AM Solar cannot assist in the design of isolated multiple battery bank house battery systems. Multiple connected batteries are fine.  A separate starter and house battery bank is fine, but multiple house battery banks are a bad idea.  All house battery systems designed by AM Solar must use compatible batteries connected within a reasonable distance from each other.

Issues with the Multi battery bank systems:

  • Battery banks should not be isolated and reconnected repeatedly with the exception of engine batteries using Bi-directional isolators in some cases. This is due to the potential for extremely high current that can flow between parts of the system when reconnecting. This high current can cause damage to your batteries and to your electrical components.

  • Lithium batteries use Battery Management Systems (BMS) which automatically disconnect charging and loads before the battery takes damage. Due to the different designs of BMS systems you do not want to combine 2 different types of Lithium batteries.

  • Lithium and lead-acid batteries have very different resting voltages and charging parameters.  Combining lithium and lead-acid batteries in one house battery bank would either be exceedingly complicated or harmful to the batteries.

  • Correct battery cable size and length are critical aspects of the design of a healthy system. By connecting multiple battery banks with unique capacities, wire lengths, and wire sizes, you can create an imbalance in the system resulting in some batteries being under charged and/or drained at an accelerated rate.

  • Multiple house battery bank systems are more complicated, more expensive and offer little to no additional functionality.  These systems may be appropriate for an aspiring engineer seeking an experiment on wheels, but it isn’t in line with AM Solar’s business model of providing elegant and functional power systems.