Do I still need discharge testing if I have monitoring?

Yes, and this is where most monitoring vendors overclaim. Impedance and conductance are trend indicators, not capacity measurements. They catch open cells, dry-out and connection faults, and rising impedance correlates with capacity fade, but the only direct measure of capacity is a timed discharge test. AusNet’s own asset strategy states that the impracticality of discharge testing on single-bank zone substations “prevent[s] accurate measurement of the DC system available capacity”, which is why they pursue continuous cell monitoring and a capacity test method. /is-battery-monitoring-worth-the-cost/