REC Battery Management System

To maximise LiFePO4 battery lifespan the cells in the battery must be kept within the voltage window as recommended by the manufacturer.    This requires a Battery Management System (BMS) that monitors the cell voltages and:

  • can balance the state of charge of the cells 
  • is able to inhibit charging to prevent cell overvoltage
  • is able to inhibit discharging to prevent cell undervoltage
  • is able to activate the above charge and discharge mechanisms in event of over/under temperature or other system issues
  • is configured (wired) to support long-term storage of the battery system with leakage currents in the micro-amperage range.
  • record occurrences of cell voltage exceeding low/high voltage limits  (note that our systems are designed to prevent this ever occurring)

4-Cell Active BMS

The REC Active BMS for 4 cells (nominal 12V battery) is a high end unit which, in conjunction with Solar4RVs designed opto-isolated adaptors and wiring guidelines provides all the necessary functionality to meet the LiFePO4 cell manufacturer's requirements for the BMS.  

16-Cell BMS

The 16-cell unit accommodates from 5 to 16 cells and has proven "plug-and-play" compatibility with SMA Sunny Island inverters (over 200 units are in operation with SMA inverters).


Bi-stable relay drivers (high/low side), pre-charge resistors, relays are available.

Support:   We support the REC BMS units across Australiia.   For example the REC BMS units are used on the Diesel-Electric hybrid Greenline boats for which we provide support.  

We work closely with the manufacturer and can provide rapid responses to requests for support and firmware upgrades.   

Full Kit: REC Active Balancing BMS for 4 cells

Electronic Unit + wiring harness


REC Sunny Island (SI) BMS + Temp sensor + Shunt Cable + CANBus Cable

For SMA Sunny Island, Studer Innotec Victron inverters


REC BMS Slave BMS for 16-cells for 9M Master unit (special order)

For lithium battery packs with up to 195 cells in series


REC BMS MASTER UNIT 9M (special order)

Master + slaves with up to 240 cells in series


REC BMS LCD Touch Display

Suitable for 7R BMS, Q 16S BMS, Active BMS


REC Bluetooth Low Energy (BLE) module

Connects REC BMS to your Android / Apple smart device


REC Pre-charge Resistor and Relay 11-68V 2-11 Seconds 66R

Controlled inrush current flow for capacitive loads


REC Cable DB9 to RJ45 for CAN-Bus

for CAN-Bus to Sunny Island inverters


Relay Contactor SPST 500A 48VDC (32-95VDC) EV200ADANA with economiser

Use for battery isolation/disconnect switch


BMS Current Sensor Shunt 200A 50mV

Suitable for 7R BMS, Q 16S BMS, Active BMS


BMS Current Sensor Shunt 300A 50mV

Suitable for 7R BMS, Q 16S BMS, Active BMS


BMS Current Sensor Shunt 500A 50mV

Suitable for 7R BMS, Q 16S BMS, Active BMS