Generic batteries and the battery grip- problem?

I decided to pick up a battery grip for the OM D EM5 today but when trying it out prior to purchase i discovered that the two batteries i had bought off ebay , while they function well in the camera must be ever so slightly bigger than the original battery as when I tried to use one in the grip it would not eject, locked in tight as a drum , the lad assisting had to use a piece of tape inserted into the small gap to get enough purchase to eject the battery

After all that i never actually used it with the aftermarket battery only with the original .

With the current price of original batteries at $99+ I decided i was not keen on buying the grip after all and left it in the shop

anyone else tried the grip with non Olympus batteries and encountered this problem? I suspect they would work OK I was just not keen on having to go through this process every time I wanted to remove or change batteries in the grip.

thought other folks considering the purchase of a grip might like to know of this possible problem and also see if anyone has a work around, I suspect shaving some of the battery casing off is not a good idea

Ron

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Ron Co