I am working on a project where I have various components connected to an Arduino Uno. These components are 2 LEDs, a keypad, buzzer, potentiometer, limit switch, LCD, and NO switch. In addition to these components I also am using 2 servo motors. My Arduino kit came with a 9V battery. I know that it is not enough to power the servo motors (I do not want to have it connected via USB to my computer).
I bought a 4 AA battery holder to plug into the breadboard. The leads were too small to fit in the breadboard so I soldered them to the jumper wires provided in my Arduino kit. To do this, I did strip about 1-1.5 inches of the battery wire holder which seemed to have a different material then the solid leads that were initially on the ends. I connected the red wire to the positive of the breadboard and the black wire to the negative. Then I also connected the Arduino ground to the ground of the breadboard. The problem I am having is that the batteries get VERY hot after about 15 minutes and I am not sure why. Is it because I stripped too much off the leads?
The original setup that I was using was plugging in the 9V battery to the barrel jack of the Arduino to power everything but the servo motors. Then I had the battery holder attached to the breadboard to power the servo motors. Since the AA batteries are overheating I am wondering if it would make sense to buy a AA battery holder with a barrel jack connector instead and have that as the sole power source for all my components and if this would be a better option to prevent overheating?
Essentially these are my questions:
1: Why do the 4 AA batteries overheat? (I even have a SPST switch hooked to the breadboard so its overheating even when there’s an open circuit)
2. Could I just buy a 4 AA battery holder to plug into the barrel jack of the Arduino Uno to power all my components? Would this option eliminate overheating since I wouldn’t need to solder?
3. 4 AA is what I read on an Arduino forum for a recommended amount. Is this too much? Could 2 AA batteries work as well?