If you are planning on paralleling several devices and circuits to a common ground cable and then routing a single conductor to the battery ground terminal without soldering, I would suggest purchasing a terminal block and crimp terminal connectors, the eye-hole style would be best. Terminal blocks usually have multiple connection points, but these can be made common to each other with jumper wires.
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Some considerations. Make sure the common cable that is your "return path" to ground for all the circuits is of sufficient gauge to handle the amperage of all the circuits in sum, PLUS a bit of headroom. This is for multiple reasons. First, you do not want any added wire resistance that will cause overheating and potentially a fire. Secondly, long runs of ground wire will cause ground loops and can cause strange circuit behavior. Adequate wire gauge can minimize the opportunity for this.
Consider that your terminal block connections will be exposed to harsher conditions (possible saltwater?) and also vibration. A lock washer might be a good idea for each terminal...and a conservative bit of "Locktite" on the threads of the terminal screws may prevent a loose connection. Be careful, I'm not sure how conductive or insulative Locktite is but I use it conservatively with no problems. After connections are securely made, sealing your terminal block with silicon or in a protective box might not be a bad idea to prevent corrosion.
Also, it is not uncommon to fuse the ground wire that acts as your return path. Calculate the wire gauge and the parallel current of all your circuits under normal conditions. A good rule of thumb is to fuse for 10% above the expected operating current with a slow blow fuse. This will protect your ground cable from overheating and overloading.