Battery Management System Modules

The Nuvation Energy battery management system family consists of modular blocks that can be assembled in various configurations to meet different system requirements. In the Stack Switchgear and Multi-Stack Controller we have pre-integrated one or more of these modules into higher-level battery control systems, to reduce your system integration effort. The Stack Switchgear includes one Power Interface and one Stack Controller. All modules can be purchased separately.

User manuals and technical data sheets are available for download on our Technical Resources page.

Stack Switchgear (SSG)

Nuvation Energy Stack Switchgear protects the cells in a high-voltage battery stack and manages the Cell Interface modules that connect directly to the cells. It connects and disconnects a battery stack to the DC Bus, and provides connectivity between the batteries and higher level ESS controllers.

• Includes all components required to connect the stack to the DC bus, i.e. fuses, contactors, bus bars, current shunts, pre-charge circuits, e-stop, short-circuit protection, and networking.
• Calculates State of Charge (SOC) and Depth of Discharge (DOD) and uses voltage and temperature data from the BMS to dynamically adjust recommended current thresholds provided to the PCS. Current limiter feature helps prevent overcharge and over-discharge by scaling back current thresholds as the batteries approach max SOC and DOD.
• Reports available capacity changes to the PCS and other ESS managers.
• Provides terminal connections for the battery stack as well as communications I/O for other ESS controllers.
• Provides cell balancing commands to Cell Interface modules during the charge cycle.
• Executes safety disconnect commands to protect the battery if the cells are performing outside of their safety profile. Also includes short-circuit protection.
• Can control battery rack cooling fans in response to temperature rise data from Cell Interface modules.

Power Interface

The Power Interface module is located inside the Stack Switchgear unit, and can be sold separately for systems that do not employ Stack Switchgear. It measures stack current and provides power to other High-Voltage BMS modules.

• Provides operating power for the system, sourced from a 24 VAC/VDC input. This allows full functionality even with fully discharged battery cells.
• Measures stack current via a current shunt.
• Measures stack voltage.
• Includes coil drivers for up to four contactors. Provides 24 VDC power for energizing contactor coils, and can include an optional external coil power input to provide voltage flexibility.
• LEDs provide Power, Activity, and Fault status.

Stack Controller

The Stack Controller is the master controller of all BMS modules in a battery stack. It is located inside the Stack Switchgear unit, and can be sold separately for systems that do not employ Stack Switchgear.

• Connects to Cell Interface modules to manage balancing and provide stack management.
• Calculates State of Charge and Depth of Discharge at both the cell and stack levels.
• Communicates with external systems via Modbus TCP (Ethernet), Modbus RTU (RS-485), or CAN bus.
• Provides access to the Nuvation Energy BMS Operator Interface.
• 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 module can be used in both low- and high-voltage battery stacks. It measures voltage and temperature, and provides cell balancing. In a high-voltage battery stack, multiple Cell Interface modules manage series-connected cells to reach voltages of up to 1250 VDC. For low-voltage applications, one Cell Interface module can be added to the Low-Voltage BMS to increase the number of series-connected cells in an 11-60 VDC stack.

• Measures the voltage and temperature of each cell and provides cell balancing.
• Connects directly to cells. Includes up to eight external temperature sensor inputs for the cells (seven in UL 1973 applications).
• 12- and 16-channel models available. Also available 4-channel model designed specifically for 12 V monobloc cells (these are usually lead-acid cells).
• Provides passive balancing up to 300mA (12- and 16-channel models only).
• Stackable architecture enables multiple Cell Interface modules to be used in each battery stack to connect hundreds of cells in series.
• Galvanically isolated serial communications between Cell Interface modules and the Stack Controller protect the system from electromagnetic interference and enable floating battery architectures and highly accurate voltage readings.
• Each Cell Interface can manage up to 80 VDC.
• Daisy chain architecture; no addressing switches to set.
• LEDs provide Activity and Fault status.

Low-Voltage Battery Management System

The Low-Voltage BMS is the equivalent of a Power Interface, Stack Controller, and Cell Interface module in one package. It is used in energy storage applications with a maximum voltage of up to 60 VDC. It also supports the periodic peak voltages of up to 68 VDC that can occur during battery maintenance operations such as lead battery equalization (but it is not designed for continuous operation above 60 Volts).

• One Low-Voltage Battery Management System manages one stack.
• 12- and 16-channel (i.e. single cells or cell groupings for increased capacity) models are available.
• Can manage additional cells in series by adding additional Cell Interface modules (maximum overall stack voltage of 60 VDC still applies).
• Parallel stack management is available by adding a Multi-Stack Controller.
• Provides cell balancing for lithium-ion and other battery chemistries, and can be used with lead-acid batteries as well.
• Communicates with systems outside of the BMS via Modbus TCP (Ethernet), Modbus RTU (RS-485), or CAN bus.

Multi-Stack Controller

The Multi-Stack Controller aggregates all the battery stacks in your energy storage system. It enables operation of the overall system as a unified battery and provides stack-level information and control.

• Enables monitoring and control of the entire battery pack though a single Modbus TCP interface.
• Collects pack-level voltage, temperature, and current statistics for all cells.
• Calculates State of Charge and Depth of Discharge of the unified energy storage system.
• Aggregates system-wide faults and warnings and provides battery pack diagnostics.
• Ensures that measurements and control signals are propagating though all BMS modules.
• Functions as a data analytics gateway by providing access to battery measurements for data capture.
• Available dedicated Ethernet port for energy controller activity.
• Wall mountable, with optional rack-mount form factor.
• Includes 10G SFP+ ports, enabling optional fiber optic networking.
• Positive-lock power supply connector.
• Designed to meet the requirements of SAE J2464 (shock) and SAE J2380 (random vibration).