US 9,812,877 B2 | ||
Charge redistribution method for cell arrays | ||
Ioannis Milios, New York, NY (US) | ||
Assigned to Sendyne Corporation, New York, NY (US) | ||
Filed by Sendyne Corporation, New York, NY (US) | ||
Filed on Feb. 18, 2015, as Appl. No. 14/625,270. | ||
Application 13/926,057 is a division of application No. 13/510,935, abandoned, previously published as PCT/IB2011/054789, filed on Oct. 27, 2011. | ||
Application 14/625,270 is a continuation of application No. 13/926,057, filed on Jun. 25, 2013, abandoned. | ||
Claims priority of provisional application 61/408,505, filed on Oct. 29, 2010. | ||
Prior Publication US 2015/0222133 A1, Aug. 6, 2015 | ||
Int. Cl. H02J 7/00 (2006.01); H01M 10/44 (2006.01) |
CPC H02J 7/0021 (2013.01) [H01M 10/441 (2013.01); H02J 7/007 (2013.01); H02J 7/0014 (2013.01)] | 5 Claims |
1. A method for use with a series array of a plurality of electrochemical cells, each cell having a respective state of charge,
the method comprising the steps of:
measuring discharge current during a first measurement interval, said current measurement during the first measurement interval
carried out across a predetermined bandwidth;
measuring cell terminal voltage for a first one of the cells during the first measurement interval, said voltage measurement
during the first measurement interval carried out across the predetermined bandwidth;
measuring discharge current during a second measurement interval, said current measurement during the second measurement interval
carried out across a predetermined bandwidth;
measuring cell terminal voltage for a second one of the cells during the second measurement interval, said voltage measurement
during the second measurement interval carried out across the predetermined bandwidth;
deriving information indicative of a respective effective internal impedance for each of the first one of the cells and the
second one of the cells, said derived effective internal impedance having not only a pure ohmic component but also frequency
dependent component, said derived effective internal impedance defining a magnitude greater than that of the pure ohmic component
taken alone;
deriving information indicative of a respective effective internal cell voltage for each of the first one of the cells and
the second one of the cells;
monitoring a signal frequency of a load current delivered by the series array of a plurality of electrochemical cells to a
load;
determining a relationship between the signal frequency of the load current and the respective state of charge of each cell,
and thereby identifying a particular one of the first one of the cells and the second one of the cells having a lower effective
internal cell voltage and a higher magnitude of effective internal impedance; and
topping up the state of charge of the identified cell.
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