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Unread 21-01-2006, 09:45
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Joe Johnson Joe Johnson is offline
Engineer at Medrobotics
AKA: Dr. Joe
FRC #0088 (TJ2)
Team Role: Engineer
 
Join Date: May 2001
Rookie Year: 1996
Location: Raynham, MA
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Re: Battery Life, 50A load discharge test method/results

I did some tests several years ago comparing the Exide batteries to the CSA batteries that used to be in the kit to the Yuasa batteries.

I had a set up with a bank of very large (WATTAGE) resistors. I adjusted the resistance to draw 100 Amps at 12V (0.83 Ohm).

I defined a battery as "Dead" when it reached 8V (I think I picked 8V because that was the voltage that the radio at the time would brown out).

I measured the time it took the battery to go from fully charged to dead.

Anyway, "good batteries" would take 450-600 seconds. "bad" batteries would take 250-300 seconds.

Based on my experiments, I believe that unless your robot transmissions or ball handling mechanisms are extremely poorly designed, you will not have to worry about using up a good battery in a 130 second match.

Joe J.
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