batterie bank

malcuk
malcuk Registered Users Posts: 1
hi ive a motor home and wanting to put battery  bank in  i have my 110ah in the middle of my floor underside with hatch i want to add two more 110ah but i can only put them in my garage bit as no room to put them next to each other so the other two would be about three feet away  can this be done or not with the right cable or will i lose power any help please

Comments

  • Photowhit
    Photowhit Solar Expert Posts: 6,006 ✭✭✭✭✭
    If we are talking about paralleling 3 - 12 volt batteries, it can be done so they all share equally, but it's a little odd, you would want all the batteries to have the same length and gauge wires going to a common buss bar/connecting point/terminal. This should allow each battery to contribute equally, but might mean you have 3 feet of wire just hanging creating some resistance...lol
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    How old is the existing battery?

    Putting new batteries in parallel with an old one can be a problem as they may have different effective capacities and charging needs. Also, if temperature in the garage is materially different than the floor compartment the charging needs will be different.

    Unless the existing battery is really new and in good condition I'd think about putting a new bank in the garage sized appropriately for your needs. Depending on space, 4 golf cart deep cycle 6v batteries in series/parallel for ~450ah or 2 L16 6v in series for ~350ah might work. AGM (VRLA) are more expensive than flooded, but have advantages in this application.

    If the battery is newer and you add to as planned you would ideally want to parallel with identical batteries wired as Photowhit explained, using good sized cable and being very careful to make good connections.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter