After tinkering with solar chargers and the like and not getting anywhere I have finally found a decent charger to power my Android phone.
I have used an Aldi solar battery pack for a while with mainly poor results. It worked kinda ok with my Blackberry but seems to suck power out of my Android. I find myself having to sit in my car for an hour at meets to charge up my phone as my 12v power point in my car is ignition fed.
Whilst browsing in Maplins I came across a pile of solar chargers from Power monkeys to own brand things. The problem with all these solar efforts is the output voltage, which is at best 500mv. I was approached by a staff member to see if I needed help and explained my problems with charging my phone. He immediately diverted my attention to one of these.
What a cracking bit of kit IMO. The output is 1000mv and it charges my Android as quick as the mains charger 3 times from about 20% to full.
Build quality is very good and it comes with a usb lead with interchangable bits (mini usb and micro usb) It charges via micro usb from your phone charger (min 1000mv) in 8 hours or via your usb on the pc in about 12 hours. All for less than £20 (just)
I don't use my phone much when in the woods so I can see myself getting 5 days use out of my phone using this gizmo.