Lithium vs. flooded banks for beginners
Note: for comparison purposes there’s a link in the text below to Trojan batteries on Amazon. Buy them locally to get the best price. There’s no shipping and you’ll be able to trade in the old cores.
From a thread on /r/vanlife:
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Thank you for the thoughtful response.
I don’t disagree with your technical analysis. I am pushing back on ideas like lead is “cheapo”, that Li is “doing it right”, and that large power storage capacity is necessary for “actual living”.
I think it’s worth talking about in public a bit more to help new folks make their own decisions. Not digging at you personally.
lithiums can get some insane cycle counts makes it an extremely cost efficient purchase when you look at it long term
Yes, it can make them an extremely cost efficient purchase, if you get those cycle counts. No one living in a van has ever done that yet, to my knowledge. To the contrary, early adopters like Technomadia found that real world RV temperatures caused early and significant capacity degradation. The person who has the most experience and most empirical data on LFP for nomads says:
"Almost every RV installation I have seen has been rather murderous to LFP batteries in use or execution/installation." -- [mainesail](http://www.cruisersforum.com/forums/f129/lithium-batteries-or-agm-194029-2.html#post2522585)
Let’s compare the two flagships: 2x 6v Trojan T-105 flooded and Battleborn LFP. For our purposes they have roughly equivalent capacities when the FLA [flooded lead acid] is cycled 50% and the BB 100%.
The BB costs ~4x as much as the T-105 bank.
The T-105 deep cycled to 50% DoD every day and recharged to manufacturer’s specs will typically last 1200 cycles (3.2 years) without special treatment. We have real world examples of careful owners getting much longer use out of them, 5+ years. They are also very robust in the face of abuse.
Limiting our discussion to duty cycles, the BB would have to last 12.8 years (longer than the BB warranty, assuming BB exists in 10 years) just to break even. Not sure how long it would take to get it into the “extremely cost efficient” range, maybe 20 years? How long will a newcomer actually live in a van?
LiFePO4 have such outstanding qualities (for those that need them) that we don’t have to sell them as cost efficienct, and we don’t have to scare folks off lead with FUD. Horses for courses. I am of the opinion that most vandwellers (and particularly beginners) are better served with a regular horse at a regular price than a $$$ thoroughbred.
[Edited to add: 1 battleborn battery, as fine as it is, costs more than my entire power setup: 570w, 40A mppt charge controller, voltage-sensing relay, and 220Ah GC2.]