The best specifications of power bank

Hi!
What are the best specifications of power bank to power a car project using arduino board?
The value of current and voltage of the battery.
Thank you.

What about the car power/battery?

Is the car going to be a road going car or a model car ?

srnet:
Is the car going to be a road going car or a model car ?

a model car,small car...a small project.

Idahowalker:
What about the car power/battery?

a car consists of 4 dc motors , two L298N ,ultrasonic sensor,servo motor,and other sensors
What are the appropriate values for current and voltage for the battery?
I want to buy one power bank.
Thank you for your reply.

What voltage do your motors need?

Add 3-4V to compensate for the losses in the L298N (or get a more modern H-bridge such as the TB6612FNG so you don't have to waste so much power), that's the voltage your battery should supply.

Then check the current your motors take (that's probably >90% of the power your car needs), and how long you want it to be able to run. That gives the minimum capacity your battery should have.

Without knowing the current being drawn by your device, I'd recommend something like this https://smile.amazon.com/gp/product/B06ZYRCPS3/ref=ox_sc_saved_title_2?smid=A646DVGSXYMNH&psc=1

kinda:
a model car,small car...a small project.

When you say 'power bank' do you mean one of the devices that people use to provide 5V of power to typical portable USB devices such as moblile phones, tablets and similar ?

Such a 'power bank' may not be able to provide enough voltage or current for a 'model car', but you have kept the details of the 'model car' secret so no-one can be sure.

A better power source for 'model cars' are Lithium Polymer batteries. Be aware however that they can put out very large amouts of current and can be a fire and explosion risk if not handled properly.