Get the PE ends, glue (with CA, of course) them onto .010" styrene sheet and carefully trim. You can use small drill bits, like a miniature round file, to clean up the open end.The styrene sheet will give it added thickness and impart a more realistic 3 dimensional appearance. Other than this, you're out o'luck.
Before you say, "Gee, that's a lot of work for something that small", I primarily build 1/35 armor and I've scratchbuilt things much smaller than 1/24-1/25 battery cable ends, using styrene, PE frets and actually carving items out of round, square and flat styrene stock.. Just take your time and you'll be surprised at the results.