Hi there,
That doesn’t seem quite right. Given the battery life calculator on Digikey and others, for a single-cell LiPo battery, the “3.85V” rating is typically the nominal voltage. In practice, a LiPo battery usually measures around:
- Fully charged: about 4.2V
- Nominal voltage: roughly 3.7V to 3.85V
- Discharged (cutoff): around 3.0V
So, during normal operation, you might see a voltage range from about 4.2V down to around 3.0V many nRF52840-based boards include a voltage regulator that can take the full battery range (4.2V to ~3.0V) and provide a steady operating voltage for the chip.
this just adds to the miss of the Mark iIMO…
HTH
GL 
PJ 