I don't know if everything you're after is there, but right at the top of this forum is this sticky:nutspecial said:
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=26621
Does that help?
How I killed a lipo cell <update- almost>
- Thread starter nutnspecial
- Start date
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=26621
Does that help?
nutnspecial
10 MW
Sure is thanks AW!
This section is most helpful if considering lipo http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=19956
I've missed any particular threads on bms'ing lipo, but would look or ask if it interested me.
My point is these folks should link something in the spirit of friendly helpfullness rather than come to argue and condemn. Gets old.
-'I've gOtta MONnster in my PArasol" Lol. That's what lipo is- kinda
This section is most helpful if considering lipo http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=19956
I've missed any particular threads on bms'ing lipo, but would look or ask if it interested me.
My point is these folks should link something in the spirit of friendly helpfullness rather than come to argue and condemn. Gets old.
-'I've gOtta MONnster in my PArasol" Lol. That's what lipo is- kinda
nutnspecial
10 MW
After several cycles the cell that was sub-2volts from unbalanced overdischarge is acting fine.
Although theoretically there always has to be a 'weak' link in the chain, this cell has certainly been very unmatched from the start, and it still shows.
If I sag the pack below 70volts (3.5v average) it just plummets, while the other 19cells are fine.
It's too much to ask of the cells to sag lower than a safe resting discharge voltage without weak links showing themselves and getting worse.
Too bad my 5.8ah pack sags 4v on 66a draw, it means I can't use all the capacity without limiting draw or beating up the weakest link in the series.
I wonder how the higher (50c 70c) lipos do in a similar setup? Do they still sag as bad with the same ration of ah vs draw?
Although theoretically there always has to be a 'weak' link in the chain, this cell has certainly been very unmatched from the start, and it still shows.
If I sag the pack below 70volts (3.5v average) it just plummets, while the other 19cells are fine.
It's too much to ask of the cells to sag lower than a safe resting discharge voltage without weak links showing themselves and getting worse.
Too bad my 5.8ah pack sags 4v on 66a draw, it means I can't use all the capacity without limiting draw or beating up the weakest link in the series.
I wonder how the higher (50c 70c) lipos do in a similar setup? Do they still sag as bad with the same ration of ah vs draw?
dnmun
1 PW
if you sagged a 20S pack to 70V then that cell is now dead. it woulda dropped below .2V under load and all of the electrode interfaces are now cooked.
