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Old 10-14-2001, 08:06 AM   #16
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Hello. I have a few questions about Ni-Cd batteries.

I was told that charging a Ni-Cd pack the second time in one day is actually better. True? Yes/no.

I read somewhere that jumping from different charging rates rapidly (I.E., 4.0amps on 1st day, 4.5amps on 2nd day, 6.0amps on 3rd day, etc etc.. hope you know what I mean) is bad for the pack. True? Yes/no.

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Old 10-14-2001, 04:48 PM   #17
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Aurra - I don't think charging them twice in a day hurts them, just as long as they have enough time to cool. I don't run my NiCads mor than once per day.. nomatter what, but they usually get a couple hours to rest between uses...

NiMah like the second go around though...

I don't know much about rates... I always charge my packs at the same rate per pack... but i change for diff. capacitys..
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Old 10-16-2001, 07:35 AM   #18
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Hi everyone, i need to know if you have ever use a Yokomo Yz-bms charger and were can i find a picture of it?
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Old 10-16-2001, 10:32 PM   #19
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has anyone here have any experience re-peaking nimh 3000mAh batts regularly?

i was thinking of charging during the evenings and then re-peak in the morning before running the car.

any opinions? thanks!
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Old 10-17-2001, 06:02 AM   #20
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I usually re-peak right before putting it in the car, but that would probably work. I know someone who charged his packs at home, and peaked them at the track. Thats always nice so you can get practice in right when you get there.....

I personally just charge at the track...
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Old 10-17-2001, 03:17 PM   #21
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I charge my 2400's at 4.5 then repeak at 6.0 right before I run them, when the race before mine goes out, that's when I hit the Start button. I've only got 4-cell SMH 3000's, charge them at 4.0, no repeak.
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Old 10-17-2001, 04:48 PM   #22
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What Delta voltage are you guys using for the SMH. I'm currently using 30 mV/pack on my Millenium. I've seen some new chargers that are using 50 mV. Is 30 mV too low?
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Old 10-17-2001, 05:04 PM   #23
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I'm using 3mv per cell, or 18mv per pack for my cutoff. My INtegy 16X5 charger recommends between 3 and 5mv per cell, so you're ok with 30mv per pack. I wanted to stay on the lower end to keep the packs from getting quite so hot.

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Old 10-17-2001, 08:35 PM   #24
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i just had a thought. i normally charge at 4 amps at 36mV/pack voltage threshold. they just cozy warm after a charge.

once in a while push the car at full throttle until the battery drops. when i touch the batts after this excercies they pretty hot!

now, since they normally get that hot, wouldn't it be okay if we charge them at the higher voltage threshold? it'd get hot but not as hot as using the batts at full throttle.

ideas anyone?
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Old 10-17-2001, 10:06 PM   #25
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I was always told that when a pack starts getting warm on the charger, it's done... The extra electricity can't go into the cells, so it becomes heat. That's what I've been told, and it makes lots of sense. So, why make a pack get hot while charging it?
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Old 10-18-2001, 12:52 AM   #26
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i was just thinking that if the pack normally gets hot on regular use then it may be safe if it gets hot while charging.
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Old 10-18-2001, 10:29 AM   #27
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Quote:
Originally posted by spider
i was just thinking that if the pack normally gets hot on regular use then it may be safe if it gets hot while charging.
The biggest difference is that when you run the car you are taking electricity out of the cells, when you are charging you are putting electricity into the cells. Don't push the charging temp too high with larger currents because soon you will hear the "pissss" sound from your cells venting and it will be "bye bye pack!"
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Old 10-18-2001, 07:02 PM   #28
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a friend of mine overcharged his 3000 SMHs and one cell has a torn plastic cover and the metal can was showing already. he said that it happened after using it.

my 3000 SMH is now on the decline. they only get up to the 2600 to 2700. i keep a record of the charging that i do -- amp rate, threshold, time, mAh -- and after about 30 - 40 uses the capacity went down. i was charging at 4.5 amp with a 8mV threshold/cell (the lowest of the old millenium). sometimes i'd go up to 5 amps. these days i just charge at 4.0.

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Old 10-19-2001, 07:55 AM   #29
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Spider

Its possible that you have been over charging your SMH's. Your current threshold is 48 mV per 6 cell pack. your threshold should be about 30 mV per pack. YOu can trick your older Millenium in to using a lower threshold by changing the number of cells charged from 6 to 4 to get a lower threshold per pack (4 cells X 8mV = 24 mV per pack).
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Old 10-20-2001, 07:05 AM   #30
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I've many bad problems with Panasonic's, how about you guys...
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