I just recently purchased a battery grip. I have one Nikon EN-EL3e Rechargeable Li-ion Battery and another 3rd party battery the same type. When I use the battery grip it will not work when both batteries are in. If I take out the third party battery it works fine. Is this in issue with just this battery and if I have two Nikon branded batteries will it work fine? With a battery grip is just one battery in use and the 2nd simply for storage and you have to move over a slot? Please advise. Thanks