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Old 10-14-2005, 10:59 PM   #1
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Default Ni Mah vs. Ni Cad

ok i was wondering whats the difference for Ni Mah batterys and Ni Cad Batterys???

please help!
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Old 10-15-2005, 12:58 AM   #2
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Thats a pretty wide open question. The very short answer is, NiCd batteries are older technolodgy, NiMH are newer and are better in pretty much every way. They don't have the bad memory problem like the NiCd's do.

NiMh cells have come a really long way over the last few years too. They keep getting bigger and better.
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Old 10-15-2005, 11:49 AM   #3
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oh i see so how do you guys charge your batterys if you had a 3000 nimah battery
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Old 10-20-2005, 02:38 PM   #4
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you would have to use a charger designed for nimh or nimh and nicad batteries. your best bet would be to get a peak charger (a charger that has built in circuitry that charges a battery to peak voltage and stops charging at that point) the duratrax chargers are good and affordable. among others of course...
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Old 10-20-2005, 03:57 PM   #5
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i have the promax activator it saids it is a peak charger...does that work

thanks
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Old 10-20-2005, 07:16 PM   #6
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hi. seen people use nicds and have been just as fast....

i was wondering if nicad 2500's are equivalent of Nimh 3300's?

or put it another way...

are nicd 2500's better than nimh 2500's ?


thx
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Old 10-20-2005, 07:17 PM   #7
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Quote:
Originally Posted by qwerty
hi. seen people use nicds and have been just as fast....

i was wondering if nicad 2500's are equivalent of Nimh 3300's?

or put it another way...

are nicd 2500's better than nimh 2500's ?


thx

mah numbers should be about the same. and why is this thread still open? nobody uses them anymore.
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Old 10-21-2005, 03:18 PM   #8
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the nimh 2400's would be better because while they may have the same mah, the nimh cells will have higher voltage and wont suffer from cell memory.
also, i correct me if i'm wrong, but i think nimh cells have lower internal resistance, which translates into stronger acceleration. the most ive seen nicd cells have is 2400 mah, but theres nimh cells with 3800 mah now.
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Old 10-21-2005, 03:37 PM   #9
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If charging NiCads... what should the peak detect be set for???
the same 3 millivolts per cell as NiMh or higher ??

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Old 10-22-2005, 12:49 AM   #10
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Quote:
Originally Posted by Jack2
Thats a pretty wide open question. The very short answer is, NiCd batteries are older technolodgy, NiMH are newer and are better in pretty much every way. They don't have the bad memory problem like the NiCd's do.

NiMh cells have come a really long way over the last few years too. They keep getting bigger and better.
The "Memory" problem with Nicads is basically a myth. The idea of the memory problem arose from the use of Nicad batteries on board sattelites that charged via solar panels. During certain parts of their obits the batts would only receive say 80% charge, then discharge to 20% capacity, and so forth for a certain period of time. When their orbits were slightly different, the batts wouldn't charge past 80%.

Using NiCad's for RC, the memory situation never would really come into play for the simple fact that the batts were basically used up, as in they were charge so heavily and discharged so heavily that thier lifespan was so shortened by that abuse that they never had a significant amount of time to develop a memory.

However, NiMh do not seem to exhibit this trait anyway, if it was ever a situation with RC.

To answer the other question, is a Nimh 3300 better than a NiCad 2400, the answer is simply YES!!! Their voltage output is FAR beyond that of any nicad ever in use for the RC application its not even funny!!!

And now with the introduction of the Intellect IB3800 cell, they are seeing voltageages of 1.2 volts average on a 35 amp discharge. A Nicad 2400 (sanyo for instance) at a 35 amp discharge would be something like 1.12 volts. For a whole pack thats .36 volts difference. That is very substantial. The average 3300 (GP) produces better that 1.17 (at 30 amps), which is still .35 volts per pack (6 cell) more than their 2400 nicad counter part. *Note the 2400's in question were probably matched at 30 amps to get somewhere around 1.16 volts per cell, and and IB3800 at 30 amps could be as high as 1.21- still about a third volt better per pack.

In short, the Nimh technology is far better for capacity and voltage than Nicad.
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