4s4p LiFePO4 Build Log

ed209

New Member
Thank you for sharing all the details of your project. I'm thinking about buying the same batteries but like you've already said, finding a big enough tool box / container is a problem.
You're welcome -- it's also to keep me motivated between project time (day jobs are such a drag :))

The batteries are gorgeous but they aren't as easy to work with as prismatics, where the leads are on the same side. I'll have more details of my box in a few weeks as I start the fitment process.

If looking for containers: total length of the battery is about 320mm. 280mm + 20mm of leads on each side. And 60mm diameter of course.
 

ed209

New Member
Those breakers are something else I have been looking at some that I would like to connect between my inverter and MRBF fuse. Want it mainly for the compact size of having a disconnect.
They make battery disconnect switches that are pretty compact and enclosed. If you use it a lot that might be a more durable option. Search for "mini battery cutoff switch"
 

tim0shel

Solar Addict
They make battery disconnect switches that are pretty compact and enclosed. If you use it a lot that might be a more durable option. Search for "mini battery cutoff switch"
Yeah I have been doing some image searching and at the 300amp mark they do offer some decently sized. Still do not seem as small as some of those circuit breakers. But would feel better with an actual switch used.
 

ed209

New Member
Everyone: LiFePO4 batteries have a very flat voltage curve

Me: Yep, sounds good. My batteries are pretty close to full so I'll just top balance with this dinky charger instead of wasting time reassembling the pack.

6 days later.... finally starting to get near 3.5 volts.

Adding an open circuit voltage chart I found, and wish I had before I started!
 

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rs50pilot

New Member
Looking good, I was thinking of buying these or the 100ah packs that are made from their 32650s.
Any idea what one of these cells weigh? It's not listed on the site.
 
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Prizm

New Member
Looks good just got done building mine.
 

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Short_Shot

Photon Sorcerer
Why the hate on that breaker? I've got a 40a and 50a in my van.
Only replying to agree with others.

Those things are bad and shouldn't be trusted. Popping early is one thing but they also like to simply not work at all, or add a ton of resistance to the circuit and get hot.

I've had my share of them when I was a dumb kid doing car stereos. Installed a dozen of them before I started learning first hand about their issues.
 

Prizm

New Member
Awesome!

I like the way you did your bus bars, lots of flexibility.

I’m in the middle of moving so my project is on hold for a while :(
I used 1/8 by 1.25'' aluminum sanded real good with paste. Learned a lot from yours. thanks
 
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