Anyone use a capacitor BMS?

[polynoth]

I found several BMS boards for LiFEpo4 cells that instead of bleeding off cells with higher voltages, transfer voltage from them to lower cells, constantly. I have not been able to find anyone that uses these. It's larger, at just under 8 inches long, an inch or so thick and two inches wide, (approx conversions, 198x60x28 MM) and It draws 200 microamps until LV is triggered... I am strongly considering pairing this with some headways on my build...
http://evcomponents.com/60v-20s-lifepo4-50a-100a-capacitor-bms.html
they have them for other voltages, but I am probably going 60v.
Does anyone use these, or something similar?
I dont see too many glaring cons at this stage, but maybe someone can.

 

[john61ct]

please link to the BMS models you're talking about

also a good source for Headway if you have one

 

[jonyjoe303]

on the notes for the capacitor bms on your link (cost 119) it says it balances at 100ma. Thats just barely a little more then a regular bms can do. If the battery is severely out of balance it won't keep up with it if fast charging. It will work ok if you are slow charging.

"notes from 50A-100A Capacitor BMS for 60V 20S LiFePO4
Advanced capacitor balancing technique which is working at charging,discharging and static state all the time.It balances cells by transfering energy from higher cell to lower cell(by nominal 100mA). Save energy and reduce heat emission in balance process(compare with resistor bleeding bms)."

I seen 24s active balancers on ebay for about the same cost that can do 1 amp balancing. But they are only for balancing, you still need to supply your own bms. 1 amp balancing is better then 100ma. They got some that can balance at 3 amps but thats more cost, these also use 2 large capacitors to transfer energy. If I needed 24s to balance I would look at those. On my 4s I use the qnbbm balancers (100 dollars for 4s) balance at 6 amps but those are too expensive for 60 volts. On youtube you can see people who use some of these active balancers.

 

[amberwolf]

I have not been able to find anyone that uses these.

https://endless-sphere.com/forums/search.php?keywords=%22capacitive+bms%22&terms=all&author=&sc=1&sf=all&sr=posts&sk=t&sd=d&st=0&ch=300&t=0&submit=Search

https://endless-sphere.com/forums/search.php?keywords=%22charge+transfer%22+bms&terms=all&author=&sc=1&sf=all&sr=posts&sk=t&sd=d&st=0&ch=300&t=0&submit=Search


Some others show up in this search but there's lots of irrelevant stuff
https://endless-sphere.com/forums/search.php?keywords=capacitive+bms&terms=all&author=&sc=1&sf=all&sr=posts&sk=t&sd=d&st=0&ch=300&t=0&submit=Search