View Full Version : limits on out of balance lipos?


GNS Racing
05-23-2009, 08:28 PM
hi
i just purchased my 1st lipo venom 4000mah 20c
bought a blinky balancer. and a low voltage cut off for my slash

followed instructions to the t
balancing checked good on new batt. charged at 4 amp with super brain
i think its the 989 any how does lipos charged good went to 8.4v then went into trickle mode left it on there for about 2 minutes then the amps started droping went downt to 2.4 amps on trickle shut it off slash run great about 15 to 20 min.
low volt cut off kicked in so went for recharge blinky says its out of balance
testing showed a .015vdc difference in cells (2cell batt)
both cell over 3.5 vdc one was like 3.77 and the other 3.62
i have had the balancer on for about 2 hrs and still not balanced.

should it take this long?, am i doing anything wrong? should i charge with blinky @.250 amp?
complete noob to lipo

thanks steve

lidebt2
05-23-2009, 09:07 PM
hi
i just purchased my 1st lipo venom 4000mah 20c
bought a blinky balancer. and a low voltage cut off for my slash

followed instructions to the t
balancing checked good on new batt. charged at 4 amp with super brain
i think its the 989 any how does lipos charged good went to 8.4v then went into trickle mode left it on there for about 2 minutes then the amps started droping went downt to 2.4 amps on trickle shut it off slash run great about 15 to 20 min.
low volt cut off kicked in so went for recharge blinky says its out of balance
testing showed a .015vdc difference in cells (2cell batt)
both cell over 3.5 vdc one was like 3.77 and the other 3.62
i have had the balancer on for about 2 hrs and still not balanced.

should it take this long?, am i doing anything wrong? should i charge with blinky @.250 amp?
complete noob to lipo

thanks steve

I'm not sure of your charger but that aren't the far out.

I would discharge your battery(without the "blinky" connected) and then charge with the "blinky" connected. When the charger reaches 0 amp the battery is fully charged.

Most of my batteries are about the same range.

OvalmanPA
05-23-2009, 09:21 PM
Yes always charge balance a lipo. Discharge balancing doesn't seem to work very well. Don't worry about discharging at this point because the imbalance of the cells will cause one to discharge below the recommended cutoff of 3v per cell. So in other words hook up your "blinky" and go back to charging.

GNS Racing
05-23-2009, 11:47 PM
Yes always charge balance a lipo. Discharge balancing doesn't seem to work very well. Don't worry about discharging at this point because the imbalance of the cells will cause one to discharge below the recommended cutoff of 3v per cell. So in other words hook up your "blinky" and go back to charging.

thanks that worked
i blinky charged @ .200 of a amp and both lights came on @ .08 of a volt differance between the 2 cells

before i did that i tried discharging by running the slash untill the low volt cutoff kicked in. then checked the voltage 1 cell was @3.17vdc and the other was @ 2.90vdc that was emediatly (sorry spelling bad) when the cut off kicked in. by time i was back in my shop it was @3.0 VOLTS

hope i didnt hurt the battery so far seems ok

thank again
steve

herman2
05-25-2009, 10:49 AM
When charging my Lipos 2 at a time while balancing them. What amperage should I charge? The battery's are 5000mh.

GNS Racing
05-25-2009, 06:53 PM
When charging my Lipos 2 at a time while balancing them. What amperage should I charge? The battery's are 5000mh.

not sure on that im new to lipos,
but the instructions i got with mine said NEVER charge lipos in series

ive charged mine now at 2 amp 3 amp and 4 amp instructions said u could fast charge at 1c with means if you had a 4000Mah batt u can charge at 4 amps 5000Mah at 5 amps, but was told by guys at the track 2 amp is the safest and best for the battery

i found the best performance so far was at 3 amps on my 4000Mah took about 1 hr and the battery stayed cool this was from 6.2 volts to 8.4

GNS Racing
05-25-2009, 06:57 PM
not sure on that im new to lipos,
but the instructions i got with mine said NEVER charge lipos in series

ive charged mine now at 2 amp 3 amp and 4 amp instructions said u could fast charge at 1c with means if you had a 4000Mah batt u can charge at 4 amps 5000Mah at 5 amps, but was told by guys at the track 2 amp is the safest and best for the battery

i found the best performance so far was at 3 amps on my 4000Mah took about 1 hr and the battery stayed cool this was from 6.2 volts to 8.4

dont take my input without checking with a expreanced person like i said i have only hade this lipo less than a week, raced stock slash this weekend and worked great.

herman2
05-26-2009, 09:11 AM
ok thanks!...I love my new Lipos..they sure make a difference thats for sure!..I am charging at 3 amps cause thats what the guy said who I bought it off of but was wondering what others were doing. I put my battery's in the freezer for 5 minutes to cool them down after charging!

ta_man
05-26-2009, 09:19 AM
ok thanks!...I love my new Lipos..they sure make a difference thats for sure!..I am charging at 3 amps cause thats what the guy said who I bought it off of but was wondering what others were doing. I put my battery's in the freezer for 5 minutes to cool them down after charging!
That's about the worst possible thing you could have thought of to do. Other than dousing them with gasoline and lighting them.

kevinm
05-26-2009, 06:46 PM
... I put my battery's in the freezer for 5 minutes to cool them down after charging!
Your LiPos should NOT be hot after charging! If they are, you're not charging correctly (wrong charger or wrong charge mode).

SLASH4
06-03-2009, 10:49 AM
i charge them at 6amps never been hot and never get hot running either ran in 1/8 scale buggy

nutz4rc
06-03-2009, 05:00 PM
Heat in a lipo = trouble. As previous post said. Something is wrong. Does the charger do the CC CV charging that is required of a lipo charger? What type of charger? I always charge at 1C' so for my 4800 MAH I charge at 4.8 Amps, 5400 at 5.4, and 1300 at 1.3. Never had any heat in lipo. Never had a hot lipo after racing either.

ovalrunner302
06-11-2009, 05:35 PM
I'm going to have to check my paper work at home, but I remember seeing on one of
my new lipo battery warning sheets that there seem to be issues with your particular charger and some of the other MRC chargers. I think it was an SMC warning sheet.
Maybe get a hold of Danny @ SMC and ask him .

rustytraxx
06-16-2009, 03:39 PM
I charge my zippy 2s 4000 lipos at 4a and they never get above roomtemp.+1 heat on a lipo = http://i653.photobucket.com/albums/uu258/renderedspeechless/Decorated%20images/nuclear-bomb-explosion.jpg

CustomWire
07-02-2009, 10:43 PM
old post i know but my lil 2cents lol

GNS racing .. said this
does lipos charged good went to 8.4v then went into trickle mode left it on there
"TRICKLE" ???
never heard such a thing on lipos ????? you charge them to full then charger stops charging ... sounds with that trickle thing u had wrong setting .. like kevinm said

the onxy 230 charger is a nice all around one for the money and a lot of guys where i race use them as i do .. yes its made by duratrax but this they got right lol will its labeled duratrax anyways lol ...

HOT as said before is bad .. i run 3 diff lipos

SMC 3200 < charged at 6amps charged 3 times a nite in 2 hours at the 6amps 4 months old

duratrax 3700 < charged at 6amps uses sometimes not a lot 6 months old

checkpoint 5400 < charged at 6amps used sometimes beater pack as the duratrax is and 5 months old

double ur milleamp is ur max charge rate i been told so 3200 is 6.4 amps



get yourself a good charger and maybe go up half amp each charge and keep close eye on the pack .. as said before by one person .. when the amps show droppin on the charger thats givin you idea how long is left amps go down on charger to below 1amp its close to charged were is old Sub C's the amps stay at say 5 amps never go down on charging of pack ..

NEVER NEVER DISCHARGE LIPOS like a Sub C NEVER if u drop below 6volts on 2s packs i think it is toss it in trash some get lucky .. it may take one hit like that but more then that iam 87% sure its trashed and you dont have to discharge LIPOS anyways liek i read ..

as for balncing .. i havent done my smc pack in 2 months i dont charge balnce for long time .. i check it on a checkpoint one i dont have the blink and i know the checkpoint is .05 or .5 volts between it goes in balnc mode .. there picky ... check it once a week depending on useage and go from there ...

hope this gives u ideas .. but rememeber what works for one doesnt always work for others ..