Lithium (either Lithium Ion or Lithium Iron Ferrite, the new kind) are really good for some applications, but I'd probably not use one in the '13 V7. First, they like to be warm - the colder it gets, the less cranking power they have, and when they hit a certain point they simply won't supply any power at all until they warm up. Second, they are not as good at cranking power unless you get a really good (read expensive) one. Read up on CCA equivalent ratings and you'll find out what I mean. Third, the V7 (and the earlier Breva) tends to have a bit of parasitic draw when parked - more than one might expect. LiIon / LiFe batteries don't really like being drawn way down, and they require a specialty charger; given the way the V7 behaves, I'd get a better quality AGM battery and a float charger/maintainer to get best possible battery life.
I'm not against LiIon / LiFe batteries - but they still have some way to go to be useful in all motorcycle applications. I had one in my Super Motard here in the desert and it worked great, but I wouldn't put one in my all-weather Norge, at least not yet.
