When you're going into eclipse without a battery, what difference would it make if you could? :-)
But, this post is about a different question... As the spacecraft tumbles in direct sunlight, I understand that there are some orientations it might tumble through that result in not quite enough power to run everything. First, is that correct? And, if so, what choices can the IHU make in terms of lightening the load on the solar panels? I presume the tumble would be slow enough that you could see the power dip coming... Can the various downlink components, the university experiment, etc. be independently shut down?
If the ARISSat-1 satellite goes into eclipse, and the battery has failed, the software doesn't get to decide when to shut down. The lights are out with no power.