Method and system for charging a NiMH or NiCd battery

• US 20040135551A1
• Filed: 08/13/2003
• Published: 07/15/2004
• Est. Priority Date: 04/19/2001
• Status: Active Grant

• Current Assignee: Schneider Electric IT Corporation (Schneider Electric SE)
• Original Assignee: American Power Conversion Corporation (Schneider Electric SE)
• Inventors: Hoff, C. Michael, Nelson, James E.
• Granted Patent: US 7,129,676 B2
• Time in Patent Office: Days
• US Class Current: 320/150
• CPC Class Codes: H02J 9/062 for AC powered loads

Abstract

A method of charging a NiMH or NiCd battery such that charging does not occupy a substantial amount of time and such that the operating temperature of the battery is reduced during the lifetime of the battery, thereby extending the life of the battery. This invention is a method of charging that is accomplished using a temperature differential method to continuously regulate the rate of charge injected into the battery. An amplifier is used to amplify the difference in temperature between one or more cases in which the battery is contained and ambient temperature. In this method, the greater the difference in temperature, the lower the charging current is injected into the battery. The method of charging may be incorporated into uninterruptible power supply equipment.

Claims

1. A method of charging a battery comprising:

providing at least one of a Nickel Metal Hydride battery and;

a Nickel Cadmium battery;

sensing a first temperature at a point proximal to the battery;

sensing a second temperature at a point distal to the battery;

controlling current into the battery according to a difference between the first temperature and the second temperature.

2. The method of claim 1, wherein the at least one battery is incorporated into an uninterruptible power supply.