Batteries are an essential part of a portable CPAP machine. Most batteries last for around 8 hours each charge. The only difference between single and dual battery packs has to do with whether you want one or two CPAP batteries for your machine. If you plan to use your humidifier with your CPAP batteries, be aware that this causes the battery’s life to be cut almost in half. In this case, a dual pack may be the best choice. Consider, also, your lifestyle. If you travel often, you may want to invest in a dual pack of CPAP batteries because then you can rest assured that on a long flight, your CPAP machine will always be able to work. Purchasing a dual set of batteries also helps if you live in an area prone to power outages.
When looking at batteries, you need to see whether the batter uses AC or DC voltage. While most CPAP machines are able to use both AC and DC voltage, some require an adapter to convert the DC current to AC before the battery will charge the machine.