You can install a USB plug and plug the charging cord into it in your boat or get a 12 Volt lighter plug style with a USB. I installed a USB on the right of the front seat where the cord is not in my way while using it. I think you should try another new battery as I get well over 5 out of mine now but first replacement battery I bought (online) wouldn’t last but about 4. Ordered a new one and it lasts twice that long