Most reacted posts

Thanks! I was really interested in individual fusing of the packs as a last resort. In the event there is an internal cell short on a pack that does not trip the cell CID, AND the BMS malfunctions and does not catch it, there is a 10A fuse to prevent giant inrush of current into the pack. For...

Yup there are currently 19 packs in parallel (adding some more probably), each with a BMS. 6x 4p packs and 13x 5p packs. 6x4+13x5=89, so equivalent to having 89 cells in parallel. I'm lucky to have a source of packs through my work; I saved them the cost of paying someone to haul away to...

I'd agree with fusing each individual battery pack for max safety. Looks like I built something very similar as the OP -- I used automotive fuse blocks with fuses rated to 58V to tie it all together. Check out details in this post...

Yeah give this a try -- Bluetti should have a UPS feature. To use more solar, try having the Bluetti only hooked up to grid power from dusk-dawn (with simple wall timer). Then it will capture all the solar it can and also cover more than the 4hrs of higher electricity rates. 1152Wh battery...

I think if you only hook up the power station to the grid during the night (or even just a few hours in early evening) to make sure it's filled up, it will use the solar through the day to try and stay topped off. Just a Bluetti power station like you have and a standard dumb wall timer.

I hate to see this left out here dangling. I was googling around for 7S Li-ion charge controller settings and ended up here. I just built my own battery too! OP above clearly has a 7S Li-ion NMC battery, probably from recovered 18650's (average of 2250mAh each). Max safe charge voltage would be...

Wanted to comment that I also found the Optifuse APR58-UL (standard blade fuse ATO/ATC form factor) at Digikey and used them as the individual fusing for paralleling the packs in my DIY powerwall. I was also trying to find a good solution for low-current distribution/collection for my 48V...

The people on the (rude) Facebook forums will scream that dremel/sanding will allow the metal to corrode. No one there has ever shown any proof of that though. Anyone here have actual insights or data?

Yes that is a good point, and in the case of the OP, I suspect the battery reached the boost voltage (29V per the post) then went into float mode at 27.4V. Because Lithium (LFP and NMC) do not have voltage drop quickly when leaving "boost" mode like lead acid does, the charge controller was just...

Hey everyone, I wanted to share what I built this past year, a little different than many I've seen here. Big thanks for everyone's informational posts and YouTube videos (especially Will) I learned so much from. I had a bunch of 13s ebike packs with 18650 cells. I decided that since they were...

I would double-check that all of the packs are a compatible voltage. 60V is the max or nominal voltage? Or? A 14s lithium-ion NMC, for example, is nominally 52V and max 58.8V. With many in parallel, assuming same number of series strings in each, I think you just need to adjust the charging...

I contacted Blue Sea systems with the same question, and they confirmed for me that the voltage rating of 32V listed for the fuse block is just a limitation of fuse, not the actual block. My solution was to go to Digikey and find ATO/ATC form factor fuses rated to 58V -- they exist! Optifuse...