> "... 100 microwatts, a voltage of 3V, and a volume of 15 X 15 X 5 cubic millimeters ..."
> 3-4 orders below the power requirements for a phone. An AirTag-type intermittent device, though...
If my maths is right (and it's past midnight, and I'm not entirely sober, so might not be) and my search results are too, 15 x 15 x 5 cubic millimeters is approximately 9.68 times smaller than an iPhone battery (95 mm x 37.6 mm x 3.05 mm, ish), but if energy capacity scales linearly to volume then its ~12,500 times lower capacity per volume than an iPhone battery.
That’s 100 microwatts x100 years, so about 876 wh, or 292 amp hrs (292,000 mah)
But, still, only 80mah a day . So 750mah scaled up to iPhone battery size. So abut 1/5 of the average daily power requirement for an iPhone. Even at that rate you’d need to use a supecapacitor to even out the load profile.
OTOH, in terms overall energy, it would be about the same as about a 50 litre lithium ion so it is rediculously dense, just low output
1/5 the daily power requirement is surprisingly decent. Swapping out the screen for an eink display or ultra low power LCD like those from PixelQi and downclocking the SoC might be enough to make up that gap.
FYI, your comment made me look up PixelQi and Wikipedia says that conpany died almost a decade ago (although 2015 feels to me like much, much less than a decade ago):
> "By 2015, PixelQi's team and offices were unreachable, and the company is presumed defunct.[3] The intellectual property is now owned by the original investor of Pixel Qi, while the right to manufacture Pixel Qi technology contractually rests with Tripuso Display Solutions.[4][5]"
> 3-4 orders below the power requirements for a phone. An AirTag-type intermittent device, though...
If my maths is right (and it's past midnight, and I'm not entirely sober, so might not be) and my search results are too, 15 x 15 x 5 cubic millimeters is approximately 9.68 times smaller than an iPhone battery (95 mm x 37.6 mm x 3.05 mm, ish), but if energy capacity scales linearly to volume then its ~12,500 times lower capacity per volume than an iPhone battery.