My Sharp MM10 had swappable batteries: one was thin (total 0.54 inches for the laptop), and another would protrude out the back, but provided 8 hours of work.

My Sharp MM10 had swappable batteries: one was thin (total 0.54 inches for the laptop), and another would protrude out the back, but provided 8 hours of work. Not bad for 2003. https://www.wired.com/2008/01/sharp-actius-mm/ https://www.wired.com/2008/01/sharp-actius-mm/