Awesome, my gps charger charges my apache! Question

[Torx]

okay, so ive been going without a car charger for my apache forever.. and here lately battery power has been a slump... so the other night i thought about building a battery powered usb charger for the phone.. then i thought, we hmm i should just go ahead and buy a car lighter adapter with 2 usb ports on it, so i did for $8 total shipped on ebay.

then tonight i realized my holux gps car charger cable end fits the apache, plugged it up and, ding! i was on a charge.

even though the car charger adapter states a 5v out, it doesnt say anything about mah output. The lipo battery in the holux is 850mah i believe.. Could i do any damage to the apache?