Thinking about going Lithium...

[psy1]

Originally Posted by kscherzi

I heard it said repeatedly the power cable through the trucks seven pin connector is so lossy between truck alternator to trailer battery that its not considered a significant source of battery recharge power.

Can anyone quantity this? For example if one had a fully discharged 100 amp battery, and drove for one hour, how many amps (typical) would go into the battery?

You are correct. The 7 pin harness will not charge adequately. You need a separate system, meaning a very thick cable coming off your alternator to an Anderson connector adjacent to the 7-pin, then an Anderson connector on the trailer that feeds the DC-DC charger.

The 7-pin connection is more like a trickle charger.

Check out the Adventurous Way youtube video on installing a DC-DC charger. They used a Renogy. I will be using two Victron 30 amp DCDC chargers in parallel. The advantage of DCDC chargers is that you can bulk charge the lithium battery array quickly, e.g. at 60 amps per hour of driving. With a 200 amp/hr battery bank, you could be fully charged from almost dead in 3 hrs of driving. Of course, solar roof panels would be additive to the charge up to the max capacity of the charger.

[Bigventure]

Originally Posted by Jerrylax

We have a 2017 30 classic...what did you do (if you did it) to up grade to lithium? How is it doing for you?

1 Remove battery’s
2 remove tray
3 cut the tray edges off and put the plastic back in
4 put the battery’s in. Don’t mix sizes or brands
5 I put them in E & W because 170AH are bigger than the 100AH.
6 it requires new cables because the bolt are not a common terminal size. I purchase some used cables at the local battery store.
I was adding a Victron BM. So it require a little extra wiring. That’s what the positive bus bar is. The grounds all return via one cable.

If you look under the A frame you can see the wiring going in to the busses behind the sofa. And going to the inverter.

[B. Cole]

Originally Posted by Bill M.

"For example if one had a fully discharged 100 amp battery, and drove for one hour, how many amps (typical) would go into the battery?"

My truck adds no significant charge to a half discharged battery in 7 hours driving. I does not add even 0.1 volts to the voltage I started at.

That amount that TV's charge a trailer battery must vary some with the specific vehicle since others report better charging.

The problem is somewhat in the wiring but mostly in the fact that the alternator sees the fully charged starting batteries and reduces the voltage to keep from over charging them.

If you install one of the units like Dan posted above in your trailer then it will charge as you drive. I am definitely going to add one of those or a larger one this spring. Whether or not I do the lithium conversion.

Using Battleborn's, which I would be inclined towards, it looks like a competent do it your self lithium conversion is going to run around $3000. Two new lead acids and a DC to DC converter will run around $400. I already have a good converter for lead acid installed. I have a couple of months out of town before I could get to it to decide.

Call me a old school wrench spinner, but the day I would pay $1,000 for a battery that I had to put a heating pad on and take its temp every couple hours, would be the day I would expect to be put in the funny farm.😃

[pteck]

Sounds like the OP needs to address his charging issue through the 7-pin first before anything else.

There's lots of things to do to improve the power situation, before going lithium. Solar being one of the primary things as it can solve a lot of usage and capacity concerns without changing anything within the battery system. Also want to make sure existing batteries are healthy however.

Rather than a wholesale lithium upgrade. I would recommend a simple addition of a secondary lithium battery bank as a way to power accessories and 120V devices. Something like a Goal Zero 1000 battery pack tied into the trailer 12V system with a 10amp car charger. Anytime the trailer is charging via 7-pin umbilical or converter, the second bank will also charge.

https://www.airforums.com/forums/f37...um-196422.html

[Justinfinity]

I've posted on this topic several times.

1. There is no problem using specific Lithium battery brands, such as LiFeBlue, and possibly Battleborn, and perhaps others, in cold weather, provided the BMS (Battery Management System) manages the charge cycle according to the temperature. LiFeBlue batteries, which I chose for my installation, have a very good BMS, are designed for cold temperatures, and are available with optional heating pads (which I have).

2. I consider the fire risk almost non-existent nowadays and I installed my LiFeBlue batteries in the front compartment of the Airstream. The old battery box on the A-frame is now a storage box.

3. Don't attempt to charge via the 7-way connector. It might be good for 10A, if that. Why bother?

4. Putting aside wind and hydro, you have three potential charge sources: (a) Shore AC; (b) Solar DC, and (c) Alternator DC. I use all three.

5. If you charge from Alternator, make sure your tow vehicle alternator(s) can handle the load, run an appropriately sized dedicated cable from your engine bay in your tow vehicle to a heavy duty connector between your TV and your trailer. I did this.

6. Depending on your alternator and the type of batteries you choose, you may indeed need to "manage down" the charge current and "manage up" the voltage. In this case a DC-DC charger can help. I did not have to do this because I have dual alternators in my diesel F250 and my LiFeBlue batteries in my trailer have an intelligent BMS that can manage the charge. I used a Victron Cyrix Li-Ct. I added a momentary switch that allows current to flow from trailer to tow vehicle if I needed to emergency start the tow vehicle. If you add a bypass switch, you can do some even more interesting things such as adding another solar charger or providing a source of 12V power from the trailer to other gadgets (maybe a tire inflator, just an example).

7. For shore power, I disconnected the Progressive Dynamics converter, and removed the 1000W inverter that came with the trailer. I installed a Victron MultiPlus 3000/12 inverter/charger where the old inverter used to sit in the front starboard corner of the trailer. There was a 120V AC supply that the old inverter used when connected to shore power, which I repurposed as an extra 120V outlet inside my front compartment. That was nice little bonus.

8. For solar, I installed 6x100W panels on the roof of the trailer and they connect via breaker to a Victron Smart Solar MPPT. On some sunny days in Florida, the panels have exceeded their output rating and I've seen >600W several times. Surprisingly, I've even had good solar output in Canada in the winter.

9. I also have a Victron BMV-712 shunt that allows me to monitor everything via bluetooth on the Victron app on my phone. I can even do this while driving and see when the batteries are full. They are pretty much always at 100% charged well before I reach my next destination.

[Prettygood]

Originally Posted by drbrick

Hello PrettyGood,



I notice your Battleborn instal and have a small suggestion - the batteries are not strapped down. I notice you have fixed them so they don't slide around however, if you should hit a bump or something they will possible jump the rails - I would strongly suggest you add a strap to ensure they don't move - just saying..

Brick, I do appreciate that call out. I installed an L bracket just above the battery level that keeps it in place vertically. Definitely don’t want it bouncing out of place. Since the install is newish, and I don’t have a ton of miles with it, I’ll check it after next week’s trip to ensure it stayed solid. Thanks again

[GettinAway]

Originally Posted by B. Cole

Call me a old school wrench spinner, but the day I would pay $1,000 for a battery that I had to put a heating pad on and take its temp every couple hours, would be the day I would expect to be put in the funny farm.😃

Ok, you are an old school wrench spinner.
You’re also missing out on lighter batteries, that provide twice the usable power, recharge in a lot less time, maintain a higher output of usable power, last a lot longer, can be bought for a lot less than $1,000, and don’t need to be heated. In all fairness, I used to think the same way.

[gypsydad]

Originally Posted by GettinAway

Ok, you are an old school wrench spinner.
You’re also missing out on lighter batteries, that provide twice the usable power, recharge in a lot less time, maintain a higher output of usable power, last a lot longer, can be bought for a lot less than $1,000, and don’t need to be heated. In all fairness, I used to think the same way.

May have missed this, but which batteries are you using, how much were they, and where did you install them (inside or batterybox?) Also, what else did you need to install to use them? (cost?) Appreciate the input.

[Dennis C]

This has been an interesting thread to follow, as I’m also considering some upgrades. I’ve currently got two AGM batteries and a Zamp solar system on my rooftop, with two 90W panels. My Zamp controller has the ability to charge lithium batteries if desired.

I’m considering adding two more 90W panels this spring, which would give me 360W on the roof. I’m also considering buying a Honda 2200 generator with a propane conversion. I’ll likely add an Easy Start to my air conditioner, although we usually camp in the mountains so this isn’t a top priority.

We camp more often without electrical hookups than with them. So far, the solar system plus AGM batteries has worked reasonably well, but at the end of a 4 night trip when parked in the shade, I find that I need a charge, thus the desire to buy a generator. I’m hoping that the two additional solar panels will help here as well.

I may try this setup in 2021, and then move to lithium batteries in 2022. Lithium sounds fantastic, but it seems like a deep rabbit hole once you dive in....

[uncle_bob]

Originally Posted by Bigventure

......

As far as converter upgrades. Who care that the batteries don’t charge 100%. How much difference dose it make? My batteries get charged to 97%. Does 3% less really matter? I had read that keeping lithium’s at 100% charge is bad for them too.

.........

Hi

If *nothing* takes the batteries up to ~ 14.6V at fairly high current, you have a problem. The BMS only cuts in the bank balancing stuff when the input is at the high voltage limit. Lithium's very much *do* need to be balanced. Not doing so is way more significant ( = they fail ...) than a capacity decrease.

Capacity wise, if I charged my lithium's with the stock charger, the capacity would be roughly 70% of rated. The "loss" is more like 30% than 3%.

Bob

[viking1]

The new thousand watt Vitron charger/inverter that comes in the 2021 may have some upgrades we don’t know about. We picked up our new trailer in October with two new Interstate batteries which I have been thrashing at least a dozen times because I plan to upgrade to lithium within the next week or two. I take the batteries down to 11.5 which happens on the second night of running the furnace while boondocking. Then later when I stop at a campsite with shore power both of my battery indicators jump to 14.4 for a few hours then back down to 13 something. (One indicator is in the bathroom and one above the kitchen sink)
I am not sure why this happens except that maybe the charger senses that a equalizing charge is necessary? This makes me wonder what will happen when I soon drop in two 100 amp lithium batteries. Clearly the Vitron is capable of higher voltage to accommodate the needs of lithium. I was under the assumption that I would have to manually adjust the Vitron for higher voltage.

[daleyocum]

Originally Posted by viking1

The new thousand watt Vitron charger/inverter that comes in the 2021 may have some upgrades we don’t know about. We picked up our new trailer in October with two new Interstate batteries which I have been thrashing at least a dozen times because I plan to upgrade to lithium within the next week or two. I take the batteries down to 11.5 which happens on the second night of running the furnace while boondocking. Then later when I stop at a campsite with shore power both of my battery indicators jump to 14.4 for a few hours then back down to 13 something. (One indicator is in the bathroom and one above the kitchen sink)
I am not sure why this happens except that maybe the charger senses that a equalizing charge is necessary? This makes me wonder what will happen when I soon drop in two 100 amp lithium batteries. Clearly the Vitron is capable of higher voltage to accommodate the needs of lithium. I was under the assumption that I would have to manually adjust the Vitron for higher voltage.

Right, your charger switches to a higher voltage for bulk charging and then lowers the charge voltage for float when the batteries are full.

The charge pattern is different for Lithium.

Please, for the love of God, could we all just accept that if you get $2,000 worth of Lithium batteries you want to also get a $200 charger/ converter designed for them!

[viking1]

Originally Posted by daleyocum

Right, your charger switches to a higher voltage for bulk charging and then lowers the charge voltage for float when the batteries are full.

The charge pattern is different for Lithium.

Please, for the love of God, could we all just accept that if you get $2,000 worth of Lithium batteries you want to also get a $200 charger/ converter designed for them!

Thanks. But can’t the stock Vitron be adjusted for whatever higher voltages the Lithiums require?

[viking1]

Also, what charger is available for $200?

[uncle_bob]

Originally Posted by viking1

The new thousand watt Vitron charger/inverter that comes in the 2021 may have some upgrades we don’t know about. We picked up our new trailer in October with two new Interstate batteries which I have been thrashing at least a dozen times because I plan to upgrade to lithium within the next week or two. I take the batteries down to 11.5 which happens on the second night of running the furnace while boondocking. Then later when I stop at a campsite with shore power both of my battery indicators jump to 14.4 for a few hours then back down to 13 something. (One indicator is in the bathroom and one above the kitchen sink)
I am not sure why this happens except that maybe the charger senses that a equalizing charge is necessary? This makes me wonder what will happen when I soon drop in two 100 amp lithium batteries. Clearly the Vitron is capable of higher voltage to accommodate the needs of lithium. I was under the assumption that I would have to manually adjust the Vitron for higher voltage.

Hi

First off, you very much do *not* want to run your batteries down to 11.5V at normal temperatures. At 70 degrees out, something like 12 to 12.2 (depending on what you have) is the minimum you want to go to. Past that you risk damage to the batteries.

When it's cold out (and the batteries are cold) the "magic voltages" all shift up. If it gets quite cold, they might move as much as a half volt. Now your 12 to 12.2 is up around 12.5 to 12.7V. That makes 11.5 pretty crazy. Also if it's cold, the "normal" 13.6 (maybe) charge voltage should move up to 14.1(maybe). How much the voltages move depends on the actual battery temperature *and* the type of battery *and* the materials used on that specific battery. Turns out they make them different for hot climates vs cold ones ...

Without a temperature sensor on the battery, there is no way for a charger or converter / charger to know what's going on. That makes keeping up with all this a bit tough. In addition, the solar charger will sometimes get into the act. It always would go up to 14.x volts.

Equalize voltages as have been discussed are a good volt higher than any of this (at 70 degrees). At 30 (or -30) they might be quite a bit higher ....

Bob

[GettinAway]

Originally Posted by gypsydad

May have missed this, but which batteries are you using, how much were they, and where did you install them (inside or batterybox?) Also, what else did you need to install to use them? (cost?) Appreciate the input.

I bought two of the BB 100 amp hr batteries on the cyber Monday deal. They were $700. I had already made an appointment with Ronnie Dennis in Alabama to upgrade my converter, add a bms, and get the 3” lift. We also added the DILL TPMS at the same time, and a DC to DC charger for my truck. He redid the poor job of wiring I did when I installed the EasyStart, and got my 200 amp portable panels (Renogy) set up properly, with a 30’ extension. I was there for a day and a half. Around $3,000 (does not include batteries). I trust his judgement on where to put the batteries, which turned out to be in the front storage compartment. I confirmed the other day that even though it was 9 degrees, the batteries were fine.
You ended your question with the roll eyes.. Were you really wanting details?

The batteries were $700 ea. We are without hookups most of the tine we camp.

[TouringDan]

Originally Posted by viking1

Also, what charger is available for $200?

Here you go viking1.

I installed the 45 amp converter because I wanted to be able to charge the lithium batteries using the 1,000 watt generator in my Tundra.

Dan

[gypsydad]

Originally Posted by GettinAway

I bought two of the BB 100 amp hr batteries on the cyber Monday deal. They were $700. I had already made an appointment with Ronnie Dennis in Alabama to upgrade my converter, add a bms, and get the 3” lift. We also added the DILL TPMS at the same time, and a DC to DC charger for my truck. He redid the poor job of wiring I did when I installed the EasyStart, and got my 200 amp portable panels (Renogy) set up properly, with a 30’ extension. I was there for a day and a half. Around $3,000 (does not include batteries). I trust his judgement on where to put the batteries, which turned out to be in the front storage compartment. I confirmed the other day that even though it was 9 degrees, the batteries were fine.
You ended your question with the roll eyes.. Were you really wanting details?

The batteries were $700 ea. We are without hookups most of the tine we camp.

Yes, and thanks for "the details"! Not quite there yet with my 2 6V Trojans still doing a good job for our use model so far. Still interested in what will be needed if I do go Li. Seems my Boondocker 60 will work; but will need some additional wiring and perhaps a solar panel or 2 on top...that's the overall investment question..some folks here seem to go nuts on this project? not sure what is really needed for the switch.

From Dennis C "I’m considering adding two more 90W panels this spring, which would give me 360W on the roof. I’m also considering buying a Honda 2200 generator with a propane conversion. I’ll likely add an Easy Start to my air conditioner, although we usually camp in the mountains so this isn’t a top priority."

I did just receive my new Honda 2200 with the propane conversion from Genconnex and will be trying it out today. I looked at the DIY from Hutch Mountain, but the Genconnex was all done and is a cleaner design, plus the 3 year warranty! I will report back shortly..they included a 12' hose and "high altitude fuel orfice" kit at no charge also...

[viking1]

Originally Posted by uncle_bob

Hi

First off, you very much do *not* want to run your batteries down to 11.5V at normal temperatures. At 70 degrees out, something like 12 to 12.2 (depending on what you have) is the minimum you want to go to. Past that you risk damage to the batteries.


The resting voltage rate is between 12.5 and 12.7 after sitting for 20 minutes with nothing on and no external AC power. I've been taking them down to mid 11s just for the heck of it to see what would happen. I live off-grid so I know this will damage batteries, I was just curious. Next week I'll be tossing the Interstates and installing Lithium.


When it's cold out (and the batteries are cold) the "magic voltages" all shift up. If it gets quite cold, they might move as much as a half volt. Now your 12 to 12.2 is up around 12.5 to 12.7V. That makes 11.5 pretty crazy. Also if it's cold, the "normal" 13.6 (maybe) charge voltage should move up to 14.1(maybe). How much the voltages move depends on the actual battery temperature *and* the type of battery *and* the materials used on that specific battery. Turns out they make them different for hot climates vs cold ones ...


I don't have a volt meter with me to measure what passes through the 7-pin plug from the TV but both meters, sink and bathroom, read 14 volts and completely recharge my two Interstates in 2-3 hours. (I had my girlfriend ride in the trailer to monitor both meters as we drove) I've already heard that these numbers are odd. TV is a 2021 Mercedes SUV GLE 530 which has no fan belts or standard alternator. It does have a 48 volt electric booster motor so there is likely a powerful regeneration system. Please don't ask me anything about the cars charging system though because I am clueless. Mercedes techs don't seem to know anything about what happens to the car either once a trailer is plugged in but the system changes...probably for the better.



Without a temperature sensor on the battery, there is no way for a charger or converter / charger to know what's going on. That makes keeping up with all this a bit tough. In addition, the solar charger will sometimes get into the act. It always would go up to 14.x volts.

Equalize voltages as have been discussed are a good volt higher than any of this (at 70 degrees). At 30 (or -30) they might be quite a bit higher ....

Do you find it odd that my charger/inverter cranks up to 14.5- 14.6 on shore power?


Bob

Thanks again for your help

[viking1]

Originally Posted by TouringDan

Here you go viking1.

I installed the 45 amp converter because I wanted to be able to charge the lithium batteries using the 1,000 watt generator in my Tundra.

DanAttachment 385693Attachment 385694

Thanks amigo but given the complexity of my car I would not tamper with or add to the charging system that does seem adequate anyways. 14 volts while rolling down the road.