Method and apparatus with battery state estimation

A processor-implemented method with battery state estimation, comprising:

• determining a state variation of a virtual battery corresponding to a target battery that is discharged to reach a preset voltage, using a voltage difference between an estimated voltage that is estimated by an electrochemical model corresponding to the virtual battery and a preset voltage;
• updating an internal state of the electrochemical model based on the determined state variation of the virtual battery;
• and
• estimating an end state of charge (SOC) of the target battery by estimating state information of the virtual battery based on the updated internal state of the electrochemical model.

An apparatus with battery state estimation, comprising:

• a memory configured to store a first electrochemical model corresponding to a target battery and a second electrochemical model based on a virtual battery corresponding to the target battery being discharged to reach a preset voltage;
• and
• a processor configured to:
• estimate a current state of charge (SOC) of the target battery by correcting the first electrochemical model using a voltage difference between a measured voltage of the target battery and an estimated voltage of the target battery that is estimated by the first electrochemical model;
• estimate an end SOC of the target battery by correcting the second electrochemical model using a voltage difference between an estimated voltage of the virtual battery that is estimated by the second electrochemical model and the preset voltage;
• and
• estimate the RSOC of the target battery based on the current SOC and the end SOC of the target battery.