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This EQ and solar-controller thing for agm's is always a confusion really because the nomenclature controller manufacturers use for it is totally wrong. And it usually gets disabled by the confusion. Sure enough, EQ for agm's is verboten, except for *some* brands. However, EQ is a lead-acid...

One option if you want to stay with lead, but need the fast charge is to go with "Pure Lead". Ie, Odyssey, Optima, and other pure-lead manufacturers. Costs more, but most support .5 to even 1C (2 hour / 1 hour) charges - *provided you are TIGHT with your charger specs on CV *. Their advanced...

As a preventative maintenance measure, every once in awhile - especially if brand new - charge each separately. If you have a multimeter, and can measure more than 0.1V difference between the batts, recharge them separately again as they can get out of balance with each other.

Oh yeah, the Everstart - always reminds me of the classic youtube vid from years back when the guy from Compass Marine was showing people how nasty an unregulated solar panel can be on them when used as a maintainer when *already* in a fully charged condition:

Don't know if it would be profitable - but perhaps convince someone like Victron to sell high-power 10A or higher "single-cell" nominal 3.2v chargers for LFP diy'ers. Maybe with a selectable 3.5 / 3.6 / 3.65v cv. Even cooler would be an adjustable tail-current disconnect. And put them on...

Well, 3.400v is what's known as the "knife edge" for the balance start trigger. This is at the very bottom of the differentiation between the normal flat-line charge, and the upper charge knee. With your setup, I'd definitely change that to at least 3450. Usually 3500 is in the middle of the...

Ack! SAE connectors. First things I chop off and replace with powerpoles. I don't know how many high-resistance, poor-contact, and oem polarity reversed versions caused me so much grief when starting out with the HF stuff and auto-parts solar projects back in the day... good times. :) At a...

I'm with you! Most recovery efforts are a waste of time, or worst of all, scams to hijack the proper recycling stream. Better not to let it get like that in the first place. Grandma told me that when putting aspirins in each cell, that Advil worked better than Bayer. :)

I'm partial to Tecmate/Optimate if you are going to do lead-acid float / maintain - mainly because I feel that they understand float right - that is, they use a 50% duty cycle of floating (30 min on / 30 min off) voltage. Really handy especially in hot temps for those without precise...

One goal at a time! In this case actually finishing a top-charge and balance. -grin- :) It takes TIME for those bms bleeder resistors to do their job on a bank with a large initial balance variance. - this can take many cycles and I noticed you have zero cycles tracked. Once that's achieved...

Something I've noticed - for some reason some BMS makers think that a balance-trigger-voltage of 3.40v is acceptable. It is NOT, as much as urban mythology tries to make it. Along with "always balancing". How to fry those rice-grain resistors. :) So just checking - if your adjustable bms has...

YIKES - be careful with Gel. Very easy to confuse their CV voltage with those of AGM. Doublecheck that you are not running anything higher than 2.35v / cell (14.1v for typical 12v nominal gel). Lower to 2.33v / cell for hotter climes. Anything higher for a true gel smokes them, although the...

The photo is hilarious! That's how we all feel about our batteries. Almost a human-relationship! :)

Question - if those are true gel's, than no more than 2.35v / cell. (14.1v for a nominal 12v gel) In that hot clime, I'd drop it to 2.33v / cell. Takes longer to charge though. Be careful here - some manufacturers label agm's as "gel", and visca-versca. See your battery spec sheet for what...

Exactly. There isn't enough current to do the job adequately, so balance is waaay off. Nerd-hat suggestion: Put the iMax B6 into single-cell or 1S config for LFP. Charge each one individually. Do a little discharge. Then recharge with the 4S config changing cables obviously. The ol'...

I would never charge my 100ah cells with my iMax B6. For one thing, the current is too low. A minimum of 0.05C is needed, and the B6 barely makes it for those cells. Ie, if .05C is not applied, you'll have a hard time driving them past 3.5v. In fact, what you are seeing is normal for too low...

Nice, but whatever you end up doing, be sure you start out on the right foot, whether the batteries are used or new. You'll need a 20-30 Amp charger, that has the typical AGM CV spec (usually 14.4 - 14.7 - see your batt manual), and charge each battery *individually* before placing them into...

Hi Dr.. The first thing that jumped out at me was that your trigger voltage of 3.4v for the start of balancing is too low. 3.45, perhaps 3.5v would be more appropriate. Using 3.4v as the trigger is right at the bottom of the upper charge-knee - which sounds good but isn't. It has been...

The bms values could be different, such as max output current, so you'd want to make sure they are relatively the same. There's also the difference in LVD disconnect voltages which might not be the same etc. So while you technically can, my money would be if you are happy with the Weize, stick...

Generally, a fully charged LFP is left to rest for awhile will be *near* 13.4v I think you are ok, but perhaps looking for problems. The problem may be that you are using such a dinky amount of current, that the Noco might be timeing out (I'd have to check the specs on mine). This is seen by...

Gotta be careful - otherwise lurkers will turn this into urban-legend slapping cells together and charging up! :) Needs qualifiers - "As long as the cells are reasonably close in both IR and capacity, accompanied by good wiring infrastructure, (clean bus bars etc), a reasonable delta of 100mv...

Sounds like those panels are flat on the roof - if they are, be *especially* careful about rooftop extension shadowing - especially in winter - like from a pop-up vent, or any other protrusion throwing it's long shadow across the panels.

That's a conventional (recycled lead) AGM. Make note of the initial inrush current limitation. I can't see it, but I'll bet it is either 0.25 to 0.3C. (25 to 30a) "C" is the rated capacity - 100ah in this case. It is best not to go beyond 10.7v to 11.7v under load - although these two...

GWL has a blog page detailing it a bit. The key here is that you have to reduce your charge rate to NO MORE than 0.1C, so you have to have some way to regulate that. Like disconnecting part of your array, a smaller charger etc. Or just don't do it at all if you can when the temp is below...

I would only add that if you pulled them out of the RV and they are fully-charged, I'd put at least a small amount of discharge on them before storing. Just to make sure they aren't sitting at the top. Doesn't take much, unless one wants to go totally nutso about it with absolute percentages...

Were you able to actually measure what amount of current the 30v/10A power supply was putting out when charging? It could be far less than 10A ! Perhaps you are annoying them more than charging them. TPPL doesn't like the baby-touch. :) Consider that the primary purpose of these is usually...

The issue here is that this thread is about NOT using any sort of balancing bleeders *after* an initial sanity top-balance has been performed on individual cells. This thread is about the old-school way of doing an initial top-balance yourself, and then using an external LVD of your choice...

Note that if you consult some charts, be *SURE* to confirm whether the chart is either a "one-way" or "two-way" (out and back) chart.

We can napkin-calc it, although you didn't specify what type of lead acid (flooded / agm?). There is a little thing called Peukert - the larger the current you draw, the faster the voltage drops. Example - had you chosen to fire up with only a 10ah little agm, it would last mere seconds with...

A few possibilities: The battery that shoots up to 14.5v may either be the healthiest out of the rest, OR, it may be the most sulfated, and shooting up to 14.5v long before the rest, due to reduced capacity from hard sulfation. How much current did you use when you charged each one up...

If you want to do that it is pretty simple. Example is a 12v system .. After you have done an initial sanity-balance at higher CV's like 14.4v, you reset your CV to 13.5 or below for normal cycling. Maybe 13.45v for the CV. By staying under 3.4v / cell, this ensures you'll never reach a full...

I'd do this regardless - but maybe make sure you've got clean busbars / terminals, and light amount of anti-oxidant paste like no-alox, penetrox etc on the flat surfaces.

A Schumacher charger? GULP! Most notably known for their "speedchargers" to revive knackered vehicular lead-acid batteries, they are very aggressive and designed for that. You could be damaging the bms by using it! Desulfation pulses, and going into a high-eq like 15.5v behind your back...

The problem with using an LFP "drop-in" for UPS duty when it originally had a lead-acid charge circuit is that if the absorb OR float charge in the ups is 13.6v or higher, given enough time, it will charge to full capacity. That could take days or weeks, without giving any significant rise in...

I'm assuming the Vmax Tanks brand of AGM batteries, although I see they also support LiFePO4 now. If AGM, then get close, but don't exceed their maximum input current ratings with your new array (when you calculate the parallel capacity). Typically 0.25 to 0.3C. Perhaps more. Use a remote...