I guess judging by the image Ichigo can absorb energy similar to what Ginjo did to him. I guess Kenpanchi didn't go because he was concerned with Ichigo's decision he just wanted to kill things. LOL. The battle ended kind of abruptly even with the captains confirming that Ichigo can take care of Ginjo.
I foresee a second transformation from Ginjo before it is all said and done. Ichigo seems way to relaxed for the battle to be over.