Dump Deep Cell and go to Lithium???

[THenne1713]

I expect will b interesting, if you understand that the RC of a deep-cycle is a Rating in MINUTES of how long BATTERY CAN HANDLE 25a. LOAD before dropping below 10.x-volts?... and (most Lead acid) RC ratings= LESS that 200

 

[Just two]

New batteries put to the test

Just did an important test on the lithium batteries install in our BT5210. Using the new batteries and the 3000 watt inverter, I was able to roast 2 lbs of coffee. The batteries are totally charged by solar. This proves we will be ok boon docking at least having fresh roasted coffee. That is important.

 

[WSmith]

Nice!
I am seriously looking at a BT5210/5230 and would make similar changes to Lithium.
How many Lithium Batteries (looks like 4 x 200Ah) but where did you mount them?
Did you need to change the Power Panel (do you know the std panel model as used in the BT)? Converter?
What is your solar system set-up?
Thanks in advance.

PS: I am looking at 200W Solar with Go Power, 270Ah Battle Born assuming it fits in the current battery area (I don't know how may batteries fit in current storage area) - 2000W/3000W Inverter - Not sure about the converter as I do not know what os used now. My closest dealer is a 6hr RT drive.

 

[proost]

Yep... this is why I WON'T go the route of Lithium. I am not going to rebuild/purchase a whole new system for a 2021 unit where everything is new at this point.

I think I am going to add two more batteries, Renogy AGM gel. That would give me 4 batteries... 2 that are 80 ah and 2 that are 100 ah.

Prices are being forced down because of some healthy competition out there. www.redodopower.com sells them for ~$200 each and the quality of build is high per Will Prowse who routinely breaks these things down and does open/inspects for quality. The days of $1000 batteries are over.

 

[Just two]

WSmith, I removed the dinette from behind the passengers seat. Built a single bed there. The 4 big batteries are under that bed. The other side has a matching bed over the fresh water tank.
The 12 volt system AGM I replaced with 2 12 volt Lion Safari lithium. Both batteries fit in the original spot. I bought a B2B to charge them off the alternator but never installed it. They charge great with the existing Gulf Stream system.
About charging in the cold, we have had temperatures in the single digits and the batteries under the floor (12 volt) in the cold have issues getting fully charged. The big batteries (24 volts) on the inside haven’t had any problems.
I did change the battery charge system under the fuse box. Got one for lithium off Amazon. It works fine.

 

[Just two]

The controller that I purchased. Working great. Now $120. Fan is a little loud.

 

[WSmith]

WSmith, I removed the dinette from behind the passengers seat. Built a single bed there. The 4 big batteries are under that bed. The other side has a matching bed over the fresh water tank.
The 12 volt system AGM I replaced with 2 12 volt Lion Safari lithium. Both batteries fit in the original spot. I bought a B2B to charge them off the alternator but never installed it. They charge great with the existing Gulf Stream system.
About charging in the cold, we have had temperatures in the single digits and the batteries under the floor (12 volt) in the cold have issues getting fully charged. The big batteries (24 volts) on the inside haven’t had any problems.
I did change the battery charge system under the fuse box. Got one for lithium off Amazon. It works fine.

Then, if I have a 5210/5230 with two jack-knife sofas, I would need to modify/change the one behind the passenger seat in order to place some Lithium batteries and inverter?

 

[WSmith]

The controller that I purchased. Working great. Now $120. Fan is a little loud.

Why did you upgrade the Converter to more A? Did you install it inside the power panel? What brand/model is the factory supplied Power Panel in the 5210? Thanks

 

[Just two]

The factory converter is setup to charge lead batteries. Lithium have a higher voltage and different charge profile. To match the lithium house batteries and get the best performance it was better to change it.

 

[THenne1713]

So recently reading that Cell Phone Lithium gets extended life if charge limited to 85% vs 100%? Does this apply to RV 12vdc lithium also? What is actual field experience of RVers?

 

[proost]

So recently reading that Cell Phone Lithium gets extended life if charge limited to 85% vs 100%? Does this apply to RV 12vdc lithium also? What is actual field experience of RVers?

Will Prowse on YouTube and on his site DIY Solar Power Forum goes into this and does a bunch of testing. Here's a helpful video on exactly this topic you've brought up:

Basically, LiFePO4 batteries you see in RVs are significantly different than Li-ion you see in other devices like phones, etc. You definitely need to charge your LiFePO4 batteries to 100% to keep the bank balanced but then you also should plan on discharging them routinely to keep them healthy. In the standard operating cycle, Will advocates working your bank towards an average state of charge of 50% but that includes routinely charging to 100% to keep them balanced but also discharging them down while you're on solar. Essentially, exercise them. Even if you don't cycle them fully or keep them fully charged longer (like we do when we're on the grid), the degradation over time is so minimal, we'll never notice. These things are designed to last safetly for 20+ years and can handle the variance in usage.

We've got 10 LiFePO4 batteries and have been running a solar setup in our coach for six years full-time. We love them. Hope this helps and lemme know if you have any questions about my experience with them.