Cinergi's 28 kWh / 4 kW Solar / 10 kW inverter RV build

Boondock Saint

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And it's a bit of a science experiment ... I'll better understand what my rig can do.

I'm not too far from you. Heading Westward?

Go ahead, push your rig to the limits, I live vicariously through your pioneering efforts!

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cinergi

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If your window coverings aren't excellent grade, that would be the first place I would start.

Yup. I very well may reorient myself today to keep the western sun off the long edge of the RV. New Horizons still owes me the awnings (they weren't available when I picked up the RV) so they're coming .. just... not when I need them! :)
 

cinergi

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I'm not too far from you. Heading Westward?

Go ahead, push your rig to the limits, I live vicariously through your pioneering efforts!

.

Yeah I'll do Devil's Tower and Rushmore next ... in a couple weeks.. after that, Yellowstone ... hopefully.
 

cinergi

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With 9k and 12k BTU and a fan I'm keeping the interior ~20 degrees cooler than exterior.. 77 max yesterday. I re-oriented the rig so the sun hits the short side. Batteries are another story. I can't keep them cool enough (93 yesterday). Today and tomorrow over > 100 so my short term solution is bags of ice and a fan in the basement lol. I even added the alcohol I keep in my freezer as sources of cold :ROFLMAO:. It's helping, but not enough. If I wanted to be in this weather for any period of time, I'd need to get an AC in the basement or move the batteries inside somewhere, somehow.

The Panasonic HIT panels are still nothing short of amazing even in this weather. 2300 watts (rated 3350) right now at 10am and 93F ambient and flat and smoke haze from the fires.
 

David S

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Move those batteries inside like mine and call it a "high tech coffee table" just over from the stripper pole.

Add some color changing LED strips that strobe with the douche music, put that sh*t on youtube.

Welcome to PIMP MY RV, Cinergi Edition.


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We need something like Reddit upvoting on this forum, just for comments like this :D
 

Luthj

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95F doesn't seem alarming to me, pretty typical ambient highs in many places, and within the operational spec of most LFP cells.
 

cinergi

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95F doesn't seem alarming to me, pretty typical ambient highs in many places, and within the operational spec of most LFP cells.

Oh? Maybe I'm mis-remembering. I thought they started degrading more quickly above 77F. I guess I need to hunt down some graphs.
 

Luthj

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I like to think of the batteries average temperature throughout the year not necessarily its peak temperature. Assuming the peak temperature is within the allowable range.

In my opinion it's acceptable to have the batteries at average ambient temperature for any application that is not going for extreme cycle life. So if an extra percent or two loss each year are acceptable, then roll with it.

I assume you aren't in tropical weather all year? So the cells will have several months in cold weather?
 

cinergi

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For reference: > 30*C seems to be pretty detrimental, let alone 35*C. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6126518/
Yes, I'm not charging at these temperatures frequently, but I definitely go above 25C frequently and year-round (I follow the weather in the RV). Probably covered in another thread here somewhere and/or would need a new thread, but .. yeah. I get it. I'd get roughly 3% degradation per 100 cycles if every cycle was 35*C+. If it's a handful of cycles, not as big a deal. I feel better. Thanks :)
 

Hedges

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You're running A/C anyway. Various options for ducting (depending on whether you want to risk electrolyte spray and magic smoke recirculating to RV interior), but you could divert a small amount of interior air to the inverter input and to an enclosure over the batteries. Maybe a fan with a baffle to pass cool air over them when the get warm. It could exhaust to the outside, a "single pass" air cooling system.
 

cinergi

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I've got 300 CFM of interior air blowing into the compartment. It's nowhere near enough.
 

Boondock Saint

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I just went through 2 sheets of 1/2" foil backed styro board and going back to buy more of that and 2 sheets of 1". Everywhere I put it is a noticeable difference.


.
 

Lt.Dan

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Time to get a window AC like I did lol. Best thing I did for that compartment. Quite power hungry unfortunately

EDIT: I should add, my batteries are in an enclosed aluminum case with no airflow, and right now the BMS says the temp sensor is at 35* C. I've never heard of degradation from that temperature though. I will need to do more research as well...
 
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cinergi

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Time to get a window AC like I did lol. Best thing I did for that compartment. Quite power hungry unfortunately

EDIT: I should add, my batteries are in an enclosed aluminum case with no airflow, and right now the BMS says the temp sensor is at 35* C. I've never heard of degradation from that temperature though. I will need to do more research as well...

Yeah I will probably have the leftover 9k cassette installed in the basement in November when I'm back at the factory...
 

Hedges

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I've got 300 CFM of interior air blowing into the compartment. It's nowhere near enough.

Maybe not enough to cool inverter dissipation to a comfortable level, but I think the dissipation of the batteries is less.
How about putting a box over the batteries and duct that 300 CFM over them first so they experience the coolest air.
That leaves the inverter to recirculate hot air. Next step might be to duct what passed over the batteries into the inverter (hope batteries never release noxious fumes) or duct exhaust of inverter to outside.
 

Lt.Dan

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For reference: > 30*C seems to be pretty detrimental, let alone 35*C. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6126518/
Yes, I'm not charging at these temperatures frequently, but I definitely go above 25C frequently and year-round (I follow the weather in the RV). Probably covered in another thread here somewhere and/or would need a new thread, but .. yeah. I get it. I'd get roughly 3% degradation per 100 cycles if every cycle was 35*C+. If it's a handful of cycles, not as big a deal. I feel better. Thanks :)
Cinergi, while poking around the interwebz, i found this chart for the CATL 280ah cells. Seems the working temperature is all the way up to 60*C. But i havent really found anything else stating degradation from heat in the cells other than the link you posted. Any more info for that?

I saw my batteries up at 41*C last night when the battery was just about 5% SOC and had a heavy load on it, and you're starting to worry me!
spec-1.png
 

cinergi

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Cinergi, while poking around the interwebz, i found this chart for the CATL 280ah cells. Seems the working temperature is all the way up to 60*C. But i havent really found anything else stating degradation from heat in the cells other than the link you posted. Any more info for that?

I saw my batteries up at 41*C last night when the battery was just about 5% SOC and had a heavy load on it, and you're starting to worry me!

I stopped looking after I realized, at my temps, it's 3% degradation if I did it every day all year, and I don't. 41 seems pretty high so it might be worth trying to find information for those temps (the article I quoted only goes up to 30 lol)
 
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