One suggestion: for one of those cables at least you may be able to find a standard cable at the auto parts store.. These starter cables are normally 4GA, and factory crimped rather well
I do not have the ability to crimp cable larger than 10ga but I can tell you this, A good proper crimp.. Be it 10ga, 12ga, 18 ga or 0000ga One big cable) the wires wont wiggle.. Not at all
But it is not a "Cold weld" (That is a chemical glue) just a crimp
A welding supply house may be able to re-crimp em, that's where I got my last cable crimped... or a Solar Power Store. (The one it repalced, damage to the wire, NOT a bad crimp).