CAN THE CFX3 KEEP FOOD COLD IF IT ISN’T CONNECTED TO A POWER SOURCE OR MY BATTERY DIES?

Yes. In our lab testing we found that the items in the cooler (33 cl soda cans) warmed up at roughly 1.8 degree C per hour.  For this test the cooler internal temperature was 3.3 C and the ambient temperature was 21 C.  There were 24 cans in a CFX3 55.