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KendallP's avatar
KendallP
Explorer
Mar 01, 2022

MEXICOWANDERER On Top Charging New Flooded Batteries

EDIT: It appears that things are even worse than expected. MEX was busy, so I found the answer my dang self.

Simply put... you can buy a brand new battery from a reputable company, with a brand new date code... that may be charged only 85% of capacity... which then may have hardened sulfate that may never come off without knowledge and effort.

Using a highly respected, Vector/Black & Decker 1093DBD charger, upon return home from the store, I topped a brand new pair of Duracell GC2s and then hit them with an equalizing charge at 15.9v until completion.

This got the jars to a specific gravity of 1.275 at 60F.

It took me something like a dozen+ more auto-equalization sessions plus one hard, 3 hour session with an 18A manual charger before the specific gravity settled in at 1.300 at 57F. From there we can extrapolate a temperature adjusted SG of about 1.291 at 80F.

So I have confirmed MEX’s information. At least when it comes to this “big” sample of 2 batteries. Read on…


Original Post:

At the bottom of this post, in bold, is a quote from MEX on the subject. If you're not already familiar with the protocol, I do suggest reading it. He has a strong opinion about it... (which is "way" out of character for ol' MEX. :) )

I'm going to see if I can get him to clarify a little bit on just how hard they should be "top charged."

MEX,

The batteries - 2-Duracell (Deka) GC15 6V, 230 Ah, 64 lb Golf Cars

Upon returning home with the new batteries, I auto-charged them with my temp-compensating, 40A Vector / Black & Decker on the 40A setting. At 40F ambient, it took about 5 minutes to go from Bulk to Absorption at 14.9v. I didn't keep track, but it took maybe 6 hours or so to complete the charge at that voltage.

I then used the relatively mild, temp-compensated, auto-equalize setting with a built-in 4 Amp max. After several hours, the current began to taper at a voltage of 15.9 until current tapered to zero and completion.

Results - SG of 1.275 @ 60F in all but one cell which was 1.285. (stored in the garage a few days on float, which brought them to that temperature before testing.) Just seemed a little on the low end to me for 6v, "high acid" batteries. I get higher numbers from my hybrid 27s.

Note: Following the auto-equalization, my little $10 HF Float Charger, with but a 500mA / 15v transformer and a peak voltage of something like 14.08 was able to get the 2 batteries to 14.00 within a day. They were bubbling a little bit, which surprised me, to some bit of chagrin. Not sure I should leave that float charger on 'em 24/7 through perpetuity... especially indoors in the garage.

So am I done? Is that considered a "Top Charge?"

Or should I hit them with the "The Beast" for awhile and resample the electrolyte? ("The Beast" being the heavy Harbor Freight unit that you and I have... which I run switched to the "Start" setting for hard equalizing at 10A... which was shown to be closer to 20 upon testing)


MEXICOWANDERER on Top Charging New Batteries

"Call a golf course if not closed and ask the PRO where they buy their batteries. Freshness matters.

Upon bringing them home give them a TOP CHARGE then let them sit overnight before cycling them. TOP CHARGING adds significant improvement to overall battery life. Not hype or myth. This is a proven discipline.

To save money battery manufacturers are forced to squeeze post greening activation charging to an absolute minimum. If top charge is used prior to first use it conditions the plates. Commercial rate electricity every cent saved is crucial.

Let the batteries rest 24 hours after top charging. This is vital to saturate the positive plates.

Batteries are chemical devices that exhibit curious electrical properties"

.

70 Replies

  • pianotuna wrote:
    shelbyfv wrote:
    I must be missing something. Why start a thread repeating what another member has apparently posted in another thread?:?


    I believe KendallP is hoping that further research and/or real life observations would be available to "tweek" top charging and focus on other aspects battery care.

    PT is right.

    I was hoping to squeeze a little more from MEXICOWANDERER. However... I seem to be working toward answering my own question. I'm currently on my 3rd auto equalizing of the day. I'll check SG again tomorrow.

    That said... another aim of mine was to bring to the forefront a concept once raised by one of our... uber-helpful board members... which was buried within a reply in some random thread. The idea being to help people. There's not much more to miss than that.
    .
  • shelbyfv wrote:
    I must be missing something. Why start a thread repeating what another member has apparently posted in another thread?:?


    I believe KendallP is hoping that further research and/or real life observations would be available to "tweek" top charging and focus on other aspects battery care.
  • 3 tons wrote:
    I just read this - and had to LMAO at PT’s claim (who does not own one), “LFP’s are fussy” crusade… I’m still reeling!!

    3 tons


    I do own an li battery--just not as a "house" battery. You have seen what more than one seller recommends but others may not have. So here is the link--and I warn it is a long read.

    https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/

    Further, I do believe that LI are a viable choice--except when there is cold weather--but they are still "fussy". By that I mean for maximum cycle life, don't charge too full, don't take them down to totally discharged, don't float charge them, don't let them get to hot, and don't charge them when it is too cold.

    Here is a quote from the article "Keep the battery temperature under 45 C (113 f) (under 30C if possible (86 f)) – This is by far the most important!"

    Further, Rolls Surrette recommends a charge rate of 0.2 c and a maximum charge rate of 0.5 c for LiFePo4 jars.
  • I must be missing something. Why start a thread repeating what another member has apparently posted in another thread?:?
  • 3_tons's avatar
    3_tons
    Explorer III
    I just read this - and had to LMAO at PT’s claim (who does not own one), “LFP’s are fussy” crusade… I’m still reeling!!

    3 tons
  • IMO use your 27s for the emerg home job instead of the two 6s, and get two more 6s. Use 4 sixes in the MH until next time, then see where the RV battery market is at.
  • OK, I ran another auto E with the B&D. Took maybe 3 hours or so, which told me it maybe doing some good.

    Let them rest for a day and took a reading from one cell.

    1.285 at 50F. Which is roughly the equivalent of 1.280 at 60F.

    So that would indicate a gain of about 0.005

    Then I ran a couple more and got 1.300 this morning at 33F. That would be roughly a 1.290 equivalent at 60F and a 1.280 at the 80F standard.

    So it seems I'm making progress.

    The Beast would probably get this done quicker. But at a slight risk of eating some of the plates. With the BD... I can just keep running auto Es until there is no increase.

    But MAN was MEX right! (surprise)

    The date code on these is the same month I bought them. 2/22. What percentage of average GC2 buyer is going to even KNOW they need to do this kind of procedure before installing their brand stinkin' new batteries... let alone have the equipment to make it happen. I'm betting it's less than 1%.

    Makes me wonder...

    In my research of LiFePo4 info, I came across a youtube video with some extensive testing between the LFPs, AGMs and 4 Costco / Interstate GC2s. He noted the lead/acid batteries did not perform to spec... even under mild conditions like an 8A draw per 4 GC2s at room temperature. Stopping at 12.0v, they came in at 197A (47%.) At first that had me concerned. But I'll bet you anything the guy didn't fully top them after purchase.

    I mean, I've made about a 0.015 gain so far. That's fairly significant.

    But the GC2s fared much worse discharging at 80A. And much worse in the cold.

    So I'm leaning toward not putting good money after bad. Maybe start by leaving the G27s in the tray and adding some LFPs under the bed to build capacity. But that's for another thread.
  • BFL13 wrote:
    IMO they need a second dose of E with the B&D 40 to get them to full SG. Mine get to near 1.3 at mid fluid level. A tad less filled.

    Does this mean two 6s?

    Yeah, the levels are right about where they should be to be considered "full"... which is just under the level markers by maybe 1/8".

    That's a good idea... running another shot with the B&D.

    And yes. 2. Not for the motorhome. For an emergency home solar system to supplement (hopefully not eventually needed to supplant) my generator... using my pair of 120W portable panels.

    My pop gave me his old 12kW continuous inverter, so I could feasibly (but barely) keep one of my fridges cold if necessary. Otherwise, certainly some LED lighting and NiMH battery chargers.

    I may have neglected to mention these in my other thread.
  • IMO they need a second dose of E with the B&D 40 to get them to full SG. Mine get to near 1.3 at mid fluid level. A tad less filled.

    Does this mean two 6s?
  • Trojan also mentions that full AH capacity isn't reached untill XX charge discharge cycles. Don't recall what XX was, but I think it is in the range of 25-50. And I don't know if they mentioned how deep to discharge them. On the trojans I've had I've intentionally discharged them to below 50% for at least the first dozen or so cycles and mixed in a few down to 30%ish. With good care I typically get 10+ years with plenty of deep (near 75%DOD) discharges.

    Hopefully Mex can chime in on the "break in" period.

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