Poundland seem to be having the same experience that Pound World did when they started stocking power banks. Dead units out the box and unusually low capacities. Here's a look at two that fall into those categories.
Followup data. The low capacity one was drained and recharged and clocked in at 287mAh (supposed to be 1200mAh.)
The circuits have a disappointingly high quiescent current of 100uA (0.1mA) which means they are probably best used on an ongoing basis and not left in storage for too long.
I've been charging the completely flat cell for some time now and it's currently clocking in at over 1000mAh. Not sure how much of that is capacity and if any of it is internal self discharge. Also not sure how much of a risk this cell is having been completely discharged to zero. This is usually an issue with lithium cells and can cause "stability" issues.
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