These 7s built like aircraft and aluminum boats. Actually, they're built worse than planes and boats. There is very little built-in corrosion abatement. They are susceptible to electrolysys and corrosion . For long term care, and to ensure you're not chasing down electrical problems in a few years, understand why battery isolation, when not using the car, is a good practice.
https://www.twi-global.com/technical-knowledge/faqs/faq-what-is-galvanic-corrosion-and-how-can-it-be-avoided