For emergency battery power on the cheap just get a few cheap cordless drills. Harbor Freight had some nice 18v ones recently for just 16 dollars.
The battery pack typically has 12 to 16 Nicad AA cells in it. The motor inside also works as a generator. Open the battery pack and remove the AA cells. Get a short piece of something like small rebar and put two bends in it using a bench vise so as to fashion a crank handle to fit in the drill chuck. Use a short piece of small PVC pipe to make a slip handle for the crank. Open the drill and connect the motor leads to wires so you can connect this to the batteries you wish to charge.(get the polarity right!) Secure the drill to a workbench... plumbers strap and drywall nails works well. Crank away! No regulation but it will charge batteries... Add a cheap 7805 regulator and you can safely charge something like a cellphone. A solar panel is a much easier way to charge batteries but in a pinch a hand crank generator can be useful.
What do yopu think you’re going to run with a little piece of junk like that?
An automobile alternator will put out about a thousand times as much with the same cranking effort.