I have no idea, but can be helpful with advice on how to easily identify fakes and duds.
First, eBay. A seller to be trusted is Marj who sells genuine OEM Sanyo 18650 3500 mAh. I buy off her, she lives down the road from me and gets them from Europe. Fasttech China who are genuine are currently having shipping difficulties to the UK.
Anyway. LiIon cells leave the factory at a voltage suitable for storage. The above mentioned cells are at 3.47 volts, give or take about 0.1V, depending on storage time. However, if you buy several, the same batch should all read exactly the same. This condition is very difficult to engineer artificially by a seller of fakes or duds as it would be impossible to get the charge levels all exactly the same, and they would loose uneven amounts of power in transit, such is the nature of junk cells. Once they have had the first time charge obviously this condition has gone and the only hint would be to test them fresh off charge, then again after say a week to see if any loss. After charge, good cells will, 'settle' so to speak, we are talking though about 0.01 volts.
Apart from this I cannot help with the above, but obviously seller feedback could give indication.