It’s alive !! Although with issues, right now (and in the picture) the battery is not charging, actually, for the system it is not present. I think the problem might be a fuse that burned, I as thinking that the power center was defective and was not providing enough power to charge the battery, but more probably the issue is with the fuse and the SMC is preventing the power to reach the logic board, then battery is not charging.
So, under normal operation the battery is not charging and the power supply is not providing any energy, how is that the computer is on?. No, is not on the leftover of the battery.