battery placement and specific gravities.

Options
Ralph Day
Ralph Day Solar Expert Posts: 1,019 ✭✭✭✭
What has been anyone else's experience with spec gravity readings in relation to the battery placement in the string? I've noticed that the cell closest to the positive terminal cable to the inverter has the highest sg reading and the cell last in the entire string (nearest the neg terminal cable to inverter) has the lowest (although not lower than the lowest in the whole set).

THe reason i ask is, do the cells accept more charge (get more charge) when they are closer to the beginning of the electron flow as opposed to the end of the flow? This brings up the question of rotating the batteries in the string over time. Should they be rotated every few years into different positions in the string? Or is this just too much time on my hands on a Saturday type question?

Looking forward to technical responses, or others...like get off your butt and cut the grass or something, don't make your head hurt for no reason!:p

ralph

Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Options
    Re: battery placement and specific gravities.

    personally i didn't rely on spec grav readings as much as i went with the at rest voltage, but when in doubt of specific cells it does well as an indicator. i can't do that now with the vrla type of battery. i did find that the batteries can tend to charge differently and that it is a good idea to alternate them so as to even out the charging that way. eq charges also help to even things out, but the ones that have higher sg ratings get hit with the eq charge harder than the other batteries do too so they are stressing more than the others. this could lead to those batteries failing early if things aren't evened out.
    as to my grass being mowed, i don't have to as it is now too cold for it to grow much.:D btw my head doesn't hurt in giving this a quick thought. if your's hurts take some aspirins and you'll get the bill soon because i don't want you to call me in the morning.:cry::p
  • Ralph Day
    Ralph Day Solar Expert Posts: 1,019 ✭✭✭✭
    Options
    Re: battery placement and specific gravities.

    Thanks Neil

    Alternating battery placement, hmm. 6 units of 455lbs each, hmm. Sounds like a job for...a couple of people.

    ralph