By the way I can't seem to find the correct tesseract description.. the ones on the wiki seem to say they only transfer 100 mj/t but they look differently from the one I have and I tested mine they transfer 40k mj/t easily. At least I didn't test them with anything higher. I was kinda curious though is that true that they lose 25% power? Or are the ones in ftb infinity don't do that?
That... is terribly old information, from Thermal Expansion 2 for Minecraft 1.4.7, when there were different Tesseracts for Items, Fluids, and Energy. The Thermal Expansion 4 Tesseract for 1.7.10 can handle all three of these things, and has no energy loss. Their maximum capacity: I'm not sure. It used to match the transfer rate of a Resonant Energy Cell at maximum output, per side, but that may have changed since 1.6.4.