Thanks Nick.
Think I will have to use them in the new MiniMower.

Were up against it for weight and space.

Rob wont compromise on weapon motor, Armour and reversible drum rotation and I don’t wont to lighten of the drum so something has to go.

Thinking separate drive and weapon pack.
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Satisfaction is proportional to effort and results.

Its your call, but a single larger pack is more weight efficient and usually a bit cheaper per AH. You only need one set of wiring and one power switch, so unless you need to run significantly different voltages for weapon & motor, I would go with just one big pack.

Good point, when I have a little more faith in LiPo’s maybe.

It’s just with this particular bot I can just have one switch between the 2 battery negatives and the common earth buss.

Thinking along the lines of charging the drive battery in the bot between fights and swapping the weapon battery and taking longer to charge it as potentially as in a fight with Rhino it could be hot and flat.

So 3 small batteries vs. 2 larger ones.

Also they are so light compared to what I am use to its not a problem weight wise, the packaging works better in this particular bot and if a battery gets destroyed by physical or overload individually they are cheaper than a larger one.

The Kkeerroo’s bot at the last Battelshed went a long way to convincing me they were worth a try.
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Satisfaction is proportional to effort and results.

could i run two a123 packs with one pack running esc and both running weapon? like both packs in series and one pack has esc jumped off it?
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Tim Team Reaper.

you should be fine as long as you charge them both individually and keep them all balanced.

youd probably be better using a little lipoly for the drive though to be lighter and smaller
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

it'll be fine, just charge them separately.
use a balancer on each pack too.

just make sure you don't over draw the drive pack
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Mechanical engineers build weapons, civil engineers build targets

prob be using a scorpian controller i think they have voltage cut off.
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Tim Team Reaper.

Robot Marketplace has just added balancing connectors to their build your own A123 packs . The balance tabs only add an extra $3 to the whole pack, so well worth it.
I've been using their packs for a while now and not had any problems (granted I'm using them on 100W scooters).

They are charging $111US + freight (~$159AU at 70c) for a 6 cell A123 pack (19.2-21.6V, suitable for DSE 18V drills) assembled with balance connectors. That works out at around $18.5US per cell (~$26.50AU at 70c)

Not bad saves the pain in the assage of soldering and killing a cell or two.
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Tim Team Reaper.

http://www.gizmag.com/obama-battery-vehicle-industry-investment/12457/
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Satisfaction is proportional to effort and results.

hehhe still makes me laugh that they are not even as good as the current direct injection VW Jetta in terms of carbon footprint or thermal efficiency.

still a ways to go yet ole hybrids.
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

http://www.popsci.com.au/cars/article/2009-08/ddr%e2%80%99s-finest-auto-gets-makeover


I am really not primarily interested in electric cars, amusing as it can be.

I am more concerned that all this money being spent on new battery technology might actually produce something that will work in our bots.

Then I will have to spend more money just to keep up again.

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Satisfaction is proportional to effort and results.

I have 2 li-po packs 7.2 volts 4000mah 25c discharge rate I use in my rc brushless car. In your opinion would they have the power to handle running 2 drill drives and a brushless motor for a round without killing the batterys?.

There is quite a wide range of brushless motors out there, but it would take a continuous draw of 80 amps to run down a 4000Mah battery in 3 minutes, and you would need quite a large brushless motor to accomplish that. so you should be fine.

Here's a helpful excel document I found on the internet previously, its helps a lot with this problem:

http://www.rcgroups.com/forums/showthread.php?t=703489
its attached to the third post down, and called "time vs current"

awesome thanks for that.