At the beginning of Shippuden, Kakashi uses Mangekyo Sharingan: Kamui to teleport Deidara's bombs so it doesn't go off in their faces but Kakashi is then bedridden for a week because using Kamui takes a huge toll on him and sucks up all his chakra. Kakashi also said he could only use his Chidori five times a day at the very most.
After Madara and Obito start the Ninja War, all of a sudden Kakashi can spam Kamui and Chidori and literally nothing happens. I get that Kurama lent him chakra, but Kakashi was spamming stuff way before that aswell, and besides, Kurama didn't give him that much chakra.
So how can Kakashi use Kamui and Chidori so much during the Ninja War when before it was apparently so taxing to him?