Controlling charging current supplied to plurality of cell modules connected in parallel

• US 9,438,061 B2
• Filed: 11/21/2013
• Issued: 09/06/2016
• Est. Priority Date: 12/11/2012
• Status: Active Grant

• Current Assignee: Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Takeyama, Akira
• Primary Examiner(s): Levin, Naum B
• Application Number:
  US14/086,306
• Publication Number:
  US 20140159666A1
• Time in Patent Office: 1,020 Days
• US Class Current: 1/1
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

Even when current values of a current that flows to a plurality of cell modules connected in parallel are different, efficient charging is performed. A charge control device that controls a charging current to be supplied to a plurality of cell modules connected in parallel compares a maximum current value, selected from current values detected by a current sensor provided in each of a plurality of the cell modules, with a reference current value predetermined as a maximum current value of the current to be supplied to secondary batteries, and controls the charging current to be supplied to a plurality of the cell modules based on a comparison result.

Claims

1. A charge control device that controls a charging current to be supplied to a plurality of chargeable and dischargeable cell modules connected in parallel, wherein

the charge control device performs:

a selecting operation that selects the maximum value as a maximum current value from current values detected by a current sensor provided in each of a plurality of the cell modules;

a comparing operation that compares the maximum current value which is selected with a reference current value predetermined as a maximum current value of the current to be supplied to the cell modules; and

an increasing/decreasing operation that increases or decreases, on the basis of a comparison result of the comparing operation, the charging current to be supplied to a plurality of the cell modules by a predetermined specified value,

wherein the charge control device repeatedly performs the selecting operation, the comparing operation and the increasing/decreasing operation until the maximum current value which is selected becomes the same value as the reference current value.

2. The charge control device according to claim 1, wherein

when the maximum current value is less than the reference current value, the charging current is increased, whereas when the maximum current value exceeds the reference current value, the charging current is decreased.

3. The charge control device according to claim 1, wherein

when at least one voltage value, detected by a voltage sensor that detects a voltage in each of secondary batteries that constitute the cell modules, has reached a predetermined first upper limit, the charging current to be supplied to the cell modules is controlled so that a maximum voltage value detected by the voltage sensor does not exceed a predetermined second upper limit.

4. The charge control device according to claim 3, wherein

charging of the cell modules is ended based on the current values detected by the current sensors.

5. The charge control device according to claim 1, wherein

a plurality of the current sensors are provided in different positions for each of the cell modules, and

the presence or absence of abnormality is determined based on a difference in detection results by a plurality of the current sensors provided for each of the cell modules.

6. The charge control device according to claim 1, wherein

the presence or absence of abnormality is determined based on a difference in detection results in each of the cell modules detected by the current sensor.

7. A cell system, comprising:

a plurality of chargeable and dischargeable cell modules connected in parallel;

a power source that supplies a charging current to a plurality of the cell modules;

a plurality of current sensors that detect the current in each of a plurality of the cell modules; and

the charge control device according to claim 1.

8. A charge control method for controlling a charging current that is supplied to a plurality of chargeable and dischargeable cell modules connected in parallel, comprising:

a first step of selecting the maximum value as a maximum current value selected from current values detected by a current sensor in each of a plurality of the cell modules;

a second step of comparing the maximum current value which is selected with a reference current value predetermined as a maximum current value of the current to be supplied to the cell modules; and

a third step of increasing or decreasing, on the basis of a comparison result of the second step, the charging current to be supplied to a plurality of the cell modules by a predetermined specified value,

wherein the first step, the second step and the third step are repeatedly performed until the maximum current value which is selected becomes the same value as the reference current value.