What's the name of this electrical connector?
That's just two ring crimp terminals connected by a bolt.
It's a terrible job. The left one is badly frayed and the right one is showing signs of burning. There is no easy way to insulate the connection properly.

Figure 1. They are designed to be terminated on securely mounted studs - either direct to a chassis or onto a stud mounted on an insulated base. Image source: Interfacebus.