For those who know me even in the slightest, you'll know that I have a penchant for a decent torch. Those enlightened individuals will know that that the best bang per buck in terms of luminescence are the Cree led chips.
My fascination with flashlights started with a curiosity to see what night time off road cycling would be like. However the pre-requisite for this is having enough illumination to have enough fun and unfortunately the UK retail proposition runs into hundreds of pounds if you want a decent light output. So facing this problem I did what any rational person would - turn to Chinese ebay sellers. Sure enough they came through an a torch that is unbelievably bright together with a battery and charger for less than £10 posted!
Trouble is that you get supplied with doggily cheap batteries - you know the ones airlines are afraid of exploding or catching fire! Along with an equally looking dodgy charger with a non-UK plug which needs an adapter. I wouldn't have previously been bothered but after a spate of deaths some years back and the fact that two potentially suspect items will be used together I decided look for an alternative option.
My search didn't actually get far - I couldn't seem to distinguish what would be a reputable product or not. It was not until an unrelated search for a power bank I hit upon the solution.
The problem with power banks is the same with the Lithium Ion batteries which power the Cree flashlights - cheap Chinese batteries are just that cheap rubbish. Most over claim their capacities and you'll be looking to get a few uses out of them before their retained charge plummets and soon after that they stop working completely.
After my initial 18650 battery gave up the ghost I decided to invest in a reputable brand, this is actually harder than it sounds - the only one I could find is made by Uniross. After a bit of testing this little beauty is coming up trumps and is only a reasonable-ish £3.95
My hunt for a power bank started on Amazon, after a little bit of deliberation I decided to look elsewhere based on the mixed review. So next up was ebay. After endlessly trawling I came across this fella:
Bingo, this is what I needed - Specific details in the austion description were sparce though. were sparceA bargain at 99p.
My RaspberryPi2 lasted 4.5hrs running off the power bank.