Battery measurement

A rechargeable battery assembly comprising:

• a battery module comprising a plurality of cell units connected in series between a first terminal and a second terminal;
• a current shaping assembly selectively couplable to a current path through the battery module;
• and
• a measurement subsystem arranged to carry out a measurement procedure in a course of operation of the rechargeable battery assembly the measurement procedure comprising the measurement subsystem arranged to:
• couple the current shaping assembly to said current path and operate the current shaping assembly to vary an electric current in said current path over a measurement period according to a switching sequence defined by a multi-frequency pseudo-random pulse sequence (PRPS) that represents a plurality of frequency components at a predefined frequency resolution within a predefined frequency range and that defines switching between different current levels as a function of time,
• obtain measurement data that comprises a respective indication of a respective cell-unit-specific voltage across each cell unit of the plurality of cell units as a function of time and an indication of the electric current in said current path as a function of time over the measurement period,
• derive a respective cell-unit-specific impedance of each cell unit based on the measurement data, and
• determine, based on the derived impedances, at least one status indication that pertains to a condition of the battery module.