Nominal Voltage
Definition
Representative voltage of a battery cell or pack, typically near mid-point of discharge. For lithium-ion cells, typically 3.6V or 3.7V depending on chemistry.
Why It Matters
- Used for system voltage specification and design
- Actual voltage varies from max (4.2V) to min (2.5-3.0V) during discharge
- Pack nominal voltage = cell nominal voltage × series count
- Does not directly indicate state-of-charge
Common Pitfalls
- Confusing nominal voltage with actual operating voltage
- Not considering voltage sag under load
- Designing systems that only work at nominal voltage
- Not accounting for voltage window across temperature range