On a Dell R710 server running Window Server 2008 R2 there are currently 4 50GB SSDs in a RAID 10 array, and I'm adding 2 additional 50GB SSDs. This server runs SQL Server and not much else. If these were spindled HDs, from what I've read I would be better off to create a new VD dedicated to the DB logs and temp DB. Since the entire system is SSDs, though...I don't know if it really matters? It will certainly be easier to create a new VD. It seems that PERC 6/i RAID 10 arrays can't be expanded by adding new drives? That means I'd have to backup, create delete and create a new VD with all drives, and restore. I think. I'm primarily a programmer, and not a server admin.
The PERC 6/i is capable of online capacity extension. You should be able to use the OpenManage Storage Management GUI to "Reconfigure" your virtual disk, take a look at the docs specific to your version for the "how".
If you indeed would need to bother with an extension or rather create a new VD is an entirely different question. Even with SSDs you might want to isolate I/O so your database log ops are not starving out other I/O (or your other I/O not starving out the log I/O, depending on the constellation). On the other hand, you probably add the new drives because you need the capacity - it probably would be easier to use when it is part of the currently configured volume. Whatever reason outweighs the other one would be up to you to decide since it is quite specific to your situation.