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Old 12-22-2009, 10:38 AM   #91
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Originally Posted by syndr0me View Post

This is a no-brainer. Just like heating packs and charging at 1C. It's an easy fix, and any charger that's not broken should handle it just fine.
I charge a couple of my newer packs a 2c, they are built for that now. Chemistry changes is batterys is coming in leaps and bounds, hence the reason why it is not damaging to charge a lipo to 8.44 anymore, on an older pack, yeah over time it is bad, but not anymore.

I am glad to see ROAR trying to keep up with the tech, and this is one rule that is good for keeping tech back at the main show,(not the idea of not having a tolorence, but the general idea) I was just put back at first about the cheating attitude.
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Old 12-22-2009, 10:59 AM   #92
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I feel it should have been left the same it just causes problems and makes people spend more money that sent there chargers out to get the update and now has to send it back to to get it re updated if possible. This makes me laugh for .04 of a volt. Sometimes things are better if left alone...
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Old 12-22-2009, 11:21 AM   #93
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Ya, but the people that are willing to chase after 8.44 volts (.04V over "legal") with 100's of dollars can now chase after 8.404V. (assuming we are rounding that way).
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Old 12-22-2009, 11:24 AM   #94
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So is there a tolerance on battery tempature? What if you run the same battery in two classes and they are close together and it's a little warm? Or is tempature tech going to be the place the hand on the battery and make sure its not obviously heated?
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Old 12-22-2009, 11:36 AM   #95
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Originally Posted by syndr0me View Post
ROAR got it right with this one.

The damage done by slight overcharging is cumulative, and can eventually lead to a pack that's more prone to fire/damage. Also, people were using NiMH mode to "top off" their packs to 8.44v.

This is a no-brainer. Just like heating packs and charging at 1C. It's an easy fix, and any charger that's not broken should handle it just fine.
Negative...I have the same pack for over a year now and still looks brand new and my charger charges it to 8.44 everytime. No issue what so ever...
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Old 12-22-2009, 11:49 AM   #96
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You guys are hilarious. Seriously take a look back at what you are writing.

This is a simple case of the few ruining it for the many.

There is no difference in saying if you battery is over 8.40 your out and say if it's over 8.44 your out. The supposed inaccuracies are still there.

So why weren't any of you with the 8.44 chargers worried about going over 8.44?

Maybe I'm missing something, are you're chargers highly accurate at 8.44, so no tolerance needed, but highly inaccurate at 8.40, so you needed the tolerance?
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Old 12-22-2009, 11:51 AM   #97
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I feel it should have been left the same it just causes problems and makes people spend more money that sent there chargers out to get the update and now has to send it back to to get it re updated if possible. This makes me laugh for .04 of a volt. Sometimes things are better if left alone...
Why is that any more humorous then those same people spending money sending out the chargers after an extra .04 of a volt?

The chargers were fine before hand.
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Old 12-22-2009, 11:56 AM   #98
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Maybe instead of worrying about the .04 volts for 2 cell it would be a better to go after the guys running their single cell cars after they have obviously dumped. The failure mode of over discharge is just as bad as the failure mode of overcharge. Where's the rule on that one?

I hear some people spout off that the new cells are some how able to handle overcharge but I don't see a single pack that tells you in writing that it's OK to charge above 4.2 volts per cell. Show me in writing where the cell manufacturers allow overcharge above 4.2/8.4 v. It's got to be all of the approved manufacturers and not just one or two...

I do see plenty of new packs that say in writing that they can be charged at 2C (or higher). Maybe we could allow a charge rate specified by the cell manufacturer...
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Old 12-22-2009, 11:59 AM   #99
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Why is that any more humorous then those same people spending money sending out the chargers after an extra .04 of a volt?

The chargers were fine before hand.
HK had peoples charge to 8.6V to race !

so all control under 8.4V to race NOW !
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Old 12-22-2009, 12:02 PM   #100
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so the $400 I spent on a brand new GFX in July 2009 was a waste of money because now I have to send it back for probably $100 and get it bumped down to 8.39 so i don't have to worry about it just incase their volt meter is not the same as roars
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Old 12-22-2009, 12:12 PM   #101
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so the $400 I spent on a brand new GFX in July 2009 was a waste of money because now I have to send it back for probably $100 and get it bumped down to 8.39 so i don't have to worry about it just incase their volt meter is not the same as roars
Yes, but don't complain to ROAR about the fact that Competition Electronics didn't make this adjustable... It's not that hard and they should have made it adjustable in the first place.
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Old 12-22-2009, 12:24 PM   #102
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Yes, but don't complain to ROAR about the fact that Competition Electronics didn't make this adjustable... It's not that hard and they should have made it adjustable in the first place.
Yep.. or he could simply stop his charge manually right at 8.4.
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Old 12-22-2009, 12:29 PM   #103
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Negative...I have the same pack for over a year now and still looks brand new and my charger charges it to 8.44 everytime. No issue what so ever...
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2. OVERCHARGE – LiPos are extremely non tolerant to an overcharge condition. A standard charge profile is CC/CV to 4.200V. Drastically overcharging a cell just once is a sure way to send a cell into thermal runaway. Overcharging a cell slightly but repeatedly is also extremely bad for a cell. For example, it you charge a cell to 4.300V, the lithium ions start plating on the electrodes forming lithium metal. Lithium ions are not flammable, but lithium metal is. Every slight overcharge cycle will plate more and more lithium metal resulting in a battery that is very prone to igniting.
So what x-ray machine are you using to see that your electrodes are getting plated with lithium ions. You realize the plastic case on your pack you're "looking" at isn't actually part of the battery, right?

And anybody that spends $400 on a LiPo charger that can't have its firmware updated by the end user, or doesn't have a variable cutoff should probably reflect on why you'd do something so foolish when there's $30 chargers available that do exactly the same thing, but with more features like balancing, and at 1/100th of the size.
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Old 12-22-2009, 12:31 PM   #104
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Yep.. or he could simply stop his charge manually right at 8.4.
Please tell me how to stop the charge manually on the charger below which gave me a charge of 8.41 and 8.42 at the Halloween Classic (as well as 8.37)

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Old 12-22-2009, 12:43 PM   #105
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I am laughing so hard i just peed myself, 5 pages of complete and total nonsense.
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