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A123 cells
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Fast5sRevo88
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A123 cells - 03.07.2008, 03:16 PM

What is an A123 cell? r they more powerful than a Li-Po? And will any speed control support them? (i have a monster pro)
   
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legobrains
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03.07.2008, 04:17 PM

Speed controls support a certain number of volts. It does not care if these volts come from a lipo, a A123 cell., or a hamster running in a cage.

The monster pro will work with A123 cells. It should handle 6 of them very nicely. However is has trouble with 6 lipos, because lipo have a bit more volts per cell.

You must have a A123 charger to charge them.

usually people buy them on ebay for around $100 shipped for a dewalt pack, see here to take a part and stuff:
http://www.rcgroups.com/forums/showthread.php?t=587606
http://www.rcgroups.com/forums/showthread.php?t=599316


Now, when you freshly charge a lipo, they are 3.7 volts per cell.
A123 when freshly charged are 3.3 volts per cell.

So they are less powerful then a lipo. They are also heavier for their power to strength ratio.

(1) A123 cell is a little bit bigger then a C sized battery.

A123 are not as volatile to explosion, they can also charge at a higher "C" rating. You could charge a A123 pack in 15 min



See this post on some more ideas for A123 and it has a picture of them:
http://www.rc-monster.com/forum/showthread.php?t=9397

Last edited by legobrains; 03.07.2008 at 04:23 PM.
   
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chilledoutuk
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03.07.2008, 09:03 PM

just to note a lipo has a freshly charged voltage of 4.2v and pretty much holds that if the cells are high quality even after resting.

A123 cells are charged to 3.6v per a cell but they tend to sag back down quite a bit to just over 3.3v after being left to rest after a charge.
   
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legobrains
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03.07.2008, 09:42 PM

One more thing, supposedly A123 cell have a much longer life span. They can take about 1000 cycles where as lipos can take about 100-200. (At least in the heli world that what their useful life span is.)
   
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suicideneil
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03.07.2008, 09:42 PM

More info: A123 cells are best ran in a 2p configuration for typical MT use (emaxx), though for a high voltage/low amp draw setup they work fine in a 1p layout.
   
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tashpop
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03.07.2008, 10:23 PM

i think a123's are the perfect answer for bashers. abuse and use. they're cheaper per power than lipo, and no need for a lvc either since they drop voltage hard when they dump. you'll know instantly when you're run is over.

lipo is better for a racer. lighter per power. capacity and volt. need to take better care of both charging discharging, and avoiding punctures.

compairing voltage setups, a123's run just alittle under lipo per cell as already pointed out. they basically match up 6/5 ratio a123/lipo. if you have an esc that'll handle 5 cell lipo, you can run 6 cell a123. 10 cell lipo run 12 cell a123. if you configure you're packs in 6s packs you can fully charge 123's with a 5s lipo charger. other wise its best to use an a123 adapter, or charge made for them.


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othello
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03.07.2008, 10:33 PM

My findings running them in a 11lbs truggy as 10s1p. For short bursts they are able of 100-120A giving you around 250 Watt per cell.


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