Battery SoH Monitoring Protocol for Underground LHDs (Field Manual + Sensor Calibration Guide)

Battery SoH monitoring for underground LHDs addresses the unique challenges of subterranean operations: extreme temperature gradients (4°C–45°C), high humidity, dust ingress, electromagnetic interference from blasting and VFD drives, and constrained wireless communication. Unlike surface applications, underground SoH estimation cannot rely solely on cloud-based AI models; instead, it employs edge-computing-capable onboard controllers that fuse voltage, current, temperature (multi-point), impedance spectroscopy (at discrete frequencies), and coulombic efficiency data using physics-informed algorithms. The protocol mandates periodic in-situ sensor recalibration using NIST-traceable reference cells and shunt-based current verification under controlled load profiles (e.g., standardized 30-min ramped discharge cycles), compensating for drift induced by vibration, thermal cycling, and connector oxidation. Calibration intervals are dynamically adjusted based on accumulated mechanical shock (measured via embedded accelerometers) and electrolyte aging indicators (e.g., rising internal resistance slope >2.5%/1000 cycles). Field operators follow tiered diagnostic workflows—from Level-1 visual/auditory anomaly checks (e.g., cell venting signs, thermal camera hotspots >65°C) to Level-3 lab-grade impedance validation—ensuring compliance with MSHA and ISO 12100 functional safety requirements for BEME.