Method and system for energy storage capacity estimation of battery cells

摘要

An apparatus (100) includes at least one electrochemical cell (106) and at least one pass element (104) serially coupled with the electrochemical cell. A control circuit (102) is operable to open the at least one pass element when a charger (105) or power supply (107) is connected to the electrochemical cell for at least a predetermined time and to measure an open circuit voltage of the at electrochemical cell to determine a state of charge. The control circuit can then close the pass element to charge the electrochemical cell, determine an amount of the charge, and store an estimated energy capacity of the electrochemical cell based upon the open circuit voltage and the amount.

主权项

1. A method of estimating cell capacity, comprising:
detecting a charger coupled to a charging terminal of a battery; in response to detecting the charger coupled to the charging terminal, and prior to opening a circuit coupled serially between the one or more cells of the battery and the charging terminal, determining an initial state of charge of the one or more cells; determining that the initial state of charge is within a predefined range; in response to determining that the initial state of charge prior to the opening is within a predefined range:
opening the circuit coupled serially between the one or more cells of the battery and the charging terminal prior to the charger charging the one or more cells;measuring, with a control circuit, an open circuit voltage of the one or more cells to determine a state of charge of the one or more cells;after the measuring, closing the circuit to permit charging of the one or more cells by the charger;determining an amount of the charging occurring after the closing; andestimating an energy storage capacity of the one or more cells from the amount of the charging and the state of charge.