As others have said, the ampacity of a wire is typically based on how hot the insulation can get. One thing to keep in mind is that when you discharge a battery at 50 C, by definition, the discharge time will be extremely short. Because of this transient nature, the wire can sustain quite a bit of overload. Also, the only place where I see such high discharge rates in in the world of radio control (RC), where silicon jacketed wire is used with a very high temperature insulation. So there is less chance of melting the insulation compared to automotive wire or household wire.

There is a good possibility that the battery ratings are exaggerated, also. But since I am not active in RC stuff, I am not sure. Maybe some batteries really can be discharged completely in 1 minute or so. I think I would need to see it to believe it.

I have personally tested a bunch of name brand Japanese and Korean 18650s and none of the ones I tested could be discharged that rapidly without overheating.

As others have said, the ampacity of a wire is typically based on how hot the insulation can get. One thing to keep in mind is that when you discharge a battery at 50 C, by definition, the discharge time will be extremely short. Because of this transient nature, the wire can sustain quite a bit of overload. Also, the only place where I see such high discharge rates in in the world of radio control (RC), where silicone jacketed wire is used with a very high temperature insulation. So there is less chance of melting the insulation compared to automotive wire or household wire.

There is a good possibility that the battery ratings are exaggerated, also. But since I am not active in RC stuff, I am not sure. Maybe some batteries really can be discharged completely in 1 minute or so. I think I would need to see it to believe it.

I have personally tested a bunch of name brand Japanese and Korean 18650s and none of the ones I tested could be discharged that rapidly without overheating.