My lead acid batteries
have been neglected and uncharged in a med boatyard and I expect are pretty well dead. (Their insurers won't allow mains power unattended charging
.) So I propose to replace with Lithium cells.
I have a single alternator
which I propose to connect directly to a lead acid and then to a Balmar
MC 614 (set for Lithium). From there I intend to feed directly to two 40 amp Daly BMS units.
Each BMS will control 12 cells; that is with each three cells in parallel and with these connected in series making a nominal 12 volt battery
. The cells are rated at 100 amp, 2C (max 3C). Each BMS sensor/balancing wire will connect to each three cell unit making four wires per 'battery'.
Nominally, I would have two 300 amp batteries
, plus the lead acid.
I also have a 24 volt bow-thruster with a probable load of 450 amps. I have switchgear to series two battery
banks so, connecting the Lithiums, it seems I may have a nominal 600amps feeding a 450 amp load, well under 1C and easy on the Lithiums.
Diagrams I see connect both the charging
feed and the load supply through the BMS units. Should I connect the load side directly to the battery terminals, or at least while the Bow-thruster is in use? I don't want to drain the Lithiums inadvertently in normal use.
Is this a sensible setup? Do I need a charge splitter such as a Sterling Pro Split R unit?
I would appreciate the observations of the A team out there!