It Happens To Everybody Eventually - Hahnel
You may leave it behind at the hotel when you check out - that is where hotel concierges get their supplies - or you may leave it in the drawer at home. That is the same drawer that makes your car keys and glasses vanish. Wherever it was, it isn't now, and will never be again.
Solve the problem by getting a Hahnel Unipal universal charger. It has input from the mains, from a cigar lighter in the car, and from a USB port. It outputs to any number of batteries - there are two movable blades to supply the positive and negative to whatever battery you slide in there. You can even charge up the AA and AAA types of battery as well.
To monitor the progress of the charge, there is a tiny little LCD screen with a diagram of percentages - the charger will analyse how much is in the battery to begin with then report as it fills up.
We use them ourselves here in the shop to cope with the multitude of batteries of different sizes from all the cameras. For $ 69,95 you are saved.
Note: it will not recover your car keys, glasses, or the matching sock that you need. You're still in trouble...