I had some time this weekend and made up some cables to connect my second battery to my battery bank. Cables are 1 AWG and used a 1/0  gauge batter terminal connector. Clamped the connector in a vice. Heat it with a blow torch and filled the connector with solder. Once filled I push the cable into the solder. Works pretty bell with the vice take much of the heat away after the torch was removed.

While one end cooled I worked the other cable until complete. Once both cables cooled down. I used   shrink wrapped and marked them with colored tape.