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Old 06-20-2008, 08:27 AM   #61
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I agree that there's no need for more than one pack except if you're practicing a lot. Two is more than enough even if you're running a bunch of practice.
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Old 06-20-2008, 08:43 AM   #62
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Originally Posted by Fred_B View Post
I agree that there's no need for more than one pack except if you're practicing a lot. Two is more than enough even if you're running a bunch of practice.
+1

I have 1 lipo now and I can get 6 pratice runs in a 3 hour pratice session. I'm used to having two lipos but I have made due with one and it may stay that wait for a little bit. My motor doesn't cool down fast enough for me to get the full benefit of 2 packs.
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Old 06-20-2008, 08:43 AM   #63
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There's really no reason to start yelling and getting obnoxious.

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What their pack magicaly caught fire because it was in a car? I smell BS...
No BS at all, and I would think that would be why anyone that didn't use a charge bag as a hat would be smart enough to use one for it's proper purpose.


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Balance charging is not a gimmick, it only takes a small amount of logical thinking to understand why.
If one cell becomes discharge lower than the other, the higher charged cell will subsequently be overcharge and start to puff.

Oh and PFM are crooks..
First off, a quality charger is going to recognize the higher-charged cell first - and I think if you had read the link you would have understood their logic behind their suggestion on why they're potentially a waste.

And I don't think there is any reason to make libelous statements unless you care to back them up with facts.
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Old 06-20-2008, 08:46 AM   #64
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Originally Posted by Kevin K View Post
I have seen more lipo's blow up or puff up charged at lower rates(less than 1C) then higher rates(over 1C).
OK, rofl, you can go with that if you insist.
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Old 06-20-2008, 08:58 AM   #65
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Originally Posted by RocketRob40 View Post

No BS at all, and I would think that would be why anyone that didn't use a charge bag as a hat would be smart enough to use one for it's proper purpose.

First off, a quality charger is going to recognize the higher-charged cell first - and I think if you had read the link you would have understood their logic behind their suggestion on why they're potentially a waste.

And I don't think there is any reason to make libelous statements unless you care to back them up with facts.
There was no reference to lipo sacks. You posted as if charging in a car is somehow more danagerous than charging outside of a car. If you want to use a lipo sack then agreed that's without a doubt the ultimate in safety.

It doesn't matter how high quality a charger is, if it doesn't not monitor the tap it cannot know the true voltage of each cell.

PFM have come out with some rediculous statesments many times before, they were on radio control zone forum spouting crap years ago. Many people had problems with thier manganese packs and PFM didn't help them at all. Their attitude stank!
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Old 06-20-2008, 09:06 AM   #66
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Apogee can say what they want but each cell manufacturer will tell you "do not overcharge your pack" The cells in the pack should not be charged above 4.2 volts (each cell) and balance charging is the only way to guarantee each cell will not get overcharged.

A new pack that is properly matched won't benefit much from balance charging provided that it's taken care of properly. An old pack on the other hand is a different story because the cells won't degrade exactly the same over time. A LiPo will go out of match just like any other battery pack regardless of chemistry.

The gimmic comment is pretty funny though. LiPo was a gimmic at first. So was cell matching in the old days of NiCd's. Now both are the norm. Wonder how long it will take for everyone to start cycling their LiPo's like SMC. Oh, wait, that's just a gimmic and it could never be used to sort out bad packs before we get them.
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Old 06-20-2008, 09:37 AM   #67
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Originally Posted by JevUK View Post
There was no reference to lipo sacks. You posted as if charging in a car is somehow more danagerous than charging outside of a car. If you want to use a lipo sack then agreed that's without a doubt the ultimate in safety.
All I was referencing was someone's claim to "charging them in the car" and you cried BS!!

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Originally Posted by JevUK View Post
It doesn't matter how high quality a charger is, if it doesn't not monitor the tap it cannot know the true voltage of each cell.
If the cells are cheap, and not close to being matched, you're right there is no way to tell. But that's true with any sort of cell - lipo or nimh.
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Old 06-20-2008, 09:39 AM   #68
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As for the comparison of apples to oranges (based on capacity), my understanding is that with LiPo, because of how the cells work, you can make those comparisons and generally be very close in your findings. That is, if it's the same cell design/chemistry. I asked the same question early on, and that's how it was explained to me.

Kevin: Nice quote. :-D I need to quit saying those things, it creates too many enemies.
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Old 06-20-2008, 09:46 AM   #69
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Originally Posted by Fred_B View Post
Apogee can say what they want but each cell manufacturer will tell you "do not overcharge your pack" The cells in the pack should not be charged above 4.2 volts (each cell) and balance charging is the only way to guarantee each cell will not get overcharged.

A new pack that is properly matched won't benefit much from balance charging provided that it's taken care of properly. An old pack on the other hand is a different story because the cells won't degrade exactly the same over time. A LiPo will go out of match just like any other battery pack regardless of chemistry.

The gimmic comment is pretty funny though. LiPo was a gimmic at first. So was cell matching in the old days of NiCd's. Now both are the norm. Wonder how long it will take for everyone to start cycling their LiPo's like SMC. Oh, wait, that's just a gimmic and it could never be used to sort out bad packs before we get them.
Good points, and maybe we missed what the other was saying - so I'm just going by what one company's website suggests for example purposes.

But I will say that Apogee says a couple of things relative to balancing - "Due to misinformation, more packs have been damaged during balancing than have been helped. If you insist on balancing a pack (If it makes you feel warm and fuzzy inside, and you sleep better at night, have at it), please, please, only balance fully charged packs.... Why only balance fully charged packs? All properly matched cells are mated together so that the high and low voltages will coincide. There may be mid-point voltage variances. Balancing a partially charged pack can cause the high and low voltages to become unbalanced. Again, please, if you insist on the balancing gimmick, please only balance fully charged packs."

And they also offer a "No Fault lifetime replacement program" which sure sounds good as well as not at all sounding as if they abandon their customers.
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Old 06-20-2008, 10:09 AM   #70
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Not sure where your love affair with PFM stems from. The only time I've seen them is when people have had problems and the PFM rep becomes abusive. Their statement on balancing is incorrect, you will not damage a pack by balance charging. It's a lame way for them to try and convince the public that their packs are better because they match cells. I'm not saying matching cells is a bad thing but balance charging is better for saftey.

You should never discharge your lipo's to zero so their statement of mid point balancing is pointless
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Old 06-20-2008, 10:25 AM   #71
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Not sure why you seem so intent on bashing them, unless of course you're pushing a competitor's packs as you do in your sigline, it seems to be a moot point relative to your complaint since they clearly say on their website "No Fault lifetime replacement program". I mean have you personally ever had any of their packs, or are you just trolling?

And I don't know where you get the "discharge your lipo's to zero" idea, because they say no such a thing and all their packs come with instructions saying not to do just that.
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Old 06-20-2008, 11:39 AM   #72
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Quote:
Originally Posted by RocketRob40 View Post
Not sure why you seem so intent on bashing them, unless of course you're pushing a competitor's packs as you do in your sigline, it seems to be a moot point relative to your complaint since they clearly say on their website "No Fault lifetime replacement program". I mean have you personally ever had any of their packs, or are you just trolling?
When you invest time in researching what lipo's to buy you find some companies are more helpfull and truthfull than other. Maxamps, Tanic and few other I found to be very honest, helpfull and they did not feel the need to criticize other brands to sell their own. PFM's policy seemed to be the opposite. I've witnessed them refuse to honour their waranty when blaming their customer for mis-operation. They'd need a lot more than a lifetime waranty to convice me they have changed.

Why do you even care anyway? It's not like they even sell hard cased packs .

Quote:
And I don't know where you get the "discharge your lipo's to zero" idea, because they say no such a thing and all their packs come with instructions saying not to do just that


Sorry if my sentance was not clear enough :

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You should never discharge your lipo's to zero
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Old 06-20-2008, 12:58 PM   #73
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I had a bad lot of Apogee packs. Over winter they puffed on me, without me using them. Stored them according to spec and took them out at a later date and they were puffy. PFM replaced them without any problems. They told me it was a issue with the particular packs I purchased. Gave me a full credit for new packs.

I'm not posting to show love for PFM, as I had a small run in with them on a different issue (not related to battery problems). However, from my dealings, they do back what they sell.

The lifetime warranty isn't much of a warranty if you ask me. It only gets you a discount on a new pack if you screwed up. Yea, it's nice to get a discount, but that isn't much of a "Lifetime Replacement Warranty". What it does it that it gets you to buy another pack from them. I'd be hard pressed to believe that they still didn't make money off the pack, even with the discount...
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Old 06-20-2008, 01:13 PM   #74
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Sorry if my sentance was not clear enough :
it's either not clear or it's hard to comprehend the point you're trying to make when you bring it up like it's some new idea or something.
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Old 06-20-2008, 01:27 PM   #75
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Originally Posted by syndr0me View Post
As for the comparison of apples to oranges (based on capacity), my understanding is that with LiPo, because of how the cells work, you can make those comparisons and generally be very close in your findings. That is, if it's the same cell design/chemistry. I asked the same question early on, and that's how it was explained to me.
On the chemistry side I would tend to agree but the two cells will have totally different internal resistance. I would assume that IR is pretty important along with how efficient the cell is at accepting charge.

I have well over 200 cycles on my Orion pack without issue so it's not killing my cells. Your results may vary.
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