OK, let's clear this up. Sorry to contradict you Causidicus, but your info is unfortunately incorrect.
I am 100% certain about the following having spoken with the guys at Campagnolo in Italy.
1) You definitely need a V2 charger.
2) You don't necessarily need a V2 interface unit, but you might want to buy one for 2 reasons. Other than these 2 reasons, it will function perfectly well. Firstly, since the diagnostics will no longer be housed in the battery because it is hidden in the frame, the diagnostic LEDs are now housed in the V2 interface. You can therefore either forgo the onboard diagnostics and not buy a V2 interface, or you can benefit from the onboard diagnostics and buy a V2 interface. Diagnostics will still be available by plugging a computer into the V2 battery, it is just that the battery itself won't have the LEDs. The V2 power connector also has a data stream, not just power. In reality, the V1 diagnostics simply showed where in the system the problem was, not specifically what the problem was, or how to fix it. Its use was therefore limited anyway. Secondly, to benefit from the new software changes you need the V2 interface unit. There have been some problems with the early front mechs losing their memory and over shifting and the distance by which the rear mech over shifts slightly to shift gear is variable in V2 depending on which cog you are in at the back which the firmware fixes solve. You cannot simply update the software on the V1 interface (as I pointed out in a previous post, this is one of the areas where V2 EPS lags behind V2 Di2). If you haven't experienced problems, you might not want to bother. I personally have not, and for what a new interface will cost, I am at least going to try not replacing it at first.
4) With regards to the charging status, the V1 interface will still show the charging status through a series of green and red LEDs using the existing functionality, just as it currently does. Also, since the trigger to stop charging is housed in the charger itself, there will be no loss of function by not buying a V2 interface.
Good post Solarider. I had the charge and diagnostics mixed up. I spoke again to the tech guy at campy canada and he said exactly what you said.
He confirmed that you need a new charger for the new battery. They still haven`t received the new battery as it hasn`t shipped yet. As soon as they get them, he will try the old interface with the new battery.
A good improvement on the new battery is that you can now adjust individually the front derailleur for the big and small chainring. The old battery you can`t do that.
Its gonna be a nightmare for some shops installing the new battery internally. need to buy more tools, etc... I can`t believe they didn`t think to put a charge port on the new interface.