I got a used pair of Trojan T-1275s (150 AH each , 82lbs) that the previous owners (new and used golf car dealer) claimed were at about 86% as good as new before they put them on the pallet where they sat for 2 1/2 months before I came along.So first I found them to be about 240AH out of rated 300 or 240/300= 80%. I got them home for a few days and did alternating Equalizing (raises voltage to 15.7v) and Reconditioning (pulse with no rise in voltage) sessions using the VEC1093DBD while checking SG meantimes.All that nursing got SG to more like 1.265 instead of 1.255 at "Full" on average. So I figured I was getting them back to more like 90% from as new.Now am using them while camping as part of a four- battery team with two 6s (232AH) as the other pair. Did a 50-90 today on the whole bank (solar has been weak lately) and various check points show from that, the bank is close to 490AH, maybe 500, so that means the T-1275s are now near 270 and the 6s near 230. 270/300= 90%. This goes with that improved SG I got from the nursing I did with Equalize and Recondition.All of which shows:-alternating Equalize and Recondition does do some good, and-used T-1275s if low cost, can be "worth it" if you happen to stumble across some. (otherwise, as new, they cost too much)

Electricity put into the battery does a world of good and some owners rotate batteries by calendar, your gain. Good going BFL13 !!

Thanks, Mex. It is not your usual RVing situation, but some Forum members wanted an update in case they raided a golf course for some used batts.Another point of interest is that the combo of two 12v T-1275s and two 6v GC2-XHDs, have a voltage drop of about 0.7v when hitting them with a 100a draw, compared with the 1.0v drop when using four 6s.PT is always on about 12v vs 6v for voltage drop, so this supports his story. Also it means that where with four 6s I can go to 50% SOC and stay above 11v inverter alarm, now with the 12v/6v combo I can maybe go down to 40% and still run those 100a draws--to be determined!If so, then maybe I could run 40-80s instead of 50-90s in the winter and meet those two- hour Provincial Park gen time limits instead of that 2 3/4 hours it took today. (Although I can also split the bank and charge two with 100a and two with 40a if I don't care about the Trimetric, which can only do one or the other)

Hi BFL13,Better not tell the golf course owners! Great work.

Change to above plan. My faster recharge plan is to do the two 6s and one 12 (approx. 365AH) with the 100a charger and one 12 (approx. 135AH) with the 40, so I don't waste some of the 100 through early tapering by doing two batts each.The 100a is PF corrected, so the Honda 3000 can run the 140a, where without that PF correction, its limit is 130a.I will use the Trimetric on the 100a and the 40a has its own amp read-out to keep track of the recharge. The over-all AH count will be lost on the Tri, so I will have to keep notes to correct the reading shown there afterwards until the next time all batts are at true full and the Tri can be reset to zero.When/if I carry all six batts (two 6s now at home on Float, replaced for now in trailer with the two 12s)I don't have a plan for how to recharge them all. I have a couple more Vector chargers to add but I don't know how many the Honda will tolerate. Best thing would be to get back home before a recharge is needed on all six. :(

Improving a "Used" Battery Can be Done | Good Sam Community

14 Replies

pianotuna
Nomad III
Sep 06, 2013
Hi,

They are golf cart batteries and ought to behave in the same manner--except the plates are some what thinner. In theory that might make them less tolerant of extreme deep cycling.
KendallP
Explorer
Sep 06, 2013
Well thanks, guys. It's nice to BE back. Been buried in home-schlepping... making hay while the sun is shining, etc. etc. Finally have a moment to breathe.

B, I would think that keeping the bank as a whole would still give you better voltage drop than if your 12s were handling that on their own.

And as far as recovery goes, I would still ASSume that it "boils" down to Antimony. I just wondered if those Trojans were built more like GCs in this regard, thus making them more prone to bubble without pounding them with 17V or something.

I suppose there's a possible experiment for that. You could get them pretty topped, then put one of them in parallel with a pair of 6s and one of your Vectors... hit 'em with an equalizing mode and count bubbles... or, at least... observe and note any differences in bubblidge (yes, it's a word... as far as you know. No need to look it up.)
mena661
Explorer
Sep 05, 2013
I'm also curious as to how they'll recover vs your old 27's. Granted they're not new but I would think that you would also have problems going to your new baseline too even with the reduced capacity. It seems to me there's a construction difference between these and regular grp 27's.
BFL13
Explorer II
Sep 05, 2013
Twice. On arrival a month ago, then at home recently as described, next likely will be at home. The rest of this month is solar assisted and gen/charger as required to stay between 50% and whatever the high SOC is. Once home in October, all batts will get done up and tested to see what this season since April has done to them.
mena661
Explorer
Sep 05, 2013
BFL13 wrote:
K, good to see you back!
Indeed!!

BFL, how many times have you recharged those T1275's back to "full"?
BFL13
Explorer II
Sep 04, 2013
K, good to see you back! Not sure how the T-1275s act for that. They got to their existing "full" ok on the 1093. It is the 1093 being able to get them full (so easy!) that is the make or break for me.

In this case with the T-1275s I did not have a target SG to reach that I could not get to with the 1093 like those dratted 27DCs I had. So whatever they got to was ok.

Looking back, it seems the 27s were already on the down-hill slide and their SG was therefore lower at full than when new.(Now I know more about SG vs SOC on hard-used batts.)

Also I was unwilling to believe those 27s were not able to be charged to good as new when not that old. That would have meant my camping routine was not good for them! So maybe I was getting frustrated for nothing--not sure.

If I ignored Peukert, which I could with so many batts, then I should split the bank and put the inverters on the 12s and the rest of the rig on the 6s. But I only have one Trimetric, so I would lose my AH count. Also need two solars (which I had for a while there) You just can't win, boo hoo.
KendallP
Explorer
Sep 04, 2013
BFL13 wrote:
Another point of interest is that the combo of two 12v T-1275s and two 6v GC2-XHDs, have a voltage drop of about 0.7v when hitting them with a 100a draw, compared with the 1.0v drop when using four 6s.

PT is always on about 12v vs 6v for voltage drop, so this supports his story.

Well I'm sure you were aware when you wrote this that it's not just PT's story. It's a basic tenet in battery design having to do with plate thickness and such.

Good work, B! Sounds like a score.

Now I'm curious as to how these T-1275s handle with the full recharge. You moved away from 12s mainly due to all the effort it took to get that SG back to full after a trip with successive 50-90s. Does the word, "tipping..." open any old wounds? :)

Is there anything magical about these Trojans? Or do they act the same as the old JCs or whatever they were, in this regard?
BFL13
Explorer II
Sep 04, 2013
AFAIK, the 48v golf cars have either six-8s or four 12s. Not sure how many use 12s anymore either. (anybody know?) Be hard for an RVer to get any use from 8s unless he went 24v. You would then need a way to split things so you could run a 24v inverter but still run the 12v things in the rig. You can't tap into one of the 12s in your 24 when using 8s.

? -You could run your rig's converter from that inverter to make 12v without much penalty, as we learned from that testing some of us did recently on having a rig with no battery supplied from a remote power base that had an inverter to plug your shore power into.

Something for the truck-bed battery bank to consider?

Golfers with MHs that take a golf car along RVing could just add an inverter to their golf car and plug the MH into that :) Now you have to recharge the golf car.
RoyB
Explorer II
Sep 04, 2013
I always wanted to follow up on some of the golf cart practices where it seems all of the batteries get replaced when one fails. What happens to those other five batteries haha...

No one knows....

Someboby is getting some good used batteries I suspect...

Roy ken
BFL13
Explorer II
Sep 04, 2013
Change to above plan. My faster recharge plan is to do the two 6s and one 12 (approx. 365AH) with the 100a charger and one 12 (approx. 135AH) with the 40, so I don't waste some of the 100 through early tapering by doing two batts each.

The 100a is PF corrected, so the Honda 3000 can run the 140a, where without that PF correction, its limit is 130a.

I will use the Trimetric on the 100a and the 40a has its own amp read-out to keep track of the recharge. The over-all AH count will be lost on the Tri, so I will have to keep notes to correct the reading shown there afterwards until the next time all batts are at true full and the Tri can be reset to zero.

When/if I carry all six batts (two 6s now at home on Float, replaced for now in trailer with the two 12s)I don't have a plan for how to recharge them all. I have a couple more Vector chargers to add but I don't know how many the Honda will tolerate. Best thing would be to get back home before a recharge is needed on all six. :(

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Improving a "Used" Battery Can be Done

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