POWER STORAGE SYSTEM

• US 20100033135A1
• Filed: 03/14/2009
• Published: 02/11/2010
• Est. Priority Date: 03/15/2007
• Status: Active Grant

• Current Assignee: Kyushu Electric Power Company Incorporated, Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Kyushu Electric Power Company Incorporated, Mitsubishi Heavy Industries, Ltd.
• Inventors: Kobayashi, Katsuaki, Tajima, Hidehiko, Hashizaki, Katsuo, Nishida, Takehiko, Adachi, Kazuyuki
• Granted Patent: US 8,217,624 B2
• Time in Patent Office: Days
• US Class Current: 320/136
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: B60L 58/25 by controlling the electric load
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/443 in response to temperature
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles

Abstract

An object is to improve safety. Provided is a power storage system including a battery apparatus 1; a power converter 2 provided between the battery apparatus 1 and a load 3 and that can control power supplied from the battery apparatus 1 to the load 3; and a battery monitoring circuit 4 that detects an abnormality in the battery apparatus 1. When an abnormality in the battery apparatus 1 is detected by the battery monitoring circuit 4, the power converter 2 supplies power stored in the battery apparatus 1 to the load 3 or to an internally provided internal load at or below a current value or power value that is set in advance, or alternatively, at a current value or power value that the load 3 demands, within a range that does not exceed an upper limit that is set in advance.

Claims

1. A power storage system comprising:

a battery apparatus;

a power converter that is provided between the battery apparatus and a load and that can control power supplied from the battery apparatus to the load; and

a battery monitoring circuit that detects an abnormality in the battery apparatus,

wherein when an abnormality in the battery apparatus is detected by the battery monitoring circuit, the power converter supplies power stored in the battery apparatus to the load or to an internally provided internal load at or below a current value or power value that is set in advance, or alternatively, at a current value or power value that the load demands, within a range that does not exceed an upper limit that is set in advance.

2. A power storage system according to claim 1, further comprising:

a switching unit that electrically connects and disconnects the battery apparatus and the power converter,

wherein, when the voltage of the battery apparatus is at or below a predetermined value, the battery monitoring circuit operates the switching unit to cut the electrical connection between the battery apparatus and the power converter.

3. A power storage system according to claim 1, further comprising:

a temperature detector that detects the temperature of the battery apparatus,

wherein the power converter varies a discharge current value according to the temperature of the battery apparatus.

4. The power storage system according to claim 3 wherein, when the temperature of the battery apparatus reaches an upper temperature limit, the power converter stops discharging.

5. A power storage system according to claim 1, wherein:

the battery apparatus includes a plurality of battery cells connected in series;

each battery cell is provided with a voltage equalizing circuit that is controlled by the battery monitoring circuit; and

when the voltage of the battery apparatus is at or below a predetermined value due to discharging being performed by the power converter, the battery monitoring circuit operates each of the voltage equalizing circuits.

6. A power storage system according to claim 4, wherein:

the battery apparatus includes a plurality of battery cells connected in series;

each battery cell is provided with a voltage equalizing circuit that is controlled by the battery monitoring circuit; and

after the power converter stops discharging, the battery monitoring circuit operates each of the voltage equalizing circuits.

7. A power storage system comprising:

a battery apparatus including a plurality of battery cells connected in series;

voltage equalizing circuits, provided in correspondence to each battery cell, that equalize cell voltages among the battery cells; and

a battery monitoring circuit that detects an abnormality in each battery cell,

wherein when the battery monitoring circuit detects an abnormality in the battery cells, at least the voltage equalizing circuit corresponding to the battery cell in which the abnormality is detected is operated to perform discharging of the battery cell in which the abnormality is detected at or below a current value that is set in advance.

8. A power storage system according to claim 7, further comprising:

a temperature detector that detects the temperature of each of the battery cells,

wherein the battery monitoring circuit controls a discharge current value according to the temperatures of the battery cells.

9. A power storage system according to claim 7, wherein the voltage equalizing circuit is a transformer-type circuit that supplies energy in the battery cell in which the abnormality is detected to another normal battery cell via a transformer.