> I fully agree that some manufacturers (cough Apple) are obsessed with thinness, but I strongly believe the main driver behind fixed batteries is planned obsol

> I fully agree that some manufacturers (cough Apple) are obsessed with thinness, but I strongly believe the main driver behind fixed batteries is planned obsolescence. i've worked with companies making the kinds of products you're concerned about. this never comes up. they are however terrified about lithium batteries in consumer products catching fire, and want to keep you, the user, far away from them. thin flat batteries also tend to stay a bit cooler, which helps in multiple ways.