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Old 10-25-2007, 10:01 AM   #91
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Quote:
Originally Posted by ROV View Post
bold makes no sence to me.


How about you come back to the LIPO question thread when you run a a123 7.4v then you got somthing to compare,mah is no substitute for volts. 101 understanding DC
totally agree with ya man! ^^^^^^^^^^^^^^^

your saying its lighter than lipo but near same weight as sub c? wtf?

voltage = speed, mah = run time. having more run time doesnt mean anything really. look at mod guys, they run like 3300mah packs in onroad and they have plenty of juice left over. also they use 5 cell now, so thats 6.0v only, but because they use brushless its fine. but thats just mod guys, what about normal stock racers n such? in stock i use maybe just over 2000mah per race, but its the voltage and speed which gets me the higher placings. its only a 5min race, u dont need to last forever, u want PUNCH and SPEED.

so whats the point of having a LOWER voltage pack with HIGHER runtime? pfft, nothing

even though lipo is only .2v more i noticed a big difference in punch and a bit more top end speed. so 6.6v to 7.4v is a fairly BIG step then and a BIG difference.

all agreed? for bashing you want long run time, sure. i get like 30min outta like pack, thats PLENTY enough
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Old 10-25-2007, 10:51 AM   #92
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If your running stock then stick to 6cell stick. However the future of electric is li//bl(yes, a123 cells are race legal at the li//bl truck classes). First off I don't have any true tests while discharging them at that level. However I have run a mamba 7700 system w/out any glitching at all and tons of power. You can also pick up a bec if you think you might have issues. The simple reason I run them is that they are a safer cell w/ tons of power and you can always find a bigger motor.
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Old 10-25-2007, 11:20 AM   #93
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Sorry but i need serius proof of a123 is more safe than the popular lipo

The new lipo cell was certified CE UL and pass multiple test

over charge to 12V
over discharge to 0V
puncture

check the a123 site web i never see anything about the safety
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Old 10-25-2007, 11:54 AM   #94
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A guy at our track runs the a123 batteries. He slammed a wall and the battery came flying out smacking the wall as well and nothing happened to it. He ran it in the main about an hour later and it still had good punch and run time.
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Old 10-25-2007, 11:59 AM   #95
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I checked it out and here you go.

http://www.a123systems.com/newsite/i...nology/safety/

Quote:
Originally Posted by dgaumond View Post
Sorry but i need serius proof of a123 is more safe than the popular lipo

The new lipo cell was certified CE UL and pass multiple test

over charge to 12V
over discharge to 0V
puncture

check the a123 site web i never see anything about the safety
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Old 10-25-2007, 12:04 PM   #96
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Heres a quick video of what happens when the a123 cells are punctured.
Oh yeah, they have been certified safe for automobile use. Not to mention when they build up too much pressure the caps will release it instead of turning into a bomb. The cells still typically work when they are over charged or discharged, however they will show signs of abuse. In an aplication such as 1/10th scale 4wd where a car may ram you in the side while you take a sharp turn that could damage an encased lipo or a123 cell I would rather see a cell let out a few fumes then go up in flames. Not to mention you can build a 4600 mah 6.6 volt saddle pack for under $50. I wonder how much that orion pack will set people back.
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Old 10-25-2007, 12:30 PM   #97
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Part wagon you must really like these cells. shoot me the links fo the $50 pack please and I will give em a shot.

Quote:
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Heres a quick video of what happens when the a123 cells are punctured.
Oh yeah, they have been certified safe for automobile use. Not to mention when they build up too much pressure the caps will release it instead of turning into a bomb. The cells still typically work when they are over charged or discharged, however they will show signs of abuse. In an aplication such as 1/10th scale 4wd where a car may ram you in the side while you take a sharp turn that could damage an encased lipo or a123 cell I would rather see a cell let out a few fumes then go up in flames. Not to mention you can build a 4600 mah 6.6 volt saddle pack for under $50. I wonder how much that orion pack will set people back.
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Old 10-25-2007, 02:52 PM   #98
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You can find most of this info w/ google and a little common sense.

I purchased a dewalt 36volt pack, made out of 10 a123 cells for like $80 and used 6 of them to make my pack.
You can find them on ebay for around that price. Anything under $100 shipped is normally a decent price. If you are looking for a
2s2p pack for 4wd buggy then you could just split the cost w/ a friend.
Be sure to do your research on these cells before you take apart the pack. There are sites on breaking them down. The two pieces of information you will need though are to leave the tabs that come w/ the cells on them, just cut them if you want to take them apart or leave them togather instead of using battery bars, because you can't solder directly to the cells so you solder to the tabs & do not twist the tab, twisting it can cause the cells to dead short. Do not cover the little blimish w/ solder, that is how the cells vent.

How to build a saddle pack:
required
*4cells,3 long pieces of wire, two battery bars, plug,shrink rap
All soldering will be done on the tabs & will not be over the small blemish in the middle of the cells.
1.take two cells and solder the + to the - using a battery bar(this will be side 1, repeat w/ the other two cells.(side 2)(the more you wire + to - the greater your voltage)
2. take a piece of wire that reaches across the chasis and connect the wire to the + of (side 2) to the + of (side1).
3. repeat this process for the neg.
4. repeat this process again, you can use a lighter piece of wire for this(balancing plug), with the side the battery bars on on. Run it from battery bar to battery bar.
5. Now remove the rubber off the + wire in the middle for your plug. and solder the plug to it there.
6. repeat step 5 for the neg.
(don't let the + and - wires touch, these are just like any other +&- wires on a 6cell stick.)
Now take the 3rd wire and stick a FEMALE PLUG ON IT(you want to make sure that the wires are not going to dead short when they touch since you have an extra wire. Often times I zip tie the two plugs away from each other on the car.
7. shrink wrap the cells if you want too.

For building 3p2s pack(perfect for 2wd truck or buggy), you will have to lower the sides of the battery trey just use a cheap solding iron and melt the sides down, much easier then dremeling them down. You can see what i'm talking about at
thedunemaster.com (more of those expensive packs)
1. zip tie 3 cells togather w/ the + ends all facing the same way.
2. strip down a nice thick wire and use it as a battery bar to connect the 3 cells + side.
3. repeat for the - side.
4. repeat steps 1,2,&3 w/ the other 3 cells.
5. take a wire and solder the + side of pack 1 to the -side of pack two.(short wire) and another longer wire from any of the cells in the middle(balancing plug).
then bend the wire connecting the sides so that the cells make a straight line.
6. run a wire from the free sides to your plug.
7. Now shrink rap it.
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Old 10-25-2007, 03:42 PM   #99
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start a thread dude
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