Method of battery charge restoration based on estimated battery plate deterioration and/or based on battery state of health

• US 6,362,601 B1
• Filed: 11/17/2000
• Issued: 03/26/2002
• Est. Priority Date: 11/17/2000
• Status: Expired due to Term

• Current Assignee: Curtis Instruments Incorporated
• Original Assignee: Curtis Instruments Incorporated
• Inventors: Finger, Eugene P.
• Primary Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US09/716,116
• Time in Patent Office: 494 Days
• Field of Search: 320/153, 320/162, 324/426
• US Class Current: 320/153
• CPC Class Codes: G01R 31/379 for lead-acid batteries
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/0032 disconnection of loads if battery is not under charge, e.g. in vehicle if engine is not running

Abstract

In one preferred embodiment of the invention, a method of restoring charge to a battery operating with a predetermined terminal voltage, including: determining an expected rate of degradation of a plate or plates of a battery in terms of decrease of capacity per unit time and temperature of operation of the battery to determine a degree of degradation of capacity of the battery; and providing sufficient charge to the battery to restore a predetermined degree of the capacity of the battery. In another preferred embodiment of the invention, a method of diagnosing state of health of a battery, including: restoring a theoretical amount of charge to a partially depleted battery; and examining how the battery responded to the step of restoring a theoretical amount of charge to the partially depleted battery to determine the state of health of the battery.

Claims

1. A method of restoring charge to a battery operating with a predetermined terminal voltage, comprising:

(a) determining an expected rate of degradation of a plate or plates of said battery in terms of decrease of capacity per unit time and temperature of operation of said battery to determine a degree of degradation of capacity of said battery; and

(b) providing sufficient charge to said battery to restore a predetermined degree of said capacity of said battery.

2. A method of restoring charge to a battery, as defined in claim 1, further comprising:

multiplying said rate of degradation of said battery by a factor representative of calendar age of said battery.

3. A method of restoring charge to a battery, as defined in claim 1, further comprising:

multiplying said rate of degradation of said battery by a factor representative of degrees of discharge to which said battery has been subjected.

4. A method of restoring charge to a battery, as defined in claim 1, wherein:

(a) said predetermined voltage is selected such that there is minimal positive plate corrosion with concomitant negative plate discharge; and

(b) said rate of degradation is rate of self-discharge of said negative plate.

5. A method of restoring charge to a battery, as defined in claim 1, further comprising:

measuring charge restoration response during said step of providing sufficient charge to said battery.

6. A method of restoring charge to a battery, as defined in claim 5, further comprising:

adjusting said step of providing sufficient charge to said battery based on said charge restoration response.

7. A method of restoring charge to a battery, as defined in claim 6, wherein:

said step of measuring charge restoration response includes determining if terminal voltage of said battery falls within a predetermined range based on length of charge.

8. A method of restoring charge to a battery, as defined in claim 1, wherein:

said battery is provided as back-up battery in a float charging system.

9. A method of restoring charge to a battery, as defined in claim 1, wherein:

said battery remains on-line during said step of providing sufficient charge.