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Old 04-30-2003, 09:17 PM   #16
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When u say 3300 went to 2800, you know this becuase when you first assembled them you cylced them and got 3300mah charge into them? Or your comparing charger numbers to stickers that came from a turbo matcher..


the only real way to monitor your packs quality or life span is to have a note book for your packs and use the same charger all the time

-Day one build and cycle pack record data(this is your benchmark for its life)
-cycle2
-cycle3
-ect ect
-Dont cycle every week once a month if your conserned with the packs numbers but remember compare the results to your own personal results found on day one of the packs life not the lables. Unless you own a turbo matcher and have the identical parameter u will not get numbers to match your lables at home, even with a turbo35.

A brand new pack may not charge up to 3300mah it may only go to 3000, charge mah is not important to me the only numbers i pay attention to when i cylce my packs is:
-dishcarge time in seconds
-average voltage
-internal res
All at 30 amp discharge if all u have is 10 or 20 fine just be sure to compare apples to apples.
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Old 05-01-2003, 12:42 AM   #17
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I have 3000 Peak Performance matched packs and I can get them to charge up to around 2800, and then I will put them back on the charger and another 300 or 400mah will go into them.

1) Is this safe?

2) Am I over-charging them? I heard you can't overcharge NiMH cells?

3) Is it safe to just charge them for another 300 or 400mah instantly after the charger says they are done when at 2800mah?
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Old 05-01-2003, 02:53 AM   #18
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Heat is the killer, particularly for the NiMH cells. If the cells are warm when they peak, and you start them straight away, you will damage them.
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Old 05-01-2003, 03:13 AM   #19
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Quote:
Originally posted by sosidge
Heat is the killer, particularly for the NiMH cells. If the cells are warm when they peak, and you start them straight away, you will damage them.
Damnit... i've been doing it this way twice a week for like 6 months! UGH!
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Old 05-01-2003, 03:44 AM   #20
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I think this is a useful link for everyone here. It has some interesting conclusions, like putting a fan on your cells whilst they're charging is bad for performance

http://www.users.zetnet.co.uk/pro-trak/tests.htm
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Old 05-01-2003, 09:22 AM   #21
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Everything that I have been told about the NiMH cells is that they need to be VERY WARM when it is time to race. They should be at about 140 degrees F when they come off the charger.

My practice has been to discharge my NiMH batteries to 5.4 immediately after running them. Then, before charging them I put them on a tray for anywhere from 5 to 15 minutes. I use the Indy tray, not exactly sure which one. I pull the battery off the tray and let it rest for about 5 minutes then put it on the charger.

Using a Turbo35 GFX, I consistently get about 3600 to 3900 MAH when charging. I don't cycle my batteries very often, so I don't have discharge numbers. This is over the course of 4-6 months with racing just about every weekend.

I know that on the original Turbo Matchers the final readings were taken at .9 volts per cell, but the discharge continued until .1 volts. This will give more charge MAH. I believe this is the number the cell manufacturers are putting on the cell, not just the number down to .9 volts.

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Old 05-01-2003, 09:26 AM   #22
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The labels on my cells always have a cutoff at .90 not .10, so 400+ seconds is at 30 amps down to .90/cell. Which is about normal for 3300's.
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Old 05-01-2003, 09:36 AM   #23
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Hi Guys,

So let me get this straight:

1. Never use a fan when charging NIMH (But I can use it when discharging right?)

2. After discharging, use the Octane 2 or Real Time 2 to discharge further, just until the lights go out.

3. If we do discharge a NIMH pack, we should use 20 amps, and not 10.

But I have some questions:

1. What is the discharge amp of Dean's Light bulbs?

2. I've been using a volt meter to watch my NIMH packs discharge to 5.4 on the deans bulbs, is this ok?

3. Could i use the Indi Reactor 20 without worry?

Your help is greatly appreciated....

Buddha
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Old 05-01-2003, 10:10 AM   #24
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Its probably best to let the cells cool naturally during discharge. Using a fan will cool the cells but only the outer layer of the cell so it won't cool evenly.
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Old 05-01-2003, 10:24 AM   #25
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RcBhudda

From what my experience is that by using a discharge
tray you can equalize your cells (dis charge till each light
goes out) rather than discharging using something that
drains the pack and not knowing what you have discharged
each cell to.

Hope this helps
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Old 05-01-2003, 03:26 PM   #26
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Hey I got capacity back up in my cells. All i did was discharge all my cells with an indi 30amp discharges(cuts off at 5.4v). Then i charged them back up on the pulsar (5am, 20mv delta peak). The first time i did it my cells went from 2800 to 3000, the second time they wnet from 3000 to 3300-3400, I'm on hte third cycle. The voltage for all the cells are up. Cycling really did bring them back YEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
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