Dead Cell?
12-11-2005, 12:26 PM
#1
Senior Member
Thread Starter
My Feedback: (1)
Join Date: Aug 2004
Location: Springtown,
TX
Posts: 2,424
Dead Cell?
long story short:
Recently, I crashed an ultra stick. The plane was rebuilt, but the battery took a big hit in the crash--the shrink wrap was knocked off of it. However, it wasn't dented, and the connections were still all solid. So, I ran it through my triton about ten cycles--everytime it came back to 1100 mah, give or take. Seemed ok. I flew with it and it flew just fine, and took a charge from my field charger--this was about three or four weeks ago. Weather has been bad, and I was getting ready to go back out today, so I hooked it up to the quick field charger to top it off.
The charger went nuts. Would flash 80%, then back to 40%, then up to 80%, then stop flashing all together--like it wasn't charging anymore. I hooked the charger to another battery, and it charged ok, so the charger is fine. I checked the batter in question with my ESV, under 300 mA load. It read fully charged. I hooked the charger back up to it--same thing.
Needless to say, I'm trading the battery out in the plane right now--before I fly it. And, I'm starting the questionable battery back on the cycler again. However, maybe I don't know how to use the triton.
Here is my real question: When I use the cycler--any cycler, not just the triton--what do I look for if there is a dead cell? I thought that if I was getting full Ah rating on each cycle, then that meant the battery was fine. Is this true, or not?
Also, do you think I should just file the battery and get a new one? I'm definitely not flying with it again until I get it figured out. Right now I'm putting in a wimpy old 600 mAh battery I have laying around. I guess I'll just check it after each flight! I know the 600 mAh battery is good, it just won't last as long as the 1100 I pulled out of it :-(
OK, thanks for the input!
Recently, I crashed an ultra stick. The plane was rebuilt, but the battery took a big hit in the crash--the shrink wrap was knocked off of it. However, it wasn't dented, and the connections were still all solid. So, I ran it through my triton about ten cycles--everytime it came back to 1100 mah, give or take. Seemed ok. I flew with it and it flew just fine, and took a charge from my field charger--this was about three or four weeks ago. Weather has been bad, and I was getting ready to go back out today, so I hooked it up to the quick field charger to top it off.
The charger went nuts. Would flash 80%, then back to 40%, then up to 80%, then stop flashing all together--like it wasn't charging anymore. I hooked the charger to another battery, and it charged ok, so the charger is fine. I checked the batter in question with my ESV, under 300 mA load. It read fully charged. I hooked the charger back up to it--same thing.
Needless to say, I'm trading the battery out in the plane right now--before I fly it. And, I'm starting the questionable battery back on the cycler again. However, maybe I don't know how to use the triton.
Here is my real question: When I use the cycler--any cycler, not just the triton--what do I look for if there is a dead cell? I thought that if I was getting full Ah rating on each cycle, then that meant the battery was fine. Is this true, or not?
Also, do you think I should just file the battery and get a new one? I'm definitely not flying with it again until I get it figured out. Right now I'm putting in a wimpy old 600 mAh battery I have laying around. I guess I'll just check it after each flight! I know the 600 mAh battery is good, it just won't last as long as the 1100 I pulled out of it :-(
OK, thanks for the input!
12-11-2005, 01:13 PM
#2
Join Date: Dec 2001
Location: Upplands Vasby, SWEDEN
Posts: 7,801
RE: Dead Cell?
Hi!
Just check each cell with with a multimeter!
Put needles in each cell and measure the voltage...it should be at least 1,2V per cell under load(cell fully charged). Have some servos in work when you make the test, or put on another load. If any cell under 1,1V, just discard the battery.
I do not use anything but Nickel metallhydrid cells today (GP or Sanyo). Ni-cad is something of past!
And do slow charge once in a while..I personally never fast charge my batteries, except my lipos in my electric airplanes.
Regards!
Jan K
Sweden
Just check each cell with with a multimeter!
Put needles in each cell and measure the voltage...it should be at least 1,2V per cell under load(cell fully charged). Have some servos in work when you make the test, or put on another load. If any cell under 1,1V, just discard the battery.
I do not use anything but Nickel metallhydrid cells today (GP or Sanyo). Ni-cad is something of past!
And do slow charge once in a while..I personally never fast charge my batteries, except my lipos in my electric airplanes.
Regards!
Jan K
Sweden
12-13-2005, 12:46 PM
#3
Senior Member
Join Date: Nov 2005
Location: allenstown, NH
Posts: 107
RE: Dead Cell?
check the voltage of the packif under 4 volts chances are you have a shorted cell.have not used the triton but my ace or lr taylor will not discharge a pack with a bad cell,goes immediately into charge mode.i check packs for shorted or bad cells that way first if they start to discharge then i will charge and dischage them to see what the capacity left is .
12-14-2005, 01:54 PM
#4
My Feedback: (16)
Join Date: Dec 2001
Location: Shelby, OH
Posts: 37,565
RE: Dead Cell?
One bad cell ruins the whole pack.
A battery pack is only as good as it's weakest cell.
Enjoy,
Jim
A battery pack is only as good as it's weakest cell.
Enjoy,
Jim
