Don’t get stranded  – Add a Battery! 
Adding a second battery to the electrical system prevents the unintended discharge of the engine start battery.

Blue Sea Systems' popular Add-A-Battery kit was primarily designed for boats with an alternator output of 120A or less.

 When installed, the Add-A-Battery isolates the start battery from the house loads which prevents the discharge of the start battery. The Add-A-Battery offers a simple way to control the charging and battery switching of two battery banks. The E-Series Dual Circuit Plus™ Battery Switch simplifies the switching while the SI-ACR automates charging between two batteries.

The ADD-A-BATTERY is as simple to operate as an ON-OFF switch, yet effectively manages the switching and charging of two batteries from a single charge source

The Add-A-Battery includes a Dual Circuit Plus™ Battery Switch and an Automatic Charging Relay. These components simplify switching and automate charging so that all you have to do is turn the battery switch ON when you arrive and OFF when you leave.

e-Series 5511e Dual Circuit Plus™ Battery Switch

• Simplifies switching
• Isolates engine and house circuits
• Combines batteries for emergency starting
• Tin-plated copper studs for maximum conductivity and corrosion resistance

SI-ACR Automatic Charging Relay 7610

• Automatically combines batteries during charging
• Isolates batteries during engine cranking and when not charging
• Shares the charge between two batteries more efficiently than a battery isolator
• Allows efficient dual battery charging without needing regulator adjustment or rewiring