In the above picture and in the 1st backhand hit in the video linked, it looks like Robredo's backhand grip is either the extreme eastern or semi-western 1hbh grip - or something in between. That's more extreme than Gasquet's, Wawrinka's and Almagro's, who all use something of a standard eastern grip (Gasquet used to be more extreme).
However, in the subsequent backhands that Robredo hits in that video, if you pause it just before contact, he has shifted to a standard eastern. Perhaps, since the 1st backhand was very high he used a more extreme grip?
Downloading that video via KeepVid or something like it will help you to be able to pause it exactly when you want and go forward frame-by-frame (if you can be bothered).
Anyway, I'm quite impressed with Robredo's backhand during this mini-'comeback' of his. He has stated he thinks it's a weakness, but whilst he's not able/willing to go for it as much as his forehand, it is actually a safe, reliable against high balls, and heavy rally shot hit with a lot of topspin.