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Old 02-13-2003, 07:24 PM   #1
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Default Whats the point of discharging?!!??!!

Man there are alot of like 100 dallar things out there solely for DISCHARGING, wtf is the point of it? u charge ur battery and go....... Why discharge? I made a home-made one wit a lightbulb and stuffs.. but why discharge?
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Old 02-13-2003, 07:43 PM   #2
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Umm...simple...You don't usually run the pack's full charge out in a race. Leaving charge in there for extended periods of time, multiple times will hurt the peformance of the pack and reduce its life. If you're running every weekend, dump your packs down to 5.4 v until the next week, that way they stay fresh. And by the way dischargers don't cost $100, you're being ripped big if someone tells you that's what they cost. You can pick up a decent one for like $30 from Integy.
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Old 02-13-2003, 10:46 PM   #3
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- Cell memory. If you don't discharge you batteries, and this is particularly noticable with nicads, they retain a cell memory, and on succesive charges, they will "think" they have less capacity than they really do. It also seems to affect more than just capacity.

Basically I would always recomend you discharge your packs after each run, put nicads on a discharge tray for 30 minutes and store them fully discharged, and from time to time you might want to tray nimh's also, but for no longer than 5 minutes for the more sensitive types (SMH, UMH) and those same sensitive batteries will also be safer if you put a bit of charge back in them to store them.

Have fun,
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Old 02-14-2003, 08:11 AM   #4
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Is a lightbulb with wires an ok discharger? thats what i been using.........
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Old 02-14-2003, 08:15 AM   #5
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What kind of batteries do you have?
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Old 02-14-2003, 08:35 AM   #6
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The only problem with the light bulb discharger is the inability to cutoff the discharge at a set voltage. Deans does make a Black Box that can be used between the pack and the bulbs to give this cutoff.

Discharging a 6-cell pack below 5.4 volts will put you in danger of damaging cells. Even on a matched pack, the cells do not discharge exactly the same. Some cells will be discharged before others. If you continue to discharge a pack, those cells that are already discharged will be getting a reverse charge from the other cells in the pack.

So, you discharge a pack to 5.4 volts and then you can use a tray to discharge the individual cells more deeply. Traying was absolutely critical on the old NiCads, but not as important for the NiMH.
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Old 02-14-2003, 10:23 AM   #7
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Right now my starter batt's are 2 DYNOMITE 1700's and a really really gay 1200 HPI battery (came with car)


Well, i just used my light bulb rig and i just waited till it was only glowing a small bit then i cut it off.
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