Will a 30AH LITHIUM ION BATTERY work for me?

[Tom55555]

It would probably work but an inexpensive 100 Ah lead acid deep cycle battery would do better. The only down sides are weight and you need to check water levels every 6 to 12 months.

 

[Gary RV_Wizard]

Is anybody making a converter for such RV house batteries yet?

WFCO has a line of lithium-compatible converter/chargers.
https://wfcoelectronics.com/lithium-solutions/

 

[DonTom]

It would probably work but an inexpensive 100 Ah lead acid deep cycle battery would do better. 

Better at keeping the voltage above ~12.5 VDC after a couple of hours of boondocking?


That is my main interest in switching to LitIon.




-Don-  Yuma, AZ

 

[Lou Schneider]

I know about not letting them discharge to the point that they become bricks. The same can happen to my electric motorcycle batteries, but unlikely as they are many KWhs and don't self discharge much--but it can still happen with enough neglect over a long time period,  when left somewhat discharged to begin with.

-Don-  Yuma, AZ

Bricking is only a practical problem if you DIY a battery out of individual cells.  All of the commercial batteries have an internal Battery Management System (BMS) that disconnect the loads before the battery gets low enough to brick it.  The only way to kill one of these is to draw it down until the BMS shuts it off,  then leave it that way for several months.

There's nothing mysterious about a Lithium charger. LiFePo batteries require 14.1-14.6 volts to charge to 100% capacity.  Both WFCO and Progressive Dynamics have converters that will do this.  But 13.6 volts from a standard RV converter will fill a LiFePo battery to 85-90% at a good charging rate. Higher if it's a multistage charger that already boosts the voltage to 14 volts or higher during the charging cycle.  My Lion Safari batteries draw about 25 amps each at 13.5 volts until they're full.  The last 10-15% can be ignored (partial charging not only won't hurt the battery, it will actually extend it's life because staying at 100% charge can make the positive anode brittle) or it can be made up by a solar system or other source set to the higher voltage.

 

[DonTom]

WFCO has a line of lithium-compatible converter/chargers.
https://wfcoelectronics.com/lithium-solutions/

Thanks, I see they even have a switch to change from lead acid to Li-Ion. Sounds perfect.


-Don-  Yuma, AZ

 

[DonTom]

The biggest issue I see is that I only have room for 100AH in my battery compartment. They jump in size from 100AH to 200AH. I would probably have enough room for around 120 to 150 AH, if such were made in Lith-Ion.


I see that 90% of its charge stays  above 12 volts. 50% for lead acid to stay above 12 volts.


-Don-  Yuma, AZ

 

[DonTom]

Bricking is only a practical problem if you DIY a battery out of individual cells.  All of the commercial batteries have an internal Battery Management System (BMS) that disconnect the loads before the battery gets low enough to brick it.  The only way to kill one of these is to draw it down until the BMS shuts it off,  then leave it that way for several months.

Yes, same with the electric motorcycle batteries, but they are probably even worse. There is a contactor (large relay) inside the battery. It must close for the battery to be used period, and that means to charge as well. If the contactor cannot close, it's then a very expensive brick. The only time it is open is when the bike is not used to do anything at all. Key off and not charging. The power for the contactor must come from the battery itself for the charger to start charging. However, in this case, we're talking about many KWHs which takes quite a bit of time to self discharge, as there is NO load at all  when the contactor is open. They say to store it at 60% SOC and check it twice  per year and only recharge when below 30% SOC. Mine will stay as 60% for months (such as this RV trip that I started in early November and won't be back until next month).

There's nothing mysterious about a Lithium charger. LiFePo batteries require 14.1-14.6 volts to charge to 100% capacity.  Both WFCO and Progressive Dynamics have converters that will do this.  But 13.6 volts from a standard RV converter will fill a LiFePo battery to 85-90% at a good charging rate. Higher if it's a multistage charger that already boosts the voltage to 14 volts or higher during the charging cycle.  My Lion Safari batteries draw about 25 amps each at 13.5 volts until they're full.  The last 10-15% can be ignored (partial charging not only won't hurt the battery, it will actually extend it's life because staying at 100% charge can make the positive anode brittle) or it can be made up by a solar system or other source set to the higher voltage.

My Progressive Dynamics will do above 14 volts in the boost mode, which I can manually switch to at any time. Are you saying there is no real need to change my power converter and I can get by with only changing my battery to Lith-Ion?


Same with the cycle batteries. Best to not leave them charged at 100% SOC for long. As well as my Tesla Batteries.


-Don-  Yuma, AZ

 

[Tom55555]

Better at keeping the voltage above ~12.5 VDC after a couple of hours of boondocking?


That is my main interest in switching to LitIon.




-Don-  Yuma, AZ

Lithium is better if you don't mind spending the money. I use them on our e-bikes because of weight.

I've used standard 100 Ah lead acid deep cycle batteries for 20 years in our RV. If it runs low, I just start the primary motor or generator.

 

[DonTom]

Lithium is better if you don't mind spending the money. I use them on our e-bikes because of weight.

I've used standard 100 Ah lead acid deep cycle batteries for 20 years in our RV. If it runs low, I just start the primary motor or generator.

No, I don't mind the cost. In fact,  I just wish I had the room for a larger one. Looks like I am stuck with 100AH, which isn't much. They are light, but not all that small for the AH capacity.


I cannot always run the generator when I want, such as where I was boondocked a couple of weeks ago for ten days at Organ Pipe Cactus National Monument, Twin Peaks Campground. Gen hours there are from 0800 to 1000 hrs and from 1400 to 1600 hr.


However, my generator crapped out there on my 2nd day, so I had to run the RV engine to charge my house battery. And they even have time limits on idling an RV engine  there. ten minutes, IIRC. So I idled my engine when all the generators were running to keep my battery charged.


My genny crapping out is mentioned in the tech section here.


-Don-  Yuma, AZ

 

[AStravelers]

No real need, other than curiosity. Such as when my refrigerator is on propane, how much DC current is it then drawing?

-Don-  Yuma, AZ

Your fridge when switched to propane will use about 0.1A when not cooling.  When the control board picks the propane valve the fridge will pull about 0.2A. 

Good quality battery monitors such as Trimetric or Victron will display the amps down to 1/10 of an amp.  Usually an RV will have a phantom amp draw from 1/2amp to several amps, so turning off and on the fridge you should see the amps change by one or two tenths of an amp. 

 

[cerd]

During the summer, a single 100AH lead-acid works fine for me. If I turn the heat on in the fall, the battery only lasts one night. I am going to add 1 or 2 more this spring.

 

[Goodspike]

During the summer, a single 100AH lead-acid works fine for me. If I turn the heat on in the fall, the battery only lasts one night.

I don't have that problem since my furnace is too loud to run at night!    8)

Seriously, thanks for that.  I've yet to be out in colder weather in my trailer without electrical hookups.  That's sort of what I was expecting though.

 

[DonTom]

During the summer, a single 100AH lead-acid works fine for me. If I turn the heat on in the fall, the battery only lasts one night. I am going to add 1 or 2 more this spring.

I would also add at least one  if I had the room.  I don't have such room, in my battery box.  Any known fix for that?


With twice the battery to charge, will the charge times also be double? I assume it depends on if the voltage drops--a larger converter that can handle more amps could be needed that can handle more charge current, if you don't want to wait twice as long to charge.


I can drain my house battery faster boondocking with my ham radio stuff. Such as when I was in Organ Pipe Cactus National Monument.  The nice thing about boondocking there is, not much heat is needed during the night, if any, even in December.  I just wish I could run the generator or engine any time there during the day--as in Death Valley.


-Don-  Yuma, AZ

 

[Goodspike]

I would also add at least one if I had the room. I don't have such room, in my battery box. Any known fix for that?

Buy a second battery box and relocate the existing box to center, then get two lead acid deep cycle golf cart batteries.

Edit: They also make double long battery boxes.

Amazon.com: Camco Heavy Duty Double Battery Box with Straps and Hardware - Group GC2 | Safely Stores RV, Automotive, and Marine Batteries |Durable Anti-Corrosion Material | Measures 21.5" x 7.4" x 11.2" - (55375): Automotive

Amazon.com: Camco Heavy Duty Double Battery Box with Straps and Hardware - Group GC2 | Safely Stores RV, Automotive, and Marine Batteries |Durable Anti-Corrosion Material | Measures 21.5" x 7.4" x 11.2" - (55375): Automotive

www.amazon.com

 

[Tom55555]

We've boondocked when temperatures at night were 20 below zero and above 90.

Lots of National parks have those no generator rules after a certain hour. They don't enforce it when it gets really cold.

Above freezing, we just conserve energy meaning no TV and just using the little stove light. Our 100 Ah lead acid coach battery will run the heater, refrigerator, water pump, bathroom light & fan, our tablets and phones.

When we go into really hot and humid weather like Alexander Springs, Florida we cool our RV with our generator until cutoff time. If it gets too hot in the middle of the night; our Ford 5.4L gasoline primary motor is so quiet at idle no one can hear it and the AC works great especially with no sun. You only need to run it for 15 minutes. I've never had a ranger tell me to turn it off or a complaint.

 

 

[Goodspike]

When we go into really hot and humid weather like Alexander Springs, Florida we cool our RV with our generator until cutoff time. If it gets too hot in the middle of the night; my Ford 5.4L gasoline primary motor is so quiet at idle no one can hear it and the AC works great especially with no sun. You only need to run it for 15 minutes. I've never had a ranger tell me to turn it off or a complaint.

What does that do for you?  Just sit in the truck?

The new F-150 Hybrid would allow you 3,700 watts (or something like that) of 120 volt power.  Not sure if maximum power draw means the engine will rev higher than idle--I've not seen a review of that in operation.  Seems like a very inefficient way of generating power, and it would suck the fuel you need to get back to civilization, but it would do in a pinch.

 

[cerd]

I would also add at least one  if I had the room.  I don't have such room, in my battery box.  Any known fix for that?

Not sure what would work for you, but my current battery is in my storage compartment below the rear bunk. I no longer have an onboard generator, so I am going to remote locate the batteries in a box outside in the generator compartment. A little creativity goes a long way as long as you know basic electrical and mechanical skills.

With twice the battery to charge, will the charge times also be double? I assume it depends on if the voltage drops--a larger converter that can handle more amps could be needed that can handle more charge current, if you don't want to wait twice as long to charge.

Indeed, double the capacity will take longer to charge. You could upgrade your converter, but it won't do anything for you while boondocking since you don't anything to plug into. I would recommend just plugging in an automotive battery charger when you get back. If your alternator has a high enough output, you could upgrade the wiring from the alternator to charge the batteries in a MH. Mine is only 105A, so I can only charge about 20-30A without dropping voltage for the rest of the vehicle. But when most of our travel times are about 3 hours one way, that should be plenty for me to charge them.

 

[cerd]

What does that do for you?  Just sit in the truck?

The new F-150 Hybrid would allow you 3,700 watts (or something like that) of 120 volt power.  Not sure if maximum power draw means the engine will rev higher than idle--I've not seen a review of that in operation.  Seems like a very inefficient way of generating power, and it would suck the fuel you need to get back to civilization, but it would do in a pinch.

Can't confirm, but I would assume OP is referring to a MH and using the engine HVAC to control the cab temp. It works in a pinch, but I wouldn't trust it on an older rig without a good emissions system. You definitely don't want those NOx gasses getting into the cab.

3700W from an alternator would be 250-300A. I am skeptical of those numbers. Usually that means dual high output alternators, which would likely need a high idle switch like the trucks with PTO options. Most alternators don't put out full capacity until at least 1500rpm and most modern vehicles idle between 500-800rpm without the high idle switch.

 

[Tom55555]

Can't confirm, but I would assume OP is referring to a MH and using the engine HVAC to control the cab temp. It works in a pinch, but I wouldn't trust it on an older rig without a good emissions system. You definitely don't want those NOx gasses getting into the cab.

3700W from an alternator would be 250-300A. I am skeptical of those numbers. Usually that means dual high output alternators, which would likely need a high idle switch like the trucks with PTO options. Most alternators don't put out full capacity until at least 1500rpm and most modern vehicles idle between 500-800rpm without the high idle switch.

Cerd, you are correct.

It's five years old so it has a NOx, smoke and propane detector and the front HVAC on a Ford E350 is pretty good and it charges the starter and coach battery (155 amp alternator). 55 gallons of gas and 18 gallons of propane go a long way. The only thing I loose is our microwave because I only have a 300 watt invertor.

The point I was trying to make is the primary motor is so quiet you can run them at no generator times.

 

[cerd]

The only thing I loose is our microwave because I only have a 300 watt invertor.

I don't use mine just because the only thing we ever use it for is microwave popcorn. But my wife prefers smart food cheddar popcorn more anyways, so I just took it out for more storage. Our coffee maker runs off of the burner on the stove. We use a small inverter for the TV at bedtime for the kids, otherwise we don't need electric for anything except AC in the middle of the summer to keep the dogs cool while we are out.