To start, both the 40mm and 44mm models of the latest Apple Watch see an increase in battery capacity compared to the Series 5 models. That being said, the increase in size is minimal, with the differences being 8.5% and 3.5% for the 40mm and 44mm models, respectively. The tiny increase may explain why both models still have the 18-hour battery life as the previous series.
The Apple Watch Series 6 also sees the absence of the Force Touch gasket, which means no pressure sensitive touch sensors. On one hand, that’s the loss of a feature that’s unique among commercial smartwatches. On the other, iFixit says the lack of such a fragile component makes them easier to repair. One component of the Apple Watch Series 6 that iFixit did not take apart from the rest of the device. And it’s the blood oxygen sensor. This is simply because it’s fused to tightly together that attempting to take it apart will just break it. Ultimately, the 6th generation Apple Watch gets a repairability score of 6/10. (Source: iFixit)