POWER STORAGE DEVICE, POWER STORAGE CONTROL DEVICE, AND POWER STORAGE CONTROL METHOD

• US 20160233697A1
• Filed: 08/12/2014
• Published: 08/11/2016
• Est. Priority Date: 09/26/2013
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: OZAWA, Atsushi, NAKAMURA, Kazuo
• Granted Patent: US 10,587,126 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: H02J 7/0016 using shunting, discharge or bypass circuits
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Provided is a power storage device, a power storage control device, and a power storage control method for rapidly equalizing voltages of cells with a simple configuration.

A power storage device including: a plurality of cells which are connected in series; a plurality of reactance elements which are connected in series; a plurality of connection lines configured to connect the respective cells and the respective reactance elements in parallel in a one-to-one correspondence; a plurality of switching elements configured to independently open and close each of the connection lines; and a power storage control device configured to control the switching elements to cause energy to be transferred between the cells.

Claims

1. A power storage device comprising:

a plurality of cells which are connected in series;

a plurality of reactance elements which are connected in series;

a plurality of connection lines configured to connect the respective cells and the respective reactance elements in parallel in a one-to-one correspondence;

a plurality of switching elements configured to independently open and close each of the connection lines; and

a power storage control device configured to control the switching elements to cause energy to be transferred between the cells.

2. The power storage device according to claim 1, wherein the power storage control device is configured to close a first pair of connection lines which are disposed at both ends of a series of cells among the plurality of cells, and then open the first pair of connection lines and close a second pair of connection lines which are disposed at both ends of a target cell among the series of cells.

3. The power storage device according to claim 2, wherein the power storage control device is configured to select all or some of the plurality of cells as the series of cells and select a plurality of target cells.

4. The power storage device according to claim 2, wherein each of the reactance elements has a same constant.

5. The power storage device according to claim 4, wherein each of the reactance elements includes a capacitor.

6. The power storage device according to claim 5, wherein each of the reactance elements includes a reactor.

7. The power storage device according to claim 6, wherein the power storage control device is configured to switch connection of the reactance elements and the cells at a resonance frequency of the reactance elements.

8. The power storage device according to claim 1, wherein a resonance frequency of the reactance elements is a frequency when an imaginary number component in a Cole-Cole plot of internal impedances of the cells measured using an AC impedance method is 0.

9. The power storage device according to claim 2, wherein the number of switching elements and the number of connection lines are a number obtained by adding 1 to the number of cells.

10. The power storage device according to claim 2, wherein the power storage control device is configured to select the target cell and then to close the first pair of connection lines.

11. The power storage device according to claim 10, wherein the power storage control device is configured to select the target cell including a cell having a minimum voltage.

12. A power storage control device configured to control a plurality of switching elements to independently open and close a plurality of connection lines which connect a plurality of cells connected in series and a plurality of reactance elements connected in series in parallel in a one-to-one correspondence to cause energy to be transferred between the cells.

13. A power storage control method of a control device for controlling a plurality of switching elements to independently open and close a plurality of connection lines which connect a plurality of cells connected in series and a plurality of reactance elements connected in series in parallel in a one-to-one correspondence to cause energy to be transferred between the cells.