Lead Acid for Start and Lithium ION for house

[dale1]

greetings.

I know this has been discussed but im still not clear. can i replace the 4, 6v lead acid batteries on the house side with 2, 12v lithium ion batteries? and keep the lead acid batteries on the start side. thanks, dale

[twinboat]

Yes. Lithium batteries are not designed to start large diesel engines.

[dale1]

Thanks friend. I know that you know. So. I can keep my good 12v wet start batteries and install lithium house batteries without any mods? I just need to make sure the inverter charger can work with lithium batteries?
also, what about charging the house batteries with the engine alternator?

thanks again, dale

[vito.a]

Yes, but....
Most folks will tell you to disconnect the engine alternator from the lithium batteries. The theory is the lithium batteries will overtax the alternator and burn it out.
I'd recommend a Blue Sea ML-ACR for combining house and chassis batteries. This gives you control of when the batteries are combined.

The next problem is temperature, both cold and hot. You'll need a way to protect the lithium batteries from temperature extremes.
Good luck!

[astrnmrtom]

That's exactly what I have done. I disconnected my alternator and added a DC to DC charger. Pretty simple.

[dale1]

thank you all. i read last night until my eyes hurt on this subject it's like trying to push rope.

i'm not sure what the DC to DC charger is? I'll try to figure that out. I've got to use the coach this weekend. So, i guess I'll install new 6v Golf cart batteries for now. the old ones are on 2 years old and 2 of them have failed?

I was hoping for a simple upgrade but i don't think its that simple.

thanks again,
dale

[SteveJ.]

Originally Posted by dale1

thank you all. i read last night until my eyes hurt on this subject it's like trying to push rope.

i'm not sure what the DC to DC charger is? I'll try to figure that out. I've got to use the coach this weekend. So, i guess I'll install new 6v Golf cart batteries for now. the old ones are on 2 years old and 2 of them have failed?

I was hoping for a simple upgrade but i don't think its that simple.

thanks again,
dale

Can you not just limp around on 2 batteries for the weekend?

Changing over to lithium is a bit more involved than just dropping them in. Do some reading but you may or may not need a DC to DC charger to keep the battery systems separate, an updated shore power charging system, and temperature control. Charging for lithiums is a different ball game.

[twinboat]

Charging lithums with alternators will only charge them to 80%, not full. BlueSea switchs can't fix that.

A Battery to Battery ( DC to DC ) charger takes your alternator voltage and rises it so that the batteries will fully charge.
With that installed, you need to disable the original chassis to house charging system.

Most newer MHs have the ability to maintain the chassis battery from the house battery charging system. That can no longer be used because it will overcharge the chassis batteries. Buy and install a 120 volt chassis battery maintainer.

Your inverter/charger needs to be adjusted to fully charge the Lithium batteries and then stop charging when full. It's a different profile then lead acid batteries.

[Sinyyl]

Here is the simple version:
Yes, you absolutely can. If you don't want get too detail, just buy some quality name brand Lithium battery like Battleborn etc. and directly replace the old one. If will absolutely work and much bettery than 6v battery.


A bit more detail, the converter (turns 120v to 12v) probably changed to better suit the voltage of lithium battery. But the stock one will work still.
This topic can go on days, like dc-dc charger to charge house battery from alternator, 12v vs 24v vs 48v, inverter, solar panel, solar charge controller and so on, it can be a never ending project. But you can stop at just a drop in replacement.

[dale1]

Thanks much guys. I am entertaining Two of my riding buddies this weekend, so no time. I went ahead and purchased four new 6V wet batteries. We seem to Boondock two or three times per year. Usually six days per year so it’s no big deal. I would like to upgrade at some point. Four 6V battery is were 800 bucks :-(

[xrated]

Originally Posted by dale1

Thanks much guys. I am entertaining Two of my riding buddies this weekend, so no time. I went ahead and purchased four new 6V wet batteries. We seem to Boondock two or three times per year. Usually six days per year so it’s no big deal. I would like to upgrade at some point. Four 6V battery is were 800 bucks :-(

And just for clarification.....you will not be using Lithium Ion batteries, you will be using LiFePO batteries....shortened to LFP.

[freestyle_freddy]

Here's a ? I've never seen asked before. Is there a need or benefit to equalizing starter batteries. I've greatly extended the life of my house batteries in my 5th wheel by regularly equalizing them, but never thought about doing the same to my dual batteries in my 2017 F350 diesel dually. I know there's a difference between the two types of batteries. I believe starter batteries have much thinner lead plates than golf cart batteries, but I don't know how that relates to the need or benefit of equalizing them. My truck batteries are 6 years old & just starting to show a little weakness if they sit for a week between starting. There reading 12.5V after a 20 mile shopping trip into town, & 11.9V after sitting for a week. Does anyone else equalize starter batteries?

[153stars]

Start batts on alternator get recharged a bit on the high side and not cycled down to 50%, so not as much of an issue to have actual cell inbalance. There are desulfate settings on some chargers that do the same thing. Also dedicated desulfate/reconditioning chargers that send pings of higher voltage to desulfate without as much overcharging ,heat and gassing. You can find DIY diagrams to build your own. There are maintainers that supposedly run desulfate cycles but we're they built with enough energy to do it to a pair or four GC2 house batts . Probably best to proper care watering and keep bi-directional charging working as it should.

Originally Posted by freestyle_freddy

Here's a ? I've never seen asked before. Is there a need or benefit to equalizing starter batteries. I've greatly extended the life of my house batteries in my 5th wheel by regularly equalizing them, but never thought about doing the same to my dual batteries in my 2017 F350 diesel dually. I know there's a difference between the two types of batteries. I believe starter batteries have much thinner lead plates than golf cart batteries, but I don't know how that relates to the need or benefit of equalizing them. My truck batteries are 6 years old & just starting to show a little weakness if they sit for a week between starting. There reading 12.5V after a 20 mile shopping trip into town, & 11.9V after sitting for a week. Does anyone else equalize starter batteries?

[Sinyyl]

Originally Posted by freestyle_freddy

Here's a ? I've never seen asked before. Is there a need or benefit to equalizing starter batteries. I've greatly extended the life of my house batteries in my 5th wheel by regularly equalizing them, but never thought about doing the same to my dual batteries in my 2017 F350 diesel dually. I know there's a difference between the two types of batteries. I believe starter batteries have much thinner lead plates than golf cart batteries, but I don't know how that relates to the need or benefit of equalizing them. My truck batteries are 6 years old & just starting to show a little weakness if they sit for a week between starting. There reading 12.5V after a 20 mile shopping trip into town, & 11.9V after sitting for a week. Does anyone else equalize starter batteries?

I suppose your F350 is running 12V? In that case, you should not need to balance them because the 2x12V battery will be wired in parallel which means they are constantly balancing themselves. 6V batteries would be wired in series to make 12V, thus one of the 2 in a pack may be discharged more than the other.