Secondary battery, battery pack, and vehicle

Patent metadata

Field	Value
Publication number	US-10347906-B2
Application number	US-201715698345-A
Country	US
Kind code	B2
Filing date	Sep 7, 2017
Priority date	Mar 17, 2017
Publication date	Jul 9, 2019
Grant date	Jul 9, 2019

Abstract

According to one embodiment, a secondary battery is provided. The secondary battery includes a negative electrode including a negative electrode current collector, a negative electrode terminal electrically connected to the negative electrode current collector, a joint electrically connecting the negative electrode terminal and the negative electrode current collector, and a water repellent layer covering the joint. The joint is covered with the inner surface of the water repellent layer. A contact angle θ with respect to water on an outer surface of the water repellent layer satisfies 80°≤θ.

First claim

What is claimed is:

1. A secondary battery comprising:
a negative electrode comprising a negative electrode current collector;
a negative electrode terminal electrically connected to the negative electrode current collector;
a joint electrically connecting the negative electrode terminal and the negative electrode current collector;
a water repellent layer covering the joint;
a positive electrode; and
an aqueous electrolyte containing at least one of lithium salt and sodium salt,
wherein each of the negative electrode terminal and the negative electrode current collector comprises zinc or an alloy containing zinc, or the negative electrode comprises a coating layer containing boehmite in at least a part of a surface of each of the negative electrode terminal and the negative electrode current collector, and
the joint is covered with an inner surface of the water repellent layer, and a contact angle θ with respect to water on an outer surface of the water repellent layer satisfies 80°≤θ.

2. The secondary battery according to claim 1 ,
wherein the negative electrode current collector comprises a negative electrode tab portion, and
at least a part of an edge portion of the negative electrode current collector except the negative electrode tab portion is covered with the water repellent layer.

3. The secondary battery according to claim 2 , wherein a part of the negative electrode tab portion is covered with the coating layer.

4. The secondary battery according to claim 1 , wherein a part of the negative electrode terminal is covered with the coating layer.

5. The secondary battery according to claim 1 , wherein the contact angle θ of the water repellent layer with respect to water satisfies 100°≤θ.

6. The secondary battery according to claim 1 , wherein the water repellent layer contains at least one water repellent material selected from the group consisting of polytetrafluoroethylene, tetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, polypropylene, polyethylene, polyimide, polystyrene, and silicone.

7. The secondary battery according to claim 1 , wherein a thickness of the water repellent layer falls within a range of 0.1 μm to 500 μm.

8. The secondary battery according to claim 1 , wherein each of the negative electrode terminal and the negative electrode current collector comprises the coating layer.

9. The secondary battery according to claim 1 , wherein the negative electrode comprises a negative electrode active material-containing layer, and
the negative electrode active material-containing layer comprises an active material containing at least one selected from the group consisting of a spinel-type lithium titanium oxide and an anatase-type titanium oxide.

10. A battery pack comprising the secondary battery according to claim 1 .

11. The battery pack according to claim 10 , further comprising an external power distribution terminal and a protective circuit.

12. The battery pack according to claim 10 , further comprising plural of the secondary batteries,
wherein the secondary batteries are electrically connected in series, in parallel, or in a combination of series connection and parallel connection.

13. A vehicle comprising the battery pack according to claim 10 .

14. The vehicle according to claim 13 , which comprises a mechanism configured to convert kinetic energy of the vehicle into regenerative energy.

Assignees

• Toshiba Kk

Inventors

• Ise Kazuki
• Matsuno Shinsuke
• Takami Norio
• Inagaki Hiroki

Classifications

• H01M50/176

  for prismatic or rectangular cells (H01M50/181 takes precedence) · CPC title

• H01M10/3945

  containing additives or special arrangements in the sodium compartment · CPC title

• H01M10/36 Primary

  Accumulators not provided for in groups H01M10/05-H01M10/34 · CPC title

• H01M10/4207

  for several batteries or cells simultaneously or sequentially · CPC title

• H01M4/244 Primary

  Zinc electrodes · CPC title