Shore Power Lithium Charging

CPT Davenport

Senior Member
Dec 18, 2021
Davenport CA
My stock 2022 FWC charger only charges my SOK 206ah lithium to 60% SOC. Attached is a photo of the existing unit. Is there one I can swap out for that can get me to 100% SOC?


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I just pulled the truck out of the garage for solar charging. The Smart solar says it is in absorption mode but the smart shunt says only 60% SOC.

Battery is at 14.40 volts. This should show 100% per my settings on both victron devices. I set the smart shunt to synchronize SOC to 100%. Now everything is good at 14.40v.

New question is:
Why did my SOC magically change to 60% even though in the settings menu the SOC 100% was still set to 14.4?

Does the smart shunt need to be periodically reset?
I have the BMV-712, and I imagine the software is similar to the Smart Shunt. 60% from 100% is a big change. SOME drift over time is normal (temp changes, slight inaccuracies in Peukert calculations, etc). Even a small parasitic load like the Propane Detector (often hard wired in with no fuses, direct to the battery for safety reasons) can create a mismatch.

I do like you did: after a trip I plug in to shore power and have the camper in the sun... After a few days I call it good and SYNCHRONIZE the BMV.
My IOTA with the lithium dongle will charge my battery in just a few hours. I've never needed to reset my Trimetric since installing the lithium battery. At least it seems to be function correctly. Hard to know for sure :)
I seems as though my stock IOTA did indeed charge the battery fully from the shore power. It was my shunt that was reading an inaccurate SOC. Ever since I installed the smart shunt, I have relied on its reading of percentage. Relying on the voltage from my lithium as a reference has been an inconsistent and variable method of "guesstimating" SOC.

Today I have learned to look at both to % and the volts. At least when the volts are above 14.00 I know that I'm close to 100% and the problem lies with in the translation of the smart shunt.

Nice to know that it is normal to have to SYNCHRONIZE every now and again.
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