Chinese Li-ion batteries for RV

Some one on the Teardrop &Tiny Travel Trailer forum asked if any one had experience with Chinese Li-ion batteries. Smaller less weight... The question is this https://dmdinverter.en.alibaba.com/product/60536302549-804800430/Deep_cycles_2000_times_ultra_light_ultra_thin_12v_lithium_panel_energy_storage_solar_battery_200ah.html?spm=a2700.8304367.0.0.bJQ9DU A real life possibility and what are the down sides.
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|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
https://batterybro.com/blogs/18650-wholesale-battery-reviews/104619270-can-you-identify-the-fake-lg-hg2-18650-battery
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
Having said that, I'm only a very interested observer of all the Li Ion battery technology. However there are several *REAL* experts here and you should probably pay some attention to them.
There are a lot of RV's that use Lithium Iron Phosphate (LFP) batteries. There are basically 2 types. There are manufactured 12 volt packs, usually 100 amp hour, but they can be installed in parallel for more amp hours.
https://www.solar-electric.com/battle-born-bb10012-100ah-12v-lithium-battery.html
Then there are the large prismatic LFP cells that range from 20AH up to 1000AH. These cells can be purchased in custom built packs with a BMS or they can be top balanced and installed as a DIY battery bank. Proper balancing and charging procedures need to be carefully followed with a DIY bank.
Here's a link to this type cell.
http://www.electriccarpartscompany.com/Prismatic-Lithium-Batteries_c_1.html
Rick
Sadly, with LFP, the basics of battery bank construction are lost.
Ask yourself this: If you were building a large capacity AGM bank for your RV, would you purchase hundreds of 2.5Ah Odyssey/Enersys Cyclon cells and tack weld them all together and slap them in a box? (as good as those are). NO.
At least battle born identifies the LFP chemistry. However, we have no idea what the quality of those internal cells are, nor are we assured that the quality won't change if they decide to go with different vendors. The consumer won't know. Essentially, you don't know what you are getting.
Do you buy lead acid this way not knowing who actually made your cells?
In the past, *NEW* cells like A123 were proudly identified as being the internal cells with certain large(ish) capacity batteries (along with Kokam and others), for those of us in the know to make a more informed decision.
STill, at some point we avoid the "magic box" concept not knowing what is actually inside, and potential problem points adding up from so many internal connection points. Hence the simplicity of large prismatics you can actually put your voltmeter across - on each and every cell as part of a preventative maintenance routine.
Yep, I have spoken with Carl several times and yes, he knows his stuff. So, 8 100AH cells in series is a 24 volt 100AH battery bank. Standard charge current is about 33 amps. The 3 panels with an MPPT controller should give you 21 to 26 amps depending on panel temp. It's a fairly small bank for a 3000 watt inverter, but you haven't stated the loads involved so might be ok. What's the brand and model number? Is this for RV?
Rick
Inverter brand is Power Tech on (Arizona company), This is the inverter.
Charge Controller is an EPPV Tracer 40a MPPT. This is the controller.
I hope I'm doing this right. I am less confident today.
2 parallel strings of 4 cells in series would give you a 12 volt 200AH bank.
Rick
The inverter link didn't work. I assure you that 16 100AH cells would be necessary to make a 12 volt 400AH bank, but I wouldn't recommend doing it that way. There must have been some miscommunication with Carl concerning the battery. They had 400AH cells up until a couple of months ago but not now. 220AH are the largest they have right now.
Rick
Also, the 40 amp controller is going to limit power production to 576 watts or about 2.5 KWH, and that's with a 5 hour solar day. Probably less than your loads and about half of what a 400AH bank will hold. I believe a 60 amp controller would be more appropriate.
Rick
Thanks, Rick. Looking into it, now!!!
The reason I asked about the inverter is the tare lose, the power that the inverter itself uses. It can be 500 watt hours or more per day with larger inverters and needs to be taken into account with the loads while planing a system.
Rick
I'm not sure about a rule. The tare lose is in watts, and usually listed in the inverter manual.
By the way, did you get the battery issue resolved with Carl?
Rick
There's a loss inherent in the efficiency of converting lower DC voltage to higher AC voltage, which depends on the inverter and the size of load. Peak efficiency seems to be about 85% for most decent PSW inverters, but it can be much lower with small loads on a large inverter.
There's also a loss caused by just having the inverter on and idle. Larger inverters tend to have larger idle losses. Some have a search mode to reduce this type of loss.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter