Speed problems

hi everyone

i wonder whether anyone could help me, i recently replaced a 12v sealed lead battery for two 7.2v nicad ones. but i dont seem to get any improvement in speed from them and they are going even slower than with the sealed lead in. i have worked out it is the batteries or the wiring attached to them because i put back the sealed lead to check and it was wizzing around like it did. so what to do?

hope this makes sense and someone can help!

thanks alex}}

Alex you need volts to get speed (amps for capacity). By replacing your 12v batteries with 7v batteries you will have almost halved your speed. Im afraid there isnt any easy way around this - sounds like youve bought the wrong thing.

What Nicads will bring you is a lower weight for the same capacity however lower voltage means a lower speed - thats physics for you Im afraid

Ed

Alex have you wired up your Two 7.2v Batteries in Series mate? This will give you 14.4v which will make it a bit faster than your 12v battery, though not too much difference, just you will save alot of weight.
Have a quick look here mate - http://www.stupoo2000.pwp.blueyonder.co.uk/teamkat/batteries.htmhttp://www.stupoo2000.pwp.blueyonder.../batteries.htm
You want to wire your Two 7.2v Battreies the same as the first diagram on that page.

Mr Stu

Lets try the blindingly obvious first FLAT batteries?
Next.......
How have you connected the 7.2v batteries.... in parallel or series?

I.E.
Positive of both 7.2v batteries connected together and both negative.... then connected to your controller. PARALLEL

Or positive of one 7.2v battery connected to the negative of the other 7.2v battery........the remaining 2 leads ( a positive and a negative ) connected to your controller. SERIES
PARALLEL gives you 7.2v.

Tsk ......Beaten to it...
Seems my post is superflous....:sad:
SERIES is the correct way to get 14.4v.

(Message edited by woody on March 16, 2006)

Also, if an battery is of a low qualtity it will have a high internal resistance, and that means it cant kick out the amps to get up to speed.

If this is the case, your batteries wont live long.

thanks for the help

alex