A Modular, Scalable Battery Management System

Grid Battery Controller

For large-scale multi-stack battery configurations, the GBC manages all cells and stacks across the entire battery and enables remote monitoring, management, and maintenance of the battery from a single device. Configured in compliance with MESA (Modular Energy Storage Architecture) Open Standards for Energy Storage, the GBC is designed specifically for integration with utility-scale batteries and inverters.

  • Collects pack-level voltage, temperature, and current statistics for all cells, SOC and SOH, system-wide faults, warnings, and battery pack diagnostics for the entire battery
  • Provides a single entry point to all measurement and control points in the BMS
  • Ensures that measurements, control signals, and other data are propagating properly through the entire system
  • Streams real-time data to external servers for analytics and trend data capture
  • Multi-socket Ethernet interface allows concurrent operation of both local and remote operator panels, data analytics streaming, and Modbus TCP inverter control
  • MESA-compliant Modbus TCP for connection to power conversion systems
  • Assigns IP addresses to stack controllers automatically to simplify battery bring-up
  • Pushes firmware and configuration updates to all BMS modules across entire battery

Stack Controller

The Stack Controller monitors and controls all Cell Interfaces in a single battery stack. The built-in Stack Bus receives power and communication from the Power Interface. The Link Bus provides power and communication for all connected Cell Interfaces. Ethernet, CAN, and RS-485 (Modbus RTU) connections are included. No high-voltage or high-current interfaces are present on the Stack Controller, making this module easy and safe to connect to for service operations.


  • Master controller for the BMS stack
  • Communicates with systems outside of the BMS via Modbus TCP (Ethernet), Modbus RTU (RS-485), or CAN bus
  • Provides State of Charge and State of Health tracking
  • Supports firmware upgrades via Ethernet
  • Includes Link Bus interface to Cell Interface module(s)
  • Includes Stack Bus interface to Power Interface module
  • LEDs provide Power, Activity, and Fault status


Cell Interface

The Cell Interface connects to the battery cells and temperature sensors to monitor and balance the cells and sends cell data to the Stack Controller to prevent overheating, overcharging, and overdischarging. Communication and power are provided over the Link Bus.


  • Stackable architecture supports using multiple Cell Interfaces to support hundreds of cells in series
  • Includes internal temperature monitoring of the module plus 8 external sensor inputs for the cells
  • Galvanically isolated serial communications between Cell Interfaces and the Stack Controller protect the system from electromagnetic interference and enable floating battery architectures and highly accurate voltage readings
  • Up to 60 VDC per Cell Interface Provides passive balancing up to 300mA
  • Daisy chain architecture; no addressing switches to set
  • LEDs provide Activity and Fault status
  • Monitors voltage of each cell
  • A single module manages up to 12 or 16 cells (depending on the model)

Power Interface

The Power Interface connects directly to high-voltage and high-current components. It provides system power from either the battery stack or external power inputs, power conditioning for all Nuvation BMS™ modules, and power for the contactors. The Stack Controller controls all operations on the Power Interface via the Stack Bus.


  • Provides operating power for the system, sourced from the battery stack or sourced from a 24 VAC/VDC input, which allows full functionality even with fully discharged battery cells
  • Monitors stack current via an external temperature-compensated inline current shunt for high accuracy
  • Monitors battery stack voltage
  • External equipment interlock connector provides contactor enable and E-stop contactor disconnect functions
  • LEDs provide Power, Activity, and Fault status
  • Includes coil drivers for 4 contactors; 24 VDC provided for contactor coils, optional external coil power input for voltage flexibility