Re:Ask HN: Who is building credit card size tracker using U1...
by kube-system on Monday September 12, 2022 @01:13PM
(#32813368)
The easiest way to charge something thin would be a proprietary pogo-pin adapter and pads.
Protecting it would certainly be a challenge. If I were to try, my first attempt would be to sandwich it between two sheets of stainless. (0.76-0.4)/2 only leaves .18mm left over... that's 33 gauge. Maybe too thin to add enough rigidity? If you used 28 gauge stainless that would bring the sandwich to 1.04mm, which might be a better compromise.
It would certainly need some prototyping.
Apple gets 1 year of battery life from 225mah. So, it seems reasonable to get a month from 30mah. Not great, but hey, we're just entertaining the packaging requirement.
Protecting it would certainly be a challenge. If I were to try, my first attempt would be to sandwich it between two sheets of stainless. (0.76-0.4)/2 only leaves .18mm left over... that's 33 gauge. Maybe too thin to add enough rigidity? If you used 28 gauge stainless that would bring the sandwich to 1.04mm, which might be a better compromise.
It would certainly need some prototyping.
Apple gets 1 year of battery life from 225mah. So, it seems reasonable to get a month from 30mah. Not great, but hey, we're just entertaining the packaging requirement.