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Old 03-29-2005, 06:32 AM   #1
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Exclamation Battery Charge #'s...

I just purchased the LPR Pulsar Competition 2 charger and some GP3300 bulk cells. Upon my first charge I was fairly suprised to see 4100mah and 8.9v when it was complete? It charged at 5 amps a little over 45 minutes.

Does that sound good? bad?

Thanks!
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Old 03-29-2005, 06:45 AM   #2
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people get 4000 when charging, but charge number do not count, as the real numbers are when you discharge the battery... i guess you get 4100 because the resistance is high
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Old 03-29-2005, 06:49 AM   #3
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i can't remember the name ( maybe rc extreme) but one of the lastest issues of a magazine has a good article on what all the numbers mean, and shows you a way to make your own discharge graph.
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Old 03-29-2005, 06:52 AM   #4
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Input Mah is linked to output Mah but it's not a direct thing and it does vary quite a bit. I had some cells go to 4500 Mah on the first charge and regularly hit 4300 in subsequent charges. But Exe is absolutely right, the most important numbers are on discharge.

Chris
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Old 03-31-2005, 01:42 PM   #5
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well after running the battery I discharged it down to 5.4v and these are the #'s I got:

Discharge Current 10amp discharge
Discharge Voltage 5.4v

Displayed after discharge:
395s
7.08v
1089mah

Does that mean anything to anybody?
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Old 03-31-2005, 01:53 PM   #6
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Quote:
Originally posted by Nitro-Boy
well after running the battery I discharged it down to 5.4v and these are the #'s I got:

Discharge Current 10amp discharge
Discharge Voltage 5.4v

Displayed after discharge:
395s
7.08v
1089mah

Does that mean anything to anybody?

that ain't right... you should get approx 370-380 of runtime and 3000-3100 capacity at 30 amps, not 10... something's wrong there mate...
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Old 03-31-2005, 02:41 PM   #7
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Exe,

This was AFTER he ran the battery.

Nitro,

It means that after tour race you had nearly 400 seconds of run time left at 10A discarge, thats fine, nothing to worry about. You might want to gear up as you have a lot left in your cells.

Also I would suggest you do not discharge below 1v/cell. There is a slight risk of cell reversal.

Chris.
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Old 03-31-2005, 02:43 PM   #8
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Quote:
Originally posted by crimson eagle
Exe,

This was AFTER he ran the battery.

Nitro,

It means that after tour race you had nearly 400 seconds of run time left at 10A discarge, thats fine, nothing to worry about. You might want to gear up as you have a lot left in your cells.

Also I would suggest you do not discharge below 1v/cell. There is a slight risk of cell reversal.

Chris.
aah.. sorry, my fault didn't read that carefully
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Old 03-31-2005, 04:28 PM   #9
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The peak voltage # of 8.9 is telling you your pack is close to new and has pretty good internal resistance. As the packs get older, the peak voltage will go up. As internal resistance goes up, so will the peak voltage. 8.9 volts are a good peak.
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Old 03-31-2005, 06:48 PM   #10
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Thanks for everyones input!

Just to see I re-charged the pack fully and then ran a discharge to 5.4v (Before reading the 6v, I'll do that from now on):

Charge from 5.4v:
6amp
8.41v
3024mah

Discharge to 5.4v:
10amp
7.31v average
2615mah
948s
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