Hi Ultrapetita, Hi Geoffrey
yes it looks quit similar to your picture Ultrapetita, although i didn't use glue

It's noting more then a battery pack (costs about 50 cent) and a old USB extension cable i cutted and soldered to the pack. The input voltage of the GH-625 ist 4.6-5.6, so it works perfectly with my Eneloops... Of course one should be a bit cautious, if the NiMhs are coming right out of the recharger. Then they might have more then 1.45 V each, which could be a bit more the GH likes. But if one uses them after one or more days, the voltage will most likely be below 1.4, so no danger for the device any more. If one wants to be on the save sight, one could us a Zener-diode + resistor to cut away the peaks, but i think this is not neccessary in my case.
@ Geoffrey: I'll try again to sent you me request. So far i didnīt try to use solar panels directly to recharge the watch (to much regulation effort neccessary-no time and mood to solder around, no intention do by a comercial product, which is usually too heavy and expensive for me). Instead i use a small panel to recharge my NiMhs (unregulated) which i can use in many more devices then (headlamp, avalanche transceiver, PMR radio... and to recharge the GH-625

).
cheers
skeptisch