Charging CPAP battery with universal car adapter

[toedragon]

I have a Respironics CPAP and recently found out about a battery pack that can be attached to the device. You can purchase the battery with a car charger for $25, but I have a couple of other devices that I bring with me on trips that I sometimes charge as well, so I was thinking that I might get an adapter to convert to a standard AC plug-in, like this. Does anyone have any experience with an adapter like that? Will it be strong enough to charge a CPAP battery while driving? The system specs on the battery say "Charge Current:2.3 Amps" if that makes any difference.

[yrnkrn]

It's more efficient to directly charge your battery from car lighter socket using the car charger instead of converting the car voltage to 110V and back to 12V again.

[Gadget_OSA]

A charge current of 2.3A at 12V is nominally a 12 x 2.3 = 27.6watt load. The actual wattage will be a little higher than this. The inverter you linked to on amazon is rated to 175watts so it should handle the battery charge application no problem. I note that amazon descibes the inverter as 12V AC to 110V DC. I figure this should be 12v DC to 110V AC.

[toedragon]

Cool, thanks for the response.