Method for controlling a cell current limiting value for a battery management system, battery management system

A battery management systemconfigured to control a cell current limiting value for a battery management system, by:

• determining quadratic reference currents iref2 of a battery cell (34), at a measured temperature Tsens, for different time intervals tref,
• calculating a corresponding reference time constant τref for each reference current iref by the application of a model for the calculation of a RMS value iRMS of a cell current ireq by reference to a continuous current icont, which corresponds to the minimum current in the charging or discharging device which causes no thermal damage;
• constituting a diagram for the relationship between the reference time constant τref and the quadratic reference current iref2, by reference to the calculated reference time constants τref and the quadratic reference currents iref2 determined for each specific temperature T;
• determining a predictive time constant τpred by the comparison of a quadratic measured value isens2 of a cell current ireq with the quadratic reference currents iref2;
• and
• calculating a predictive RMS limiting value ipred of the cell current ireq, on the basis of the continuous current icont, a predictive time tpred and the predictive time constant τpred.

A battery having one or more battery cells (34), where in the battery is configured to control a cell current limiting value for a battery management system, by:

• determining quadratic reference currents iref2 of a battery cell (34), at a measured temperature Tsens, for different time intervals tref,
• calculating a corresponding reference time constant τref for each reference current iref by the application of a model for the calculation of a RMS value iRMS of a cell current ireq by reference to a continuous current icont, which corresponds to the minimum current in the charging or discharging device which causes no thermal damage;
• constituting a diagram for the relationship between the reference time constant τref and the quadratic reference current iref2, by reference to the calculated reference time constants τref and the quadratic reference currents iref2 determined for each specific temperature T;
• determining a predictive time constant τpred by the comparison of a quadratic measured value isens2 of a cell current ireq with the quadratic reference currents iref2;
• and
• calculating a predictive RMS limiting value ipred of the cell current ireq, on the basis of the continuous current icont, a predictive time tpred and the predictive time constant τpred.

A vehicle comprising a battery management system configured to

• determine quadratic reference currents iref2 of a battery cell (34), at a measured temperature Tsens, for different time intervals tref,
• calculate a corresponding reference time constant τref for each reference current iref by the application of a model for the calculation of a RMS value iRMS of a cell current ireq by reference to a continuous current icont, which corresponds to the minimum current in the charging or discharging device which causes no thermal damage;
• constitute a diagram for the relationship between the reference time constant τref and the quadratic reference current iref2, by reference to the calculated reference time constants τref and the quadratic reference currents iref2 determined for each specific temperature T;
• determine a predictive time constant τpred by the comparison of a quadratic measured value isens2 of a cell current ireq with the quadratic reference currents iref2, and
• calculate a predictive RMS limiting value ipred of the cell current ireq, on the basis of the continuous current icont, a predictive time tpred and the predictive time constant τpred.