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Old 01-18-2008, 05:38 PM   #46
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IF you go to 4500 packs and up might as well go Lipo.

In a year or so I'll go to 4000 packs.

My bad. I thought he was talking about his old race cells he used last year in 2007.
sparksy Robbie races with me so you probably never even met this guy...please leave me alone...
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Old 01-18-2008, 06:07 PM   #47
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218? I payed 144.90 for *4* prebuilt packs already have Dean plugs installed and everything even shrinked for me.
People just think the most expensive packs will win races.
Might give you an extra edge but that's about it.
Tottally untrue. But yet the more powerful battery the more they cost.
I'm using those 3600 packs not switching anytime soon.
The packs that really caught my eye though were the team checkpoint side
by side assembled batteries, yet I was iffy making saddles out of them.

IF you go to 4500 packs and up might as well go Lipo.

In a year or so I'll go to 4000 packs.
Dude, What drugs are you on? Are you trying to compare your 3600 NiMH packs to his Lipo?
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Old 01-18-2008, 06:49 PM   #48
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WHAT CAN YOU DO TO A LIPO???

Theres plenty of punch, and runtime. yet some people want more voltage.

I was experimenting with an old Lipo cell. i wondered what would happen if i charged it and held it at 4.3vpc.

With the Motor running feature on my Superbrain 989, i set it to run at 4.3V at less than 1 amp. the chager will only put out 1 amp until it reaches the voltage, of which then it'll reduce current to keep the voltage. it works just like a normal lipo charger. I verified the voltage output, and it was precise, holding at 4.3v. the cell came from an old airplane pack that was in a crash. it was about 1100mah.

Anyway, at the end of the charge (which i watched very carefully), the cell puffed and was warm. i set it outside and waited. overnight, it shrank back to normal size. i measured the voltage and it was dead. 0 volts. Nada!

YOU CANNOT GET EXTRA VOLTAGE FROM A LIPO.

So, what puzzles me is, why match Lipo cells when you cannot get any extra voltage out of them? and its not like having IDENTICAL capacities is going to make a difference in racing. you're not going to pull that much amperage. AND you're not going to be using a lipo for its whole capacity in normal racing applications. in a stock buggy, i only use about 1000 mah in 5 minutes. with a 3800 Apogee, i could run all my qualifiers with one pack. and i'm definatly not going to feel the difference between matched pack and not.

The bottom line is, There WONT BE A VOLTAGE WAR anymore with lipo. Besides, the ROAR lipo rules state 8.4 volt lithiums only.
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Old 01-18-2008, 09:43 PM   #49
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WHAT CAN YOU DO TO A LIPO???

Theres plenty of punch, and runtime. yet some people want more voltage.

I was experimenting with an old Lipo cell. i wondered what would happen if i charged it and held it at 4.3vpc.

With the Motor running feature on my Superbrain 989, i set it to run at 4.3V at less than 1 amp. the chager will only put out 1 amp until it reaches the voltage, of which then it'll reduce current to keep the voltage. it works just like a normal lipo charger. I verified the voltage output, and it was precise, holding at 4.3v. the cell came from an old airplane pack that was in a crash. it was about 1100mah.

Anyway, at the end of the charge (which i watched very carefully), the cell puffed and was warm. i set it outside and waited. overnight, it shrank back to normal size. i measured the voltage and it was dead. 0 volts. Nada!

YOU CANNOT GET EXTRA VOLTAGE FROM A LIPO.

So, what puzzles me is, why match Lipo cells when you cannot get any extra voltage out of them? and its not like having IDENTICAL capacities is going to make a difference in racing. you're not going to pull that much amperage. AND you're not going to be using a lipo for its whole capacity in normal racing applications. in a stock buggy, i only use about 1000 mah in 5 minutes. with a 3800 Apogee, i could run all my qualifiers with one pack. and i'm definatly not going to feel the difference between matched pack and not.

The bottom line is, There WONT BE A VOLTAGE WAR anymore with lipo. Besides, the ROAR lipo rules state 8.4 volt lithiums only.
A matched pack (If possible) would be a safer and better balanced pack. It would charge up better and less time in balancing. Most of my Lipo's will balance out when charging is done already, so I don't see where matching will help much. But some idiot, with a lot of money to throw at something, will buy them
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Old 01-19-2008, 06:29 AM   #50
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When you can purchase a pair of packs that will last you for 2 years & running 2 or more classes for under $200 it will make things awsome.
They will have newer, better lipo cells out in two years, Your two year old batteries won't be quite as competitive, and you'll want to replace them. My Nimh batteries were good after two years, but there were not competitive with current technology two years later.

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The bottom line is, There WONT BE A VOLTAGE WAR anymore with lipo. Besides, the ROAR lipo rules state 8.4 volt lithiums only.
Sure there will be, an 8.499 volt battery is still a 8.4 volt lipo battery. Besides, its not just about peak voltage, its about voltage drop under load and how high the voltage stays up during discharge. Nimh batteries were matched according to their average discharge voltage, not peak charge voltage. There are other things like lower IR and higher capacity too. Longer races make those quailites in a battery more valuable.

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A matched pack (If possible) would be a safer and better balanced pack. It would charge up better and less time in balancing. Most of my Lipo's will balance out when charging is done already, so I don't see where matching will help much. But some idiot, with a lot of money to throw at something, will buy them
Matching between cells in a pack is common procedure this days and should be expected. Nobody has any gripes about cells in a pack being matched together. Its being able to compare the average discharge voltage, Internal resistance, and capacity between battery packs thats whats important. For instance, if you were purchasing 1 Orion 4800 pack at a hobby shop, and all the Orion 4800 batteries were labeled just like Nimh. One battery has 30 seconds more capacity, so its average discharge voltage is higher by .03 volt compared to the other batteries in the display case. Would you ask the guy behind the counter to pick out that one better battery from the case? If you were constantly finishing right behind first place in your races, would you let that slightly better battery go?

I'm not sure how long some of you have been racing r/c cars, but after racing for 24 years myself, Lipo will not be any different than Nicd/Nimh with exception to a higher price.
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Old 01-19-2008, 07:26 AM   #51
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A matched pack (If possible) would be a safer and better balanced pack. It would charge up better and less time in balancing. Most of my Lipo's will balance out when charging is done already, so I don't see where matching will help much. But some idiot, with a lot of money to throw at something, will buy them
I have owned 2 Apogee 3800's for almost a year now. I have NEVER balanced them, and they are still within .01v of each other. i charge at 2C (7.6A) al the time. The pack is not matched, yet it aparently doesnt need to be. matching a lipo is just not necissary, unless you're working with lower quality ones. All you have to do is make sure the cells are the same voltage. theres nothing more you can do.

Yet some people will buy things if you mention something useless or that is taken for granted. On TV, there was an Infiniti commercial, and it was advertising its car based on the differentials. NO DUH! every car in the world has differentials.

its funny how people will do this.
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Old 01-19-2008, 07:26 AM   #52
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Old 01-19-2008, 01:40 PM   #53
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I've also been racing since the 1980's

I think Lipo will indeed change things.

Yes, there are differences from one brand to the next.
Yes, there will certainly be improvements over time.
Yes, there might be a measurable difference in lipo packs on the LHS shelf.

It's about how consistent lipos are (matching cells isn't needed... cherry picking packs won't make a noticeable difference imo) and the customer's perception.

Like the saying goes... perception is reality... and when racers believe it doesn't matter, they won't get suckered into paying a premium like we always have with nickels.

I believe you could pick a dozen Orion 4800 packs (or about any other brand) and run them... and not tell any difference between any of them... even if a TurboMatcher shows it.
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