Convert Electronvolts to Watt-Hours
Convert Electronvolts (eV) to Watt-Hours (Wh) instantly and accurately.
Conversion Formula
Wh = eV × 4.450490650e-23
About Electronvolts
An electronvolt (eV) is the kinetic energy gained by one electron accelerated through 1 volt - exactly 1.602176634 × 10⁻¹⁹ J (fixed by the 2019 SI revision). It is the natural energy unit of atomic and particle physics: visible light photons carry 1.7-3.1 eV; hydrogen ionisation requires 13.6 eV; X-ray photons span 100 eV-100 keV; protons at the LHC reach 6.5 TeV. Rest masses use eV/c²: electron 0.511 MeV, proton 938.3 MeV, Higgs boson 125 GeV. Nuclear binding energy peaks at ~8 MeV/nucleon for iron-56. 1 eV = 1.602176634 × 10⁻¹⁹ J.
About Watt-Hours
A watt-hour (Wh) is the energy delivered by 1 watt for one hour - exactly 3,600 J. It is the practical unit for small-scale electrical energy: a 10,000 mAh 5 V power bank stores 50 Wh; a laptop battery holds 50-90 Wh; a smartphone battery holds 10-15 Wh; an AA alkaline cell stores ~3 Wh. LED lamps labelled 9 W save 51 Wh/h over a 60 W incandescent. IATA dangerous-goods rules use Wh as the threshold for lithium batteries in aircraft: cells >20 Wh and batteries >100 Wh need special approval. 1 Wh = 3,600 J = 3.412 BTU.
Quick Reference Table
| Electronvolts (eV) | Watt-Hours (Wh) |
|---|---|
| 1 eV | 4.45 × 10-23 Wh |
| 2 eV | 8.901 × 10-23 Wh |
| 5 eV | 2.225 × 10-22 Wh |
| 10 eV | 4.45 × 10-22 Wh |
| 25 eV | 1.113 × 10-21 Wh |
| 50 eV | 2.225 × 10-21 Wh |
| 100 eV | 4.45 × 10-21 Wh |