If you own the plane it's worth fitting the dedicated aircraft-power socket; Aircraft Spruce sell them for about $30. Headset Services sell them for rather more I believe
Then you don't need batteries. The only drawback of that is that the headset can't be used in another plane, and won't plug directly into an Icom transceiver's headset adaptor. The latter reason is why I keep an extra headset (with the normal jacks) for use with the Icom.