Marine DNV Battery Pack

https://www.ecopowerbattery.com/products/marine-battery-pack/

Marine DNV battery packs are special battery packs designed for use in boats and other marine vehicles. They are composed of multiple cells connected together, usually in either a series or parallel configuration. Marine DNV battery packs are designed to be water-resistant and can operate in extreme temperatures. They are also designed to provide a long life, even when exposed to the harsh conditions of the open sea.