The new GE Active Keys are convenient and small and you don't have to use a cradle and connect to your computer to synch, they update via radio. However, the radio's aren't very efficient and will drag down the charge on the Active Key in a couple of days.
There are several solutions: 1) carry the Active Key in and place it on a home charger every day, 2) get a special car charger for your Active Key at a cost of over $20.00. 3) Use your existing cell phone automobile charger.
Yep, if you have a cell phone that charges via its USB port, you can use that same auto charger to keep your Active Key charge fresh. Whenever you are in your car and your charger is not plugged into your phone just go ahead and plug the charger into your Active Key. While you are traveling, your Active Key will be recharged and you will no longer be embarrassed to have your charge run out in the middle of showing multiple homes to your out of town buyers. And, if your vehicle has an accessory charging port that works even with the ignition off, your Active Key will be charging while you are in your office or at home. It will never have to leave your vehicle other than when you need it to access a lock box.
The pictures show both my phone and my Active Key connected, via USB port, to the same car charger that I picked up for $9.99 plus tax at Wal-Mart. I now only have one charging cord in my truck and both my phone and Active Key are charged at all times.