What field battery?

[bbagle1]

I have a polycharge 4 that I will be using to charge four 3 cell 3300mah lipo's at the field. I am trying to figure out what type of battery to get to power it. It pulls about 12+ amps max and I would like to be able to charge each battery three times if possible. How big of a battery will I need? Should I go with a sealed lead acid batt or an automotive type? I don't wanna charge off my car batt so that is out of the question.

[Pinecone]

A 3S 3300 takes 36 watt hours or about 3 amp hours to charge (perfect world). So 4 of them take 12 amp hours, and charging three times means 36 amp hours.

You need a deep cycle marine or Odessey battery. For long life, figure on max 50% discharge, so you need a 72 amp hour or larger battery.

[istandalone]

i was wondering the same thing. would one of those optima car batterys work ok? they're not cheap, but if they'll let me charge my lipos a couple times a cycle that's fine.

[Pinecone]

You want one of the deep cycle ones. Yellow top or maybe orange. Not the red top ones.

[bbagle1]

I ended up purchasing a marine deep cycle battery from wal-mart. It is 75 amp hour. Made for trolling and starting. I think it should work out fine for me. Cost 45$

[istandalone]

be sure to let us know how many charges you can get with your polycharge4 (i'm seriously considering getting one of those, 4 at once!!) using that battery.