IQ Battery Management System


The IQ System is an advanced Battery Management System (BMS) for any type of lithium-chemistry battery packs. It is comprised of a single battery pack master controller connected to multiple cell management modules. The units function together to protect and control the entire battery pack.


Without the BMS a high-voltage battery pack is at risk of operating outside of specified limits, potentially leading to complete failure of the individual cells. The Tritium BMS eliminates this risk, by reliably monitoring each cell and maintaining operation within the set limits. It can also completely disconnect the battery pack if any voltage or temperature limit is exceeded.


The IQ BMS is a full battery management system, not just a battery monitoring system. During the charge cycle the Tritium BMS is capable of bypassing fully-charged cells – providing a top-of-charge balance for the entire battery pack and overcoming cell differences due to age and manufacturing variations.



PDF documentation for the BMS is available below:


Software for the BMS is available below. This software works with our CAN-Ethernet Bridge:

Please contact us for firmware update images for your BMU hardware version



Please contact us for more information.

Cell Management Unit (CMU)

The Tritium CMU suits any lithium cell chemistry of any form factor, as the threshold voltages are user-configurable and a simple wiring harness is used to connect the node to the cells. Each node can monitor between one and eight cells, and is powered from the network, not the cells themselves, so the BMS itself does not contribute to cell leakage and imbalance.


CMU specifications
Cell options Any lithium chemistry cell
Communications CAN bus (ribbon cable)
Balance current 250mA
Voltage resolution 1mV
Update rate Full pack @ 1Hz
Max system 32 nodes, 256 cells, 1000V
Battery wiring Simple point-point ribbon, 1-8 cells
Fault detection Redundant voltage sense, cross checked A/D reference, comms timeouts
Temp accuracy 2°C
Isolation Rating 1kV DC
Dimensions 135 x 55mm (250mA node)
Mass 35g
Environmental No enclosure — coated PCB

Battery pack Management Unit (BMU)

The BMU is a bridge between the CMUs and the vehicle communication bus. It controls the pre-charge and main contactors of the battery pack as well as collating the telemetry data from the nodes and providing a summary to other components on the vehicle CAN bus.


BMU specifications
Communications CAN bus to both batteries and vehicle
Contactor Drive 3x 12V 3A, with feedback
Precharge Resistive (includes fault detection)
Isolation Rating 1kV DC
Dimensions 195 x 55 x 30mm
Mass 150g
Environmental No enclosure — coated PCB