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Old 09-23-2019
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RVinCT RVinCT is offline
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Join Date: Jan 2018
Location: Rockfall
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Originally Posted by NoGas View Post
Excellent recap! The only important piece of information missing is cost. How about a recap of that?

IF you can handle their up front price and one does not use them in extremely hot or cold conditions there’s no question Lithiums are the way to go. For a CT coach, putting them inside the old plastic battery tub might work for the winter cold in a heated bay. But doing that definitely would not be the way to go for a coach that operates in extreme summertime desert temps (without supplemental cooling). Not sure how manufacturers are advertising such wide operational temperature ranges. I find them hard to believe. The lithiums in my scooter will not change properly above 105 degrees. Also, I don’t think I’d risk taking their SOC below 20%. That’s what I set on my scooter and 10 years later they’re still working fine. The deeper you draw lithiums down, the greater the risk of “bricking” the pack - i.e. turning them into very high priced bricks.

With your new battery setup I am curious why you are still messing around with LP gas and that old ice cream melter?
Cost:
You'll have to contact Lithionics. I agreed not to disclose the pricing they gave me. I can't tell you why they required that. If you say you are putting them in a BlueBird and mention my name, they will at least know something about your project. However, I can say that I had hoped to come in under $10 per AH and did not succeed.

Temp: I agree that our experience in New England makes lithium batteries a particularly good fit for us. We mostly have to worry about cold temp charging problems, not heat. Lithionics sells a cold weather kit, which I did not purchase. I don't know if it can be retrofitted.

The claimed charge temp range is 32°F to 113°F. The claimed discharge range is -4°F to 131°F. I can't comment on whether those numbers are accurate. This description of my installation is not intended as a recommendation for others. With only a week to install them, I didn't have time to worry about insulation or heating cooling systems, but if I was desert camping in the heat, or winter camping in NE there are lots of improvements I would make.

Discharge range:
The battery chemistry is constantly being tweaked, so I can only go by the manufacturers recommendations. Battery life cycles in lithium testing differs from lead acid testing. The lithium cycle test is done around 50% SOC state of charge.

So for a 10% discharge life cycle test they go from 45% to 55% SOC. This can be seen as a lithium disadvantage. They like to be half discharged and will last longest if cycles around that point. That greatly reduces the effective capacity if you keep them only half charged. I tend to go 85% to 35-40% or less. It's hard to give up my old lead acid mentality of wanting to charge to 100%. .

The batteries, even when just being stored, should get an occasional full charge discharge cycle at least every 6 months. The discharge goes down to the LBCO low batt cutoff voltage. That's at 0%. I see the capacity as being chosen to allow cycling around a lower middle point, but allowing me to fully charge and more deeply discharge when I need lots of power in special situations, like powering the absorption refer or if I was having gen trouble.

As to absorption refrigerator and propane. You will pry them from my cold dead hands before I give them up for a battery draining, park side-by-side campground cause I need shore power to run the "residential" refrigerator.

Yes, it would work to put in a residential, but the quiet absorption that runs on either fuel is my ideal. We spent 2 years looking for an RV with an absorption fridge that meet our other requirements. My last ice cream was nicely hard and I have no concerns about starting a 4 month trip with $500 of frozen meat in my freezer.

I'll address why I chose Lithionics and not other suppliers or DIY battery construction from a supplier like Manzanita in a later post.
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Todd and Karen Pattist
Rockfall, CT
2007 Double Slide M380 "Bertie"
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