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Old 04-23-2003, 04:56 AM   #31
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So when the charger/pack passes 1500 mAH, there's no more falsepeaking? And the charger go straight forward, untill it finally cut off and the pack are very very hot? If so, what's the capacity then? And what's the peak voltage?
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Old 04-23-2003, 05:06 AM   #32
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Most of the time it will false peak about two or three times, first around 750mah, second around 1500, third time around 2700, again these are just ball park figures and do vary, but you get the idea. Everytime it false peaks it basically starts over, so instead of continuing from 750mah the little digital figures will start from 0 instead of 750, so I have to add them up each time. But they do top out at just about 3000.
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Old 04-23-2003, 05:18 AM   #33
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Hmmm, bad the counting starts over....

However, I dont believe that for example 2700 is a false peak.

When I started out with Sanyo 3000 HV, the first charge went well over3200 mAH (dont compare with your numbers, I'm using another charger. But it'll give you an idea). I cant remember the second charge, but I believe it was in the 2500-2800 area. So I restarted, and the pack get extremely hot !

After that I've noticed that this pack always cut off in the 2500-2800 area. It depends on how they are discharged, how long it have rested and how many charges the same day. In the beginnign, I often got tempted to restart the charge. And always, the pack heated up way too much.

Dont count too much on the chargers reading, versus the pack label. Because chargers measures differently, and it depends a lot on how the pack are discharged.

If I discharge at 10 amps down to 2,50 volt for the pack, there's still some juice in the pack. But if I equalize them down to 0,6 volt pr. cell (=3,6 volt for the pack) on a slow equalizer, the pack will charge 2-300 more mAH's. But in the last case, it'll also false peak !

Long story.

To boil it down: Dont restart the charge, when capasity is over 2500 mAH.

Try this, and I believe that your heat problems are gone.

Now, for the false peak, I thinkt it's due to discharge process / storage / rest period / uses pr. day. Try and describe how you do these things, and I'll try to help.
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Old 04-23-2003, 05:29 AM   #34
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I'd just like to say thanks for all the help I really appreciate it.

I try to charge each pack only once every race day, sometimes I charge them twice a day but that is very rare. I discharge them at 20amps and just let it go until the charger starts beeping to let me know it's done and the pack is super hot.
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Old 04-23-2003, 01:53 PM   #35
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Does anyone ever tell you that you need to let your battery cool before you can re-charge them? and get a 30A discharger for a change. Also, get a Vornado fan or something small to cool both the battery and the charger. Basically right now, you are abusing your Peak batteries. You need sufficient cooling between charging and discharging and/or cycling your Nimh batteries. There is about more or less two hours difference between charging and discharging for Nimh batteries depending how much cooling you provide to the batteries and the charger. If you don't do that nor you don't provide enough cooling while charging and discharging or enough cooling after the battery had been used for a race or being cooled while discharging, you are going to destroy your batteries (it's kinda harsh but it is the reality). This is what I did with my old and used Radio shack Nimh: .02v and 1A. It's a painstaking long wait but it will ensure there will be no false peaking. After awhile (refreshened), I can start charging them at about 4A and I have no problem ever since.

Start cooling your batteries and charger while charging and you will see the difference, my man. It sure helps not to waste your 350 bucks went out the window just like that.
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Old 04-23-2003, 03:23 PM   #36
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You should let your batterys cool down befor rechargering them.
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Old 04-24-2003, 01:37 AM   #37
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Accord have already stated, that he only uses each pack once pr. day.

Accord, I believe you can get rid of those false peaks, by doing this:

After each run, discharge the pack with your charger to 5,4 volt. When the pack are cooled down, put a little charge into them. I'm putting aound 300 mAH into mine. Store them this way. Immideately before next charge, discharge the pack on your charger to 5,4 volt, then charge.

If you need to store the packs for more than 2 weeks, give them a single cycle every two weeks.

If you got an equalizer, equalize them once in a while, around once for each 5 runs.

NEVER deep discharge them, even not on a equalizer.

Hope this helps.
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Old 04-24-2003, 06:44 AM   #38
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How do I discharge them to exactly 5.4 volts? There is no setting or anything which lets me set that, the only setting for discharging I can set is the amps at which is discharges.
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Old 04-24-2003, 02:33 PM   #39
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Quote:
Originally posted by Accord
How do I discharge them to exactly 5.4 volts? There is no setting or anything which lets me set that, the only setting for discharging I can set is the amps at which is discharges.
I'm not familiar with your charger, but probably it's stated in the manual. Otherwise you could simply watch it during discharge and notice the cut off voltage - chances are great, for it default cut off at 5,4 volts. And if it's 5,2 or 5,6, it wont make much difference.
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Old 04-24-2003, 02:49 PM   #40
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Contrary:

Discharge your pack before charging. Use a tray (yea one of those things for only NiCDs) And leave the batt on the try for about an hour or two. Then about 20 minutes before you charge, take the pack off the tray. you can also tray the night before.

Your packs will be showing 3000 again. If your charger has a discharger, watch how much mah come out of the pack when it cuts off. Chances are its about 2000 mah, in which casse there is still around 800 in the pack, but it doesn't have enough oommph to push it out under a 20 amp load. If you put a small load on it from there (tray) it will continue to run about 30 minutes.

Don't worry about over discharging becase with a tray, there is a .9 volt per cell Diode that won't let more current go through.
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Old 04-24-2003, 02:57 PM   #41
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Quote:
Originally posted by Pit Crew
Don't worry about over discharging becase with a tray, there is a .9 volt per cell Diode that won't let more current go through.
This depends on which tray that is used. Trinity Real Time 2 and Integy Octane 2 goes all the way down to zero. And usually, active equalizers with auto cut off, stops at 0,6 volt pr. cell, which are too low for NiMh. In my case, using an EQ with 0,6 volt pr. cell, results in false peaks on the next charge.

So check out the specs of your tray, before use it with NiMh.
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