This is for someone who wants to charge an OutIn machine on a trip, from a power bank or a vehicle. We read OutIn's public product pages, FAQ answers and policies on 2026-10-20 (outin.com). We have not tested any OutIn product. We have not tested charging. The page does not recommend any power bank brand.
What OutIn states, and the blanks
| Battery | Wh stated? | Charging input stated | Time to charge | Brews, room-temp water | |
|---|---|---|---|---|---|
| Nano 1 | 2,500 mAh 3S | blank | USB charger over 10W, or 12V/24V car charger | 180 min (from the Nano 2 page) | up to 5 |
| Nano 2 | 5,000 mAh 3S | 54 Wh | 45W USB-C PD. Car charging: blank | about 100 min | up to 9 |
| Mino | 3,000 mAh 3S | blank | 20V 1.5A, 30W. Car charging: blank | 20% to 80% in 45 min, full in about 90 min | up to 6 |
| Fino grinder | 2 x 1,000 mAh | 7.4 Wh (gift set page) | blank | 1 hour | grinds over 324 g of beans per charge |
All brew counts are OutIn Lab figures for 50 ml heated from 25°C. Charging losses, the effect of cold weather on a full charge, and how Mino behaves on a lower-power port are not stated on the pages we read. Ask OutIn before you rely on any of them.
The arithmetic, and which parts are ours
Watt-hours = amp-hours × volts. OutIn gives Nano 2 as 5,000 mAh and 54 Wh, which implies 10.8 V (54 ÷ 5). If OutIn's other "3S" packs use the same 10.8 V, which OutIn does not say, then Nano 1 is about 27 Wh and Mino about 32 Wh. Dividing by OutIn's brew counts gives roughly 5.4 to 6 Wh per room-temperature brew for all three. That is our division of OutIn's own numbers, not an OutIn figure.
A sanity check on those numbers: heating 50 g of water by 68°C takes about 14 kJ, or 4 Wh, using the standard 4.18 J per gram per degree for water. So the lab brew counts are the right size. This is our arithmetic and not a measurement of any machine.
Sizing a power bank
- Read the machine's input: 45W for Nano 2, 20V 1.5A for Mino.
- Read the power bank's label for its capacity in Wh, and its highest output in watts. If it lists only mAh, check which voltage that mAh is quoted at.
- If the bank's output is below the machine's input, charging may be slower than OutIn's stated time. OutIn does not say what happens.
- Divide the bank's Wh by the machine battery's Wh for full recharges, before any losses.
Example with made-up numbers: a bank labeled 60 Wh holds enough for about one full Nano 2 recharge (60 ÷ 54), and in theory about ten room-temperature brews (60 ÷ 6), before losses. Real figures will be lower. For car power, OutIn states 12V/24V charging for the Nano 1 only.
The way around the problem
Heating the water is what drains the battery. OutIn says Nano 2 can do "over 600 extractions" with preheated water, and says Nano 1 does "over 200 brews using hot water on a single charge". Those are its lab figures. If you carry a flask or a stove, pour in hot water and the power question mostly goes away. For a whole camp's worth of power, see our portable power stations guide.
What the sources do not say
- Wh for Nano 1 and Mino, charging efficiency, cold-weather performance and battery lifespan.
- Car charging for Nano 2 and Mino, and what charging gear comes in the box.
- Any tested power bank. We recommend none.