CPAP Battery Calculator
How many nights will your battery last? Select your machine and battery to get an instant estimate with FAA travel status.
Runtime estimates are based on manufacturer-published specs where available and are approximate. Actual runtime varies with pressure, altitude, temperature, leak rate, and battery age.
Product specifications, pricing, and availability may change without notice. Always verify current specs and compatibility with the manufacturer or retailer before purchasing. CPAP Clarity is not affiliated with any battery or CPAP manufacturer.
Humidifier Setting
Power draw: 9W
10.6h
Total Runtime
1.4
Nights (7.5h sleep)
Yes
Fly With It?
FAA Carry-On Approved
Under 100Wh. No airline approval needed.
How We Calculated This
Shop Medistrom Pilot-24 Liteon Amazon →
$300 to $350 (pricing as of April 2026)
All Batteries with ResMed AirSense 11 (no humidifier)
| Battery | Runtime | Nights | Weight | FAA | Price |
|---|---|---|---|---|---|
| Medistrom Pilot-24 Lite | 10.6h | 1.4 | 1.3 lbs | Yes | $300 to $350 |
| EXP96 Pro | 34.1h | 4.5 | 6.5 lbs | No | $250 to $300 |
| ResMed Power Station II | 10.8h | 1.4 | 2.04 lbs | Yes | $200 to $250 |
| Jackery Explorer 240(AC) | 22.7h | 3 | 8.6 lbs | No | $200 to $250 |
| Jackery Explorer 300(AC) | 27.7h | 3.7 | 7.1 lbs | No | $250 to $300 |
| Goal Zero Yeti 200X(AC) | 17.7h | 2.4 | 5 lbs | No | $250 to $300 |
| Bluetti EB3A(AC) | 25.3h | 3.4 | 10 lbs | No | $200 to $250 |
The Humidifier Is the Variable
Modern CPAP blower motors draw just 9W without a humidifier. Turn on the heated humidifier and that jumps to 25W. Add a heated tube and you are looking at 50W. For travel, turning the humidifier off is the single biggest way to extend battery life. If you need moisture, consider a passive HumidX insert (AirMini) or an inline moisture exchanger that requires no power.
Related Resources
CPAP Travel Battery Guide: DC vs AC, FAA Rules, and What to Buy →
Everything you need to know about powering your CPAP away from home.
Best Travel CPAP Machines in 2026 →
Compare the AirMini, Transcend Micro, Z2 Auto, and more by size, weight, and battery life.
Analyze Your CPAP Data →
Import your SD card for detailed therapy analysis. See how your AHI, leak, and pressure look night by night.
Runtime estimates are approximate and may not reflect your actual experience. Always carry your AC adapter as a backup when traveling with battery power.
Understanding CPAP Battery Power
Why Battery Runtime Varies So Much
If you have ever searched for CPAP battery runtime estimates, you have seen wildly different numbers. One review says a battery lasts 3 nights. Another says it barely makes it through one. Both can be correct because the variable that matters most is not the battery or the machine. It is the humidifier.
A modern CPAP motor draws remarkably little power on its own. The ResMed AirSense 11 draws about 9 watts in typical use without the humidifier (per the ResMed battery guide). That includes the blower, display, and WiFi. Turn on the heated humidifier and the draw jumps to 25 watts. Add the heated tube and it climbs to 50 watts. A battery that lasts 10 hours dry will last under 2 hours with the heated tube running.
DC-Direct vs AC-Inverter Batteries
CPAP-specific batteries like the Medistrom Pilot-24 Lite and EXP96 Pro connect directly to your CPAP machine's DC power input using a dedicated cable. This is called DC-direct connection. No energy is wasted in conversion, so you get the full rated capacity of the battery.
General-purpose portable power stations from Jackery, Bluetti, and Goal Zero use an AC inverter. They convert battery DC power to household AC (110V), then your CPAP's power adapter converts it back to DC. This double conversion wastes about 10 to 15 percent of the battery's capacity. A 240Wh Jackery delivers roughly 204Wh of usable power to your CPAP.
DC-direct batteries are smaller, lighter, and more efficient. AC-inverter batteries are larger but more versatile, since they can power any device with a standard plug. For air travel, DC-direct is almost always the better choice because the batteries are under 100Wh and FAA-approved.
FAA Lithium Battery Rules for Air Travel
The FAA regulates lithium batteries on commercial aircraft. The rules are straightforward:
- Under 100Wh: Carry-on approved. No airline approval needed. This covers most CPAP-specific batteries (Medistrom, EXP96 Pro, ResMed Power Station II).
- 100 to 160Wh: Carry-on allowed with airline approval. Contact your airline before travel. You may need to show the battery's Wh rating at the gate.
- Over 160Wh: Prohibited on all commercial flights. This includes most Jackery, Bluetti, and Goal Zero portable power stations.
CPAP machines themselves are always allowed on flights as medical devices. The TSA does not count a CPAP toward your carry-on limit. Bring your CPAP in a separate CPAP travel bag and inform the agent it is a medical device during screening.
Tips for Maximizing Battery Life
- Turn off the humidifier. This is the single biggest way to extend runtime, often by 5 to 10 times.
- Use a DC-direct battery. Avoid the 10 to 15 percent inverter loss.
- Lower your pressure if your provider approves. Higher pressure means more power draw.
- Reduce mask leak. High leak forces the motor to work harder, increasing power draw. Our leak fix guide covers practical solutions.
- Keep the battery warm. Lithium batteries lose capacity in cold weather. In freezing conditions, keep the battery insulated inside your tent or sleeping area.
- Charge fully before each trip. A partially charged battery is a partially useful battery.
Which Battery Should You Buy?
For air travel, a DC-direct battery under 100Wh is the clear choice. The Medistrom Pilot-24 Lite and EXP96 Pro are the two most popular options. Both are FAA-approved, weigh under 2 pounds, and provide 2 to 3 nights of runtime without a humidifier. If you use a ResMed AirMini, the ResMed Power Station II is purpose-built for that machine and stacks neatly underneath it.
For car camping, RV use, or extended off-grid trips where FAA rules do not apply, a larger portable power station makes sense. A 240 to 300Wh battery will run a CPAP without humidifier for 4 to 6 nights. Even with the humidifier on, you can get 1 to 2 nights from a single charge.
For a full comparison of travel CPAP options, see our guide to the best travel CPAP machines in 2026. And for a deeper look at choosing the right battery, read the CPAP travel battery guide.
Frequently Asked Questions
How long will a CPAP battery last?
A typical CPAP battery (90 to 100Wh) lasts 10 to 15 hours with the humidifier off at moderate pressure (10 to 12 cmH2O). That is 1 to 2 nights of sleep. With the humidifier on, runtime drops to 3 to 4 hours because heating water draws 15 to 40 additional watts. Heated tubes reduce runtime even further. The exact number depends on your machine, pressure setting, and battery capacity.
Can I bring a CPAP battery on an airplane?
Lithium batteries under 100 watt-hours (Wh) are allowed in carry-on luggage with no airline approval needed. Batteries between 100 and 160Wh require airline approval before boarding. Batteries over 160Wh are prohibited on commercial aircraft. Most CPAP-specific batteries (Medistrom Pilot-24 Lite, EXP96 Pro, ResMed Power Station II) are under 100Wh and FAA-approved. Larger portable power stations (Jackery, Bluetti, Goal Zero models over 160Wh) cannot fly.
What is the difference between DC-direct and AC-inverter batteries?
DC-direct batteries (like the Medistrom Pilot-24 Lite and EXP96 Pro) connect directly to your CPAP machine's DC power input. No energy is lost in conversion, so you get the full rated capacity. AC-inverter batteries (like Jackery and Bluetti portable power stations) convert battery DC to household AC, then your CPAP's power adapter converts it back to DC. This double conversion wastes roughly 10 to 15 percent of the battery's capacity. DC-direct batteries are smaller, lighter, and more efficient, but only work with specific CPAP models.
Should I turn off the humidifier when using battery power?
If maximizing runtime is the priority, yes. The humidifier is by far the biggest power draw on a CPAP machine. A ResMed AirSense 11 draws about 9 watts without the humidifier and 25 to 50 watts with it. Turning off the humidifier can roughly triple battery life. If you need moisture, consider a passive moisture exchanger like the ResMed HumidX (used with the AirMini) or an inline heat-moisture exchanger (HME) that requires no power.
Which CPAP machine is best for battery use?
Travel-specific machines draw the least power. The ResMed AirMini draws about 6 watts (per ResMed support documentation). Full-size machines like the AirSense 10 and 11 draw 7 to 9 watts without the humidifier, which is still very efficient. The biggest factor is not the machine but whether you use the humidifier. Any modern CPAP running dry will last multiple nights on a single battery charge.
How many watts does a CPAP machine use?
Modern CPAP machines use 6 to 11 watts without a humidifier, depending on the model and pressure setting. The ResMed AirMini draws about 6 watts (per ResMed documentation). Full-size machines like the AirSense 10 and 11 draw 7 to 9 watts. Adding a heated humidifier increases draw to 25 to 30 watts. Adding a heated tube pushes it to 50 watts or more. The power supply that comes with your machine lists the maximum wattage, but real-world draw during sleep is much lower than the rated maximum.