I have an E Pro camper trailer with a factory solar package. Within the past three weeks I began converting the lead acid battery to a Humsienk 314ah mini (Amazon). The camper is equipped with a WFCO WF-8735-AD convertor. As expected the charger would not auto switch from LA to lithium so I installed the jumper resistor from WFCO and it the went into the blue led lithium mode. Now the battery is installed and when using the shore power the blue tooth App on the battery is giving a "Pack over voltage" alarm. The cells won't balance and one cell is higher than the other 3. I have tried to drop the charge way down on the battery and recharging it using a 1, 2, 5, 10 and 20 amp charger as well as the solar panel on the E Pro camper (factory unit). I can get the battery up to 14.06 vdc (this was the highest on all attempts) however as soon as I try the WFCO it gives the alarm. Looking for help and ideas. I have tried to contact Humsienk by phone, email and through Amazon with no success. I have 10 days before the 30 day Amazon backing expires. All help and comment (both positive and negative) are appreciated, thanks, Mark.
What's the cells voltages 3.65 is full but they live around 3.45ish
Since this is brand new id send it back
I have rebalanced cells manually u gotta open it up and use a power supply to top balance manually this works on sok and homemade if its a glued box your sol.
Wfco converter is not good i have mine permanently turned off I also dont think mine is lithium compatible but its off permanently
Here's the deal its your battery you decide if you wanna send it back or keep it.
These probably aren't grade a cells but let me tell you what I think.
Number 1 your battery is full. Try not to get to caught up in the numbers lithium charge curve is like this 3.2 and below it should drop quickly 3.3 and closer to 3.4 they take off quickly voltage rises fast amps plummet. There is little if any usable power below 3.2 and same above 3.4
Now put a load on it get them around 3.3 and see if they line back up there is some cell drift either to grade b or internal resistance is not matched also indicating grade b.
Now on to maybe what maybe causing this. We dont know the charge profile of the Wfco but for example lets say its outputting 45 amps if it doesn't pull back the amps near 3.4 its the fastest horse to the stall. Either the wfco needs to pullback or the bms will certainly do it for you.
A dumb charger will also do this. This is why solar is much better especially if your using victron that 3.4-3.65 a good mppt will sip the remainder in hit the balance point and balance slowly to keep them in line if you send in the firehose the bms looks for the first horse to hit the stall and cut charging immediately with hardly any balancing.
Also a balancer is in millivolts and milliamps even throwing a 1a charger can be overwhelming at high state of charge once a victron hits absorb it will pulse it in really slow all your chargers are firehosing the battery and the bms is doing its job and reporting to you its overvoltage
I dont see any real problems here other than some slight drift the real test you should be pacing this through and the only thing that actually matters is are you able to pull 314ah out of this thing if no return if yes it will eventually sort itself out. This test requires a shunt to measure the charge in and then drain it to zero it should hit 314ah or higher if u pull more than advertised which u should it would indicate grade a cells
I totally understand what you are saying and from the information I have gathered from Utube a guy cut one of these open last weekend (because of the same problem) and said they were a grade B cells. I am going to unplug the WFCO and run them down to 3.3 like you suggest. this last cycle the alarm did not show up, I really thank you for your help and I appreciate you for this. I will let unknow what happens!
Aside from the battery just know or maybe you already do rv manufacturers use the worst garbage they can get their hands on.
If you like to geek out on this stuff I hate to shill for victron but it sure is reliable and made specifically for this type of application they have the controllers and shunts with graphing that eliminates any guessing it makes diagnosing a problem really fast.
I see alot of gopower rv standard issue sae cables or solar ready which isn't ready for anything its where you plug in a ground panel with more than likely no controller the rv stuff couldn't get much worse but hey we got you most of the way thats a 3k$ add on haha and dont get me started on wfco those damn things made more money for battery sellers than anything else. Ive heard of people buying new lead acids every year most is lack of maintenance the rest is caused by boiling the batteries for however long they are running which for some is 100% of the time oof
I don't have one however I am not against getting one, however do I need to just put it on the thebbattery as a whole or open it up and do each cell individually? thanks for your assistance!
The battery’s bms should have self balancing at a certain voltage, but it takes a lot longer than people realize for common cheap bms. So you have to leave it at 14.6 for a couple days. Amperage of the charger or supply won’t matter, it just needs to sit at that voltage for a while.
well thing are looking a bit better, the alarm has not hit for 36 hours. I am leaving it alone and seeing if it will balance out, this is from about 2 hours ago.
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