abstract |
Methods and systems are provided for estimating and extending the expected cell cycling lifetime for produced lithium ion cells. Methods comprise monitoring charging and/or discharging peak(s) during formation cycles of the cells, which are defined with respect to dQ/dV measurements during the formation cycles, and ending the formation process once the charging and/or discharging peaks disappear, optionally deriving the expected cell cycling lifetime by comparing the monitored peaks to specified thresholds that are correlated to the lifetime. The methods may be implemented by controller(s) at the battery, device and/or factory levels, which may be operated in combination. Formation processes and/or cell operation schemes may be adjusted accordingly, to avoid excessive dQ/dV rates and increase thereby the cell cycling lifetime. |