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Old 06-11-2003, 10:09 AM   #16
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Quote:
Originally posted by trf man
i can get my sanyo 3300 up to 1.8 volts after each peak.plenty of runtime to.
1.8v for peak when charging is not good. This generally indicates that the cell has high internal resistance. For a 6 cell pack you are looking at a peak voltage of 10.8v!!

The voltage everyone is talking about is the avg discharge voltage!
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Old 06-11-2003, 10:10 AM   #17
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Quote:
Originally posted by redsand
well, mine aren't opened yet. they're still in the plastic wrapped box. dunno what the voltage readings would be when they are charged.
Don't keep them like that for too long. New cells normally only hold a nominal partial charge. If stored for too long they start to die.
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Old 06-11-2003, 10:12 AM   #18
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Quote:
Originally posted by trf man
i can get my sanyo 3300 up to 1.8 volts after each peak.plenty of runtime to.
1.8V??? It won't even power a mini-z.
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Old 06-11-2003, 09:57 PM   #19
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Quote:
Originally posted by dtm
Don't keep them like that for too long. New cells normally only hold a nominal partial charge. If stored for too long they start to die.
will do soon, still waiting for the plastic shrink wraps.
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Old 06-11-2003, 11:06 PM   #20
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Quote:
Originally posted by dtm
1.8v for peak when charging is not good. This generally indicates that the cell has high internal resistance. For a 6 cell pack you are looking at a peak voltage of 10.8v!!

The voltage everyone is talking about is the avg discharge voltage!
Wow...peaking at 10.8V? Isn't that unusually high? Most of my GP baterries are peaking at below 9.0 Volt (From what I know, it is better when a battery peakes at a lower Voltage).

A.W
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Old 06-12-2003, 05:51 AM   #21
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sorry,but i dont see how a battery peaking at a lower voltage is good.at the end of the charge i see the voltage on a voltmeter as 1.8 volts per cell.surely higher voltage is better.
well i can out accelerate any car at my club.
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Old 06-12-2003, 06:27 AM   #22
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Hi guys. Greetings from Malta.

I have been following this thread and trying to learn.

From my experience, you are lucky if you get a whole season out of a pack of cells before they start loosing run time.

We run 16 meetings a season - every second weekend. So our race cells will have 30 cycles on them at a maximum. We are at the end of season now and to keep them giving us 5 minutes run time we are down 2 teeth on the pinions we were running at the start of the season.

As for charge voltage, this varies on different cells. I run Sanyo HV and my son runs Panasonic UMH. Both are 3000 as we have a 3000 top limit this season. From new the Panasonics peaked out at about 9.2 volts, whilst the Sanyos peaked out at 9.6 volts - all the packs.

Now that they have accumulated internal resistance they peak out later - 9.5 for the Panasonics and about 10 volts for the Sanyos, but are in fact quite a bit slower.

There has been mention of the various trays. The Orion trays stop at .5 volts per cell. The Trinity stop at ZERO. So how does someone, who contributed earlier, get his Trinity trays to stop at .9 volts. I haven't trayed my cells except about once every 3 months, just to equalise.

regards

Joe from sunny Malta.
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Old 06-12-2003, 07:01 AM   #23
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Ah...Joe. Perhaps we can talk about something not Xray related!

I don't know if you can get the GP3000 cells in Malta. Even for loose cells they are not too bad, around 1.14-1.13v @30A. They are lighter than the GP3300 and I have found that they are much more robust in terms of losing runtime with age. Also pretty much 99% of the cells start life at more than 3100mah on 30A discharge. If you are struggling for runtime and are restricted by 3000 cells, these are a good option.
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Old 06-12-2003, 07:51 AM   #24
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I'm using the Robitronics discharge tray. I can leave my batteries on this tray. Won't overdischarge; voltage goes down to about 0.74-0.75 volts per batt if I leave 'em overnight (accidently) and the voltage maintains there. Usually when the lights go out it's about 0.89-0.88 volts per cell.

I found that equalizing my nimh cells this way every 5-6 runs gives me back my run time. Punch & top speed can't feel much difference though.

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Old 06-13-2003, 01:32 AM   #25
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Hi DTM. Greetings from Malta.

Actually we only have 1 round of this season's championship left, that's Sunday week, so I will be able to ditch my 3000s for racing since I understand we will be going to 3300 next season.

Son Josh and I are doing a couple of race meetings in England in August, so I already have some GP3300s from Corally which i hope to build up in a couple of weeks time.

The figures on these are 420 run time and 1.171 volts. All 8 packs are about the same figures. Looking at some other figures quoted in previous threads that doesn't seem to be bad.

Whilst Josh still runs the TC3 - he is National champ again for the 6th time with 14 wins in 14 starts this season, I have progressed to the SD Yoke, which I like very much. Actually I have won the stock championship this year too so we have had a pretty good season.

Regards

Joe from sunny Malta.
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Old 06-13-2003, 08:18 AM   #26
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Hi Joe. It will be interesting to see how the recent batches of GP3300 last (don't know if anyone else has got comments on the latest batch?). I know they have changed the manufacturering process to really kick out the voltage. But with the previous batches they would be great cells when new and after around 10 cycles they would start to die off. After around 20-30 cycles they would be ready for the bin.....26xxmah @30A discharge with a big drop in voltage across the range!! This is the only reason why I have continued to buy the GP3000.
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Old 06-13-2003, 09:52 AM   #27
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We have ProMatch GP3300 packs and do not tray them. ProMatch says you can but in the past when I put them on a Trinity RT2 tray, they went too low for my Millenium Pro to detect. I had to use a lesser charger, like the Indi 16X3, to get them started. Weird. ProMatch recommends their tray, the Smart Tray 2.

We just use the Indi Reactor 20 device to discharge the cells to the built in cutoff. Have not noticed any significant power or run-time loss.
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