How would you spend £500?

[Max]

Personally I would buy some large capacity SLAs as they are cheap, not much an go wrong, and will provide a much longer running time which for a group of students, I think is important as they don't want to have 3 mins of driving before having to stop and wait for am hour to charge.
You could however just get larg capacity NIMHs but those would be expensive.

[PJ-27]

I wouldn't run smaller cells in series, just more packs to charge.

[Ellis]

NiMH batteries are expensive for their performance. For the best run time/cost/power output ratio for this you're probably best looking into SLA. A typical car charger should charge them, too, which saves money on needing a fancy charger to do the job.

Granted they weren't off the shelf, but the two 2.5Ah 18v NiMH packs Component-Shop made for us cost more than 60 quid undelivered. You can get a far superior LiPo in terms of power to weight for much less.

Though LiPo charging brings its own risks, understandably, so I'd return to thinking about SLAs. Scotbots use them, and from what I can tell, they work well for them.

[Bodge Job]

I have used Slas for ages, and they work well. and as a bonus you pretty much treat them awfully and there still fine. And you cant damage them from Discharging at a to high current because they simply wont give out more than they can handle, which also means they save stalled motors!

But how ever unlike other batteries, the AH changes depending on the current you discharge at, so you need a high AH for higher currents but for your application 7Ah would last many many battles. Bruiser would last all day on one!

[typhoon_driver]

For students, SLAs. For a combat machine, lipo

[Dan-27]

Have people any experience of these ESC's?

http://cgi.ebay.co.uk/ws/eBayISAPI.d...:X:RTQ:GB:1123

They've said I can have 12 for £140 saving about £15. Because of the low voltage of the kits these seem ideal, just wanted to check and see if anyone had experience with them, specifically if they'll have the same mixing issues as the TZ85a's?

[maddox10]

I hope the dimensions are wrong. Also. With 14awg wires and 320 amps... Then the wire acts as a fuse.

[plargen]

i use them in both my bots on a 4s lipo after a battle the motors are warm but the esc are still cool

[Danjr1]

specifically if they'll have the same mixing issues as the TZ85a's?

I THINK I've cracked the mixing issue but I'll confirm hopefully by the end of the week. Seems to work on the bench anyway but I need to give the code a +3 minute run in a bot to confirm that the mixing works and the temperature cut out has been disabled.

[Dan-27]

I hope the dimensions are wrong.

Good point I hadn't spotted that they're a foot and a half long! I'm hoping it's a translation error.

Great news Danjr1, I'm going to be using TZ85a's in at least one maybe two of them so keep us posted on your progress. As these are half the price and I don't need more than 12v I think I'll go with these.