well i left my radio charging and went out for dinner then went to the mall. when i came back, my radio was melting

, no kidding literaly it was melting. i forgot to unplug the wall charger, but it was supposed to stop charging

. well i got the batteies out and tested the voltage and they were all above 1.2v. my question is can they still be used again?
here's the damage

some of the heatshrink came off of the AA batts