ELECTROCHEMICAL STORAGE CELL

• US 20090162739A1
• Filed: 12/22/2008
• Published: 06/25/2009
• Est. Priority Date: 12/25/2007
• Status: Active Grant

• Current Assignee: BYD Company Limited
• Original Assignee: BYD Company Limited
• Inventors: Shen, Xi, Han, Lei, Zheng, Weixin, Gu, Hongjuan
• Granted Patent: US 8,865,335 B2
• Time in Patent Office: Days
• US Class Current: 429/94
• CPC Class Codes: H01M 10/0422 Cells or battery with cylindrical casing
• CPC Class Codes: H01M 10/0431 Cells with wound or folded electrodes H01M10/045 takes precedence
• 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 10/615 Heating or keeping warm
• CPC Class Codes: H01M 10/625 Vehicles
• CPC Class Codes: H01M 10/633 characterised by algorithms, flow charts, software details or the like
• CPC Class Codes: H01M 10/637 characterised by the use of reversible temperature-sensitive devices, e.g. NTC, PTC or bimetal devices; characterised by control of the internal current flowing through the cells, e.g. by switching means for preventing undesired use or discharge H01M50/572
• CPC Class Codes: H01M 10/6553 Terminals or leads
• 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 10/658 by thermal insulation or shielding
• CPC Class Codes: H01M 50/15 for prismatic or rectangular cells H01M50/153 takes precedence
• CPC Class Codes: H01M 50/152 for cells having curved cross-section, e.g. round or elliptic H01M50/15, H01M50/153 take precedence
• 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 50/522 Inorganic material
• CPC Class Codes: H01M 50/552 characterised by their shape
• CPC Class Codes: H01M 50/581 in response to temperature
• CPC Class Codes: H01M 50/591 Covers
• CPC Class Codes: H01M 6/5038 Heating or cooling of cells or batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries

Abstract

An electrochemical storage cell is disclosed that comprises a cathode sheet, an anode sheet, and a separator sheet between the cathode and anode sheets. A metal foil current collector extends from a longitudinal edge of the cathode sheet. A further metal foil current collector extends from a longitudinal edge of the anode sheet. The anode sheet, cathode sheet, and separator sheet are wound in a flattened coil shape to produce a core in which the metal foil current collector of the cathode sheet extends beyond the separator sheet at one end of the core and the metal current collector of the anode sheet extends beyond the separator sheet at an opposite end of the core. Overlying layers of the metal foil current collector of the cathode sheet are compressed together and placed in electrical communication with a positive terminal of the cell while overlying layers of the metal foil current collector of the anode sheet are compressed together and placed in electrical communication a negative terminal of the cell.

Claims

1. An electrochemical storage cell comprising:

a cathode sheet comprising active materials formed on a substrate and a metal foil current collector extending from a longitudinal edge of the cathode sheet;

an anode sheet comprising active materials formed on a substrate and a metal foil current collector extending from a longitudinal edge of the anode sheet;

a separator sheet between the cathode sheet and the anode sheet;

a positive terminal; and

a negative terminal;

wherein the cathode sheet, separator sheet, and anode sheet are wound in a flattened coil shape to produce a core, with the metal foil current collector of the cathode sheet extending beyond the separator sheet at one end of the core and with the metal foil current collector of the anode sheet extending beyond the separator sheet at an opposite end of the core; and

wherein overlying layers of the metal foil current collector of the cathode sheet are compressed together and electrically connected to the positive terminal, and wherein overlying layers of the metal foil current collector of the anode sheet are compressed together and electrically connected to the negative terminal.

2. The cell of claim 1, wherein the metal foil current collectors of the cathode sheet are welded together at the connection point with the positive terminal, and the metal foil current collectors of the anode sheet are welded together at the connection point with the negative terminal.

3. The cell of claim 1, wherein the compressed overlying layers of metal foil current collectors are electrically connected to the respective terminal through a resilient strip of conductive material having a first end connected to the compressed overlying layers of metal foil and a second end in electrical communication with the respective terminal.

4. The cell of claim 1, wherein the current collector for the cathode sheet is a sheet of metal foil and is the substrate for the cathode active materials, and wherein the active cathode materials are not present on the portion of the current collector for the cathode that extends beyond the separator sheet.

5. The cell of claim 1, wherein the current collector for the cathode sheet comprises at least one sheet of metal foil that forms the substrate for the cathode active materials and a ribbon of metal foil attached to the at least one sheet of metal foil, wherein the ribbon extends beyond the separator sheet.

6. The cell of claim 1, wherein the current collector for the anode sheet comprises at least a single sheet of metal foil that forms the substrate for the cathode active materials, and wherein the active anode materials are not present on the portion of the current collector for the anode that extends beyond the separator sheet.

7. The cell of claim 1, wherein the current collector for the anode sheet comprises at least one sheet of metal foil that forms the substrate for the anode active materials and a ribbon of metal foil attached to the at least one sheet, wherein the ribbon extends beyond the separator sheet.

8. The cell of claim 6, wherein the metal foil substrate of the anode is copper.

9. The cell of claim 4, wherein the metal foil substrate of the cathode is aluminum.

10. The cell of claim 1, wherein the anode sheet and cathode sheet are wound so as to start at different positions within the core.

11. The cell of claim 1, wherein the anode and cathode sheets have different lengths.

12. An electrochemical storage cell comprising:

a protective, prismatic-shaped shell having a positive terminal at one end thereof and a negative terminal at the other end thereof, wherein the shell and terminals are adapted for side-by-side connection with other electrochemical storage cells to form a battery pack;

a core that fits snugly within the shell, the core comprising

an anode sheet comprising active materials formed on a substrate and a metal foil current collector extending from a longitudinal edge of the anode sheet;

a cathode sheet comprising active materials formed on a substrate and a metal foil current collector extending from a longitudinal edge of the cathode sheet;

a separator sheet between the cathode sheet and the anode sheet;

wherein the cathode sheet, separator sheet, and anode sheet are wound in a flattened coil shape, with the metal foil current collector of the cathode sheet extending beyond the separator sheet at one end of the core and with the metal foil current collector of the anode sheet extending beyond the separator sheet at an opposite end of the core; and

wherein overlying layers of the metal foil current collector of the cathode sheet are compressed together and electrically connected to the positive terminal, and wherein overlying layers of the metal foil current collector of the anode sheet are compressed together and electrically connected to the negative terminal.

13. The cell of claim 12, wherein the metal foil current collector of the cathode sheet comprises a ribbon of metal foil connected to the substrate of the cathode sheet, and wherein the metal foil current collector of the anode sheet comprises a ribbon of metal foil connected to the substrate of the anode sheet.

14. The cell of claim 12, wherein the metal foil current collector of the cathode sheet comprises a region of the substrate of the cathode sheet that does not include the active materials thereon, and wherein the metal foil current collector of the anode sheet comprises a region of the substrate of the anode sheet that does not include the active materials thereon.

15. The cell of claim 12, wherein the electrochemical cell is disposed in a battery system that is mounted in an electric powered vehicle and connected to store and provide electric power to the vehicle.

16. The cell of claim 12, wherein the electrochemical cell is disposed in a battery system that is mounted in an electric powered vehicle and connected to provide electric power to drive an electric motor that moves the electric powered vehicle.

17. A battery system for an electric powered vehicle comprising:

a plurality of battery packs connected electrically in series with one another, wherein each battery pack includes a plurality of battery cells that are connected electrically in series with one another, and wherein each of the plurality of battery cells includes a core comprising

a cathode sheet having a cathode substrate for active cathode materials, a separator sheet, and an anode sheet having an anode substrate for active anode materials, wherein the cathode sheet, anode sheet, and separator sheet are wound in a flattened coil shape,

wherein the cathode substrate extends beyond the separator sheet at one end of the core and the anode substrate extends beyond the separator sheet at an opposite end of the core,

wherein overlying layers of the cathode sheet extending beyond the separator sheet are compressed together and connected to a positive terminal of the battery cell, and wherein overlying layers of the anode sheet extending beyond the separator sheet are compressed together and connected to the negative terminal of the battery.

18. The battery system of claim 17, wherein the compressed overlying layers of the anode and cathode substrates are electrically connected with the respective terminal through a resilient strip of conductive material having a first end connected to the compressed overlying layers and a second end electrically connected with the respective terminal.

19. The battery system of claim 17, wherein the battery system is mounted in an electric powered vehicle and connected to store and provide electric power to the vehicle.

20. The battery system of claim 17, wherein the battery system is mounted in an electric powered vehicle and connected to provide electric power to drive an electric motor that moves the electric powered vehicle.