Best way to power up 2 DC motors, bt module and arduino

Hey everyone

I'm trying to figure out the best way to power up 2 DC motors (28BYJ-48 + ULN2003 driver), a bluetooth module (HC-06) and an Arduino Uno board R3.

I was thinking about powering them up separately, using 4x alkaline AA batteries for the board and the BT module, as for the two motors I'd also use 4x alkaline AA batteries. I think the former would work just fine, while the latter wouldn't last long. Should I use a LiPo battery to power everything together?

Is there a way to power both motors using 1.5 AA batteries and have it work for a decent ammount of time?

4x alkaline AA batteries for the board

What board?

Those are stepper motors. Stepper motors are not the best choice for use with batteries. How are the motors used? Is there a reason that they have to be steppers?

groundFungus:
What board?

Those are stepper motors. Stepper motors are not the best choice for use with batteries. How are the motors used? Is there a reason that they have to be steppers?

Arduino Uno R3 (Tmega328).
They have to be stepper motors because I need "high precision", they're supposed to behave in a similar way to this: CUBETTO PLAYSET by Primo Toys. Quick Overview - YouTube

Probably it would be best to use 9V rechargeable batteries or you could use those 4 AA batteries in series. If you have an old PC power supply you could use their 12V output since the Arduino board lets you do that. Also, you could buy a 9V wall adapter if you don't need it to be portable.

Amazon.com: Adaptador compatible de la fuente de alimentación de 9V 1A Arduino 110V AC: Home Audio & Theater

Describe "decent amount of time" in minutes or hours ?

If it is hours and it has to be battery then a decent size rechargeable battery would be a much better choice.

That small stepper only uses 100mA per phase @5V, and is typically driven 2 phases as a time,
so 200mA is the maximum current draw for it - the losses in the ULN2003 may reduce this
somewhat, so that I’d expect <= 200mA even at 6V.

Now you can add in the current taken by the rest of the circuit and calculate the required
battery capacities (then double that figure to allow for aging effects of batteries, which are
non-ideal components to say the least!).

So 6V 2Ah pack of AA’s would give about 10 hours max for the motor, 5 hours being a
more conservative rating.

An alternative to using two separate battery packs is to use a boost-buck DC-DC converter
to derive a separate 5V rail from the motor battery, being relatively immune to voltage
spikes and drop-outs caused by the motor switching.

You can use larger batteries also. 3 C-cells or 3 D-cells would last a decent amount of time as they have much higher mAH capacity than AA cells.

Or use some kind of Li based battery and a 5V step down regulator to supply 5V to everything.
Li ion, Li Po (polymer), Li Fe O4 (Li Iron Phosphate. You can find them with very high mAH ratings.
Google 6000 mAH battery pack for example.

Pololu carries a line step down voltage regulators in different current capabilities

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