# ''ir'' In Batteries



## NCFRC (Aug 4, 2005)

Yes , another battery question.

I realize that matchers like to keep this to themselves and I havn't got one to reveal their tricks of the trade but does anyone know how their getting 
the IR down without killing runtime like deadshorting does ??

The question is about nimh cells in general .


Thanks for any feedback :thumbsup:


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## NCFRC (Aug 4, 2005)

someone must know :thumbsup: :thumbsup: :thumbsup: :thumbsup: 

Come on , I won't tell


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## NCFRC (Aug 4, 2005)

Everyone is pretty tight lipped


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## hankster (Jan 1, 1998)

You can lower the IR by zapping.


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## MIKE VALENTINE (Mar 12, 2002)

NCFRC, dead shorting the newer cells hasn't produced lower IR's in the few packs I have tried it with.


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## ToddFalkowski (Aug 31, 2006)

On EP's or IB's- I've found by deadshorting the average voltage goes up, the runtime goes down, and the IR doesn't change. 
.


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## NCFRC (Aug 4, 2005)

hankster said:


> You can lower the IR by zapping.


What do you recommend for a zapper ??

Not a maintainance one.


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## hankster (Jan 1, 1998)

I don't recommend any. From what I understand most matchers use custom built zappers.


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## NCFRC (Aug 4, 2005)

Thanks for the feedback and I did get some info on building a Zapper.

I'd rather not post it because THESE THINGS CAN KILL YOU !

It's been proven with these electric hybrid cars that you have to be very carefull as the DC voltage is so high its lethal .


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## ghuber (Mar 1, 2004)

You don't want to get shocked but a zapper... It probably won't kill you but it won't be a pleasant experience...


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## Mike Clark (Apr 28, 2007)

DC Current lacks the frequency need to disrupt heart functions, however burning your ass up is a real problem.

When ever current leads in a circuit lookout. It may not kill you but you will remember the experience!


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## ScottH (Nov 24, 2005)

Come to work with me, I can put you on some DC that will definately stop your heart.


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## burbs (Apr 21, 2002)

If the matcher did a proper job zapping, you wont need to do it again.. All the zapping does is weld the insides of the cell that would normally move while charging. Its basically a plate, then a spring type, and another plate. The zap welds this solid... This allows the pack to charge quicker and release the power quicker... Unless the weld breaks, a re zap is usless...

I just took apart and re zapped all of my 4200 packs.. I used a matcher type zapper, and did not get any gains from doing it..The cells cycled almost exactly the same as they did before the re zap.. this means all of the cells were properly zapped the first time..

I know my matcher personally, and can tell you there is no secret trick.. If you were told there was someone is pulling your leg..Matchers get low IR's because they see thousands of cells, and only sell or keep the best ones for there teams..


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## Mike Clark (Apr 28, 2007)

Hi Scott,
Yep elevators can be nasty little buggers from 250 to 500VDC. Some of the stuff I work with can be equally nasty, low voltage FVD's with a 860 VDC bus or medium voltage drive that will input 4160 volts AC and operate the transistors with a bus voltage at or above 8000VDC. AC stops a heart, DC to restart it. 

Battery Zapping
I thought the zapper would clean the individual battery plates through the high voltage influx. Which iturn would lend itself to more battery capacity because of more space available on the individual cleaned battery plates. The same is true if you form a battery or Capacitor.

Does lowering the internal resistance really allow for a better discharge. I thought the lower resistance in any cell would lengthen the time it would hold a charge.

Is there really enough current used with a Zapper to weld something inside the battery? What welds together? certainly not the plates. Or has battery technology changed that much?

Which voltage is increased? Peak, Average or discharge voltage?

Inquiring minds want to know? Where are the Zapper guys?


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