Use blue eco to reach power cell was a mission that Jak and Daxter completed to obtain a power cell in The Precursor Legacy. An unassigned mission where Jak used blue eco to grab a power cell located on a far-away platform.
Enter Misty Island, proceed onto the main area and head right. Break the big rib bone here and get rid of any annoying lurkers, just in case. At the beginning of this area (where you broke the first bone) you can find a total of three clouds of blue eco. Grab each one and take a right, jump over the mud pool and the gap with the quicksand lurker and take another jump to your left (there's a babak here). Then jump onto the platform to activate it and take your ride to the power cell.