Lithium Ion Battery Cell having a Capacitance Sensor and Method for Monitoring the Condition of a Lithium Ion Battery Cell of this Type

A lithium ion battery cell includes a graphite cathode, and an excess pressure valve. The excess pressure valve is configured to open in the presence of a predetermined battery cell internal pressure and discharging gases that have been produced inside the battery cell. Such gases are discharged together with graphite particles entrained in the gas. The battery cell further includes a capacitance sensor that has at least one capacitor positioned in the battery cell and configured such that the graphite particles that are entrained in the gas that is being discharged deposit themselves at least in part in a gap that is located between two electrodes of the capacitor and cause a change in the dielectric value in the gap. The change in the dielectric value causes a change in a capacitance of the capacitor.