iPhone XS L-shaped battery revealed after teardown
The first batch of iPhone XS and XS Max have now been released to the wild now. And as usual, lots of teardown videos started popping up. One of the most famous teardown master, iFixIt, is quick to the action and got the XS stripped day one, revealing an interesting layout in the premium smartphone.
As it turns out, Apple has equipped iPhone XS with an L-shaped battery. This approach is far different from the dual battery implementation on last year’s iPhone X which is something that the company has carried forward to iPhone XS Max.
At the same time, iFixit’s teardown also confirmed the previous report that the battery capacity of the iPhone XS is smaller than iPhone X. Specifically, iPhone XS’ battery is rated at 10.13 Wh/2659 mAh as opposed to iPhone X’s 10.35 Wh/2716 mAh which is not exactly that far off from each other.
The new design approach for non-rectangular batteries removes material from one or more of the layers before they can be stacked. Apple has been filing patents in this direction since 2011. The challenge with any lithium-polymer battery cell is that each corner needs to be sealed to prevent undue stress from thermal expansion—and since the battery of the XS has 6 sides vs. the traditional 4, those extra corners can be tricky. To reduce the stress on the corners, Apple notched the internal corner of the battery (as described in this 2016 patent). This dramatic shift opens up a lot of design possibilities, but the large notch is responsible for the decrease in capacity relative to the X. Only time will tell how this new cell performs with age—both of these batteries are still limited to 500 charge cycles.
If you are interested in taking a deeper look at the internals of iPhone XS and iPhone XS Max, check out the excellent teardown by iFixit team here.