In this post in the Van Life Q&A, a user asks:
New question – how do I hook up an alternator isolator? No space for another clamp?
You could get a [kit with the cable and terminals included](https://www.amazon.com/Dual-Battery-Isolator-KeyLine-Chargers/dp/B00WTAFR5W?tag=beachfront08-20) if you don’t want to get them crimped or do them yourself.
However, I like [this style isolator better](https://www.amazon.com/Cole-Hersee-48160-Battery-Isolator/dp/B001FQOGK8?tag=beachfront08-20) where the alternator output goes to one pole and each of the other poles go to the batteries. This way it truly isolates them vs the other which is more of a charging relay and basically connects the batteries in parallel for the purpose of charging because it requires bridging from the battery terminal itself.