Nicad cycling question
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Nicad cycling question
How do I determine battery health given the discharge time and discharge rate?
For example, 700 mah capacity pack discharged at 50 ma for 78 minutes.
I used to have a cheat sheet full of useful formulae and naturally, I lost the blasted thing.
Any help would be appreciated.
(I feel sooooooo dumb)
For example, 700 mah capacity pack discharged at 50 ma for 78 minutes.
I used to have a cheat sheet full of useful formulae and naturally, I lost the blasted thing.
Any help would be appreciated.
(I feel sooooooo dumb)
#2
RE: Nicad cycling question
G'day Mate,
In the old days, I used the time V discharge rate method, but for that to give you useful info, you need to know what 700Mah means, Mah is Milliamps per hour, so it means that the pack will, if it has 100% capacity, deliver 700Ma, in 1 hour, or 350Ma in 2 hours & so on.
As a general rule, I would charge at 1/10 capacity, in you case 70Ma, & discharge at 1/2 capacity, in your case 350Ma, that should give you 2 hours for discharge.
But these days, I use a discharger, that gives me a read out of the actual Milli Amps, that I get out of a pack, at the same rate every time, & it displays that reading in Milliamps, & cuts off the discharge, when the battery voltage drops to 1.1 volts per cell.
I can easily work out the "%" of capacity that I get from there.
Say it was an 1100Ma pack & I get 1012Ma out of the pack, then I know that is 92% capacity,
I will use the pack until I get about 80%, if it won't give me more than that, after a couple of cycles, I will throw it away.
That usually takes a few years.
In the old days, I used the time V discharge rate method, but for that to give you useful info, you need to know what 700Mah means, Mah is Milliamps per hour, so it means that the pack will, if it has 100% capacity, deliver 700Ma, in 1 hour, or 350Ma in 2 hours & so on.
As a general rule, I would charge at 1/10 capacity, in you case 70Ma, & discharge at 1/2 capacity, in your case 350Ma, that should give you 2 hours for discharge.
But these days, I use a discharger, that gives me a read out of the actual Milli Amps, that I get out of a pack, at the same rate every time, & it displays that reading in Milliamps, & cuts off the discharge, when the battery voltage drops to 1.1 volts per cell.
I can easily work out the "%" of capacity that I get from there.
Say it was an 1100Ma pack & I get 1012Ma out of the pack, then I know that is 92% capacity,
I will use the pack until I get about 80%, if it won't give me more than that, after a couple of cycles, I will throw it away.
That usually takes a few years.
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RE: Nicad cycling question
Read this: http://members.aol.com/davthacker/abattfaq.html
Or this: http://www.hangtimes.com/rcbattery_faq.html
Or this: http://www.rcbatteryclinic.com/
Or this: http://www.hangtimes.com/rcbattery_faq.html
Or this: http://www.rcbatteryclinic.com/
ORIGINAL: MJFinegan
How do I determine battery health given the discharge time and discharge rate?
For example, 700 mah capacity pack discharged at 50 ma for 78 minutes.
I used to have a cheat sheet full of useful formulae and naturally, I lost the blasted thing.
Any help would be appreciated.
(I feel sooooooo dumb)
How do I determine battery health given the discharge time and discharge rate?
For example, 700 mah capacity pack discharged at 50 ma for 78 minutes.
I used to have a cheat sheet full of useful formulae and naturally, I lost the blasted thing.
Any help would be appreciated.
(I feel sooooooo dumb)
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RE: Nicad cycling question
I use Hughesrc.com charger and cycler. It will do 4 bats at a time. On their website there is a chart that shows a 700ma fast charge at 700ma C/10 at 70 for 16hrs. trickle at 17 ma discharge at 140ma. their charger can be programed for your batteries and named. I use it in the shop to break in new ones and in my trailer to balance the batteries that i have fast charged. Bring up the program plug up the plane and go home. It will cycle X3 and charge back. By next sunday I'm ready to go. I do this every couple of months to all three of my planes. Dennis