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Discussion Starter · #1 ·
Ok, I wanted to try some testing on my new packs. What is most important.....mah or Peak voltage? I am only going to lisst one pack but I did the test on another pack with the same results. Both packs had about 1200mah in them (4200mah WC). I discharged them at 10 amps on my ICE charger. When they shut off, I put them on the Tekin battery doctor until all the lights went out and left them on the tray for about another 10-15 minutes. I took them directly off the tray and charged them at 6 amps.

Yesterday
MAH Temp Peak V.
4503 127.4 6.183

Then, today, did the same on the discharge (there was about 1100mah left in the pack) but when I discharged and charged them, I turned my small fans on that I use to cool the batteries. The batteries didnt get over about 100 degrees this time but check out the Peak voltage...


Today
mah Peak V.
4441 6.314

So which way should I charge them? With the fan or without?

Thanks, Jeff
 

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don't take the bulbs down to nothing. you'll gain voltage but you'll kill the runtime. when the batts peak, they should be around 120-130 degrees. i'm not familiar with an ice charger but set your cut-off at .02 or 10mv.
 

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With todays batteries we have run time to throw away. You didn't say what class you are running but you CAN'T BEAT VOLTAGE no matter what class it is!

You may be discharging too deep to for the life of the pack though.
 

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Cooler peak temp results in ...

  • higher internal resistance (less torque)
  • higher peak voltage (no good, a killer pack will peak at lower voltage)
  • LESS performance
Look for 125F-130F at initial peak

High mAh charge doesn't mean anything ...

I recommend you don't let the cells "see" below 1V for too long ... couple of seconds fine but couple of minutes and runtime will be permanently gone.

The idea is not to come back to your pit and brag that you've got 999 seconds left of runtime in your pack ... the whole idea is to keep your battery pack properly matched. As soon as you take some runtime away form your cells you are "unmatching" your battery pack. Ex: Cell #1 loses 18 sec, Cell #2 loses 28 sec, Cell #3 loses 9 seconds, etc.

Steve.
TQ Cells
 

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Discussion Starter · #7 ·
Racin Steve said:
Cooler peak temp results in ...

  • higher internal resistance (less torque)
  • higher peak voltage (no good, a killer pack will peak at lower voltage)
  • LESS performance
Look for 125F-130F at initial peak

High mAh charge doesn't mean anything ...

I recommend you don't let the cells "see" below 1V for too long ... couple of seconds fine but couple of minutes and runtime will be permanently gone.

The idea is not to come back to your pit and brag that you've got 999 seconds left of runtime in your pack ... the whole idea is to keep your battery pack properly matched. As soon as you take some runtime away form your cells you are "unmatching" your battery pack. Ex: Cell #1 loses 18 sec, Cell #2 loses 28 sec, Cell #3 loses 9 seconds, etc.

Steve.
TQ Cells
Thanks Steve....thats more of what I was looking for. So the heat (to a point) is a good thing?
 

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I use an ICE charger for my 4-cell packs and I set the MAH to 4200. They usually peak around 4600-4900. I set the amp's at 6 and the peak sensitivity at .08 (I belive). With that, I have never had battery issues and they work great. I use a Novak Smart Tray for discharge with a .09 cut off.
 

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on my ice I set it at 6mv/c and I always get better voltage that way. Do you guys know how to set the peak delay on e Ice. It seems that on 5mv/c I get a lot of early peaking going on. Also does anyone charge using just a temp probe
 

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Discussion Starter · #11 ·
competionpark said:
on my ice i set it at 6mc/v i always get better voltage that way. do you guy know how to set the peak delay on that thing. also does anyone charge using just a temp probe
I dont peak my packs using the delay. I charge mine using the temp and the mv setting. 3mv and they are cutting off between 115 and 130.
 

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Like Steve mentioned, the charge #'s mean nothing.

Well, maybe not "nothing"........ increased peak voltage at the end of charge means the IR of the cells is UP, which means less power, and/or the cells are cold, or going bad/getting old. Low peak voltage and IR is a sign of strong cells..

You want the cells to have good numbers during discharge...... Like when the pack is in the car on the track.
 

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I meant actual not peak voltage. with 4200s I've had no problems with them on 5 or 6 but my 3800s would peak at 5.9 or 6.0v and had very little run time. it seems to me that outdoor charging hurt them bc it was 100 outside and they were partly exposed to direct sunlight and made them real hot.
 

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Competitionpark try useing the Step charge feature of the ICE charger the 4th step is the ONLY step thet the charger senses PEAK the other 3 stepps the peak detect is locked out just set the 3rd step MAH at when you want the peak sense to start eg 3800 mah or 4000 mah
 
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