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Ideas for two systems -- 1 with 600ah LiFePO4 and 1 with 200ah AGM

Joined
Nov 12, 2019
Messages
26
Location
New Orleans burbs
In the past year or so, I acquired 2x 100ah AGM batteries as part of a Craigslist package that I bought ($400 for NIB 3x 100watt solar panels, Renogy PWM charge controller, MSW inverter, cables, wiring, and the two batteries). I'm not using the charge controller or MSW inverter. I have 1,200 watts with 600ah of LiFePO4 as my primary system but have a smaller 2nd system with the two 100ah AGM batteries. Right now, I have the main system on tiny home and the small system on my travel trailer as I repair/renovate/make road ready.

My plans are to put the main system on the TT once it is done and ready, then I'll technically plug the tiny home into the TT system. I'll put the small system on the tiny house so it will have some power when I'm away from basecamp (to run security system, etc.)

Do you all think this is the best plan or would I be able to use the smaller system also on the TT to give me even more power and then just plug the tiny house into the grid when I'm away from it. Yes, I have grid power as a backup but mainly live off of my off-grid solar systems. I also have a rental tiny house that needs grid power which is why it's also available to me if/when needed.

Thanks in advance.
 
Assuming you'll be spending more time in the travel trailer than at basecamp, it sounds like a reasonable plan to me

Don
 
It all depends on your usage. Measure it, ie you have to do a power-budget of how much you'll use each day.

Otherwise, you'll waste $$ throwing darts at the project.

Off the top of my head, my suggestion is to charge those agm's NOW, rather than let them sit around. Individually at first. If you don't have any AC, then get another panel at the very least, and use your spare charge controller. Don't let them sulfate.

Off the top of my head without any actual usage scenarios, I'd say keep the agm's as a backup / secondary system which will help provide more days-of-autonomy if your 600ah LFP bank won't cut it come wintertime.
 
Thanks for the replies. Wintertime is the easy part down here in S. Louisiana. I have a Buddy propane heater and also bought a diesel heater but never had a chance to get it going before winter was over. I may add more solar panels but I'm learning to live off my 600ah LiFePO4 and once I get to mostly using the TT, I can probably even run the small window A/C unit off of the batteries since I won't have the full-size 18cf fridge and 5cf chest freezer in the TT. I do have both of them on timers so they do not run 24/7 and I use a Govee remote temp sensor to monitor the temps of the fridge and freezer and have that down so my fridge temps stay between 36F and 42F. The freezer has to run less to keep everything frozen.
 
Nice idea on paper, but not so much in practice. Simply because most people don't properly charge and maintain lead in the first place. If they are that savvy, they'll opt for an all-lead solution, or better yet, and all-LFP solution, but not a hybrid.

The second factor is that most battery purchasers seek the cheapest batteries available, quite commonly 2nd-hand beaters, and frequently not at all designed for their intended application.

The hybrid solution is just a way to beat some cycles out of lead trash, and if one is into that, then I guess that's their choice. Ok.
 
I thought about it. This is the only web site that recommends this. My system is 48 Volts at 210 AH in batteries that are 6 months old. There are 8 six volt batteries in series. It is clear that I need more storage as I get 2 to 3 hours of float charging most days. The inverter shuts down around 10 PM because the batteries are down to about 60%.

One option is to buy another 8 batteries and hook them up 2p 8s with my existing batteries. This would cost about $900 for a single added sting.

A second option is to buy 16 280 AH lithium cells and a BMS. This option runs around $2200. I'm excited about playing with lithium.

Both options bring the storage from about 5 KWH to about 10 KWH. The hybrid option, if it works, will bring the total to about 15 KWH.

Do you have any thoughts?
 
I thought about it. This is the only web site that recommends this. My system is 48 Volts at 210 AH in batteries that are 6 months old. There are 8 six volt batteries in series. It is clear that I need more storage as I get 2 to 3 hours of float charging most days. The inverter shuts down around 10 PM because the batteries are down to about 60%.

One option is to buy another 8 batteries and hook them up 2p 8s with my existing batteries. This would cost about $900 for a single added sting.

A second option is to buy 16 280 AH lithium cells and a BMS. This option runs around $2200. I'm excited about playing with lithium.

Both options bring the storage from about 5 KWH to about 10 KWH. The hybrid option, if it works, will bring the total to about 15 KWH.

Do you have any thoughts? how about $3999 100ah 48v lithiu Lifepo4 battery?? i'm excited to join the lithium family! now i know there are 48v lithium on us warehouse. i am looking for some answer whether is worth!
 
价钱$ 3999的2x 100ah 48v锂电Lifepo4电池怎么样?我很高兴加入锂电大家庭!现在我知道我们的仓库中有48v锂。我正在寻找一些答案是否值得!
 
价钱$ 3999的2x 100ah 48v锂电Lifepo4电池怎么样?我很高兴加入锂电大家庭!现在我知道我们的仓库中有48v锂。我正在寻找一些答案是否值得!
how about $3999 100ah 48v lithiu Lifepo4 battery?? i'm excited to join the lithium family! now i know there are 48v lithium on us warehouse. i am looking for some answer whether is worth!
 
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