Forum Discussion

kacol's avatar
kacol
Explorer
Sep 30, 2015

parallel wiring batteries

Once I have cabled my batteries in parallel, does it matter which battery I attach other neg and pos cables (such as generator, inverter, etc.) to.
  • Chuck_thehammer wrote:
    just because everyone does it.. does not make it correct.... my opinion.

    if plus and minus posts are very near each other.. a cheap piece of plastic sheet will prevent mishaps. (Plexiglas or Lexan) Home Depot or Lowes, etc.


    I agree that a bit of plastic is good insurance, Put it over the posts, not between them.

    Battery posts are rigid and the connections you make to them should be rigid as well. The real danger of having them opposite terminals near each other is going to be in accidentally shorting them with a wrench when attaching the cables or dropping something on the battery that shorts them out.
  • just because everyone does it.. does not make it correct.... my opinion.

    if plus and minus posts are very near each other.. a cheap piece of plastic sheet will prevent mishaps. (Plexiglas or Lexan) Home Depot or Lowes, etc.
  • Hi Phil,

    I did not create the drawing--but it does make it ultra clear how to wire in a balanced manner.
  • Don,

    I've never seen 12V batteries built the way you show in your diagram above.

    All 12V batteries I've seen have the positive and negative terminals along the same side of the battery, so that when you line two of them up as in your picture, a negative terminal from one battery winds up being very close (less than 2 inches) to the positive terminal of the other. I don't like this - it kindof seems a bit "dangerous" to me from a possible shorting viewpoint. But one just has to live with it .... or flip the batteries to get two positives next to each other (safer) or get two negatives next to each other (safer). However doing this means playing games with heavy cable loops to make sure that all cable paths are identical for balance.
  • Rolling Condo wrote:
    Yes. Put the positive cable on the post of battery 1 and the negative cable on the negative post of battery 2. This will give you balanced charging and load setup.


    Or vice versa.
  • Yes. Put the positive cable on the post of battery 1 and the negative cable on the negative post of battery 2. This will give you balanced charging and load setup.