the anode comprises:
a first carbon network;
a layer deposited above the first carbon network, the layer including an active material; and
a second carbon network covering the layer, the first and second carbon networks are a binder, a conductive additive and a current collector to the anode, and wherein the cathode comprises:
a third carbon network;
a second layer deposited above the third carbon network, the second layer including the active material; and
a fourth carbon network covering the second layer, the third and fourth carbon networks are a binder, a conductive additive and a current collector to the cathode.

Assignees

• Zhou Chongwu
• Fang Xin
• Ge Mingyuan
• Rong Jiepeng
• Univ Southern California

Inventors

• Zhou Chongwu
• Fang Xin
• Ge Mingyuan
• Rong Jiepeng

Classifications

• H01M4/0404

  by coating on electrode collectors · CPC title

• H01M2220/20

  Batteries in motive systems, e.g. vehicle, ship, plane · CPC title

• 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

• H01M2004/028

  Positive electrodes · CPC title