The Term gigafactory is doing the heavy lifting in this sentence.
There are a lot of smaller scale operations that do design, development and assembly in Europe like Varta Microbattery[1]. They provide a lot of the batteries used in the modern wireless earbuds like the airpods pro[2] and also some of the Samsung galaxy buds[3].
[1]https://en.wikipedia.org/wiki/VARTA
[2]https://www.ifixit.com/Teardown/AirPods+Pro+Teardown/127551 look at step 8
[3]mentioned in the same article and step as the Airpods above