You're not imagining it: The original Pixel Watch is indeed taking longer to charge after this change
Google increased the quoted charging speeds for the first-generation Pixel Watch in a past firmware update. This means that it now takes longer to charge the watch than it did when it was first released.
As reported by 9to5Google, the company quietly updated the support page for the device to reflect the new charging times. Additionally, the company confirmed the change directly to the publication by stating "a firmware update for Google Pixel Watches required us to review the charging times, the new times are what the average user will experience," with no further explanation.
Basically, if you own the original Pixel Watch, you may have noticed that it now takes at least 15 minutes longer to charge than it did before. Charging times have increased from 30 minutes to 45 minutes to go from 0% to 50%, 55 minutes to 75 minutes to go from 0% to 80%, and 80 minutes to 110 minutes to go from 0% to 100%. It is important to note that these are just estimated charging times, dependent on a number of factors, such as the ambient temperature and the condition of the battery.
Since Google has not explained why the charging times have been increased, we can only speculate that this re-assessment came about due to the release of the Pixel Watch 2. The new watch sports a newer processor and a slightly larger battery, as well as a new magnetic charging puck that uses a pin mechanism instead of just relying on magnets. Google claims that the Pixel Watch 2 lasts longer between charges and it's possible the company arrived at this conclusion while testing this claim.
The Pixel Watch 2 and its new charging puck. Image credit - PhoneArena
Another possibility is that thermal concerns after a full charging session may be to blame. As a Pixel Watch owner I do find that it can get pretty warm while charging, to the extent that I usually opt to wait about a minute or two to wear it after removing it from the charger. Similar reports from users, plus complaints of the glue that holds the backplate coming undone, may have prompted Google to make changes to the firmware which brought about this change.
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