Patent ID: 9678165
Date: 2017-06-13
CPC Classifications: G01R,H01M,Y02E

Claim:
1. An apparatus for estimating a depth of discharging (DOD) of a secondary battery, comprising: a sensor unit configured to repeatedly measure a voltage of a secondary battery including a blended cathode material containing at least first and second cathode materials at time intervals when the secondary battery is in an operation state or in an idle state; and a control unit configured to: receive the repeatedly measured plurality of voltages from the sensor unit, identify an inflection point indicative of changing of a cathode material reacting with working ions in a voltage change over time profile corresponding to the plurality of voltages, measure a voltage a predetermined time after the inflection point, and estimate a DOD of the secondary battery by using the voltage measured after the inflection point is identified as a reference voltage.