Peak charging NiMH packs: do you or don't you? General consensus...
07-17-2006, 01:33 PM
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RE: Peak charging NiMH packs: do you or don't you? General consensus...
The electrical engineer in me is impressed,
The chemical engineer in me is astonded,
But the RC pilot in me still wants to kmow,
Can I peak detect charge NiMH packs?
Answer in 25 words or less ,if possible.
The chemical engineer in me is astonded,
But the RC pilot in me still wants to kmow,
Can I peak detect charge NiMH packs?
Answer in 25 words or less ,if possible.
07-17-2006, 03:32 PM
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RE: Peak charging NiMH packs: do you or don't you? General consensus...
Yes.
A Ni-MH has a much lower (than Ni-Cad) but still detectable voltage falloff at the peak. You must charge at a 1C or higher rate for a good charger to detect the peak.
A Ni-MH has a much lower (than Ni-Cad) but still detectable voltage falloff at the peak. You must charge at a 1C or higher rate for a good charger to detect the peak.
07-17-2006, 08:14 PM
#29
RE: Peak charging NiMH packs: do you or don't you? General consensus...
I peak charge my NiMH batteries (cells and packs) at C/5. Not a problem but the delta peak is much smaller than NiCd. I use a Miniron Mobil but there are a few things that can be done to improve the peak detection: 1) Use shorter and thicker charging cords to minimize the cord resistance; 2) Use a DC power source for the charger. I found through experimentation that when using an AC power source, the peak detection is not good probably due to AC noise affecting the peak detection circuit performance; 3) A good formation charge on the NiMH battery improves the delta peak. I find that the peak detection improves with use too; 4) When the battery temperature is too high, say above 45-50C, the peak detection deteriorates. Prolonged exposure to this temperature also deteriorates the battery life. I occasionally monitor the battery temp with a Raytek thermometer to check if my setup is correct; 5) The peak detection sensitivity of the charger needs to be optimized. This can be adjusted in some chargers, while some chargers like the Miniron or Alpha4 use proprietary circuitry. Hope this helps
07-17-2006, 09:32 PM
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RE: Peak charging NiMH packs: do you or don't you? General consensus...
ORIGINAL: kangarooster
But the RC pilot in me still wants to kmow,
Answer in 25 words or less ,if possible.
But the RC pilot in me still wants to kmow,
Answer in 25 words or less ,if possible.
Is kmow a special type of RC flying?
I have never heard of it.
07-17-2006, 11:42 PM
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RE: Peak charging NiMH packs: do you or don't you? General consensus...
One says that to charge 1C is necessary and another says that to use short fat leads is necessary to detect peak, but I detect peak all the time at c/10 and very long skinny leads.
This is very funny, but good thread. I tried to understand all that other stuff.
Peak chargeing nickle batts is A-ok.
This is very funny, but good thread. I tried to understand all that other stuff.
Peak chargeing nickle batts is A-ok.
