View Full Version : PLEASE HELP WITH LIPO CHARGE.
hi,i have a bc6 charger,my lipo's are zippy lipo 2200mah 3cell 20/30c and are brand new.the problem is they are taking a long time to charge.i charge at 2.2a 3 cell,well i stopped the chargeing at 90mins,it had 0.1a left to go in,and the cell voltage of each cell was-C1 4.19-C2 4.19-C3 4.20.so am i doing some thing wrong here? my other lipo's are done in about 1 hour.please help.
thanks.
RC Accessory
10-28-2008, 05:36 AM
hi,i have a bc6 charger,my lipo's are zippy lipo 2200mah 3cell 20/30c and are brand new.the problem is they are taking a long time to charge.i charge at 2.2a 3 cell,well i stopped the chargeing at 90mins,it had 0.1a left to go in,and the cell voltage of each cell was-C1 4.19-C2 4.19-C3 4.20.so am i doing some thing wrong here? my other lipo's are done in about 1 hour.please help.
thanks.
Charge the pack at a lower rate for several cycles to see if this issue goes away.
hi,thank you for getting back to me.are you saying try charging at say 2.1a or even 2.0a?
thanks.
RC Accessory
10-28-2008, 01:10 PM
1 amp
JEB123
10-28-2008, 01:10 PM
What is the continuous/burst rates of the other LiPos, are they 20/30 also? Maybe that's why. I'm running 15C's and they take about an hour @ 1C.
1 amp
hi,sorry to be a bit thick here,but im not that great with my charger and lipo's,ive got a lot to learn! i always thought if a lipo is 2200mah then i charge at 2.2a,so why can i go below 2.2a? is it safe? will it take longer to charge? what would happen if i charge over 2.2a?
sorry for all the questions!
thanks.
RC Accessory
10-29-2008, 08:05 AM
hi,sorry to be a bit thick here,but im not that great with my charger and lipo's,ive got a lot to learn! i always thought if a lipo is 2200mah then i charge at 2.2a,so why can i go below 2.2a? is it safe? will it take longer to charge? what would happen if i charge over 2.2a?
sorry for all the questions!
thanks.
What you describe is 1C, C being capacity. You can always charge at a higher or lower rate depending on the battery manufacturer spec's. Low cost, cheap cells should charged at 1C or less as they are not matched for impedance.
1 Amp charge rate is less than .5C.
JEB123
10-29-2008, 01:11 PM
What you describe is 1C, C being capacity. You can always charge at a higher or lower rate depending on the battery manufacturer spec's. Low cost, cheap cells should charged at 1C or less as they are not matched for impedance.
1 Amp charge rate is less than .5C.
Impedance? How's that? Batteries do have an Z due to their capacitive nature, but I've never heard of charging with AC. Do they apply a signal and use Z matching to measure/match capacity or something? Please explain what you mean.
JEB123
10-29-2008, 02:11 PM
[quote=RC Accessory;934806]What you describe is 1C, C being capacity. You can always charge at a higher or lower rate depending on the battery manufacturer spec's. Low cost, cheap cells should charged at 1C or less as they are not matched for impedance.
OOops!
What you describe is 1C, C being capacity. You can always charge at a higher or lower rate depending on the battery manufacturer spec's. Low cost, cheap cells should charged at 1C or less as they are not matched for impedance.
1 Amp charge rate is less than .5C.
hi,im not getting it! sorry.how did you get 1c? my lipo is 11.1v 2200mah.what is the lowest i can charge my lipo at then? how long should i be chargeing for? should i just charge at 2.2a? as i am typing now i am chargeing a lipo 11.1v 2200mah at 2.0a and it has been chargeing for an hour and not stopped yet!! should i just stop it now?
thanks.
RC Accessory
10-29-2008, 03:39 PM
hi,im not getting it! sorry.how did you get 1c? my lipo is 11.1v 2200mah.what is the lowest i can charge my lipo at then? how long should i be chargeing for? should i just charge at 2.2a? as i am typing now i am chargeing a lipo 11.1v 2200mah at 2.0a and it has been chargeing for an hour and not stopped yet!! should i just stop it now?
thanks.
Charge the pack at 1 amp as I said earlier. This could take more than 2 hours to charge the pack.If there is an imbalance in your cells this will help balance the pack better.
Hi,so is 1amp 1c? is that the lowest i can charge then?
thanks for the help.
RC Accessory
11-01-2008, 06:03 PM
Hi,so is 1amp 1c? is that the lowest i can charge then?
thanks for the help.
1 amp would be 1C if the pack is a 1000 mah or 1 amp hour pack. C is the Capacity of the battery. If the battery is a 2000 mah pack, then 1C would be 2 amps. If the pack was 4800 mah, 1C would 4.8 amps.
100 mah or .1 amp is the lowest you can charge. Charge the pack at 1 amp.
JEB123
11-02-2008, 01:43 AM
Impedance? How's that? Batteries do have an Z due to their capacitive nature, but I've never heard of charging with AC. Do they apply a signal and use Z matching to measure/match capacity or something? Please explain what you mean.
RC Accessory (Evan), are you ignoring this question? ;)
RC Accessory
11-02-2008, 04:52 AM
After rereading m answer I used the impedance instead of resistance. My bad.
JEB123
11-02-2008, 04:01 PM
After rereading m answer I used the impedance instead of resistance. My bad.
Thanks man, you scared me. I suddenly pictured: Back to school! Oh no! They've changed electronics theory! :lol:
Actually, batteries are often rated by impedance. A varying DC voltage is affected by capacitive reactance just like a varying voltage that changes polarity (AC).
I have a battery impedance meter that tests at 1000 Hz, but the polarity never changes (imagine AC with a DC offset). It takes about 10 seconds to tell if a battery is going bad if there is a baseline (or a similar battery to compare with), and reads directly in milliohms.
JEB123
11-02-2008, 10:00 PM
Actually, batteries are often rated by impedance. A varying DC voltage is affected by capacitive reactance just like a varying voltage that changes polarity (AC).
I have a battery impedance meter that tests at 1000 Hz, but the polarity never changes (imagine AC with a DC offset). It takes about 10 seconds to tell if a battery is going bad if there is a baseline (or a similar battery to compare with), and reads directly in milliohms.
That was my initial thought, although I've never worked in battery testing, it makes sense because as you noted, a battery has a Xc. Thanks for your input Wyn.
Hey Evan, you were on the right track, you DID read that somewhere! Back to school! :P