Li-Ion Battery Management System (BMS)

Li-Ion cells have many advantages compared with other battery technologies: they are lighter, more durable, can be stored in any state of charge, and they are environmentally benign. However, they require single cell monitor/control in order to ensure safety and longevity.

Our battery management system (BMS) continuously monitors the status of each battery cell and helps keep all the relevant battery parameters, such as temperature, cell voltage and battery current, within their safe limits.

Designed to perform this essential protection and optimise each cell life, our BMS also maximizes the whole battery pack's performance and ensures safety in use. Compatible with most of the commercially available components for electric systems, and designed for maximum flexibility, Li-Ion BMS 14 is the ideal choice for a vast range of applications.

Latest generation of Li-Ion BMS
Latest generation of Li-Ion BMS

    Characteristics
  • Modular (each BMS module can manage up to 14 cells)
  • Small (132mm x 72mm x 19mm)
  • Weight = 68g
  • Microprocessor based (high level of functionality)
  • Low electromagnetic radiation
  • Good EMI behaviour (no need of shielded case)
  • Fits into standard commercially available cases
  • Can be potted in resin and hence fully sealed
  • Designed to allow a wide range of cost effective custom modifications

    Specification list for a BMS module
    (Several modules can be connected via CAN bus to manage any number of cells)

  • 14 cell voltage measurements
  • 7 temperature measurements
  • 2 current measurements (via external shunt resistors or Hall-effect transducers)
  • Calculation of the State of Charge and State of Health
  • Cell equalisation / balancing
  • Two relays with DPDT outputs for protecting the battery from overcharge and undercharge problems
  • Additional hardware protection layer operating the relays
  • Three digital opto-isolated outputs (used to control heating, cooling, auxiliaries, etc.)
  • Three digital opto-isolated inputs used for:
    • Detection of ignition
    • Detection of charger connection
    • Custom functions (e.g. speed measurement)
  • Closed loop charge control
  • Closed loop discharge control
  • Two PWM or digital outputs (usually used to control motor controllers or chargers)
  • External +5V output available
  • Interfaces:
    • CAN bus for communication between BMS modules and external components (e.g. charger, motor controller)
    • RS232 bus for visualising data, setting parameters or data logging
    • RS485/RS422 bus for communicating battery status to other devices (e.g. higher level vehicle controllers). This option is currently available on special request only.

    BMS options
    REAPsystems Ltd. offers different levels of customization:

  • Standard off the shelf BMS
  • Off the shelf BMS modified for specific requirements
  • Custom BMS design optimised for specific application