Buy acid battery or switch to lithium

[patvogelman]

2019 Montana 3121RL
Time to replace my 12v group 27 acid batteries (2)
Was looking at making the change to lithium battery for more capacity and longevity. Expert Power Lifepo4 100ah with 20ah lithium charger.
Question: Is there any changes you have to make to accept different batteries.
What about truck charging when traveling?
Do you have to change the converter in the Montana ?
Also if we buy a generator is there any specific type?
Would like a little Honda if compatible.

[Daryles]

2019 3121RL.
You probably have a Progressive Dynamics
PD4575K18LS8. The model number is on a white sticker inside the circuit breaker panel door. I have a 2019 3130re. That's the converter I have. It is not lithium ready. However it does have a charge wizzard and a mode switch you can set it to boost mode and get 14.4vdc for 4 hours. Lithium prefers 14.6vdc.
I have 552Ah of lithium batteries running with this converter for the last 2 years. Works fine. You just don't get quite topped off to 13.6vdc (100% for lithium).
I added 400W solar panels (2 ×200w) and a Victron MPPT 100/30 charge controller. It is set on lithium and brings them all the way up to full charge.
We went boondocking on the OuterBanks of NC for 5 days. We ran out of water. Never ran out of power. Batteries were full by noon.
As for truck charging. The most I have seen via the 7 way cable is about 7A (using a Victron BMV-712 battery monitor).
I installed a Renogy DC-DC charger for charging going down the road or when going on a short boondocking trip and don't want to drag the generator along.
Here's the write up on that.
https://www.montanaowners.com/forums...hlight=charger

[rames14]

I believe your charger is already lithium. Just change the charge profile in your converter (it will be in the converter/charge manual). Truck charging (real charging) falls into Dc-Dc chargers and BIM. You can find plenty of discussions on that by searching. We have the BIM. There are also lots of generator discussions without a right answer - it depends what you want to do - run everything, charge batteries, etc. We use two Honda 2000’s in Parallel with a 6 gallon center feeder tank.

[patvogelman]

Thanks for the info. I do have the progressive dynamics you listed so I should be okay. What size dc-dc charger are you using? I have a 220 amp alternator and wasn’t sure how many amp charger to get was thinking 40 amp should do. Just starting out with one 100ah lithium battery to replace my old acid batteries.
Thanks again

[patvogelman]

Thanks for the info. Honda’s in the future replacing old acid batteries want to invest in lithium lower cost over time.

[Daryles]

Originally Posted by patvogelman

Thanks for the info. I do have the progressive dynamics you listed so I should be okay. What size dc-dc charger are you using? I have a 220 amp alternator and wasn’t sure how many amp charger to get was thinking 40 amp should do. Just starting out with one 100ah lithium battery to replace my old acid batteries.
Thanks again

This is the write up of my DC-DC charger install
It has all the details.


https://www.montanaowners.com/forums...hlight=charger

[bcrvman]

Originally Posted by patvogelman

2019 Montana 3121RL
Time to replace my 12v group 27 acid batteries (2)
Was looking at making the change to lithium battery for more capacity and longevity. Expert Power Lifepo4 100ah with 20ah lithium charger.
Question: Is there any changes you have to make to accept different batteries.
What about truck charging when traveling?
Do you have to change the converter in the Montana ?
Also if we buy a generator is there any specific type?
Would like a little Honda if compatible.

There is a lot to consider in your questions, but it really depends on if you need to go to the expense of LiPo4 or not.
If you are a full timer then get Lithium, if not you probably will not realize all the benefits of an investment likely to be closer to $5,000 than not.
However the specific answers are
If you are getting a pair of 100AH x 12V then you want a charger of at least 50A better is 100A.
Different batteries generally mean different chargers but most good one's can be set to any type. Lithium is very forgiving as well.
Truck charging can be done but it's tricky. Done wrong can melt your alternator. Get expert advice from a Victron dealer.
I removed the converter because if you are full time and need Lithium, then you need an Inverter/Charger. Many full timers use the Victron Multiplus 12/3000/120-50 120V or the newer version. Those numbers mean 12V battery vs 24V, 3,000W or 2,400VA, 120A charger, 50A pass thru 120VAC system.
I use a pair of Honda EU2000i. You want an inverter type gennie if you have sensitive electronics. There are brands that have ripped off Honda and Yamaha for less money.
Best advice is find a solar dealer to guide you.

[rames14]

Your two group 27 lead acid batteries gave you about 88 usable amps (2 batteries, 88 amps each, 50% usage to avoid battery damage). One 100 ah lithium just upgraded your power (slightly), without voltage loss like a lead acid, with quicker recharge times. Battleborn had their 100 ah on sale for under $800 at rally. The question you have to answer is how do you use your rig? No boondocking, no question - lead acid. Boondocking occasionally - toss up. Lots of boondocking - lithium and build your system as you can afford it. Best of luck. Do what works for you.