Tesla announced powerwall2 pricing of $5500 for 14kw battery bank with an inverter. Seems to me a factory reconfiguration of the battery pack to 12vdc would provide an ideal house battery for boats and RVs... Obviously the bank could be scaled for smaller load demands... Cool stuff.
Powerwall 2 14 kwh with inverter < $6k
- Thread starter Ka_sea_ta
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That price is getting better, but 14 kw is really way too big for a house bank.
14 kw is about 1,200 Ahs at 12v. One of the selling points of a lithium battery system is that it can be routinely discharged to near zero and easily recharged to 100% unlike FLAs.
FLAs really effectively cycle between 50 and 85% whereas lithiums probably can be cycled between 10 and 100%, giving almost three times the effective capacity.
So a 1,200 FLA bank which would be rather big for a boat system is equivalent to a 400 Ah lithium bank. If the cost of a 400 Ah lithium bank is near 1/3 the cost of a 1,200 Ah bank then it is getting much closer to the cost of FLAs.
AGMs supposedly can be discharged deeper than FLAs, but I haven't seen any manufacturer data to back that up. But if true and assuming a 30-90% cycle, the lithium bank is even more competitive with AGMs.
I never thought I would see the day that lithiums would compete for the marine house bank business, but it is getting closer it seems.
David
14 kw is about 1,200 Ahs at 12v. One of the selling points of a lithium battery system is that it can be routinely discharged to near zero and easily recharged to 100% unlike FLAs.
FLAs really effectively cycle between 50 and 85% whereas lithiums probably can be cycled between 10 and 100%, giving almost three times the effective capacity.
So a 1,200 FLA bank which would be rather big for a boat system is equivalent to a 400 Ah lithium bank. If the cost of a 400 Ah lithium bank is near 1/3 the cost of a 1,200 Ah bank then it is getting much closer to the cost of FLAs.
AGMs supposedly can be discharged deeper than FLAs, but I haven't seen any manufacturer data to back that up. But if true and assuming a 30-90% cycle, the lithium bank is even more competitive with AGMs.
I never thought I would see the day that lithiums would compete for the marine house bank business, but it is getting closer it seems.
David
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Jeff F
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I read an article this morning where an automaker was quoted at saying their cost for Lithium Ion batteries is now down to $145/kWh. When I bought my EV under three years ago the cost was reported to be more than double that. Still lots of concerns over battery management and risk of heat/fire, but the rapid progress on resolving these issues is going to continue.
sbu22
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What Brooksie said. I don't see the average boat owner adding Class D extinguishers. Will that be in copper, graphite, TEC, or THD, Captain? I think the rec boat application is still well over the horizon.
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Sounds about right for me.
I have 8 x 220ah @ 12v = 1760 now
so 880ah @ 24v giving 2 days autonomy.
A couple of days extra wouldn't go astray, I could piss off this puny 3 burner smev gas oven and get in a decent sized electric oven in its place.
Unfortunately, your $5500 there will be more like $20,000 here.
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