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Old 05-05-2004, 05:14 AM   #1
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Default Internal resistance

Hi everyone,

I'm not really sure about what all the numbers mean on matched batteries, I know discharge time and volts, all the obvious ones but what does Internal resistants mean and is it important, and what do some of the other numbers mean but most importantly IR.

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Old 05-05-2004, 05:15 AM   #2
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Default Re: Internal resistance

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Originally posted by The_Gaz
Hi everyone,

I'm not really sure about what all the numbers mean on matched batteries, I know discharge time and volts, all the obvious ones but what does Internal resistants mean and is it important, and what do some of the other numbers mean but most importantly IR.

Gaz
I heard the lower the number is, The more punch The pack will have.
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Old 05-05-2004, 05:36 AM   #3
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Default Internal resistance

yeah I was told that internal resistance is nearly as important as discharge time, can anyone clarify
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Old 05-05-2004, 05:41 AM   #4
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RUNTIME>>> THE HIGHER THE NUMBER THE LONGER WILL LAST YOU PACK

AVERAGE VOLTS>>> THE HIGHER THE NUMBER, MORE RPMs

INTERNAL RESISTANCE>>> THE HIGHER THE NUMBER IS, MORE ACCELERATION....
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Old 05-05-2004, 05:41 AM   #5
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please keep in mind when buying matched packs that a pack charged at 5 amps is much different then packs charged at 6 amps when cycling for numbers...a pack with 5 amps for example 1.170 would be comparable to a 6 amp 1.174

Resistance makes a difference especially in stock racing...the lower it is the easier it is for the energy to come out of the cell since the insides have less crystaline structure= more punch
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Old 05-05-2004, 05:45 AM   #6
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Quote:
INTERNAL RESISTANCE>>> THE HIGHER THE NUMBER IS, MORE ACCELERATION....
?? surely the lower the internal resistance, the better the pack will be, ie more efficient etc.
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Old 05-05-2004, 05:49 AM   #7
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Default IR

So if a battery had a IR of say 28 - 32 it would be a poor battery in the terms of punch, as opposed to a say, 13 - 16 IR battery
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Old 05-05-2004, 06:06 AM   #8
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yes
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Old 05-05-2004, 06:11 AM   #9
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I am seeing two types of numbers for resistance, one in the double digit range from reputable matchers and others in the single digit range like this ex - 2.7 versus 17

Is there difference ways to rate resistance, if so, how do you compare the two?
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Old 05-05-2004, 06:15 AM   #10
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each individual cell is in series with the next- each cell forms part of the current path, so think of it as a resistance. the lower the internal resistance, the less impedance the cell places on the current flow through it. less impedance= more current= more punch.

or something like that.

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Old 05-05-2004, 06:55 AM   #11
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Quote:
Originally posted by Cain
I am seeing two types of numbers for resistance, one in the double digit range from reputable matchers and others in the single digit range like this ex - 2.7 versus 17

Is there difference ways to rate resistance, if so, how do you compare the two?
Those are two ways that they are measured. Most companys are going to the 2.7 way. I'm not sure how to compare them but with both ways, the LOWER the number the better. It's like bushings vs bearings. Less resistsnce the faster you will go.

You can take a battery with 1.17.5, ir 3.2 vs 1.16.9, ir 2.2 and the 1.16 battery will be faster cause of the less resistance.

Last edited by Chill Will; 05-05-2004 at 07:01 AM.
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Old 05-05-2004, 07:25 AM   #12
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Not exactly - a low voltage cell is a low voltage cell, low resistance or not.

The voltage the cell gives under load is quite closely linked to its IR - cells with a lower IR will usually have higher voltage under discharge (comparing like-with-like i.e. GP and GP).
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Old 05-05-2004, 09:49 AM   #13
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Quote:
Originally posted by SalvadoriRacing
RUNTIME>>> THE HIGHER THE NUMBER THE LONGER WILL LAST YOU PACK

AVERAGE VOLTS>>> THE HIGHER THE NUMBER, MORE RPMs

INTERNAL RESISTANCE>>> THE HIGHER THE NUMBER IS, MORE ACCELERATION....




r/c anonymous,pheyhoe,cain,ringo,chill will.

Nice explaining bor!!!.



sosidge

Bro could you explain more further??..
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Old 05-05-2004, 10:08 AM   #14
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Quote:
Originally posted by Wency_TA03R-PRO
sosidge

Bro could you explain more further??.. [/B]
Explain more further what how?
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