How to size a CPAP backup battery

Last updated: September 25, 2026. Not a lab test. Hours below are arithmetic: published watt-hours ÷ a cited device watt figure. We did not run a CPAP overnight. This is not medical advice.

Size the battery from two numbers: the machine’s watts, and the battery’s watt-hours.

ResMed’s AirSense 11 user guide lists a 65 W power supply, typical consumption 56.1 W, and peak 73.2 W. Use your own machine’s manual if you do not have an AirSense 11.

Hours ≈ battery Wh ÷ device watts.

An 8-hour night at ResMed’s typical 56.1 W needs 449 Wh of usable energy before inverter losses. Humidifier and heated hose sit inside that typical/peak range. They are not extra mystery watts. A DC 24 V PAP battery skips the inverter. An AC power station does not, so real AC hours will be shorter than the raw divide.

Current shortlist (makers’ Wh only)

Expectation vs reality: CPAP battery claims

Expectation: the watt-hour sticker equals a full humidifier night. Reality: you still have to divide — and settings matter.

• Wh ÷ W is the claim check. Hours ≈ published battery Wh ÷ a cited device watt figure (here, ResMed AirSense 11 typical 56.1 W from the user guide, unless your manual differs). That is arithmetic, not an overnight lab run on this site.
• Pressure, heat, and hose. Humidifier and heated hose sit inside the maker’s typical / peak range on the AirSense 11 guide. They are not “mystery extras,” but higher settings push you toward the peak side of that band — still use your own manual.
• DC vs AC path. A dedicated 24 V PAP battery skips the inverter. An AC power station does not, so real AC hours land shorter than the raw divide even when Wh looks large on paper.

Shortlist hours on this page are labeled arithmetic from maker Wh and the cited watt figure. Medistrom’s “1–2 nights” line is their claim with humidifier/heated tubing disabled — not a test we ran. This is not medical advice.

Medistrom Pilot-24 Lite — 95 Wh, DC 24 V

Medistrom’s product page lists 95 Wh, DC 24 V at 3.75 A. It is a dedicated 24 V PAP battery, not a wall-outlet station. Medistrom says 1–2 nights with humidifier and heated tubing disabled. That is their claim, not a test we ran. At ResMed’s typical 56.1 W the raw divide is 1.7 hours.

Jackery Explorer 300 Plus — 288 Wh

Amazon listing for this Jackery ASIN has been soft-unavailable in recent checks — prefer Jackery US below.

Jackery’s US page lists 288 Wh and 300 W AC (model JE-300B). At 56.1 W the raw divide is 5.1 hours. That is short of an 8-hour humidifier night on the AC path.

Check Jackery Explorer 1000 v2 (Jackery US)

Jackery Explorer 1000 v2 — 1070 Wh

Jackery US publishes 1070 Wh, 1500 W rated AC (3000 W surge), two USB-C ports rated 100 W Max and 30 W Max, an 18 W Max USB-A port, and a 12 V⎓10 A car port. It uses LiFePO₄ chemistry and is rated for 4000 cycles to 70%+ capacity. At ResMed’s typical 56.1 W, the arithmetic is 1070 ÷ 56.1 ≈ 19.1 hours. That clears 449 Wh on paper on the AC path; real AC hours will be shorter than the raw divide. The official Jackery store showed the basic 1000 v2 kit Sold Out when checked September 14, 2026. Jackery’s FAQ says its portable power stations are not recommended for medical or life-support devices, so confirm suitability with your equipment maker.

BLUETTI AC70 — 768 Wh

Amazon listing for this BLUETTI kit ASIN has been soft-unavailable in recent checks — prefer BLUETTI US below.

BLUETTI’s US page lists 768 Wh and 1,000 W AC. At 56.1 W the raw divide is 13.7 hours. That clears 449 Wh on paper. The official store showed the unit out of stock when we checked September 16, 2026.

Check price at BLUETTI

Confirm cable kits and machine voltage with the battery maker before you buy. See also our guides hub and portable power stations.

If you were chasing a river turbine for trip charging instead of a CPAP-sized station, start with our WaterLily turbine alternative (what is left after Seaformatics stopped selling) — that product is no longer sold.