Lithium Battery

[bkassler]

I recently changed from a Lead Acid Battery to a Lithium Battery. It is a Lithium Blue (made by Discover Battery in Canada) 100Ah 12 volt with full blue tooth electronics connectivity. For anyone not familiar with Discover Battery, this Lithium Blue is quite high-end and very expensive. It discharges perfectly and lasts for about 3-4 days of dry camping without having to scrimp on any of our power needs. However, when I turn on my generator to recharge the battery it will only charge at about 12 amps per hour. The WFCO converter/charger is made to charge up to 36 amps per hour. As the battery gets closer to being 100% SOC the charging amperage lowers all the way down to 3 amps per hour. So, it takes a very long time to recharge the battery. The strange part of this story is that if I run the battery all the way down to 0% SOC (state of charge) the converter/charger then recharges the battery starting at 36 amps per hour and decreases down to 24 amps per hour only when the battery get close to 100% SOC. The problem is not my generator because the same holds true when I am plugged into shore power. Any ideas why this might be happening and any ideas how to fix this?
Thanks,
bkassler

[DonBr]

The WFCO does not have a lithium setting. So, since your battery puts out 13.6V until nearly empty, the WFCO sees it as a full wet cell and just applies an absorption charge. When you get low enough, the voltage drops and the WFCO goes into Bulk mode, which holds for several hours regardless of voltage.

I'm probably like a lot of people - I turned my WFCO breaker off permanently, and use a combination of solar, and a Victron 30A charger as needed.

[bkassler]

Thanks for the response. My WFCO WF-8735-AD Converter/Charger manual says that it is a smart charger, meaning that it has the ability to determine whether the battery is lead-acid or lithium. It is then supposed to be able to set the amperage and voltage accordingly. It says further that if the light on the charger is blue (which it is), it senses a lithium battery and acts appropriately. Your response makes a lot of sense. I don't know, of course, if my charger is actually acting the way the manual says it is supposed to act.
bkassler

[DonBr]

I will admit that I assumed (you know what that means) that you had the more common older WFCO. Hovever, there are a lot user posts, including here, that suggest the AD technology barely works, if at all. They haven't said what they do to sense the battery type, so it is hard to tell how it would be possible to know, or how they would modify the profile on the fly as it were. Here is an example (5 Star!) review from Amazon:
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There is no documentation. I had to call to learn that switching from Lead Acid to Lithium charging profile requires discharging the Lithium until the BMS cuts it off. After doing that charging started at 12.5V and 38 Amps measured at the battery. (It looks like 12 or 14 gauge wire about 6 feet long. A heavier wire might work better) After an hour it was 13.5V and 25 Amps. The last 2 hours were at 13.6V and 21 Amps. When charging ended, the battery showed 13.4V which is slightly less than full charge -- but close enough. This suggests the charge profile is for Lithium Ion, and not LiFePo4.

Update - after connecting the second battery, that was only slightly discharged, then plugging in the converter, it only put out 6.8 Amps -- that's what I got when it was in lead acid charge mode.

The converter switches back to lead acid some times, but also back to lithium. I haven't seen a pattern to explain it. (Blue vs green light inside the converter shows which program is being used) It does seem that putting a load on the battery before plugging in the converter will switch it.
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Not perfected yet, I think.

[bkassler]

Thanks so much for the response and detailed information. I will try just what you suggest and see if that works. The important part will be if the 12.5V limit will be consistent and if placing a load on the battery before plugging in the converter will always turn on the AD lithium sensing part of the converter.

[bkassler]

I discharged my battery to 12.5V and then plugged the trailer into shore power. It is now recharging at 35 amps/hour. Success. Some times I won't want to discharge that low before recharging, so it's not perfect, but it works. On my next camping trip I will see if it will works at higher voltages and with leaving on a load.
Thanks for the help.
bkassler

[Bill Johnson]

Originally Posted by bkassler

I discharged my battery to 12.5V and then plugged the trailer into shore power. It is now recharging at 35 amps/hour. Success. Some times I won't want to discharge that low before recharging, so it's not perfect, but it works. On my next camping trip I will see if it will works at higher voltages and with leaving on a load.
Thanks for the help.
bkassler

. If you go to the WFCO site says yours automatically detects a lithium battery, 99 percent don't. Also on my motorhome if I change to lithium I must change my BIM to a lithium BIM. lithium batteries should never be run all the way down, they are just like lead acid the lower they are drained the less times they will cycle, never drain below 20 percent

[Ann-Marie]

When charging a lithium battery from a smart lead acid charger I plug it into a Christmas timer set to go off for 30 minutes once a day. Each time it comes back on the charger will go into the bulk mode and charge the lithium battery before settling back to a maintenance mode that is too low to maintain the lithium battery.

That solution is not so easy to do on the 12 volt side of the charger .

[RogerR]

My change to lithium included 200 watts of solar and turning off my Wifco. Changing the Wifco would include to much money and a huge amount of trying to figure out the rats nest of wires stuffed under the counter and almost inaccessible.

No problems since as the Renogy panels and MPPT have kept the battery above 50% even with camping with snow at night and the furnace running a lot.

The plus is unless I need AC I can camp anywhere without plugging in.

[Forester2]

In a previous post, I relayed my conversation with a WFCO factory guy and he said a solar charge controller could confuse the converter and slow charging. I'm taking the simplest route and buying a charger to go direct from my generator to my battery when solar's not peaking.

[DonBr]

Yep, the separate charger is the best answer, and since you can shorten the run dramatically, along with heavier wire from the charger, you can maximize the charge rate.

[bkassler]

I spoke with a WFCO Support Technician. He told me that there is a software update to the AD (auto-detect) converter/chargers that fixes the system so that it will always begin charging at the 36 volt charge rate for lithium batteries. But, you do have to send the unit to them in Indiana. They pay freight one way. There is no charge for the update if you bought your RV within the one-year warrantee period. The technician (Shaun) told me that the converter/charger looks for a 30amp load for 30 seconds when determining the charging rate for lithium batteries. So, I tried that and sure enough the converter/charger put out 36 amps/hour till my battery fully recharged.

[DonBr]

So, with current 2023 Jaycos coming with AD standard, how on earth would someone know if they had the software update?

[bkassler]

The technician said that all of their converter/chargers that they have made/sold within the last year (he was estimating) have the software update. That's not when the rig was purchased but when WFCO built them. I bought my trailer in February 2022 and mine did not have the software update so I assume Jayco buys these well in advance of installing them. So, the answer is that I do not know but assume that there is a manufacture date on the inverter/charger.

[DonBr]

Elsewhere a potential buyer of a 2023 asked the seller to take a picture of the label to make sure it was AD. It was, but it also showed the manufacture date was December 1, 2021.

[DonBr]

Misspoke, it was December 10, 2021.