Mini 5V board for 2S or 1S


I need to replace the NiCd battery from my kids rc car to a 2S lipo. Easier to charge and better mah capacity.
But the car is rated at 4.8V. So i was thinking to use a 5V voltage regulated board.
My choices
1S + voltage boost 5V
2S + Voltage drop 5V

What do you think ?
Do you have any good link on fasttech ? for exemple?

Hah. You dont need any voltage drop for dc motor. Just buy any 2s pack.
I cant give any link because I dont know battery place size.

No because 2s is 8.4v to 6.6v way higher than nominal 4.8v

dc motor has very small probability to die from bigger voltage.
(I hate low rpm screwdrivers, so my bosch ixo is powered by 2x18350 instead of 1x18650).

Sometimes I use a big rectifier or diodes to drop voltage of a battery pack

yes Lexel i was thinking of using 4 big diodes 8.4 –2.8 = 5.6V
should be fine and current should not be so big for that type of car.

I’m no talking about a brushless motor + bigESC…here that’s a 4 parallel NICD crap battery pack and i want to use a small 1200mah 2S lipo. I have a ton of them for my FPV drones…

I'm with kiriba-ru on this one, 50% extra voltage and current (rpm and torque) means up to 225% power output. Of course I don't know what kind of speed controller the stuff uses, improve it if required. Your kid will love it!

You'll need pretty beefy diodes otherwise (20+A) or they may die.

Cheers ^:)

P.S.: upgraded my 2S AA Ni-MH hairclipper months ago with a 1S2P 14500 high discharge li-ion set, and I am very happy.

Voltage to the motors should be fine for 2S, but unless the electronic parts are rated for >8V, I’d drop in a small 78L05 or similar 5V regulator to just those parts (eg, controller board).

NiCd runs flat 4.8V ’til it’s on its last gasps for air, then drops like a rock. Great source of semi-regulated DC from freshly-charged to dead. So you can run 5V ICs, µCs, etc., from a 4.8V pack quite nicely, right off the rails. Hitting ’em with 8V might very well fry ’em.

Motors, though? They’re quite happy with some overvoltage, especially if you’re running ’em at partial power 99% of the time anyway.

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