BMS

The Battery Management System (BMS) is the authoritative controller for every traction pack. It monitors cell voltages and temperatures, enforces charge and discharge limits, manages contactors, estimates SOC and SOH, and communicates pack status to the vehicle controller and external chargers — including wireless power receivers.

SiCore wireless charging never bypasses the BMS. The receiver requests charge permission; the BMS grants current within cell-level constraints. This boundary is non-negotiable for safety certification and pack warranty compliance.

01Core BMS functions

• Cell voltage monitoring: per-cell or group sensing with over/under-voltage protection and shutdown.
• Current sensing: shunt or Hall-effect measurement for coulomb counting and overcurrent protection.
• Thermal management: cell and FET temperature inputs driving fan, pump, or derating requests.
• Contactor and pre-charge control: safe connection/disconnection of HV bus to vehicle inverter.
• Isolation monitoring: detects ground faults between HV pack and chassis.

02Charge control interface

During wireless charging the BMS exposes charge permission, maximum charge current, and charge voltage limit on CAN (or equivalent). The onboard charger or DC charge controller — fed by the wireless receiver — regulates output to stay within BMS setpoints. If any cell approaches over-voltage or over-temperature during charge, the BMS reduces the current request or opens contactors, and the SiCore transmitter ramps down via the same communication path.

03Diagnostics and fleet integration

BMS fault codes — cell imbalance, sensor failure, contactor weld, thermal runaway warning — must propagate to fleet software and pad controllers. SiCore integrations map standard BMS DBC signals so charge sessions abort cleanly on fault rather than leaving the transmitter energized against an open contactor. BMS firmware versioning is tracked per vehicle for field update coordination.