Recently bought a nex-6, and the included battery shows the amount of charge remaining on the display during normal use. Just bought another Sony battery off Amazon, and it does not show this (just a crossed-out battery icon). The new battery seems to charge and operate normally, but part of the reason I paid the extra for the Sony battery was to ensure that the remaining charge would be shown. The new battery that does not show the percentage is later alphabetically than the original (old:k2hhe, new:k3egh). It does not appear to be counterfeit, as the new one looks identical except for the different code. How do I ensure that any replacement battery I exchange this one for will not have the same problem?