Another Lithium Post/Question

[CBears]

I know this has been discussed to death and I've been reading posts all morning but have a quick (hopefully) question. I've got a 2024 Cougar 25mle with the 220 solarflex package and I never boondock. The battery that came with my unit is LA deep cycle 45ish AH and needs replaced this year. If I don't keep a trickle charger on it, a couple of cloudy days will drain it pretty low if I leave the in-command powered up. I've got a 100ah lithium battery on the way. I've read all kinds of posts about the WFCO converters fighting with the solarflex for charging however I haven't found a definitive answer to the following:

Even if the WFCO doesn't recognize that it is charging a Lithium battery, won't the solar panel go ahead and finish off the battery charging? If I'm not boondocking will I even notice an issue with this?

 

[NH_Bulldog]

You are correct. Even if the converter doesn't fully charge the battery to its capacity, the solar will or at the very least will try (the output of the solar panel has to overcome the ongoing system drain on the battery, so you might never see 100% charge). The difference is fairly negligible unless you are relying on every bit of juice the battery can put out, but if you are not boondocking, you might never even notice that it isn't fully charging.

Just be sure that you change the solar charge controller settings to lithium and you should be fine.

Before I added a second solar panel and had my converter modified, at best I would only get up to a 96-97% charge on my two 100ah LiFePO4 batteries.

 

[JRTJH]

You will be "just fine" with a 100 A/H lithium battery and your current WFCO converter/charger and solar system. As Rob posted, just be sure to change your SolarFlex charge controller to the lithium charge profile.

Here's the "math facts" about what you will have with your system, IF (note the IF) your WFCO remains in or changes back to the FLA charge profile: The WFCO will charge your Li battery to about 80% with no harm to the battery. If you regularly have shore power available, you should notice no change in 12 VDC availability. In fact, "doing the numbers" if you currently have a 45A/H FLA battery, your Li battery will have approximately 80 A/H available with the WFCO in FLA profile. The FLA battery can be discharged to about 50% without damaging the battery, so a "usable A/H capacity of 22.5A/H. The Li battery can be discharged to about 10% (90% usable availability) so you'll have 90% of your 80A/H available, or around 72A/H available. That's still somewhere around 3 times the "functional capacity" of your current 45A/H capability. And this is with NO INPUT FROM THE SOLARFLEX SYSTEM.... It will add to your capability on sunny days and that will increase your A/H availability to even better performance.

So, even with the "vulnerability" of the WFCO to "not properly trigger to the correct Li charge profile", you still will have around 3 times the available battery power that you currently have. You could change out your converter/charger with some other brand/model and potentially eliminate that problem with full charging capability, but the way you use your trailer, I'd simply ask, "Why spend another $200- 300 on something that will not change the way you use your trailer?

 

[CBears]

You will be "just fine" with a 100 A/H lithium battery and your current WFCO converter/charger and solar system. As Rob posted, just be sure to change your SolarFlex charge controller to the lithium charge profile.

Here's the "math facts" about what you will have with your system, IF (note the IF) your WFCO remains in or changes back to the FLA charge profile: The WFCO will charge your Li battery to about 80% with no harm to the battery. If you regularly have shore power available, you should notice no change in 12 VDC availability. In fact, "doing the numbers" if you currently have a 45A/H FLA battery, your Li battery will have approximately 80 A/H available with the WFCO in FLA profile. The FLA battery can be discharged to about 50% without damaging the battery, so a "usable A/H capacity of 22.5A/H. The Li battery can be discharged to about 10% (90% usable availability) so you'll have 90% of your 80A/H available, or around 72A/H available. That's still somewhere around 3 times the "functional capacity" of your current 45A/H capability. And this is with NO INPUT FROM THE SOLARFLEX SYSTEM.... It will add to your capability on sunny days and that will increase your A/H availability to even better performance.

So, even with the "vulnerability" of the WFCO to "not properly trigger to the correct Li charge profile", you still will have around 3 times the available battery power that you currently have. You could change out your converter/charger with some other brand/model and potentially eliminate that problem with full charging capability, but the way you use your trailer, I'd simply ask, "Why spend another $200- 300 on something that will not change the way you use your trailer?

Thank you for this! This is the way I was thinking but didn't want to get somewhere on vacation and find out I was wrong. I appreciate your time.

 

[CBears]

You are correct. Even if the converter doesn't fully charge the battery to its capacity, the solar will or at the very least will try (the output of the solar panel has to overcome the ongoing system drain on the battery, so you might never see 100% charge). The difference is fairly negligible unless you are relying on every bit of juice the battery can put out, but if you are not boondocking, you might never even notice that it isn't fully charging.

Just be sure that you change the solar charge controller settings to lithium and you should be fine.

Before I added a second solar panel and had my converter modified, at best I would only get up to a 96-97% charge on my two 100ah LiFePO4 batteries.

Thank you for this! I will be changing the solar system to recognize the battery right away. I appreciate your time.

 

[RacerX-KEY]

Just a caution, your mileage may vary….

Before I swapped my converter and after I had swapped to Lithium batteries I saw a slightly different effect than others have mentioned. By itself my WFCO 9855 would only charge the lithium batteries in Bulk and at Absorption voltage one time before it would enter float mode at 13.2 v. The problem is unless I added a large load the lithium batteries would never drop below 13.2 (13.1 approximates 40% SOC). And, to further compound things on the converter side, the trigger from Float back to Bulk mode (rarely seen) or Absorption (13.6) was even lower. I think it waited until the batteries would reach 12.6 volts before leaving float and re-bulking.

So, on a cloudy day where the solar charge controller was not able to contribute, I could leave a full hook up campground or my home base with less than 50% SOC. This, after being plugged in all night or weekend.

I have read many of the forums that estimate that you will get to 70% state of charge, but the only way I could do that with the converter alone was to force it into bulk mode with either a very heavy load or a flip of the switch on and off for the converter (where the switch is the circuit breaker, of course).

As mentioned earlier, if you have full sun and your solar panel is generating energy greater than your usage, it WILL top off the batteries, but IF it is just barely making by and keeping the batteries near 13%, the WFCO converter would never contribute to the load as it views itself in float mode and waits for the voltage to drop down below 12.6 before it will trigger the exit from float mode.

I worked this way for 6-8 monthsand even used an AC smart charger to supplement the charge controller, but eventually broke down and upgraded the WFCO.

 

[RacerX-KEY]

Just a caution, your mileage may vary….

Before I swapped my converter and after I had swapped to Lithium batteries I saw a slightly different effect than others have mentioned. By itself my WFCO 9855 would only charge the lithium batteries in Bulk and at Absorption voltage one time before it would enter float mode at 13.2 v. The problem is unless I added a large load the lithium batteries would never drop below 13.2 (13.1 approximates 40% SOC). And, to further compound things on the converter side, the trigger from Float back to Bulk mode (rarely seen) or Absorption (13.6) was even lower. I think it waited until the batteries would reach 12.6 volts before leaving float and re-bulking.

So, on a cloudy day where the solar charge controller was not able to contribute, I could leave a full hook up campground or my home base with less than 50% SOC. This, after being plugged in all night or weekend.

I have read many of the forums that estimate that you will get to 70% state of charge, but the only way I could do that with the converter alone was to force it into bulk mode with either a very heavy load or a flip of the switch on and off for the converter (where the switch is the circuit breaker, of course).

As mentioned earlier, if you have full sun and your solar panel is generating energy greater than your usage, it WILL top off the batteries, but IF it is just barely making by and keeping the batteries near 13%, the WFCO converter would never contribute to the load as it views itself in float mode and waits for the voltage to drop down below 12.6 before it will trigger the exit from float mode.

I worked this way for 6-8 monthsand even used an AC smart charger to supplement the charge controller, but eventually broke down and upgraded the WFCO.

Just noticed that you have a 2024. Your WFCO might be the auto detect version which should work better.

 

[NH_Bulldog]

Just noticed that you have a 2024. Your WFCO might be the auto detect version which should work better.

No, that is a known issue with the "auto-detect".......it doesn't. (at least not consistently or reliably). I sent my converter back to WFCO and they added an internal jumper to force it to a lithium-only charge profile since I do boondock often. Otherwise the converter would charge the batteries at lead-acid, and the next cycle would do it once on lithium, and then revert back to a lead-acid profile unless you kept the solar disconnected when on shore power and the converter initiated Bulk mode.

Most people might never know or care that their auto detect wasn't actually auto detecting. My converter happens to be in a very accessible location and at a glance I can tell what mode it is in by the LED lights that are showing. When I unplug from shore power and head out on a trip, I want to know that my batteries are fully charged, otherwise it's like starting out a long trip with a 3/4 tank of gas in the truck.

 

[RacerX-KEY]

“When I unplug from shore power and head out on a trip, I want to know that my batteries are fully charged, otherwise it's like starting out a long trip with a 3/4 tank of gas in the truck.”

Yeah that was my frustration, once aware of the problem, I used the 15 amp smart blue charger to ensure I was getting at least some charge when solar was not able to do it by itself. With a 12 V refrigerator, it wasn’t pleasant to leave for a long trip with less than fully charged batteries.

 

[JRTJH]

“When I unplug from shore power and head out on a trip, I want to know that my batteries are fully charged, otherwise it's like starting out a long trip with a 3/4 tank of gas in the truck.”

Yeah that was my frustration, once aware of the problem, I used the 15 amp smart blue charger to ensure I was getting at least some charge when solar was not able to do it by itself. With a 12 V refrigerator, it wasn’t pleasant to leave for a long trip with less than fully charged batteries.

What brand Li battery do you have and do you know how that battery BMS operates? The issue you have could be an "internal Li battery issue" rather than a WFCO issue if the battery's BMS is "tricking the WFCO into believing the battery is fully charged when it isn't ... It's easy to fall into the trap of blaming the "component that's not functioning correctly" when in fact, in a system with three individual systems (solar system, battery BMS and converter/charger) any one of those systems may be interacting to cause your "battery not fully charging" problem. I'm certainly no expert on the "inter-operability" of all the unique possibilities with all the different brands of systems, each with their own "claim to fame", but it may not be the converter that's causing your issue. Not saying it is, just saying it may not be as it appears at first glance or even at second or third glance.

 

[RacerX-KEY]

What brand Li battery do you have and do you know how that battery BMS operates? The issue you have could be an "internal Li battery issue" rather than a WFCO issue if the battery's BMS is "tricking the WFCO into believing the battery is fully charged when it isn't ... It's easy to fall into the trap of blaming the "component that's not functioning correctly" when in fact, in a system with three individual systems (solar system, battery BMS and converter/charger) any one of those systems may be interacting to cause your "battery not fully charging" problem. I'm certainly no expert on the "inter-operability" of all the unique possibilities with all the different brands of systems, each with their own "claim to fame", but it may not be the converter that's causing your issue. Not saying it is, just saying it may not be as it appears at first glance or even at second or third glance.

lol. No trickery. Just basic lithium profile and the charge algorithm used by WFCO. The two just didnt play well together. Unless under load any brand LIfeP04 will stay at a higher voltage than the WFCO call for Re-bulk or absorbtion voltage until drained to below 40% or so. A Quickgoogle Look at any of the the SOC profiles for Lifep04 batteries will show that 40% SOC equates to about 13.1 volts. This was still too high to trigger the WFCO rebulk phase. (WfFCO uses voltage to trigger its charge profile changes which worked well with LA but not so well with the relatively flat Lifep04 curve ). This is what I observed as well as what the math predicts.

 

[JRTJH]

lol. No trickery. Just basic lithium profile and the charge algorithm used by WFCO. The two just didnt play well together. Unless under load any brand LIfeP04 will stay at a higher voltage than the WFCO call for Re-bulk or absorbtion voltage until drained to below 40% or so. A Quickgoogle Look at any of the the SOC profiles for Lifep04 batteries will show that 40% SOC equates to about 13.1 volts. This was still too high to trigger the WFCO rebulk phase. (WfFCO uses voltage to trigger its charge profile changes which worked well with LA but not so well with the relatively flat Lifep04 curve ). This is what I observed as well as what the math predicts.

Has any of that changed with the newer WFCO converter/chargers or with the "software upgrades" such as what NHBulldog obtained from WFCO when he sent his converter/charger back for modification ??? What I'm getting at is that what you see "might be an issue with some of the "as built in past years" chargers and is "no longer the case" with the new ones. The issue then would be "What date/model/part number incorporates the new design that solves the issue you have" ???? I can't believe that WFCO, with all their recent upgrades has somehow "completely ignored that problem while fixing the others" ....

 

[NH_Bulldog]

WFCO has done some Firmware updates that I can only hope are helping to fine tune their product. On the WF-9855-AD I have seen v1.17 on a unit on a sales lot. Mine had v1.19 and after I sent it to WFCO for the modification it came back with v1.21A so they are trying something at least.

Once my warranty is up on the converter, I might just open it up and remove the jumper plug they installed and see if it performs any better than the firmware v1.19 did for me. I can always reinstall it if there was no improvement.

 

[CBears]

GREAT information!!! One more followup question then. Let's say I get to a campsite, for me it will always have electricity. I forget the number of my WFCO but it did have the AD after it so it "should" learn what battery type I have. Let's say I just make it a habit of shutting down the solar array while at the campsite and not turning it back on until I leave the campsite. Wouldn't that do the trick? Shouldn't the convert change to lithium and charge appropriately the whole time I'm plugged in? My battery will have the bluetooth so I should be able to tell where it is charge-wise.

 

[JRTJH]

Yep, what you're proposing, disabling the solar system when camping with full hookups, should work. I'd just question whether it's even necessary given the increased battery capacity and the upgrades from previous models of the WFCO components. A possibility, not yet mentioned, is that you could consider asking WFCO to modify your converter/charger like they did for NHBulldog. If you're unable to work with the "down time needed to send it to them for modification" then as he once mentioned, WFCO was willing to send him the kit so he could modify it himself. It seems like a simple mod that's not technically difficult for the average owner with some electrical skills, but as he also said, if they send the kit and an owner does the install, then that voids the 2 year warranty on the unit.... So, that's another possibiity for you. Once your WFCO AD converter/charger is modified to be "lithium profile only" then all the issues of reverting to FLA profiles and float charges are resolved.

 

[CBears]

Yep, what you're proposing, disabling the solar system when camping with full hookups, should work. I'd just question whether it's even necessary given the increased battery capacity and the upgrades from previous models of the WFCO components. A possibility, not yet mentioned, is that you could consider asking WFCO to modify your converter/charger like they did for NHBulldog. If you're unable to work with the "down time needed to send it to them for modification" then as he once mentioned, WFCO was willing to send him the kit so he could modify it himself. It seems like a simple mod that's not technically difficult for the average owner with some electrical skills, but as he also said, if they send the kit and an owner does the install, then that voids the 2 year warranty on the unit.... So, that's another possibiity for you. Once your WFCO AD converter/charger is modified to be "lithium profile only" then all the issues of reverting to FLA profiles and float charges are resolved.

Yes, I'm thinking about all my options actually. I don't like to send things off to the manufacturer and I'll be at the 2 year mark at the end of this camping season anyway. Rather than modifying the existing one myself I would probably buy one of the other brands mentioned in some of the other posts I've looked at. I was checking out the "Progressive Dynamics Inteli-Power PD9360v" on Amazon today just in case. I've already spent enough though that I'm going to try using what I've got already and I'm a bit nervous about the reply from RacerX-KEY above about being out there for too many cloudy days. Now that I have a 12v fridge I do use some amps on travel days and a lot of my days are 8+ hours since I live 500 miles from pretty much anything fun. :c)

Also, I spend a lot of time right next to the solar cut off switch when setting up in the park and getting ready to leave. If I just put that simple thing on my checklist, viola everything is fine. DW will happy with no additional cost also.

 

[JRTJH]

Yes, I'm thinking about all my options actually. I don't like to send things off to the manufacturer and I'll be at the 2 year mark at the end of this camping season anyway. Rather than modifying the existing one myself I would probably buy one of the other brands mentioned in some of the other posts I've looked at. I was checking out the "Progressive Dynamics Inteli-Power PD9360v" on Amazon today just in case. I've already spent enough though that I'm going to try using what I've got already and I'm a bit nervous about the reply from RacerX-KEY above about being out there for too many cloudy days. Now that I have a 12v fridge I do use some amps on travel days and a lot of my days are 8+ hours since I live 500 miles from pretty much anything fun. :c)

Also, I spend a lot of time right next to the solar cut off switch when setting up in the park and getting ready to leave. If I just put that simple thing on my checklist, viola everything is fine. DW will happy with no additional cost also.

Also keep in mind that your tow vehicle will provide "some charging power" to the trailer while towing, so your refrigerator likely won't completely discharge your battery during a day of towing. You may not achieve any additional level of charge to the battery after towing, but the 4 or 5 amps needed to keep the refrigerator working should be no problem for the tow vehicle to supply while underway.

 

[CBears]

Also keep in mind that your tow vehicle will provide "some charging power" to the trailer while towing, so your refrigerator likely won't completely discharge your battery during a day of towing. You may not achieve any additional level of charge to the battery after towing, but the 4 or 5 amps needed to keep the refrigerator working should be no problem for the tow vehicle to supply while underway.

That makes me feel better also. Thank you again all!

 

[NH_Bulldog]

In order for the batteries to trigger Bulk charging from the converter, they have to be substantially depleted (no more than 40% state of charge or thereabouts). When I was working with Keystone and WFCO to troubleshoot the issue I was having, they both had me bring the SOC down to 25% to test how the converter "read" the batteries. Once the state of charge gets to a certain point, it switches from Bulk to Absorption and then to Float.

Keeping this as simple as possible: A lead-acid battery charges and discharges along a sweeping curve (remember our old flashlights that got dimmer and dimmer before they finally went out)? A lithium battery charges and discharges along a relatively flat plane (so a lithium battery flashlight gives the same brightness right up until it suddenly goes dark, same with lithium battery power tools, they work until they don't). This difference in how the different battery types take a charge is what the auto-detect converter senses. If a battery slowly stops accepting a charge from the converter (gentle downward curve), it knows that it is a lead-acid battery. But if the battery takes the charge on a flat plane and then stops or slows substantially (no curve), then it knows it is lithium. The SolarFlex comes into play because it will slowly ramp down its charging as a battery is charged. This is fine on a lead-acid battery since it too is slowly ramping down. But with a lithium battery, the solar ramping down fools the converter into sensing a slow downward curve and the program thinks it is lead-acid, even when it isn't. Both WFCO and Keystone engineers advised me to shut off my solar any time I was plugged into shore power and that would keep the auto detect converter in lithium mode.....maybe.

Again, and I can't stress this enough; for the vast majority of people this may all be a non-issue, and they can remain either blissfully unaware, or simply don't care, or be armed with the knowledge (to each their own, this is not a one size fits all world and that is okay!). For me personally, I like to have my solar active all the time since we first load our refrigerator and freezer with food in early April and it stays on until we winterize in early November. I like having the peace of mind that if something happens to shore power, that my batteries and solar panels will keep everything running and my food from perishing. It also saves me a step or two by not having to remember to disconnect and/or reconnect the solar every time we move the camper or go on or return from a trip. Just my preference.

 

[CBears]

In order for the batteries to trigger Bulk charging from the converter, they have to be substantially depleted (no more than 40% state of charge or thereabouts). When I was working with Keystone and WFCO to troubleshoot the issue I was having, they both had me bring the SOC down to 25% to test how the converter "read" the batteries. Once the state of charge gets to a certain point, it switches from Bulk to Absorption and then to Float.

Keeping this as simple as possible: A lead-acid battery charges and discharges along a sweeping curve (remember our old flashlights that got dimmer and dimmer before they finally went out)? A lithium battery charges and discharges along a relatively flat plane (so a lithium battery flashlight gives the same brightness right up until it suddenly goes dark, same with lithium battery power tools, they work until they don't). This difference in how the different battery types take a charge is what the auto-detect converter senses. If a battery slowly stops accepting a charge from the converter (gentle downward curve), it knows that it is a lead-acid battery. But if the battery takes the charge on a flat plane and then stops or slows substantially (no curve), then it knows it is lithium. The SolarFlex comes into play because it will slowly ramp down its charging as a battery is charged. This is fine on a lead-acid battery since it too is slowly ramping down. But with a lithium battery, the solar ramping down fools the converter into sensing a slow downward curve and the program thinks it is lead-acid, even when it isn't. Both WFCO and Keystone engineers advised me to shut off my solar any time I was plugged into shore power and that would keep the auto detect converter in lithium mode.....maybe.

Again, and I can't stress this enough; for the vast majority of people this may all be a non-issue, and they can remain either blissfully unaware, or simply don't care, or be armed with the knowledge (to each their own, this is not a one size fits all world and that is okay!). For me personally, I like to have my solar active all the time since we first load our refrigerator and freezer with food in early April and it stays on until we winterize in early November. I like having the peace of mind that if something happens to shore power, that my batteries and solar panels will keep everything running and my food from perishing. It also saves me a step or two by not having to remember to disconnect and/or reconnect the solar every time we move the camper or go on or return from a trip. Just my preference.

I'm going to be watching the levels on the Bluetooth knowing me. And also knowing me if it isn't working properly I'll be purchasing the aforementioned new converter before next year's camping season. I get a short leash from the DW every year to buy stuff. :c)