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I just built my first 12v 4s LiFePo4 prismatic pack, and it went smoothly, but...

Yurtdweller

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I just built my first 12v 4s LiFePo4 prismatic pack, and it went smoothly, but:p

The 16 280ah LF280Ks cells that I got from Amy Wan were very well matched. I am off-grid, and entirely 12v at the moment, so it made the most sense to build a 12v pack with bms, and bulk up the charge with my solar CC, and then separate the cells and parallel/charge them to TB. I chose the lowest capacity cells, even though they were all in the high 280s, and assembled my first pack. Well, after some cloudy days, the battery topped up today at 3.6vpc, and the cells appear to be in balance. The bms did a little balancing early on, but not too much today. Does this mean they are properly top balanced? Or should I hook them up to the power supply and goose them somehow? I could care less about squeezing them for juice. Happy to stay inside the curves.

TIA and for all the forum members. I travel most of the year in a yurt, and live in private campgrounds on jobsites for months at a time, and I'm off-grid about 10 months a year. I've been growing my system for over 6 years. My system has unique requirements, and LiFePo4 will be a game changer when it comes to loading up my whole home for travel:) Will, and this forum are the reason I feel confident to attempt this. Cheers!
 
You are good to go and they likely won't give you any troubles. You may want to drop the charging to a max of 3.5Vpc / 14.0V as you are just charging into the high curve above the working voltage and gain nothing but wear/tear on the batteries.
 
I just built my first 12v 4s LiFePo4 prismatic pack, and it went smoothly, but:p

The 16 280ah LF280Ks cells that I got from Amy Wan were very well matched. I am off-grid, and entirely 12v at the moment, so it made the most sense to build a 12v pack with bms, and bulk up the charge with my solar CC, and then separate the cells and parallel/charge them to TB. I chose the lowest capacity cells, even though they were all in the high 280s, and assembled my first pack. Well, after some cloudy days, the battery topped up today at 3.6vpc, and the cells appear to be in balance. The bms did a little balancing early on, but not too much today. Does this mean they are properly top balanced? Or should I hook them up to the power supply and goose them somehow? I could care less about squeezing them for juice. Happy to stay inside the curves.

TIA and for all the forum members. I travel most of the year in a yurt, and live in private campgrounds on jobsites for months at a time, and I'm off-grid about 10 months a year. I've been growing my system for over 6 years. My system has unique requirements, and LiFePo4 will be a game changer when it comes to loading up my whole home for travel:) Will, and this forum are the reason I feel confident to attempt this. Cheers!
I'd be interested to see some pictures of your "portable" yurt if you have some.
 
You are good to go and they likely won't give you any troubles. You may want to drop the charging to a max of 3.5Vpc / 14.0V as you are just charging into the high curve above the working voltage and gain nothing but wear/tear on the batteries.
Cool. Thanks. I will probably do that after I've had a chance to do a capacity test.
I'd be interested to see some pictures of your "portable" yurt if you have some.
It ain't real pretty, but it keeps me dry:) Btw, zoom on my sig icon:) Here's a picture during setup, and an interior shot with my dark tarp, and another with my old(deceased) clear pool cover.
 

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