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Is it safe to buy 80AMP Prog. Dynamics lithium converter/charger for two SOC Batts limited to 50amp max charging?

Mark H.

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I have two SOK 200Amp 12v Lithium batteries on order. I will connect them to my RV roof solar panels and replace my current RV (12v) converter/charger to a PD-4100L (12v) to provide DC to the van and also charge the lithium batts. I have a choice of 45, 60, or 80 amps charging.

The two batts will be wired in parallel. However each of the batt's internal BMSs (Overkill I think) are rated for limiting to 50AMP charging.

Is it safe to use the 80 amp converter/charger for recharging? Will the BMS's shut down if more than 50amps or will it simply limit the charge to 50amps. If not, would it be okay to use the 60amp for recharging? (the 60 amp is a two stage charge).

Thanks...hopefully I can get this figured out before the SOKs are shipped out at month end.
 
Get the 2 stage charge.

80 would seem fine to run right at the max but you are really pushing it. If the charge gets out of balance due to wiring or a connection it could trip out one battery, then both. Do you really need full max power? If plugged to utility power I assume you have lots of time to go slower. If running a generator I understand you may want to minimize run time. The older 2000 Honda will struggle at 80 amps, the newer 2200 might do OK.

I would go with the 60 unless you are possibly concerned about needing to charge one at a time then you are looking at the 45.

No the BMS will not throttle the current. If the BMS senses over current it will shut down.
 
Hmmm...80amps may be an overcurrent...although I am unclear how two BMS's (each limited to 50A) in parallel will read respond. I am now leaning to the 2 stage 60a unit.
 
Hmmm...80amps may be an overcurrent...although I am unclear how two BMS's (each limited to 50A) in parallel will read respond. I am now leaning to the 2 stage 60a unit.
If one battery goes offline you will still be out of spec high by 10 amps for the remaining battery.
 
If one battery goes offline you will still be out of spec high by 10 amps for the remaining battery.

I really don't know if the number of batteries matters. If there are two BMS's, one for each battery, I don't know if that means one can use a 100amp charge or if one is still limited to 50A.

I don't think one of the batts would go offline UNLESS the 60A charge triggers one or both batts 50A BMS limits.
 
I really don't know if the number of batteries matters.
It does matter.

If there are two BMS's, one for each battery, I don't know if that means one can use a 100amp charge or if one is still limited to 50A.
Batteries in parallel share the charge.
So if one is rated for 50 amps charge then 2 are rated for 100 amps charge rate.

I don't think one of the batts would go offline UNLESS the 60A charge triggers one or both batts 50A BMS limits.
Batteries can go offline for a number of reasons.
Off the top of my here are some of the ones that would affect charging.
Hi cell disconnect.
Hi pack disconnect.
Over-curent disconnect.
Over temperature.
Under temperature.
Tripped discrete Over current protection device.
Administrative disconnect.
 
Hmmmm...didn't know that two bms with batts would allow the total amps of 100A.
 
I really don't know if the number of batteries matters. If there are two BMS's, one for each battery, I don't know if that means one can use a 100amp charge or if one is still limited to 50A.

I don't think one of the batts would go offline UNLESS the 60A charge triggers one or both batts 50A BMS limits.
Or high/low voltage disconnect
 
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