Best Backup Power for a CPAP Machine in 2026
The EcoFlow River 2 is our top pick on published specs. Four CPAP backup options compared, with the makers' own statements on medical use.
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EcoFlow River 2
On published specifications the EcoFlow River 2 ranks first of the four compared here: EcoFlow lists 243Wh (Amazon lists 256Wh), 300W output and a full wall recharge in about an hour, for $209. The Jackery Explorer 240 v2 lists 256Wh and 300W and is the lower-priced alternative, though Jackery's own site currently lists only a refurbished unit. The Medistrom Pilot-24 Lite is a dedicated CPAP battery that retailers list at 95Wh with a DC output, for specific ResMed models. The makers' own statements: EcoFlow says its power stations are not intended to power life-sustaining medical equipment, including hospital-grade CPAP devices, and advises confirming compatibility with the device maker or your healthcare provider. Jackery says its power stations are not recommended for use with medical devices.
Check Price on AmazonAt a Glance
| Feature | EcoFlow River 2 | Jackery Explorer 240 v2 | Medistrom Pilot-24 Lite | Anker 521 PowerHouse |
|---|---|---|---|---|
| Price | $209 list | $199 | $339 (retailer listings) | $229.99 |
| Capacity | 243Wh per EcoFlow (256Wh on Amazon) | 256Wh per Jackery | 95Wh per retailer listings | 256Wh (LiFePO4) per Amazon listing |
| Output | 300W (600W X-Boost) | 300W | 24V DC to the machine | 300W (600W peak) |
| Output Waveform | Not stated on EcoFlow's US spec sheet | Not stated on Jackery's product page | DC output (no AC inverter) | Not confirmed on a current Anker product page |
| Recharge | ~60 minutes to full from the wall | Not compared | 2-3 hours per retailer listings | Not compared |
| Weight | 3.5kg | Not compared | 560g per retailer listings | Not compared |
Quick Comparison
Our Top Picks
EcoFlow River 2
Lists 243Wh (Amazon lists 256Wh) and 300W output, with a full wall recharge in about an hour per EcoFlow, for $209.
- 300W output with a 600W X-Boost mode, per EcoFlow
- Full recharge from the wall in about 60 minutes, per EcoFlow
- Under 30 ms EPS auto-switch for essential devices, per EcoFlow
- 3000 cycles to 80% capacity, per EcoFlow
- 7.7 lb (3.5 kg)
- Wi-Fi and Bluetooth app control, per EcoFlow
- EcoFlow's US spec sheet does not state the output waveform
- EcoFlow says its power stations are not intended to power life-sustaining medical equipment, including hospital-grade CPAP devices
- Capacity is 243Wh on EcoFlow's page and 256Wh on Amazon, so check the listing you buy
- EcoFlow lists no extra battery for it
Jackery Explorer 240 v2
Lists 256Wh and 300W with a 100W USB-C port. Jackery's own site currently lists only a refurbished unit ($249, 6-month warranty).
- 256Wh and 300W output, per Jackery
- One 100W USB-C port and one 15W USB-C port, per Jackery
- As of 2026-10-02 Jackery's own site lists only a refurbished unit ($249, 6-month warranty), so check where you can buy it new
- Jackery says its power stations are not recommended for use with medical devices
- Jackery's product page does not state the output waveform
Medistrom Pilot-24 Lite
A dedicated CPAP battery. Retailer listings give 95Wh, a 24V DC output and 560 g, for specific ResMed models.
- Retailer listings give 560 g (1.3 lb), the lightest of the four
- DC output (24V) straight to the machine, so no AC inverter
- Retailer listings give a 2-3 hour recharge
- 95Wh per retailer listings, the smallest capacity of the four
- Retailer listings say it is made for specific ResMed models (AirSense 10, AirMini and AirCurve), so it only suits those
- About $339 on retailer listings, the highest price of the four
Anker 521 PowerHouse
The Amazon listing gives 256Wh, 300W (600W peak), a LiFePO4 battery, 6 ports and a 60W USB-C output, at $229.99.
- 256Wh LiFePO4 battery, per the Amazon listing
- 300W output (600W peak) with two AC outlets, per the Amazon listing
- 60W USB-C output and 6 ports in total, per the Amazon listing
- Anker's own product pages did not load when we checked, so we could not confirm specs with the maker
- The waveform is not stated in the Amazon listing text we read
- Higher list price than the Jackery and the EcoFlow
How This Was Researched
We compare specifications published by the makers or listed by retailers: watt-hours, output, recharge time, weight, and the output waveform where it is stated. We have not tested these products with any CPAP machine and make no claim that they are suitable for one. Prices were read at the time of writing. Statements attributed to a maker are the maker's own.
Frequently Asked Questions
EcoFlow says its power stations are not intended to power life-sustaining medical equipment, including hospital-grade CPAP devices, and advises confirming compatibility with the device maker or your healthcare provider. Jackery says on its product page that its power stations are not recommended for use with medical devices or life-support equipment. We did not find a statement on medical use on the Amazon listing for the Anker 521 or in retailer listings for the Medistrom. These are the makers' statements, not ours.
Compare the watt-hours and output the maker lists with the rated draw in your own device's manual. Runtime is roughly watt-hours divided by the load in watts, before conversion losses. Also check whether the maker states the output waveform, whether the output is AC or DC, any compatibility list, and any position the maker takes on medical use.
A dedicated battery such as the Medistrom Pilot-24 Lite has a DC output for specific machines, a small capacity (95Wh per retailer listings) and a low weight. A general power station such as the EcoFlow River 2, Jackery Explorer 240 v2 or Anker 521 has AC outlets and USB ports, a larger capacity (243-256Wh) and more weight, and can power other devices.
EcoFlow's US River 2 page and Jackery's product page do not state it. The Anker 521 is not confirmed on a current Anker page. The Medistrom has a DC output, so it has no AC waveform.
EcoFlow River 2
Lists 243Wh (Amazon lists 256Wh) and 300W output, with a full wall recharge in about an hour per EcoFlow, for $209.
Check Price on Amazon