What are these white vertical lines on Battery Graph when charging?

[gerrya]

These 2 screenshots are from 2 different phones when charging? Both have 2 breaks(Vertical lines)?
Thanks,

 

[Mooncatt]

Is it possible the phone rebooted during those times? I know if it's powered off, some apps leave a blank spot in their graph.

 

[gerrya]

Could be, just weird that it happened on 2 different phones