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400AH lithium cells? Best price per AH? $0.85/ AH?

15441 Views 216 Replies 12 Participants Last post by  sportcoupe
I'm looking to make a storage battery for a camper. Lithium is a better value for the money than lead IMO.

I want a 12v 400AH lithium pack as simple as can be. Fewer cells is better, isn't it? So, that's four 400AH cells I need plus a BMS.

I've heard prices are as low as $0.85/ AH if not in a hurry. Is that correct? Suggestion or comments?

Thanks!
-John
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Discussion Starter · #201 ·
That's odd because the user manual download has a lifepo4 configuration. :confused:


Charge Absorption Float Min Boost Max Boost
Switch position volts volts volts mins mins
1) Gel I 14.0 13.85 13.7 60 600
2) AGM I 14.1 13.75 13.4 60 480
3) Sealed 14.4 14.15 13.6 120 480
4) Gel II 14.4 14.0 13.8 720 1440
5) AGM II 14.6 14.1 13.7 60 480
6) Flood/open 14.8 14.0 13.3 60 480
7) Calcium 15.1 14.3 13.6 60 360
8) De-sulphation 15.5 0 0 240 240
9) LiFePO4 14.4 13.8 13.8 30 30
 

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Discussion Starter · #202 ·
I've done some long thinking and have changed my electrical loads moving aircon to genny only, mainly because I want a larger BTU unit. Cooking and coffee will be 100% propane. Heating and hot water will be petrol.

House battery can now easily drop to 300Ah and if I go FLA (or AGM), 300w - 400w solar is planned to be the primary charging method.

.
 

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Very sensible.

As long as you are monitoring SoC reasonably well, go ahead and oversize the bank, just do not draw more that what you can put back given conditions.

Not a good idea to add more batts later,

shallower cycling gives longer lifespan, and

it will tide you over better when conditions are bad.

Although being equipped to pump Bulk charge in via genny in the AM before solar starts will help get back to 100% Full a few days a week.

You can always add more solar later to reduce ICE charging runtime.
 

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Cooking and coffee will be 100% propane. Heating and hot water will be petrol.
Combo all in one water heater/air heaters are stupid expensive. I don't know why.

Reasonably priced means two separate units.
Air heater: Espar Hydronic II B5S Economy $667
Water heater: Eccotemp L7 Tankless $199
You do realize that the Eccotemp is propane, not gasoline, right? :confused: Or did you find a different L7?
 

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No need for an air heater if you rig a water heater aka hydronics,

will heat the living space via air exchanger, aka radiators

as well as provide hot water at the same time.

Usually tied into the engine block coolant loop
 

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Espar's the one I usually see

I assume also Webasto, Planar

maybe some Chinese knockoffs now, cheap enough buy an extra for a spare?

Some say they adapt the Ecco style instant propane as above, but likely not as fuel efficient

My main point is no need for both space hydronics and HWS the functions should be combined, and integrated into the engine block.
 

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Discussion Starter · #211 ·
The combined air/hot water Espar hydronic systems I see are either $4000 or diesel or both.

I do not see a single heating solution for air and water in a gasoline (petrol) van. I don't have any rv experience though. I'd like to use propane for cooking only as it's not exactly the cheapest and most plentiful fuel I have available. Gasoline is.
 

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You mentioned the Espar Hydronic II, choose the right model as your base.

For good value, figure out how to hook it up yourself, ideally not just online, but get a pro that charges a reasonable rate to help design, source parts.

But actual installation work is basic plumbing, save a lot doing that yourself.

Skoolie forum has some very knowledgeable guys posted howtos with pics, links to parts.

But yes not cheap if you want a whole complex setup like that all done for you, parts well under half the labor charges.
 

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Note in hydronics, the primary sources only heat the liquid.

Exchangers then output that heat, liquid to air, aka radiators for the air space, liquid to liquid for HWS.

Space heating can be passive, e.g. pipes embedded in the floor, radiator mounted on the wall, or active fans like those bus heaters.
 

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Discussion Starter · #214 ·
You mentioned the Espar Hydronic II, choose the right model as your base.
Duh me. I thought that one was ONLY air and not water. I had to take a double take look at it.

Having never installed one, I will research long before I drop $1500. It's still a lot of money, but it runs entirely on gasoline for one model. That's nice.
 
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