Battery Powered CPAP Machines
By Andrew Senske, President CPAP-Supply.com
Last Updated 08-05/2007 09:43:00 PM
Many of the sleep apnea machines we sell have a 12V input that allows them to be powered by a 12V battery. Having the ability to run your machine from a battery can be useful for traveling and it can also come in very handy during a power outage. In this article I'll cover the different aspects of battery powered CPAP machines and give some recommendations for different scenarios.
The AEIOMed Everest and integrated battery - released late 2005 / early 2006 - is a unique CPAP system in that it is the first CPAP machine designed to work with an integrated, proprietary battery that connects directly to the CPAP machine. There are a couple of key advantages to the AEIOMed Everest CPAP system, although these advantages come at a fairly steep cost.
First, the optional integrated Everest Battery is very lightweight at about 1.5 pounds. This is in sharp contrast to the more common, large, car-battery-type 12V batteries that aren't easily hauled around on camping trips, and look fairly odd as part of your bedroom decor. These big batteries work, it's just that their form factor leaves something to be desired.
The second big advantage of the Everest system is redundancy. That is to say, when the battery is connected to the Everest CPAP machine while the machine is being powered from a wall outlet, the battery acts as an automatic backup in case of a power outage. This is a feature which really differentiates the Everest CPAP system from all other battery configurations with which I'm familiar. To know that even during a power failure the CPAP machine will continue providing therapy without interruption lends peace of mind to many CPAP users. With other battery configurations you'll still be able to power your CPAP machine from a battery, but the difference is that you'll have to wake up and hook up the CPAP machine to the battery.
Finally, the Everest Battery actually looks like part of the CPAP machine. It doesn't necessarily look like you've got a battery hooked up to your CPAP machine. I liken this difference (to other battery configurations) to the difference between an iMac and PC. PCs work great most of the time, but they look big and clunky and many are borderline ridiculous in size, whereas iMacs are compact and cool looking. If aesthetics is meaningful to you, then this point should be considered.
It's likely though, that you either already have a CPAP machine or that you don't feel like shelling out big bucks for a proprietary battery like the Everest. It may also be that you're looking for an automatic machine, so the Everest CPAP system with the Everest Battery just doesn't meet your needs. If that's the case, and you still want to use a battery with your CPAP machine, then keep reading.
As I mentioned earlier, most newer CPAP machines have 12V inputs which means that many of the CPAP machines we sell can be powered by a 12V battery. To power your CPAP machine from a 12V battery you'll only need two items that weren't included with your CPAP machine. The first item is the 12V cord that is designed for your particular CPAP machine. We sell the 12V cords for all the CPAP machines we sell. You can find them in the CPAP Accessories - Machines Cords & Cables section of our web site. You can typically choose a 12V cord with a cigarette lighter plug that connects to a 12V outlet, or a 12V cord that connects to the red and black (or plus and minus) battery terminals on the battery.
The 12V cords for different brands aren't interchangeable. For example, the 12V cord for the GoodKnight 420G doesn't work with the Respironics REMstar M Series machines, because the size of the 12V inputs on the CPAP machines are different. If you have any questions about which 12V cord to purchase, you can give us a call and we'll be able to help you find the cord you need quickly.
The second item you need, of course, is the battery. Unless you've decided on the very handy AEIOMed Everest CPAP system, then you'll need to purchase a stand-alone battery. If you have a battery store in your town you could go there and tell them your requirements to see what they recommend. The key to choosing the right battery is knowing the power consumption of the CPAP machine along with identifying your needs in terms of duration - or how many nights you need the battery to last. Note that the power consumption of a typical CPAP machine is about 20 Watts. If you want to know this number for your CPAP machine, look at the label on the bottom or the back of the machine and multiply Volts and Amperes. That will give you the power consumption. Also, if you go to a local battery store you might want to take the CPAP machine with you.
If you're looking for just one night of battery use before the battery needs to be recharged, then many 12V batteries will work for you. I've heard from a few customers that they use the Black & Decker Simple Start. This is a battery designed to be an emergency car starter, and from what I've heard it will easily power a CPAP machine for a night. The nice thing about the Simple Start is that it's relatively small and lightweight - it fits in a glove box and is about 5 pounds - and it has a 12V outlet into which you can plug your 12V cord. With this type of battery there's no need to connect a cord directly to battery terminals. Another key point is that this particular battery is only about $60, far less than the $236 price tag currently on the AEIOMed Everest battery.
As far as redundancy during a power failure goes, you won't get it with a standalone battery the way you will with the Everest. However, you could always get an uninterruptible power supply or UPS - typically designed for computers - and plug your CPAP machine into that. Then, if the power goes out, an alarm on the UPS will alert you to the fact that you need to hook up your stand-alone 12V battery. Otherwise, you could just assume that an apnea will wake you up eventually!
If you need more than a single night of battery use then your best bet is probably a deep cycle marine battery. This is where your local battery store will come in handy. I don't know a whole lot about deep cycle batteries, except that they're generally bigger, heavier, more expensive and they can power a CPAP machine for 3 or 4 nights before needing to be recharged.
If you plan to use a humidifier with a battery you should also plan on not using heat. Turning on the heat will increase power consumption and significantly decrease battery life. The good news is that you can always use your heated humidifier with the heat setting turned off. Perhaps not the best solution, but better than no humidification at all.
I'd really be interested to hear your own personal recommendations for CPAP battery configurations. Feel free to call or email us anytime with your input.
CPAP-Supply.com is a leading online retailer of CPAP equipment. Located in Spokane, WA CPAP-Supply.com has been serving thousands of customers around the world since 2001. Founded on a belief that patients are their own best primary care providers, CPAP-Supply.com understands the importance of educating patients and customers on both the effects of and treatment for obstructive sleep apnea. For more information visit CPAP-Supply.com or call toll free 1-888-955-2727.