thoughts on battery replacement and charging

[captran]

Have a Xantrex statpower true charge 40 charger and 4 T105- (2 banks of 2 batteries each).  This year one of the cells in one of the T105s was 11.5.  the rest of all cells 13 (measured with the hydrometer).  this morning the bad cell had nearly sucked the power out of all the other batteries after only a day anchored.  So I came in and bought one battery and replaced the one with the dead cell. seems like the charger is going non stop at 11 to 12 amps on the bank that is the old bank, and the batteries feel very warm. the place that sells the t105 for 40 dollars less than the other place, has only two left until next week.  soooo...should I replace one for now and have one bank of two new batteries while I wait for the other stock to arrive, or should I get both the new ones, and have one new bank, and the other bank one new and one old and replace the remaining old one next week when the new stock comes in  (was hoping to go out for a week),  feeling perplexed

[lazybone]

Wondering how old the battery is.?
and did you try to equalize the bats using your statpower?

[captran]

5 years , maybe 5 1/2.  yes, did try to equalize.  went ahead and bought the two they had, so now three of four brand new, and will pick up the last one next week when it comes in and we're back in port..  charging is going fine, definitely not over charging like it was. 

[KWKloeber]

5 years , maybe 5 1/2.  yes, did try to equalize.  went ahead and bought the two they had, so now three of four brand new, and will pick up the last one next week when it comes in and we're back in port..  charging is going fine, definitely not over charging like it was. 

5.5 - They may be approaching the end, depending on how well they were babied.  Possibly a shorted cell on one.

May be sulfated, and might benefit from a long-term sulfate bustin' (not equalizing) like with a Battery Minder.  I have sometimes brought back "dead" deep-cycle FLAs with the BM and another that I was beta testing 15+ yrs ago for a company developing a similar system -- but it takes a long time.

Ken

[Mick Laver]

Battery age (for Trojans) can be determined by a two character stamp on the negative terminal. The first character is a letter for the month (ie. B=Feb, E=May) and the second char is a number representing year of manufacture (7 for 2007 ... Or 1997 for that matter). I'm sure this is well-known but the comment about not knowing the age of the battery prompted a reply.

[captran]

went ahead and replaced, as it seemed like they were gassing a lot the last year or so.  after reading the article about maximizing battery life on this site, I think I will disconnect the cables and not charge the 9 months we don't use.  very happy with the charging rates and use rates now that we have all new.   used to be over 24 or 48 hours the use draw would be very different between banks.  now, even after 48 hours, they are within one amp hour of each other.