I found my old PJB100 car charger thingy. Perhaps with this information, someone can confirm whether it's compatible with the iHP series.
HanGo electronics co ltd
Model: JBA-100
Manufacturer: LEAD Technology
INPUT: 13.8VDC
OUTPUT: 5VDC, 2A
FUSE: 250V, 2.5A
I vaguely remember a friend saying that it works with the iHP but am not prepared to recommend it without further backup
