Like most modern devices, the 817 has a simple press button for power on and off rather than a mechanical switch - that kind of arrangement will always have some residual current drain while off - usually measured in micro-amps rather than milli-amps. My 817 spent at least a year without being charged and the batteries still hold a useful amount of charge - can't tell you what capacity is left, but it is certainly not destroyed. That said, I use AA NiMH batteries in the dry cell case, not a composite battery pack.
Martin (G8FXC)
