Hey!
Isn't the BL-1 cable is for interconnector use?
And which banana are we talking about here?
If they are crimp type than you could striped out the wire use hobby knife to scrape the conductors a bit to clean it off.... scrape around the inside of the banana plug too. Than put the wire in and crimp it very hard. And solder it to fill in the void in side and to seal the connection off.

Well, that is what I do with my speaker cable but I use spades. Hope this help

Take care,
Buddy

PS
Why this post is here anyway? This sound like something that belong in "The Lab"

You might get more respond there.