Battery Control Unit

Battery and Energy Management Systems

Leclanché offers multiple BMS technologies and a suite of Energy Management Systems software. BMS are an integral part of Leclanché’s high voltage (e-Transport, Stationary) and low voltage systems solutions while the EMS software suite offers cutting-edge tools to manage large grid-connected Battery Energy Storage Systems.

Battery Management Systems (BMS)

Leclanché develops its own in-house BMS, in partnership with a hardware company. All BMS are either master-slave or single board architecture. BMS commonly provide software and hardware safety for overcharge/ deep discharge, over/under voltage, over current, over/under temperature, pre-charge, short circuit and other protection. They have built-in technology and specific algorithms such as SOC, SOH, cell/ module balancing and real time control over charge/ discharge current. They also have the capability to indicate performance and monitor control parameters. A user-friendly Graphical User Interface (GUI) provides system performance and diagnostics for the system.  BMS provide CAN and RS485 communication ports to connect to the host/ higher layer system. Download technical data sheet.

High voltage BMS

Leclanché offers two high voltage BMS with 1000-V isolation: G2 for e-Transport solutions, and A1 for stationary solutions.  Both have master-slave architecture and comply with design and industry safety standards. BMS offer pre-charge control, contactor control, and emergency stop and override control with system isolation fault monitoring.

BMS for e-Transport solutions

To learn more about our e-Transport solutions, click here.

The e-Transport BMS consists of three parts:

  • Master: the main BMS controller – BCU
  • Slave: the module measurement units – BMU
  • The contactor module – the switch box

Master – BCU

The BCU is the central control unit that monitors and controls the status of the batteries, including system charging, discharging and host communication. The BCU can be configured and integrated into the customer battery system via CAN or serial communication interfaces.

Slave – BMU

The BMU is the local voltage and temperature measurement unit for the battery modules. It sits in the module. The BMU monitors up to 12 or 24 individual cell voltages and up to 2 to 4 cell group temperatures depending on the model. The measurements are transmitted to the BCU via the internal RS485 BUS. The BMU also contains passive cell balancing circuitry controlled by the BCU to bring all cells in the module and battery to equal capacity. Multiple BMUs can be daisy-chained for a maximum system voltage of 1000VDC.

BMS data communication architecture and diagnostics tool

A diagnostics tool provides system and cell level information, error handling, master and slave firmware updates, system configuration and parameter management, signal logging and visualisation.

BMS for stationary solutions

To learn more about our stationary solutions, click here.

Leclanché’s stationary business offers solutions for small (500kWh) to mid-size (50MWh) grid connected, microgrid, solar/wind integrated and behind the meter energy storage systems. We provide stationary racks with LTO and NMC- G cell technology and complete system container with inverter partners.

The complete BMS, or string controller (Storage Rack System), has master and slave architecture and consists of the following:

  • Master SRC2 (Storage Rack Controller): Control unit of the battery storage system and separator for disconnecting the battery voltage to the outside if necessary
  • Slave: SRB (Storage Rack Battery): Battery module with integrated
    battery management system
  • SRS roof fans: Each cabinet is equipped with a roof top fan for cooling of the battery modules during operation
  • Pre-charge resistor: Pre-charge resistor to limit inrush current when connecting to a load with capacitive input

Slave (SRB)

The SRB monitors cell voltage, temperatures and balancing status of the cells via CAN to masters. Each slave is connected via signal heartbeat, which provides a third layer of safety beyond software intervention.  The SRB provides all statistical data on max and min cell capacity state of charge, voltage and temperatures.

These SRB are compliant with EMC and safety industry standards (EN61000-6-2, EN6100-6-4, EN 61010-1 EN50272-1) and UN 38.3.

Master (SRC2)

The Storage Rack Controller (SRC2) is a control unit. The controller communicates and controls the connected battery modules. It provides the power to slave system (SRB). A pre-charge resistor connected in the system provides limited current for initialising the charging process through the inverter. The SRC2 controls the roof fan and monitors its function through the reported back speed signal. Leclanché’s “Slave protocol – CAN” or “Slave protocol – Modbus / TCP” are available to communicate with the host device.

Low voltage BMS

Leclanché develops low voltage BMS solutions for 24/48 volt battery modules. These BMS are single board and master/ slave for multiple applications like Automated Guided Vehicles (AGVs) and 2-3 wheelers. Low current BMS offer shunt and MOSFET on board and come in a highly compact design. High current BMS on the other hand are provided with an optional control panel with contactor control.

All BMS have built-in algorithms for state of charge and state of health, diagnostics tool, GUI, CAN communication ports and accurate sensors for monitoring voltage and temperature.

Boards typically have 100V isolations.

48V modules

2/ 3 wheeler BMS


Leclanché’s Energy Management System (EMS)

The Leclanché’s EMS software suite offers cutting-edge tools to manage large grid-connected Battery Energy Storage Systems (BESS). Leclanché’s EMS is designed to integrate flexibly with multiple battery/inverter combinations. These include mix-and-match configurations with multiple vendors, subsystem software versions, Battery Management Systems (BMS) and various power and energy ratings with a very high level of reliability and performance.

The EMS consists of the following components:

  • Power Plant Controller (PPC) for managing BESS operation
  • Human Machine Interface (HMI) software for interacting locally or remotely with the PPC
  • Cloud-based software for secure remote access
  • Historical data logging and reporting (cloud-based or on-site)

Leclanché’s EMS is recognised in the industry as providing a very wide array of features and benefits which include:

  • Seamless utility back-office integration (including SCADA, DMS, DERMS)
  • ISO frequency regulation ancillary services
  • Energy arbitrage
  • Flexible fleet management
  • Voltage support (Volt/VAR feedback)
  • Power flow stability improvement
  • Intermittency mitigation for wind and solar integration
  • Real-time equipment monitoring
  • Balance of plant integration with HVAC, fire safety and security components

Leclanché provides tailor-made solutions and can custom design EMS based on different combinations of the above features.

Leclanché’s talented and innovative EMS engineers provide end-to-end support from concept to launch and beyond. Thanks to the multiple rounds of rigorous testing in both simulation and real-world environments, Leclanché offers a secure, stable and reliable EMS to manage the toughest challenges on the grid.