Arduino portable soldering station

Heyyy, i made this soldering station to be compatible either with drill batteries or laptop psu (everything 15-24v). The temperature can be set with the 2 buttons and by pressing them simultaneously it displays the percentage of the baterry and when the battery is low it starts blinking. There's also a protection from broken cable or heater problem so it won't overheat. The temperature can be precisely calibrated via the potentiometer. I used lm358 but there're better options out there with lower offset. For improvements the linear regulator can be changed with a buck converter and a buzzer can be added to indicate better the low battery and the mosfet should be a logic level one like irflz44. Forgot to mention that the temp is PID controlled and the PID values for stability can be set in the code