Smartphone charging: how much battery you need
Smartphone charging draws about 15 W (10–25 W range), runs 100% of the time and uses 30 Wh per day. Start-up surge: 15 W.
A full charge is ~15–20 Wh; a 1 kWh station charges a phone 40+ times.
Battery needed
| Hours | Wh | Battery (Wh) | Inverter (W) |
|---|---|---|---|
| For 8 hours | 10 | 16 | 17 / 15 |
| For 24 hours | 30 | 46 | 17 / 15 |
| For 72 hours | 90 | 137 | 17 / 15 |
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Stations that fit (24 h)
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FAQ
How many watts does a Smartphone charging use?
Typically 15 W while running, with a range of 10–25 W depending on model and age. Start-up surge can reach 15 W.
How long will a 1000 Wh power station run a Smartphone charging?
About 44 hours on the clock, allowing for the 100% duty cycle, inverter losses and a 20% reserve.
What size power station do I need for a Smartphone charging overnight (8 h)?
About 16 Wh of battery and an inverter rated at least 17 W continuous with 15 W surge.
Can I run a Smartphone charging on solar during an outage?
You need roughly 20 W of panels in winter to replace a day's use (30 Wh), charging through a station with a big enough MPPT input.
Other appliances
1 Approximate values: estimated from motor or heater power and typical figures published online, not from a manufacturer chart. Check your appliance label.
Inverter efficiency 88%, usable depth of discharge 90%, reserve 20%. Full method: How we calculate. source