The Battery Chemistry Module (BCM) is a retro fit device designed to be installed on the output of a current limiting multi output battery charger to allow the battery charger to have independent chemistry selection on each output.
If you have different battery styles/chemistry and different voltage scales (12V and/or 24V) all within the DC System, this BCM is the solution to allow one battery charge to charge different battery chemistries at different voltage scales and at their correct charging profile. So the BCM can essentially turn a very simple battery charger into a multi output, multi chemistry advanced battery charger with other inherent advantages.