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Old 11-08-2007, 03:08 PM   #31
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a lot of the mod guys will not want to make the switch to lipo because of the voltage. all mod drivers are running 6 cells at 6.0V. Lipos are 7.4V. It's mentally harder to put a slower motor in the car than it is to put 1 less cell.
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Old 11-08-2007, 03:36 PM   #32
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But for what I see here they have to switch to less powerful motor or they will not finish the 5 minutes with 5 cells, I do not see what is the point.
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Old 11-08-2007, 04:00 PM   #33
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Kn7671, I don't normally single out individuals, but you are an ignorant moron.

I hope you are not saying something positive about the nazi's occupation. It seems to me that a governing body needs to step in when a dangerous, obviously defective product is used in a hobby.

Further, you have cells blowing up several times a month at your club and you have a cavalier attitude about it. We'll see what happens when you or one of your friends is injured by the loveable IB cells.
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Old 11-08-2007, 04:24 PM   #34
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Kn7671, I don't normally single out individuals, but you are an ignorant moron.

I hope you are not saying something positive about the nazi's occupation. It seems to me that a governing body needs to step in when a dangerous, obviously defective product is used in a hobby.

Further, you have cells blowing up several times a month at your club and you have a cavalier attitude about it. We'll see what happens when you or one of your friends is injured by the loveable IB cells.

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Old 11-08-2007, 04:38 PM   #35
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But for what I see here they have to switch to less powerful motor or they will not finish the 5 minutes with 5 cells, I do not see what is the point.
The cell # has nothing to do with length of time. The capacity is still 4200. The differance is that they are on the throtle more.

I've seen about 5 packs blow up in the last little while. 4 were IB cells and one was an EP cell. All of them blew up because they were still in the battery cases. I had one blow up on me because I was charging it fully while it was in the car.

It is really bad when you blame a "matching" company for "making" bad cells.
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Old 11-08-2007, 04:49 PM   #36
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Hi guys

There seems to be some misunderstanding about what has happened in Norway the last few days.

The blown up battery pack picured at redrc.net is mine.
One more pack exploded during the raceweekend, and we measured more than 130degrees C on one more pack(Integy I think).

On monday I sent a mail to the Norwegian federation expressing my concerns for the safety of the drivers.
At that very weekend I understand EFRA had a meeting where Team Orion and LRP had expressed concernes regarding the IB4200 cells.
This in total lead to the decision of stopping all races sanctioned by the national federation.

The Federation has NOT banned club level activity, but have advised the clubs to temporarily stop their activities until investigations have been conducted to improve the safety of the drivers.

It is my understanding that most clubs here will allow regular activity but without IB4200 cells, and of course beeing more focused on not overcharging any other batteries.

I normally charge my batteries at 5A with 3mV deltapeak, and 43 degrees C tempcut for safety. I use a Team Orion Advantage charger.
When my pack exploded I had borrowed a charger (same charger) since my charger was busy with disharging the pack I raced with last to see how much was left.

I later discovered that this charger was set at 6A charge with 6mV deltapeak, still 43 degrees C cutoff. So this was obviously neglect on my part, which I do not refuse.
Still, the guy that own this charger charges his batteries in this way so this could still be next to me in a race...
As a sidenote, I later found a tech note in my pitcase, from a different manufacturer saying that the recommended charger settings for IB4200 cells are 6A charge and 5mV deltapeak.

The other pack that blew up (LRP) was charged at 5,5A but I don't know the deltapeak setting.

I was listening to music while getting my car ready for the last final.
When I removed my headset I heard a fizzing noise and looked at my battery. Smoke was gushing out from one cell and I immediately shut the lid on the case with the charger. '
Then I realized that there were three more chargers, probably with batteries connected, in this case...
I opened the lid and pulled out the battery. Fortunately I was sitting at the rearmost row in the pit, with about 10m to the back wall.
I threw the battery along the floor over to the back wall. From then it was a matter of 3-5 seconds before the blast. And yes, this is a blast. Similar to a shotgun blast.

If that thing had blown up in my face I'm sure I would have been blind today. Fingers would have been lost if it had gone of when I held it.

Last edited by OleC; 11-08-2007 at 04:59 PM.
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Old 11-08-2007, 04:52 PM   #37
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All electric activities are baned here
Wow, I stand corrected, but how can they have the authority to ban it all!

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Old 11-08-2007, 04:53 PM   #38
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Most of the drivers in Norway think that this is an overraction by the federation here and an abuse of power
John, posting your oppinions as the views of "most drivers in Norway" is just BS. Please don't...


@skiddins: The federation have NOT banned all racing, but advised a halt pending the investigation of what can be done to improve safety. As I understand, most clubs allow practicing as normal, but some will bann IB4200 for the time beeing, and promote charger settings "on the safe side" ie 1C rate and low deltapeak.
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Old 11-08-2007, 05:10 PM   #39
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Man I wish EP cells where open to the public I would be buying mucho sharesthe death of IB and I'm sure lipo will come to the funeral to pay it's respected
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Old 11-08-2007, 05:22 PM   #40
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a lot of the mod guys will not want to make the switch to lipo because of the voltage. all mod drivers are running 6 cells at 6.0V. Lipos are 7.4V. It's mentally harder to put a slower motor in the car than it is to put 1 less cell.

This is incorrect. A single normal NiMh sub-c puts out 1.2V, so 6x of these in a pack 7.2V. I think what you meant was mod drivers are running 5-cell, which is 6.0V.
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Old 11-08-2007, 05:33 PM   #41
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Kn7671, I don't normally single out individuals, but you are an ignorant moron.

I hope you are not saying something positive about the nazi's occupation. It seems to me that a governing body needs to step in when a dangerous, obviously defective product is used in a hobby.

Further, you have cells blowing up several times a month at your club and you have a cavalier attitude about it. We'll see what happens when you or one of your friends is injured by the loveable IB cells.
Yo Bill, not what I meant at all. I just hate to see people overly protective of a problem that has been well discussed as a known issue with the IB4200's, and then to see santioned race events suspended because of it is crazy. They could have easily said that batteries must be charged inside some sort of container to prevent potential injury until more testing can be done to create a new battery approved list.

I liken this to people forcing helmet laws on motorcyclists. We all know of the inherent danger of not wearing helmets, but we don't need people telling or worse, stopping us from riding w/o one.
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Old 11-08-2007, 05:48 PM   #42
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Originally Posted by POUNDITRACING View Post
a lot of the mod guys will not want to make the switch to lipo because of the voltage. all mod drivers are running 6 cells at 6.0V. Lipos are 7.4V. It's mentally harder to put a slower motor in the car than it is to put 1 less cell.
This is not an attack on you, or your intellect, but that's the goofiest thing if ever read. I think the lack mental ability to run a slower motor has got to be an extension of "small pennis syndrome".

I havn't jumped ship just yet (onto the lipo boat), but this whole 5 cells is the answer thing is just retarted. Seems to me that running a lipo with a "mild" motor would be the way to go. Unless of course you are vested in a Sub-c company.
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Old 11-08-2007, 05:57 PM   #43
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A motorcycle helmet is a poor analogy because if a rider chooses not to wear a helmet and they get into an accident, what about:
1) their family if they suffer brain damage or death
2) insurance rates because their brain damage will cost a lot of $
3) the other driver in a collision who will be sued for many times the damages than if a helmet was worn,
4) etc.
Your actions affect much more than is obvious.

In terms of norway, I know that is not what you meant. But like some other things, you never want to make light of nazi's. But for a few small details during WWII, the world today would have been much different, many of us would not be alive, and the USA would not exist. You have to be careful about how your remarks come across.

In terms of IB cells, remember this is a hobby full of dangerous things. Most chemicals in this hobby take time to do harm, an exploding battery can do harm instantly. R/C racers already do many dangerous things, playing with small granades is not wise. Taking precautions and stopping an activity to make it safer is smart, that is the role of a responsible governing body.
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Old 11-08-2007, 06:06 PM   #44
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The cell # has nothing to do with length of time. The capacity is still 4200. The differance is that they are on the throtle more.
How is that? It would be true if the cars were slower. But they are faster. To be fast they need watts. watts come from the product of volts x amps.(in simple terms)

For example if you have a car with 1500gr and 375w with 7,2v you will put out from the batteries 52A (375w/7,2v=52A)

If you would like to have a car with 5 cells that is as fast you will need the same power to weight ratio as the other (250w/kg). So for a 1430gr car you will need 357,5watts. this time with 6v you will need to pull from batteries 59,5A
(357,5w/6v=59,5A).

That is why with the same batteries you will have less time to drive. With 6 cells you pull 52A with 5 you will pull 59,5A.

If you aply the formula that relates time with the batteries capacity and currente drawn you have Time(minutes)= Capacity(in amp)x60/discharge rate(amp)

That makes T=4,2(4200mah)x60/52 that makes T=4,84minutes (for 6 cells)

With 5 cells, T=4,2x60/59,5 that makes T=4,23minutes.

These are just invented numbers this is not the real thing but I hpoe I can help understand the stupidity of using 5 cells, at least at big tracks.
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Old 11-08-2007, 06:17 PM   #45
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mrrcguy I agree with you, the lipos and softer motors.

To add on that we know a 3200mah cell will make the same track time as the 4200Mimh just because they are much more efficient. so that means our cars will be lighter and we will need less watts to drive them fast so with that 3200lipo we will drive longer that with the Nimh (if we can have the car lighter by the rules)

Now imagine we ran 5000mah lipo, we can make mod races for 10 minutes. The cars can be lighter so less stress on the mechanics, easier to drive... Nice, no?
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