The host of the Phone Repair Guru YouTube channel in one of the issues checked whether the iPhone would work if you connected AA batteries instead of a battery. The result surprised the author.
The old iPhone 7 Plus was taken as a basis, andThree AA batteries acted as a power source. Oddly enough, the iPhone, after connecting ordinary AA batteries to it, began to work, but it was unstable. The device began to turn on and off due to lack of voltage.
You can watch the video here: YouTube Shorts