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Old 09-30-2003, 10:07 PM   #16
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Dead shorting may provide a TINY TINY increase in voltage output initially... but is in no way worth the extra wear and tear put on the cells... Peaking the pack, running it cool, then discharging down to 1v or .9v per cell, is PLENTY... and will give 99.999% the performace as dead shorting...

its not worth it.
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Old 09-30-2003, 10:11 PM   #17
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what the heck is r/c car??? ( said in your best redneck voice)

'OL BUZZARD FARMING (lol)

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Old 09-30-2003, 10:20 PM   #18
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Amen.
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Old 10-01-2003, 01:27 AM   #19
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ok heres an upadate on the batteries after race day
They where protty punchy out of corners but not as much top speed as normal ( that was with all the batteries
)
any 1 know why that would be
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Old 10-01-2003, 09:47 AM   #20
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Quote:
Originally posted by holycow
Dead shorting may provide a TINY TINY increase in voltage output initially... but is in no way worth the extra wear and tear put on the cells... Peaking the pack, running it cool, then discharging down to 1v or .9v per cell, is PLENTY... and will give 99.999% the performace as dead shorting...

its not worth it.
Seconded. Especially with NiMH cells, shorting them out does all sorts of Very Bad Things to the cell's chemicals. Cells that have been shorted may have better specs for a little while, but to me it's not worth the undeniable decrease in pack life. Shorting your cells WILL kill them. Maybe not today, but the damage done to the cells doesn't reverse itself.

-dave
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Old 10-01-2003, 09:55 AM   #21
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Quote:
Originally posted by acid_rain182

any 1 know why that would be
Because you damaged them.

When you short out a cell, the instantaneous, insanely high, amp draw causes the normally stable chemicals in the cell to become...less stable. The chemical reaction that causes batteries to work gets thrown all out of whack from the high rate of speed it's asked to perform at. Hydrogen gets pushed out of the molecules into bubbles that form inside the cells, preventing the reaction from happening at an efficient rate in the future. If the pressue form those bubbles gets to great, your cells will outgas some of it. Maybe not enough for you to notice goo at the end of your cells, but even with just the internal bubbles, your packs will have less voltage and less runtime because the chemistry no longer has access to some of it's hydrogen. It may seem to have more 'punch', but I'd be willing to bet if you threw those cells on a TurboMatcher for a few cycles, you'd find out that you'd hurt them.

-dave
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Old 10-01-2003, 11:45 AM   #22
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Quote:
Originally posted by lonestar1127
iszit impt to discharge at 30 mAh??? wat if i discharge it only at 20 mAh?
i think you mean amps cuz' mah is milliamps. anyway, 30 is better, and the numbers most people talk about (in regards to voltage) are those discharged off of 30 amps. 20 amp discharge # are higher in reading, but not in punch.

as for deadshorting, i've had only good luck w/ nicads. i'm sure the smc guys know what they're doing, but all my nimhs that i've dead shorted never really worked well for me after that.
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