Method for controlling the end of the discharge of a rechargeable battery

• US 20090278502A1
• Filed: 10/05/2007
• Published: 11/12/2009
• Est. Priority Date: 10/13/2006
• Status: Active Grant

• Current Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Original Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Inventors: Delaille, Arnaud, Perrin, Marion
• Granted Patent: US 8,159,190 B2
• Time in Patent Office: Days
• US Class Current: 320/136
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/005 Detection of state of health [SOH]

Abstract

The method for controlling the end of discharge of a rechargeable battery according to the invention comprises determining (F1) the transition frequency (F_HF) of the battery and determining (F2, F3) an end-of-discharge criterion of the battery according to said transition frequency (F_HF). Said end-of-discharge criterion is representative for example of a predetermined maximum value (Pmax) of the slope of the transition frequency (F_HF). The transition frequency (F_HF) can be determined (F1) periodically during use of the battery, discharging being interrupted (F4) by regulating means according to said transition frequency (F_HF).

Claims

1. A method for controlling the end of discharge of a rechargeable battery, comprising determining the transition frequency of the battery and determining an end-of-discharge criterion of the battery according to said transition frequency.

2. The method according to claim 1, wherein the transition frequency is determined periodically during use of the battery, discharging being interrupted regulating means according to said transition frequency.

3. The method according to claim 1, wherein said end-of-discharge criterion is determined from measurements of the transition frequency made during a calibration phase.

4. The method according to claim 1, wherein said end-of-discharge criterion is readjusted from measurements of the transition frequency made during a maintenance phase.

5. The method according to claim 3, wherein said end-of-discharge criterion is constituted by the voltage at the battery terminals.

6. The method according to claim 2, wherein said end-of-discharge criterion is representative of a sudden change of slope of the transition frequency in the course of discharging.

7. The method according to claim 2, wherein said end-of-discharge criterion is representative of a predetermined maximal value of the transition frequency.

8. The method according to claim 2, wherein said end-of-discharge criterion is representative of a predetermined maximal value of the slope of the transition frequency.