volts or amps wich is better to improve performance for my rc car?

have a 7.4 volt 5400mah lipo batt whats 11.1 gonna do should i worry bout mah with the 11.1 volt bat

seandogue8 years ago
There are only two types of performance I can think of off hand, speed/power, and duration.

If it's speed you're after, the increased voltage may or may not make a difference. regardless of problems it might or might not cause in the other circuitry to which it's connected, if the motor controller is self-regulating, it may attempt to compensate for the higher input voltage as well as for battery droop, and just burn out from dumping all the heat it dissipates dropping the excess voltage, and if not you may get increased speed but may burn out the motor by driving too much current thru its windings. Of course, since the car is 60 or 80 feet away from you when this overheating happens, you don't know until it's too late. (ime, having worked in test environments for nearly three decades, no-load bench testing only for conceptual preliminaries...testing under load is where the money's made and lost)

If it's duration you need, then the elevated voltage will only provide you with longer run time if

a) the weight of the new pack is equivalent to the old pack

b) a step-down regulator is used to convert the voltage to a usable value by the car's electronics, where the regulator is capable of delivering the maximum current required

c) the equivalent mAh rating exceeds the original PLUS any losses in the regulator stage and losses due to increased weight. (or gained by weight reduction)
lemonie8 years ago
And extra 50% voltage would drive the motor faster, and hotter. You'd be best using the 11.1 for the motor only and running the control-gear from a separate battery. But keep checking this with fingers & nose for overheating.

frollard8 years ago
replace it with another 7.4 volt battery. If you go higher voltage, you could fry the car. You might get some more juice to the motor, and you might get a speed increase by going higher voltage, but again - if the electronics aren't expecting nearly double the voltage, it will let out the magic smoke.

mah (milliamp hours) are a capacity. More mah = more run time, usually at the cost of being heavier.