A CPAP battery typically runs a machine for 1 to 3 nights (roughly 8 to 15 hours) on a single charge, depending on the machine, humidifier, and pressure setting. ResMed puts its own devices at up to 13 hours per charge. [3] This guide covers battery life, how to calculate your own runtime, what drains a battery fastest, the difference between a travel battery pack and a power station, and how to power a CPAP during a flight, camping trip, or blackout.
At a Glance
- Typical runtime: 1 to 3 nights, up to 13 hours per charge on ResMed devices. [3]
- Runtime formula: hours = battery capacity (Wh) / CPAP power draw (roughly 30 to 70 W, varies by model and pressure).
- Biggest drain: a heated humidifier or heated tubing, then a high pressure setting, according to Ozzy, one of our respiratory therapists.
- Flying: up to 100 Wh needs no approval; 101 to 160 Wh needs airline approval. [1] Our guide to flying with a CPAP has the full walkthrough.
- Two shapes: a lightweight travel battery pack (1 to 2 nights) or a rugged portable power station (multiple nights, off-grid).
How Long Does a CPAP Battery Last?
Most CPAP batteries run a machine for 1 to 3 nights, about 8 to 15 hours, on a single charge. ResMed says its external batteries deliver up to 13 hours per charge and recharge in about 4 hours. Your real runtime depends on the machine, whether the humidifier is on, and the pressure setting. [3] [4]
- ResMed's own figure: an external battery powers the device "up to 13 hours," and roughly 4 hours of charging gives up to 13 hours of battery life. [3] [4]
- Field example, travel machine, no humidifier: an AirMini AutoSet at 10 cmH2O on a Zopec Explore Mini ran about 15 hours, nearly two nights, according to Uncle Nicko of CPAP Reviews.
- Field example, full-size machine, humidifier off: a ResMed AirSense 10 or AirSense 11 with the humidifier off ran about 10 hours on the same battery.
- Field example, power station: the CPAP Battery Bank EXP96PRO APEX runs 4 to 6 nights on a charge with no humidifier or heated tubing. Lilly Perez, one of our respiratory therapists, puts it this way: "The big one can last you four to six days."
- The honest caveat: exact runtime is not one number. The next two sections below cover the wattage math and the factors that move it.
"If I was to run this AirMini here 10 cm of pressure on a Zopec Explore Mini, it's going to last around 15 hours so nearly two nights on a single charge. Now by comparison, if I was to run the AirSense 10 or the AirSense 11 even with the humidifier off, we're looking at around 10 hours from a single charge."
— Uncle Nicko, CPAP Reviews, on the Sleeplay channel
How Many Watts Does a CPAP Use? How to Calculate Your Runtime
A CPAP machine without a heated humidifier typically draws roughly 30 to 70 watts, depending on the model and pressure setting. To calculate your own runtime, divide the battery capacity in watt-hours by the CPAP's power draw in watts: Runtime (hours) equals Wh divided by W. Heated humidifiers and higher pressure raise that draw.
- The formula: Runtime (hours) = battery capacity (Wh) / CPAP power draw (W).
- Power draw: roughly 30 to 70 W, depending on model and pressure.
- Direct DC power: a cable straight from the battery to the machine is more efficient than running the machine through an AC inverter to get standard AC power.
- Humidifiers and heated tubing: these are the biggest single drain, and many batteries will not power the heater at all. Our CPAP humidifier guide explains how humidification works, and also our guide on how a CPAP machine works covers the power basics.
Treat the table below as a worst-case floor, then use the field examples in section 1 above for a realistic expectation. Most machines draw well under 70 W without a heated humidifier.
| Battery | Capacity | Estimated range at 30 to 70 W |
|---|---|---|
| Transcend PowerAway | 71 Wh | about 1.0 to 2.4 hours |
| Medistrom Pilot-24 Lite | 95 Wh | about 1.4 to 3.2 hours |
| Medistrom Pilot Flex | 98 Wh | about 1.4 to 3.3 hours |
| Zopec Voyage Universal | 146 Wh | about 2.1 to 4.9 hours |
| Freedom 160 | 160 Wh | about 2.3 to 5.3 hours |
These are formula-based, worst-case estimates at the top of the power-draw range. Real-world runtime is usually longer, since most machines draw under 70 W without a heated humidifier. ResMed's "up to 13 hours" and the 10 to 15 hour field tests above reflect that more typical draw.
What Drains a CPAP Battery Fastest?
The biggest drain comes from heated comfort settings like a heated humidifier or heated tubing, which many batteries cannot even power. A high pressure setting is next. Ozzy, a Sleeplay respiratory therapist, adds that the machine model, how many hours you sleep, and a hot climate all change how long a battery lasts.
- Which machine you have: each CPAP model pulls a different amount of current.
- Humidifier and heater: running the heater drains a battery fast, and most batteries will not support it. Turn off the humidifier heater, use a waterless HME, or use a machine like the AirMini with its own low-draw humidification before running on battery. Our ResMed AirMini review covers how that works.
- How many hours you sleep: a longer night needs more capacity.
- Weather and temperature: a hot climate raises a battery's discharge rate, so a pack that lasts about 10 hours on a cool night might last only about 6 hours in hot sun.
- Pressure setting: higher pressures, in the 16 to 19+ range, drain a battery noticeably faster than lower pressures.
"Battery run times can vary greatly depending on a multitude of factors. It all depends on the weather conditions. It depends on how charged the battery is, and it depends on your CPAP pressure. If you have a higher pressure, the machine, the batteries will tend to last less."
— Oswald Azua ('Ozzy'), Respiratory Therapist, Sleeplay
CPAP Battery Types: Lithium-ion vs Deep-cycle vs LiFePO4
Most CPAP batteries sold today are lithium-ion: light, compact, and flight-friendly. Deep-cycle batteries trade portability for longer raw runtime and suit camping or RV use. LiFePO4 (lithium iron phosphate), used in Sleeplay's EXP PRO line, is the longest-lived lithium chemistry, which is why power stations rely on it.
| Type | Portability | Runtime style | Flight-friendly | Sleeplay example |
|---|---|---|---|---|
| Lithium-ion (standard) | Light, compact | 1 to 2 nights typical | Yes, most models under 100 Wh | Pilot Flex, Pilot-24 Lite, PowerAway |
| LiFePO4 | Slightly heavier, still portable | Longest-lived lithium, multi-night | Depends on the Wh rating | EXP48PRO / EXP96PRO APEX |
| Deep-cycle | Heaviest, bulkiest | Longest raw runtime | Not built for carry-on | Best for home standby or RV; ask a Sleeplay specialist |
- Lithium-ion (standard): light, compact, quick to charge, and the modern default for travel batteries like the Medistrom Pilot Flex and Transcend PowerAway.
- Deep-cycle: heavier and bulkier, built for camping, RV, or home standby use, and not designed for air travel.
- LiFePO4 (lithium iron phosphate): the longest-life lithium chemistry, used in Sleeplay's EXP96PRO APEX and EXP48PRO APEX power banks. The smaller one lasts about 48 hours, and the larger one lasts 4 to 6 days per charge, according to Lilly Perez.
"LiFePO4, which means lithium iron phosphate, which is the best, longest, most environmentally friendly lithium battery that you can use. The little one can last you 48 hours and the big one can last you four to six days."
— Lilly Perez, Respiratory Therapist, Sleeplay
Battery Pack vs Portable Power Station: Which Shape Do You Need?
A travel battery pack is light and flight-ready, built to run a CPAP for one or two nights. A portable power station is heavier and more rugged, built to provide adequate backup power for a machine plus a fan, lantern, or phone for multiple nights off the grid; the EXP96PRO APEX runs 4 to 6 nights. Weight always trades against runtime.
| Feature | Battery pack (travel) | Portable power station |
|---|---|---|
| Weight | About 1 to 1.5 lb | About 3.5 to 6.5 lb |
| Example | Pilot Flex (1.2 lb), PowerAway (16.7 oz) | EXP48PRO APEX (3.5 lb), EXP96PRO APEX (6.5 lb) |
| Runtime style | 1 to 2 nights, CPAP plus USB devices | Multiple nights (EXP96PRO: 4 to 6 nights, no humidifier), also runs a fan, lantern, or phone |
| Flight-ready | Yes, most under 100 Wh | Built for off-grid and outages, not flights |
| Best for | Flights, hotels, short trips | Camping, hurricane season, extended outages |
Two categories, in Daniel Feldman's words: 'integrated backup batteries' for home outages versus 'travel CPAP batteries,' lightweight, portable, FAA-approved, and 'made for life on the go.'
- Travel pack example: Medistrom Pilot Flex, 1.2 lb, 98 Wh, charges in 2 to 3 hours. [6]
- Power station example: CPAP Battery Bank EXP96PRO APEX, 6.5 lb, LiFePO4, 4 to 6 nights, recharges in about 8.5 hours, IP65 dust- and water-resistant. [10]
The tradeoff: it is always weight for runtime. The lighter the pack, the fewer nights it covers before you need to recharge. For camping specifics, see camping with your CPAP.
"Well, we've got two main options for you. First option, integrated backup batteries. These are built into your machine or setup, and they've got your back during any home power outage. Then you've got your travel CPAP batteries. Lightweight, portable, FAA approved, and made for life on the go."
— Daniel Feldman, Sleeplay team
Which CPAP Battery Do You Need?
Match the battery to three things: how many nights you need off the grid, whether you want solar charging, and which CPAP machine you run. One night favors a light pack like the Medistrom Pilot Flex; three or four nights favor a power station like the EXP96PRO APEX.
Daniel's three questions make a good starting point: how many nights off the grid, do you need solar charging, and what is your CPAP machine? Make sure the battery is compatible, or grab the right DC adapter cable. Prices below are regular Sleeplay prices, checked September 17, 2026.
| Power need | Recommended pick | Why |
|---|---|---|
| One night, flying or hotel | Medistrom Pilot Flex, $339 | Under 100 Wh, no airline approval, 2 to 3-hour charge |
| One night, ultralight | Transcend PowerAway, $349.95 | Lightest option, solar-chargeable |
| Multi-machine, long-haul | Zopec Voyage, $540, or Freedom 160, $349.99 | 101 to 160 Wh band, 3 to 5 nights, universal compatibility |
| 3 to 4 nights off-grid | EXP96PRO APEX, $499 | 4 to 6 nights, LiFePO4, rugged |
| Home outage / UPS | EXP48PRO, $399, or EXP96PRO APEX | Runs instantly when wall power drops |
| Want solar on the trip | Transcend Solar Charger, $259 | Foldable, no wall outlet needed |
- One night, flying or a hotel: the Medistrom Pilot Flex ($339) is 98 Wh, FAA-compliant, 1.2 lb, and charges in 2 to 3 hours with a 45 W USB-C charger. ResMed AirSense 11 users can add the Pilot Flex Cable Kit for AirSense 11 ($18).
- One night, ultralight, Transcend machines: the Transcend PowerAway ($349.95) is 71 Wh, 16.7 oz, and solar-chargeable.
- Multi-machine or long-haul (needs airline approval): the Zopec Voyage Universal ($540) is 146 Wh. The Freedom 160 ($349.99) is 160 Wh, lasts 3 to 5 nights, and works with ResMed, Luna TravelPAP, Transcend Micro, and Philips DreamStation.
- For 3 to 4 nights off-grid or camping: the CPAP Battery Bank EXP96PRO APEX ($499) offers 4 to 6 nights, uses LiFePO4, and is IP65-rated. The lighter EXP48PRO APEX ($399) is the 3.5 lb sibling.
- Want solar on the trip: the Transcend Portable Solar Battery Charger ($259) is foldable, under 2 lb, and pairs with the PowerAway.
You can see the full lineup in CPAP Batteries and Battery Power Solutions. For a full side-by-side buying comparison of every model, read our Best CPAP Batteries guide.
"How many nights off the grid do you need? One night, go light. Three or four nights, you'll want the EXP 96 Pro. Do you need solar charging on the trip? What's your CPAP machine? Make sure your battery is compatible or grab the right cable from Sleeplay."
— Daniel Feldman, Sleeplay team
Can You Run a CPAP During a Power Outage?
Yes: a CPAP battery backup can act as a UPS (uninterruptible power supply) during a power outage. Uncle Nicko (CPAP Expert) demonstrates on the Sleeplay channel how to run the machine off a battery so it takes over instantly when the power drops. A power-station-style battery like the EXP96PRO APEX can run a CPAP for 4 to 6 nights without a humidifier.
- The UPS setup: keep the battery's fast charger plugged into the wall while the machine runs off the battery. If the power drops, the battery takes over instantly with no gap in therapy.
- Longer outages: batteries can also run in series for double the runtime, according to Uncle Nicko.
- Storm season: for a full plan, see our CPAP hurricane and power-outage plan.
- Recommended for outage duty: the EXP48PRO or EXP96PRO APEX, built for multi-night, no-humidifier runtime. You can also browse Battery Power Solutions.
"Now I'm running this as a UPS and if that hurricane comes in the middle of the night and power goes out, this will continue to run the AirSense 11 so I'm not disturbed."
— Uncle Nicko, CPAP Reviews, on the Sleeplay channel
How Do You Power a CPAP Without Electricity?
Without an AC outlet, a CPAP can run on a portable lithium-ion or LiFePO4 battery, or a deep-cycle battery for longer off-grid use. Daniel from Sleeplay frames the choice as two categories: integrated backup batteries built into your setup for outages, or lightweight, FAA-approved travel batteries. Solar panels can recharge either type during the day.
How to Charge a CPAP Battery: Wall, Car, Solar
Every Sleeplay battery charges from a wall outlet with its included charger; most also charge from a car's 12-volt port or a foldable solar panel through a USB-C or DC input while powering your machine via a DC output. The Medistrom Pilot Flex reaches a full charge in 2 to 3 hours; a power station like the EXP96PRO APEX takes about 8.5 hours.
- Wall: The included charger is the default and fastest method. The Pilot Flex takes 2 to 3 hours with a 45 W USB-C charger, and the EXP96PRO APEX takes about 8.5 hours.
- Car: a 12-volt cigarette-lighter-style DC charger or a USB-C PD car charger works while you drive to a campsite, according to Uncle Nicko.
- Solar: a foldable panel charges through the battery's USB-C or DC input, so you don't need a wall outlet. The Transcend Portable Solar Battery Charger ($259) is built for the PowerAway.
- Maintenance: unplug charging cables when you're not actively charging. From our review of the Pilot-24 Lite: "any cables that you leave connected will drain the battery even if it's not connected to your machine, even if your equipment is off, even if you're not using it."
The Bottom Line
A CPAP battery gives you 1 to 3 nights of therapy, and the right one depends on how many nights you're off the grid, your machine, and whether you fly. Prices below are regular Sleeplay prices, checked September 17, 2026.
- Best for the occasional flyer: Medistrom Pilot Flex ($339), under 100 Wh, no airline approval needed.
- Best for a single off-grid night (ultralight): Transcend PowerAway ($349.95), which pairs with the Transcend Solar Charger ($259).
- Best for 3 to 4 nights off-grid or a hurricane-season outage: EXP96PRO APEX ($499), or the lighter EXP48PRO APEX ($399).
- Best for a long-haul or multi-machine household: Zopec Voyage ($540) or Freedom 160 ($349.99), both 101 to 160 Wh, with airline approval to fly.
Ready to compare every model side by side? See our full CPAP battery buying guide, or browse CPAP Batteries. Questions about your setup? Chat with a Sleeplay specialist.
Frequently Asked Questions
How much do CPAP batteries cost?
Battery prices vary widely. Light options like the Transcend PowerAway run $349.95 and the Medistrom Pilot Flex at $339. Power station options for extended use include the CPAP Battery Bank EXP96PRO APEX at $499 and the lighter EXP48PRO APEX at $399. Prices checked September 17, 2026. Solar panels and machine-specific cable kits are sold separately.
Should I leave my CPAP plugged in all the time?
Yes, at home run your machine on wall power and save the battery for travel, camping, or power outages. Unplug charging cables when the battery is not actively charging, since a connected cable drains the battery even when the machine is turned off.
What is the 4-hour rule?
The 4-hour rule is a Medicare compliance standard, not a battery specification. The Centers for Medicare and Medicaid Services requires at least 4 hours of CPAP use on 70 percent of nights during a consecutive 30-day period in the first 3 months of therapy for the device to remain covered. It has nothing to do with battery life or capacity.
Can I run my CPAP off a battery?
Yes. Portable lithium-ion and lithium iron phosphate battery packs and power stations deliver clean, pure sine-wave power to run CPAP, BiPAP, and APAP machines through a direct DC cable connection, which is more efficient than using an AC inverter.
Does insurance cover a CPAP battery?
Usually not. Most insurance plans and Medicare treat a backup or travel battery as an optional accessory rather than durable medical equipment, so coverage is inconsistent and most buyers pay out of pocket. Check your specific plan, since payer policies vary significantly.
Are CPAP batteries safe to use every night?
Yes, when sized and charged correctly. Lithium-ion and lithium iron phosphate battery packs use the same chemistry as phones and laptops and include built-in charge protection. However, you do not need to use the battery nightly if you have reliable wall power at home. Save the battery for travel, camping, or power outages instead.
How do I store a CPAP battery when it is not in use?
Store it partially charged, not completely empty and not fully charged, in a cool, dry place. Disconnect any charging or machine cables, since a connected cable drains the battery even when the machine is off. Check the charge level every few months and recharge if needed.
Can I charge a CPAP battery with solar?
Yes. Several CPAP batteries pair with foldable solar panels via USB-C or DC input, so you do not need a wall outlet. Options include the Transcend Portable Solar Battery Charger built for the PowerAway, and similar solar charging solutions designed for travel and camping.
What size CPAP battery do I need?
Match the battery size to how many nights you will be off the grid, your humidifier use, and your machine type. For a single night, choose a light pack like the Pilot Flex. For three to four nights or extended use, step up to a multi-night power station like the EXP96PRO APEX.
Will a CPAP battery switch over automatically during a power outage?
With the right setup, yes. Keep the battery's fast charger plugged into the wall outlet while your machine runs off the battery. When wall power drops, the battery takes over instantly with no interruption to therapy.
References
- Federal Aviation Administration. PackSafe: Lithium batteries (100 Wh no-approval limit; 101 to 160 Wh with airline approval, max two spares; carry-on only; removal from gate-checked bags). https://www.faa.gov/hazmat/packsafe/lithium-batteries
- Electronic Code of Federal Regulations. 49 CFR 175.10, Exceptions for passengers (lithium ion battery Watt-hour limits). https://www.ecfr.gov/current/title-49/subtitle-B/chapter-I/subchapter-C/part-175/section-175.10
- ResMed. "Should I get a CPAP battery?" (external battery powers a device up to 13 hours; about 4 hours of charging). https://www.resmed.com/en-us/sleep-health/blog/should-i-get-a-cpap-battery/
- ResMed. "CPAP batteries and adaptors" (charging and adaptor guidance; up to 13 hours). https://www.resmed.com/en-us/sleep-health/blog/cpap-batteries-and-adaptors/
- Centers for Medicare and Medicaid Services. Local Coverage Determination L33718 (the 4-hour, 70 percent adherence standard). https://www.cms.gov/medicare-coverage-database/view/lcd.aspx?lcdid=33718
- Medistrom / Pilot Flex. Product specifications (98 Wh, FAA compliant, 2 to 3 hour charge with a 45 W USB-C charger, 1.2 lb). https://www.pilotflex.com/features
- Medistrom. Pilot-24 Lite specifications (95 Wh, 24V ResMed compatibility, charge-cycle count). https://www.medistrom.com/products-pilot24-lite.html
- Transcend (Somnetics). Micro PowerAway battery (71 Wh, solar-chargeable). https://www.mytranscend.com/products/transcend-micro-poweraway-battery
- Zopec. Voyage Universal battery, air travel page (146 Wh, automatic 12 to 24 Voltage). https://www.zopec.com/pages/voyage-battery-air-travel
- Sleeplay product pages (verified 2026-09-17): Freedom 160 (3 to 5 nights), CPAP Battery Bank EXP96PRO APEX (6.5 lb, 4 to 6 nights, LiFePO4, IP65) and EXP48PRO APEX (3.5 lb), Zopec Explore Mini (under 100 Wh, built-in UPS). https://sleeplay.com/collections/cpap-batteries
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