Lithium ion battery packs are ideal as a back-up in the event of a boat’s main electrical system failing. The Poweroak AC50S Powerbank is a 500W unit (roughly 40Ah at 12V) that’s compact and weighs little more then 6kg. What’s neat about this unit is the way it’s packaged, with multiple USB and 240V outlets, plus USB-C laptop power and an induction wireless charging facility. There’s also a useful LCD display that shows state of charge and the input charge rate – a 120W solar panel can be connected directly.
Price: £399. rallydesign.com