The SC150 is a great scanner, I used to have one. I'd say the battery pack is completely shot. Go to Batteries Plus, they probably have replacements for it. If not, they should be able to make one for it.
You would probably be better off asking what you can hear with it in the MN forum. Not sure where you are in the Metro, but you can still hear quite a bit of action with a regular analog scanner, especially fire dispatch channels since most of them are still simulcast on VHF for their pagers.
Most of these frequencies can be found in the RR Database, but here are some I listen to regularly:
154.385 Hennepin Co Fire
155.820 Hennepin Co Sheriff Tac 3
154.280 Anoka Co Fire
154.220 Ramsey Co West Fire
154.190 Ramsey Co East Fire
151.295 Dakota Co East Fire
154.785 Dakota Co West Fire
154.310 St Louis Park Fire
154.250 Golden Valley Fire
155.475 Statewide Law Enforcement (MINSEF)
154.295 Statewide Fire
155.340 North Memorial Air Care Ch. 1
155.400 Air Care Ch. 2
154.935 East Metro State Patrol
Also, Scott and Washington Counties have not yet switched to the digital ARMER system. They will probably be switching by the end of the year but for now you can still hear them on a regular scanner.