BATTERY ELECTRODE SHEET

• US 20090311607A1
• Filed: 08/27/2009
• Published: 12/17/2009
• Est. Priority Date: 12/25/2007
• Status: Active Grant

• Current Assignee: BYD Company Limited
• Original Assignee: BYD Company Limited
• Inventors: Wang, Changping, Han, Lei
• Granted Patent: US 8,276,695 B2
• Time in Patent Office: Days
• US Class Current: 429/246
• 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 10/0587 of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/615 Heating or keeping warm
• CPC Class Codes: H01M 10/625 Vehicles
• CPC Class Codes: H01M 10/647 Prismatic or flat cells, e.g. pouch cells
• CPC Class Codes: H01M 10/653 characterised by electrically insulating or thermally conductive materials
• CPC Class Codes: H01M 10/6553 Terminals or leads
• CPC Class Codes: H01M 10/6556 Solid parts with flow channel passages or pipes for heat exchange closed pipes H01M10/6552
• CPC Class Codes: H01M 10/6567 Liquids
• CPC Class Codes: H01M 10/6571 Resistive heaters arrangements for heating the battery by its resistance to the internal current H01M10/637
• CPC Class Codes: H01M 10/66 Heat-exchange relationships between the cells and other systems, e.g. central heating systems or fuel cells
• CPC Class Codes: H01M 2004/025 with shapes other than plane or cylindrical
• CPC Class Codes: H01M 2200/00 Safety devices for primary or secondary batteries
• CPC Class Codes: H01M 4/0404 by coating on electrode collectors
• CPC Class Codes: H01M 4/043 involving compressing or compaction
• 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 4/139 Processes of manufacture
• CPC Class Codes: H01M 4/62 Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
• CPC Class Codes: H01M 50/147 : Lids or covers
• CPC Class Codes: H01M 50/176 : for prismatic or rectangular cells H01M50/181 takes precedence
• CPC Class Codes: H01M 50/184 : characterised by their shape or structure
• CPC Class Codes: H01M 50/186 : characterised by the disposition of the sealing members
• CPC Class Codes: H01M 50/24 : adapted for protecting batteries from their environment, e.g. from corrosion thermal insulation H01M10/658
• CPC Class Codes: H01M 50/3425 : in the form of rupturable membranes or weakened parts, e.g. pierced with the aid of a sharp member
• CPC Class Codes: H01M 50/417 : Polyolefins
• CPC Class Codes: H01M 50/46 : Separators, membranes or diaphragms characterised by their combination with electrodes
• CPC Class Codes: H01M 50/469 : tubular or cylindrical
• CPC Class Codes: H01M 50/503 : characterised by the shape of the interconnectors
• CPC Class Codes: H01M 50/516 : by welding, soldering or brazing
• CPC Class Codes: H01M 50/528 : Fixed electrical connections, i.e. not intended for disconnection
• CPC Class Codes: H01M 50/579 : in response to shock
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries

Abstract

A battery electrode sheet comprises a conductive substrate and an electrode material coated on at least a portion of the conductive substrate. The coated portion of the conductive substrate comprises a first region, a second region, and a transition region between the first and second regions. The electrode material on the first region has a first thickness; and the electrode material on the second region has a second thickness, which is smaller than the first thickness. The electrode material on the transition region has a thickness that decreases between the first and second regions.

Claims

1. A battery electrode sheet comprising:

a conductive substrate; and

an electrode material coated on at least a portion of the conductive substrate;

wherein the coated portion of the conductive substrate comprises a first region, a second region, and a transition region between the first and second regions;

wherein the electrode material on the first region has a first thickness;

the electrode material on the second region has a second thickness, smaller than the first thickness; and

the electrode material on the transition region has a thickness that decreases between the first and second regions.

2. The sheet of claim 1, wherein the first thickness is in a range of between about 20 and about 350 μ

m.

3. The sheet of claim 1, wherein the second thickness is in a range of between about 10 and about 250 μ

m.

4. The sheet of claim 1, wherein the ratio of the first thickness to the second thickness is in a range of between about 2:

1 and about 10;

1.

5. The sheet of claim 1, wherein the thickness of the electrode material on the transition region decreases in a straight line between the first and second regions.

6. The sheet of claim 5, wherein the thinning of the electrode material is at a gradient of between about 5 and about 300 μ

m/mm.

7. The sheet of claim 1, wherein the transition region has a width in a range of between about 1 and about 10 mm.

8. The sheet of claim 1, wherein the second region has a width in a range of between about 1 and about 10 mm.

9. The sheet of claim 1, wherein the first thickness is substantially uniform along the first region;

and the second thickness is substantially uniform along the second region.

10. The sheet of claim 1, wherein the substrate further comprises an exposed region at the edge of the sheet, wherein the exposed region has no electrode material coating.

11. The sheet of claim 10, wherein the exposed region has a width in a range of between about 10 and about 100 mm.

12. The sheet of claim 1, further comprising an insulating coating, wherein the insulation layer covers at least the transition region and the second region.

13. The sheet of claim 12, wherein the insulating coating has a thickness in a range of between about 5 and about 150 μ

m.

14. The sheet of claim 12, wherein the insulating coating comprises a material selected from the group consisting of polyphenylene sulfide, polyurethane, polyethylene, polypropylene, and combinations thereof.

15. The sheet of claim 14, wherein the insulating coating is formed from polyphenylene sulfide.

16. A method for preparing a battery electrode sheet comprising:

coating an electrode material onto at least a portion of a conductive substrate;

wherein the coated portion of the conductive substrate comprises a first region, a second region, and a transition region between the first and second regions;

wherein the electrode material on the first region has a first thickness;

the electrode material on the second region has a second thickness, smaller than the first thickness; and

the electrode material on the transition region has a thickness that decreases between the first and second regions.

17. The method of claim 16, further comprising:

removing the electrode material partially from the substrate.

18. The method of claim 16, further comprising:

drying the coated electrode plate.

19. The method of claim 16, further comprising:

pressing the coated electrode sheet.

20. A battery core comprising:

a cathode sheet comprising;

a conductive substrate; and

an electrode material coated on at least a portion of the conductive substrate;

wherein the coated portion of the conductive substrate comprises a first region, a second region, and a transition region between the first and second regions;

wherein the electrode material on the first region has a first thickness;

the electrode material on the second region has a second thickness, smaller than the first thickness; and

the electrode material has a thickness that decreases between the first and second regions;

an anode sheet; and

a separator sheet disposed between the cathode sheet and the anode sheet.