Power supply unit, distributed power supply system and electric vehicle loaded therewith

• US 6,700,349 B2
• Filed: 10/09/2002
• Issued: 03/02/2004
• Est. Priority Date: 11/22/2001
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Emori, Akihiko, Miyazaki, Hideki, Kinoshita, Takuya
• Primary Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US10/266,691
• Publication Number:
  US 20030094926A1
• Time in Patent Office: 510 Days
• Field of Search: 320/104, 320/126, 320/103, 320/117, 307/10.1
• US Class Current: 320/104
• CPC Class Codes: B60L 53/11 DC charging controlled by the charging station, e.g. mode 4
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: H01M 10/05 Accumulators with non-aqueous electrolyte H01M10/39 takes precedence
• CPC Class Codes: H01M 10/06 Lead-acid accumulators semi-lead accumulators H01M10/20
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/52 Removing gases inside the secondary cell, e.g. by absorption vent plugs or other mechanical arrangements for facilitating escape of gases H01M50/30
• CPC Class Codes: H01M 12/06 with one metallic and one gaseous electrode
• CPC Class Codes: H01M 16/00 Structural combinations of different types of electrochemical generators
• CPC Class Codes: H01M 2250/20 Fuel cells in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

A power supply unit, a distributed power supply system and an electric vehicle loaded therewith, capable of charge/discharge operation are disclosed. A first cell group is connected in parallel to a second cell group in which the electrolytic solution can be electrolyzed or the generated gas can be recombined. A plurality of the parallel circuit pairs are connected in series, and the series circuit is connected with a charger/discharger to constitute the power supply unit. The charger/discharger charges the power supply unit up to a voltage at which the electrolytic solution of the second cell group is electrolyzed or the generated gas is recombined.

Claims

1. A motor vehicle comprising:

a storage battery connecting in series at least two parallel circuits, each of the at least two parallel circuits including a first cell group and a second cell group connected in parallel, said second cell group being capable of electrolysis of the electrolytic solution thereof or recombination of the generated gas thereof;

a power supply unit including a charger/discharger for controlling charge/discharge of said storage battery and adapted to charge said storage battery up to a voltage at which the electrolytic solution of said second cell group is electrolyzed or a voltage at which the generated gas is recombined; and

a motor-generator for driving a motor by electric power supplied by said power supply unit when said motor vehicle is in power running, and for generating electric power when said motor vehicle is in regeneration;

wherein when said motor vehicle is in regeneration, said storage battery is charged by the electric power of said motor-generator up to a voltage at which the electrolytic solution of said second cell group is electrolyzed or a voltage at which the generated gas is recombined.

2. A motor vehicle according to claim 1, wherein said storage battery is formed to connect in parallel a first series circuit connecting in series a plurality of first cell groups and a second series circuit connecting in series a plurality of second cell groups, said respective first cell groups being connected in parallel with said respective second cell groups, respectively, through intermediate terminals inserted for corresponding groups of said respective first cell groups and said respective second cell groups.

3. A motor vehicle according to claim 1, wherein said first cell group and second cell group are connected in parallel through a current limiter.

4. A motor vehicle according to claim 1 comprising a plurality of said storage batteries are connected in parallel.

5. A motor vehicle according to claim 1, wherein a withstanding voltage of said first cell group is higher than a withstanding voltage of said second cell group.

6. A motor vehicle according to claim 5, wherein said storage battery is formed to connect in parallel a first series circuit connecting in series a plurality of first cell groups and a second series circuit connecting in series a plurality of second cell groups, said respective first cell groups being connected in parallel with said respective second cell groups, respectively, through intermediate terminals inserted for corresponding groups of said respective first cell groups and said respective second cell groups.

7. A motor vehicle according to claim 1, wherein each of said parallel circuits is formed to connect in parallel a plurality of said second cell groups connected in series and said first cell group.

8. A motor vehicle according to claim 1, wherein said first cell group and second cell group share at least one component element.

9. A motor vehicle according to claim 8, wherein said shared component element is the electrolytic solution.

10. A motor vehicle according to claim 8, wherein at least selected one of said first cell group and second cell group has an electrode formed of selected carbon fiber and carbon nanotube.