Shimano Steps Ride + E6000 Séries Mode D'emploi page 24

Battery level indicator
You can check the battery level on the cycle computer while riding.
<SC-E6000>
Display Battery level
81 - 100%
61 - 80%
41 - 60%
21 - 40%
1 - 20%
0%
19
<SC-E6010>
Display Battery level
100%
0%