I need some help with my saturn

My sega saturn works fine except that all the internal memory is deleted when I turn off my saturn. I can save on it with no error, but once I turn it off, its gone. Also, everytime I turn on my saturn it asks for the time and date. It plays all games fine. its modded but it had the same problem before i modded it.

Any ideas on how to fix this?
i'm sorta a newbie with the saturn, is there a step-by-step instruction on how to replace it somewhere?

Or could someone type a really fast one? i could probably figure it out.
There is a cover on the back of the Saturn that pops out, sort of like a battery cover where the VCD player plugged into. Once you take this cover off you will see the battery. It pops right out. Slide the new one in and replace the cover. Play away.
hmm. I found the battery but I can't figure out how to slide it out. Is there a button you have to press or something?

sorry, i'm an idiot. =)