Converter with adjustable charge current?

[rickst29]

When I pre-tested three components on the living room floor, I didn't suffer a BMS 'over-current shutoff' while charging the "small" battery at about 60A. IIRC, I had not yet customized the BMS maximum charge current to allow for that value. The default max-charging value within that BMS was 50A.

But it certainly depends on a couple of factors. How finicky and accurate is your particular BMS? And, do you have any other loads consuming power?

IIRC, I had the Inverter turned on at the same time. It was not running any active loads at the same time, but any power it consumed while "idle" was not going through the BMS to reach the battery cells. This may have been around 50-80 watts (5-6A).

My Daly "Smart" BMS units are inexpensive, and they are known to have issues with current measurement. BattleBorn BMS may be more accurate and more finicky, I've never stressed one of the BattleBorn batteries which I have installed (within RVs of other people).
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Unless you make it a special point to activate "Boost" via the pendant, shortly before one of the batteries is about to enter "balancing mode", the Voltage of the WildKat will have fallen to 13.6V "float mode". Although I have seen my batteries accept high current at 13.3 Volts (on the terminals) with 14.4V charging Voltage applied via the pendant, I haven't seen them pulling a ton of current when approaching "balance voltage" with 13.6V supplied:

When one battery goes into "balancing mode", my other is typically accepting only about 15-22 Amps. I haven't abused them forcing "Boost Mode" when the battery Voltages begin to rise above 13.3V.

Photo for reference, show WildKat with Inverter (and an irrelevant MPPT controller), with the old LFP battery (whose cells I stole, in order to create the newer "small" battery with cell compression and the better BMS). I used roughly the same configuration, but forgot to take another picture, following the construction of the "small" battery.

[rickst29]

I think that Randy posted the wrong photo on his website. My 'WildKat' has a different board layout within the right side portion: my bigger capacitors are oriented differently, my 120v inductors are moved to the short side (far right), and I don't have a giant tower with wire terminals at the rear right.

[Wavery]

ShrimpBurrito.... check your PMs

[jagizzi]

I recently purchased a PD4645VL converter/charger from Bestconverter.com and the pin optioning for charging profiles is a little different from what is shown in this thread. Note that this is the direct replacement option for my original Parallax unit and it did just screw right into the existing box.

I have also reached out to Progressive Dynamics for additional info on the differences between AGM charging and LI charging but have not yet had an answer.

I am very interested in what is finally determined here as I am also changing out to LFP batteries, SOK 206ah but have not yet figured out the best charging method. I will start with AGM based on discussions I've had with Rick but I would still like to know the details around this charging scheme.

[jagizzi]

The charger is currently set up for FLA's. To go to AGM's I would just need to place a jumper on the two pins marked for Gel. LI would require the other jumper move to the LI pin, not exactly sure what the WIZ setting does for the AGM profile.

[rickst29]

(1) The Charge Wizard pendant is still useful within AGM/GEL mode, to force higher voltage when charging from a generator (with noise and gas consumption, you want to minimize the time spent charging).

(2) When run in AGM/GEL mode, PD controllers (including my WildKat variation) fall from "float mode" of about 13.6 Volts, down to a "storage mode" charge voltage of only about 13.1 Volts. This is great for lead-acid batteries of all types, but not entirely optimal for Lithium, because the Voltage (just 3.275 per cell) is insufficient to invoke "balance mode" on the Battery Management System.

I don't have access to my charge wizard pendant during winter storage, so the charging voltage has fallen to 13.1 volts. However, my battery cells reached "balance mode" Voltage while the PD was still charging at 13.6 Volts, and the cells have remained in balance as they have slowly fallen towards about 3.25 per cell.

I wouldn't recommend using the LI jumper setting on a PD controller. That "blasts" the battery string with 14.6 Volts at all times the Trailer is connected to shore power, stressing the BMS.