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Title: Equalizer system and method for series connected energy storing devices

Abstract

An apparatus and method for regulating the charge voltage of a number of electrochemical cells connected in series is disclosed. Equalization circuitry is provided to control the amount of charge current supplied to individual electrochemical cells included within the series string of electrochemical cells without interrupting the flow of charge current through the series string. The equalization circuitry balances the potential of each of the electrochemical cells to within a pre-determined voltage setpoint tolerance during charging, and, if necessary, prior to initiating charging. Equalization of cell potentials may be effected toward the end of a charge cycle or throughout the charge cycle. Overcharge protection is also provided for each of the electrochemical cells coupled to the series connection. During a discharge mode of operation in accordance with one embodiment, the equalization circuitry is substantially non-conductive with respect to the flow of discharge current from the series string of electrochemical cells. In accordance with another embodiment, equalization of the series string of cells is effected during a discharge cycle.

Inventors:
 [1];  [2];  [3];  [4];  [5];  [6]
  1. Saint-Luc, CA
  2. Montreal, CA
  3. Stillwater, MN
  4. Vadnais Heights, MN
  5. Longueuil, CA
  6. Beloeil, CA
Issue Date:
Research Org.:
United States Advanced Battery Consortium, Dearborn, MI (US)
OSTI Identifier:
872518
Patent Number(s):
5952815
Assignee:
Minnesota Mining & Manufacturing Co. (St. Paul, MN); Hydro-Quebec Corporation (Montreal, CA)
Patent Classifications (CPCs):
H - ELECTRICITY H02 - GENERATION H02J - CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER
DOE Contract Number:  
FC02-91CE50336
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
equalizer; method; series; connected; energy; storing; devices; apparatus; regulating; charge; voltage; electrochemical; cells; disclosed; equalization; circuitry; provided; control; amount; current; supplied; individual; included; string; interrupting; flow; balances; potential; pre-determined; setpoint; tolerance; charging; prior; initiating; cell; potentials; effected; cycle; throughout; overcharge; protection; coupled; connection; discharge; mode; operation; accordance; embodiment; substantially; non-conductive; respect; series string; discharge current; storing device; series connected; electrochemical cells; electrochemical cell; energy storing; series connection; overcharge protection; charge cycle; charge voltage; storing devices; connected energy; current supplied; discharge cycle; cells connected; charge current; cell potential; /320/

Citation Formats

Rouillard, Jean, Comte, Christophe, Hagen, Ronald A, Knudson, Orlin B, Morin, Andre, and Ross, Guy. Equalizer system and method for series connected energy storing devices. United States: N. p., 1999. Web.
Rouillard, Jean, Comte, Christophe, Hagen, Ronald A, Knudson, Orlin B, Morin, Andre, & Ross, Guy. Equalizer system and method for series connected energy storing devices. United States.
Rouillard, Jean, Comte, Christophe, Hagen, Ronald A, Knudson, Orlin B, Morin, Andre, and Ross, Guy. Fri . "Equalizer system and method for series connected energy storing devices". United States. https://www.osti.gov/servlets/purl/872518.
@article{osti_872518,
title = {Equalizer system and method for series connected energy storing devices},
author = {Rouillard, Jean and Comte, Christophe and Hagen, Ronald A and Knudson, Orlin B and Morin, Andre and Ross, Guy},
abstractNote = {An apparatus and method for regulating the charge voltage of a number of electrochemical cells connected in series is disclosed. Equalization circuitry is provided to control the amount of charge current supplied to individual electrochemical cells included within the series string of electrochemical cells without interrupting the flow of charge current through the series string. The equalization circuitry balances the potential of each of the electrochemical cells to within a pre-determined voltage setpoint tolerance during charging, and, if necessary, prior to initiating charging. Equalization of cell potentials may be effected toward the end of a charge cycle or throughout the charge cycle. Overcharge protection is also provided for each of the electrochemical cells coupled to the series connection. During a discharge mode of operation in accordance with one embodiment, the equalization circuitry is substantially non-conductive with respect to the flow of discharge current from the series string of electrochemical cells. In accordance with another embodiment, equalization of the series string of cells is effected during a discharge cycle.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1999},
month = {1}
}