Power Supply Guidance for UNO R3, L298N Motor Controller and ESP8266-12E

My project is using the following components:

My objective is to be able to control this robot via WiFi through the ESP 8266. I have successfully connected the UNO and the L298N to a 6V battery pack. I have connected the UNO's D6, D7, D8 and D9 to the L298N's IN1, IN2, IN3 and IN4 pins respectively. The D5 and D10 pins on the UNO are connected to the DC motor jumper pins. The positive power from the battery pack is connected to the L298N power pin. Both the ground for the battery pack and the ground for the UNO are connected to the L298N ground pin. The 5V pin on the UNO is connected to the 5V output on the L298N. This configuration works fine for autonomously programming the robot.

I will be connecting the ESP8266 to the UNO via serial communication. What is the best way to power the ESP8266 with the other modules. Should I increase the size of the battery pack or use a separate pack?

The ESP8266 is a 3V3 system so you will need a logic level converter between the two serial lines going to the Uno.

The best way to power the ESP8266 is to connect the 6V battery pack to the Vin connector of the ESP8266. There is no need to add extra battery capacity as the ESP8266 will take little current.

Grumpy_Mike: The best way to power the ESP8266 is to connect the 6V battery pack to the Vin connector of the ESP8266. There is no need to add extra battery capacity as the ESP8266 will take little current.

On some, maybe all, variants of the ESP8266/NodeMCU boards the Vin pin is directly connected to the USB connector 5 V pin, so it might be safer to use the regulated 5V from the L298 module to supply the ESP8266 Vin. If 6V from the battery pack is used, take care to disconnect battery before plugging something into the ESP8266 board's USB port.

That worked! Thanks for the help!