Apple Watch Series 3 Cellular / Purchased 11/02/2017
OK...
This is the first time I ever checked battery health on my watch.
Settings > Battery > Battery Health
MAXIMUM CAPACITY: 100%
I wear it everyday, charge it every night.
Seems a little suspect to me... 🤷♂️
Yeah, this is true for my daughters 4 year old Series 3 too.
I don’t think the battery health is calibrated properly to measure the Series 3 and older. This feature was introduced with the Series 5 and makes certain assumptions about the battery and drain rate. The Series 3 battery is almost 20% larger than the Series 4 and there is no always-on display.
My theory is that this feature is most accurate with Series 5 & 6.
Series 4 has wonky readings due to no AOD but the battery size is closer to Series 5 so it’s not as far off as the Series 3.