Depending on the internal design of the phone, maybe.
But batteries are rectangular and they can’t put them EVERYWHERE. There are places (such as near the USB port) where you can’t really put battery no matter what because there have to be things that would interfere with the rectangular battery.
So it might have an effect, but not necessarily, depending on design, and it might be smaller than you’d think.
Depending on the internal design of the phone, maybe.
But batteries are rectangular and they can’t put them EVERYWHERE. There are places (such as near the USB port) where you can’t really put battery no matter what because there have to be things that would interfere with the rectangular battery.
So it might have an effect, but not necessarily, depending on design, and it might be smaller than you’d think.