Apple Watch Series 3 Teardown Reveals Larger Battery and Air Vent Moved Next to Diagnostic Port

iFixit has completed a teardown of the Apple Watch Series 3, which has a virtually identical form factor as previous models.

apple watch series 3 teardown ifixit
The display is unchanged from the Series 2, with one key difference being that it now functions as a multifrequency antenna for cellular. Series 3 models support LTE and UMTS, according to Apple's tech specs.

series 3 display
The battery in the 38mm model with GPS + Cellular has a capacity of 279 mAh at 3.82V, or 1.07 watt hours, which is only a slight increase of about 3.8 percent over the 38mm Series 2 model without cellular.

Apple said Series 3 models with cellular get up to 18 hours of battery life, including four hours of LTE and 14 hours of connection to an iPhone via Bluetooth. Series 2 models are also rated to last 18 hours with mixed usage.

apple watch series 3 battery
iFixit was surprised that Apple managed to increase the battery size while still leaving room for the added functionality of cellular antennas, radios, power amplifiers, the embedded SIM card, and so on in the same form factor.

The embedded SIM, outlined in red, appears to be sourced from ST Microelectronics, and it is positioned next to a Wi-Fi module from Broadcom and other RF chips that enable cellular capabilities in the watch.

series 3 rf chips
Last, we finally know what the tiny meshed hole is next to the diagnostic port: it's an air vent, since the Apple Watch Series 3's new barometric altimeter took over the vent's previous location next to the microphone.

apple watch series 3 air vent

Apple Watch Series 3's relocated air vent outlined in yellow

iFixit gave the Apple Watch Series 3 a repairability score of 6 out of a possible 10 points. Display repairs and battery replacements are both possible, albeit tricky, but replacing any of the component cables requires micro-soldering.

Related Roundup: Apple Watch Series 7
Buyer's Guide: Apple Watch (Neutral)
Related Forum: Apple Watch

Top Rated Comments

TheBing1980 Avatar
61 months ago
I hope we see some real world battery life for the same watch when NOT on LTE. I want to get the GPS version. Since Apple tends to underestimate I'm hoping we get 24-26 hours of uses when not using LTE.
I just upgraded from a Series 0 to the LTE Series 3.

So far I am very impressed with the improved battery life.

Yesterday I was up at 7am and used the watch all day. (included a 45 min working with the heart rate monitor on) At 11pm I still had 70% battery remaining.

I had my phone with me, so I doubt I used any cellular data that day.
So my guess is that you may be able to get 24 hours with the GPS version.
Score: 3 Votes (Like | Disagree)
lincolntran Avatar
61 months ago
What kind of air flow could they possibly get through that vent when it is almost constantly occluded by a watch band?
I don’t think that’s its purpose. There’s no fan so there really isn’t any airflow at all. I’m not an electrical engineer but my guess that I think the main purpose of to just have an outlet to let the hot air out when there’re build up of pressure inside the watch housing as it’s not good to have a totally closed enclosure for any electronic device.
Score: 3 Votes (Like | Disagree)
porkrind Avatar
61 months ago
What kind of air flow could they possibly get through that vent when it is almost constantly occluded by a watch band?
They need almost zero flow. It just needs to move enough air to equalize the pressure inside and outside the watch. It's a minuscule requirement.
Score: 2 Votes (Like | Disagree)
MrXiro Avatar
61 months ago
I hope we see some real world battery life for the same watch when NOT on LTE. I want to get the GPS version. Since Apple tends to underestimate I'm hoping we get 24-26 hours of uses when not using LTE.
Score: 1 Votes (Like | Disagree)
iPhysicist Avatar
61 months ago
They need almost zero flow. It just needs to move enough air to equalize the pressure inside and outside the watch. It's a minuscule requirement.
This. Atmospheric pressure equalization.
Score: 1 Votes (Like | Disagree)
Relentless Power Avatar
61 months ago
It's pretty unbelievable the amount of technology that can incorporated into such a small casing that can fit in the palm your hand. And yet it's features and capabilities have something for everybody to convenience us in fitness and communication.
Score: 1 Votes (Like | Disagree)

Popular Stories

RIP iPod Feature

RIP iPod: A Look Back at Apple's Iconic Music Player Over the Years

Friday May 13, 2022 2:25 pm PDT by
Apple earlier this week announced the discontinuation of the iPod touch, and because it was the last iPod still available for purchase, its sunsetting effectively marks the end of the entire iPod lineup. To send the iPod on its way, we thought it would be fun to take a look back at some of the most notable iPod releases over the last 21 years. Original iPod (2001) Introduced in October...
iOS 16 mock for article

Gurman: iOS 16 to Include New Ways of System Interaction and 'Fresh Apple Apps'

Sunday May 15, 2022 6:14 am PDT by
iOS 16 will include new ways of interacting with the system and some "fresh Apple apps," Bloomberg's Mark Gurman has said, offering some more detail on what Apple has in store for the upcoming release of iOS and iPadOS set to be announced in a few weeks at WWDC. In the latest edition of his Power On newsletter, Gurman wrote that while iOS 16 is not likely to introduce a major face-lift to...
14 16 inch 2021 mbps back to back feature orange

Five Things You Still Can't Do With a MacBook Pro

Wednesday May 11, 2022 11:16 am PDT by
It's been over 200 days since Apple debuted its redesigned MacBook Pro lineup. Offered in 14-inch and 16-inch display sizes, the new-look MacBooks wowed Apple fans and creative pros alike with their powerful custom Apple silicon, mini-LED screen, and multiple connectivity options. But there are still some things you can't do with a MacBook Pro. Here are five features some Mac users are still...
iOS 16 mock for article

Which Devices Will iOS 16 and iPadOS 16 Support?

Thursday May 12, 2022 7:29 am PDT by
While there are as yet no concrete rumors related to which devices iOS 16 and iPadOS 16 will support, the discontinuation of the iPod touch earlier this week may be an indication that as many as nine devices could be about to lose support for Apple's upcoming operating systems. iOS and iPadOS 13, 14, and 15 support all of the same devices, with the iPhone 6S and iPhone 6S Plus,...
apple mac ipad watch trade in

Apple Launches Limited-Time Bonus Trade-In Credit for iPhone, iPad, Mac, and Apple Watch in Many Countries

Wednesday May 11, 2022 5:14 am PDT by
Apple has launched a special limited-time offer for iPhone, Apple Watch, Mac, and iPad trade-in that offers customers additional credit when trading in their only device for a new one. The offer is being run in several countries including the US, UK, Germany, Spain, Italy, South Korea, Japan, Taiwan, China, India, and France. In the UK, Apple is offering up to £50 of extra trade-in credit...
sony

Sony Unveils Redesigned WH-1000XM5 Headphones With Improved Noise Cancelation

Thursday May 12, 2022 9:26 am PDT by
Sony's flagship WH-1000XM4 noise-canceling headphones have been among the best on the market for some time, and today Sony announced its fifth-generation WH-1000XM5 headphones, boasting a new design and several improvements over the previous model. The redesigned headphones replace the shrouded arms that swivel on the XM4's with an exposed arm that has a single contact point at the earcups,...
apple tv 4k design clue

Kuo: New Apple TV to Launch in Second Half of 2022, Lower Price Possible

Friday May 13, 2022 7:58 am PDT by
Apple plans to launch a new version of the Apple TV in the second half of 2022, according to well-known analyst Ming-Chi Kuo. In a tweet today, Kuo said the new Apple TV will have an improved cost structure, suggesting that the device could have a lower price that is more competitive with other streaming media players like Google's Chromecast line, Amazon's Fire TV line, and the Roku line. ...
iPhone 14 Purple Feature

Full Range of iPhone 14 Color Options Revealed by Purported Leak From China

Wednesday May 11, 2022 2:20 am PDT by
The iPhone 14 and iPhone 14 Pro models will be available in a refreshed range of color options, including an all-new purple color, according to a recent rumor. The claim comes from a post on Chinese social media site Weibo by an unverified source and purports to reveal the full range of color options for Apple's upcoming iPhone 14 and iPhone 14 Pro models. Compared to the selection of color...