Gary, Thanks for your comments. That's WAY more that I am interested in doing. My electrical system is fairly simple. One battery to start, one to operate the windlass and bow thruster and one house bank to do the daily lifting. Its is charged and managed with a Link 2000R. Since my batteries are only a year old, I would estimate they still have 90% of their life. Also, remember that my existing bank is adequate. If I could simply add two more 6V gells to my bank without making a huge project out of it, I might give it a whirl. But I'm not interested in a huge project and I' don't want to cause a problem where one doesn't already exist. Regards, Randy Pickelmann hard aground in Clearwater MORNING STAR www.morningstar.talkspot.com

Randy Pickelmann wrote: > Gary, > Thanks for your comments. > That's WAY more that I am interested in doing. My electrical system > is fairly simple. One battery to start, one to operate the windlass > and bow thruster and one house bank to do the daily lifting. Its is > charged and managed with a Link 2000R. Since my batteries are only a > year old, I would estimate they still have 90% of their life. Also, > remember that my existing bank is adequate. If I could simply add two > more 6V gells to my bank without making a huge project out of it, I > might give it a whirl. But I'm not interested in a huge project and > I' don't want to cause a problem where one doesn't already exist. > Regards, > Randy Pickelmann > hard aground in Clearwater > MORNING STAR > www.morningstar.talkspot.com <http://www.morningstar.talkspot.com> I see the wisdom in your approach Randy. If it ain't broke, don't fix it. If it's workin' fine, don't mess with it. On the other hand I have not noticed anybody complaining of having too much house battery capacity, have you? Consistant with my earlier message, I still think that if you did add some new batteries to a suite of older ones you just might have some of the hassles I suggested. You might not. It's one of the many risks we consider taking all the time and I was talking about how to mitigate that risk. I'm sure you could go from four 6V's in series parallel to six of them in a series parallel bank, but the smart way to do that without having to buy THREE new batteries is to have the two new batteries each in series with an older battery. That way there are two series pairs with one old battery and one pair with two old ones. Just don't put the two new batteries in series together, that's all. The risk of trouble is pretty small, given that your 'old' batteries are only a year old and we're talking gel cells here, not flooded. And we are talking about adding exactly the same make and model of battery here, right? My point is that surprisingly small differences between the parallel branches of a series parallel battery bank can, and on rare occasions do make major trouble. Cheers, Gary