iPhone SE restarted yesterday in the cold (10% battery remaining)

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I went outside with my Son to take some pictures of a fallen tree and a video of another tree that was about to fall due to strong winds. He has a homework assignment to write about a real event, and he wanted to write about the storm w had yesterday.

As I was shooting the video, the iPhone shut down restarted by itself but it seemed to take longer than usual. we went back inside, iPhone already restarted by itself, 10% battery remaining. Looking at the log, it appears the battery level was ~35% and then went down quite fast as I was shooting the video (and yes, it was cold outside, around 36F with strong winds)

iOS says I have 89% of the original capacity and battery is operating at peak performance.

I will probably wait another few months and get a new battery ($49). The iPhone is almost 3 year old.