battery type

**lewisantweight** · 14th April 2012, 20:16

I have all the components for my robot:
sabertooth speed controller
24v motors
armour and weapon
transmitter/reciever and the rest but i am not sure what type of battery works best? It would be great to know so i can get the right ones.

**mattsdragons** · 14th April 2012, 20:32

Any battery type really

Low end stuff is really SLA's

Mid range (the most common seen) is Nimih

Top end is realy A123 packs and lipos

That's just what I see, but go for Nimh as you can't really go wrong

**typhoon_driver** · 14th April 2012, 20:35

Yup go for nimh. Search on ebay for component shop and buy a couple of their 3300mAh Nimh packs in whatever voltage you require. Simple batteries and very easy to look after

**lewisantweight** · 15th April 2012, 18:38

i have 24v motors and a sabretooth esc so how many volts do i need , the full 24 or less.

**beast** · 15th April 2012, 19:01

all depends how much money u want to spend and what charger u have but theres lots of people going just for 14.7 volts its the amps which make it last longer ie 2.2amps or 5 amps our beauty/rip ran on a 14.6v 2.2 amps runs very nice does 3 fights as well (just)

**maddox10** · 16th April 2012, 04:04

Originally Posted by lewisantweight

i have 24v motors and a sabretooth esc so how many volts do i need , the full 24 or less.

Your 24V motors will run on less. Electric motors have an RPM per V rating.
That is exactly what a speedo does.
Shopping up the electricity in bits, and only feed as much bits to the motors as the controller is instructed to do. Limiting RPM, and therefor speed.

So, using a 12V battery, and a speedo on those 24V motors will have 2 results.

Top RPM given by the motor manufactorer is halved. And with half volts, the amps drawn is halved too. Meaning a motor of 400W will deliver only 100W.

The other way around is also possible, feeding a 12V motor 24V will double speed, and quadruple power.

Unfortunatly, there is a penalty there. A good brushed motor will do 75-80% efficiency. Meaning 20-25% of the power isn't converterd to movement, but to heat. A 12V 100W motor will make 20-25W of heat- a soldering iron-. The same motor on 24V will draw up to 400W and make 100W of heat.
Now, with the basic premisse, that ain't a problem, as the original motor was a 24V motor, and that can dissapate those 100W of heat.

**lewisantweight** · 16th April 2012, 09:54

ok thanks that was interesting it helped alot.

**Max** · 16th April 2012, 10:30

I don't think it is a good idea running a sabertooth (depending on which one it is) off 24v as people say don't push that controller to its limits or it will blow up.