I have two 8-15v dc motors. I would like to control them with the L293d. I have tried the normal 9v batteries, but they don’t provide enough power. What batteries would be the best choice?
The sort of batteries that provide enough current for your motors (check the motor specs) for as long as you want to run them.
Use 18650 batteries, these can deliver the amperage you need. Use a battery pack of the desire voltage you need.
A 6xAA battery pack is usually good for a couple of small brushed DC motors, especially when considering that almost half the battery power is typically lost in the antique, extremely inefficient L293D motor driver.
For more information, post a link to the product page or data sheet for the motors.
I have two 8-15v dc motors.
A lot depends on the size and current draw of the motor.