Get one of the boat pumps that looks like a bicycle pump, and attach a hose that will reach outside from the lowest area of the basement (where water would gather in the event power fails and the sump pump doesn’t work).
I use a shop vacuum, but it requires electricity.
around $5000.00 would solve your problem forever:
8 - 6 volt 240 AH Batteries from Costco, $100 each
8-12 24 volt Solar Panels USED $100 each Craigs List
1 Magnum MS4024PAE 240 Volt 40 Amp Grid Tie Inverter, $2500
1 MPPT Solar Charge Controller $200 on Ebay
some wiring,connectors,boxes,... $300
the prices I listed are from a while back, with Brandon in charge probably add 25%, but not only will this run your pump whenever you need it, it will keep a Full Size fridge and a full size freezer and lights on FOREVER!!
This is my Well Setup and it has worked flawlessly for 10 years