I’ll just say this is “AWESOME” I’ve been taught all code is garbage! LOL My code that is 
This is some of the best code I’ve seen on this Forum. Clean and well documented. Seeed Should hire you to re-write their examples. Thank you very, very much for sharing. So many of us just need that little push in the right direction and to learn a little style and good technique. I have struggled with the battery voltage methods and all of my outcomes have been unreliable. I also need to get the IMU data on my BLE app, but only to detect or sense motion or if the item has been moved, picked up, or dropped. I love the journey but my eyes are tired and red. LOL 
Thanks again and please continue to share this very interesting project and Your approach to solving the challenges that it and Seeed Studio present … 
GL :-p