Battery Isolators prevents auxiliary items such as fridges from drawing too much power from your vehicle’s starting battery and draws power only from the auxiliary battery when the vehicle is not running. It also helps manage charging by first allowing charge to flow only through to the main battery| before connecting charge to the auxiliary battery once the main battery reaches a pre-determined charge level.

In a standard dual battery setup| when your vehicle is turned off| your fridge will draw power from both the starting battery and the auxiliary battery. If your fridge is running all night| it could potentially drain your vehicle’s starting battery| preventing you from starting the vehicle the next day. Thunder’s Battery Isolator detects when the starting battery drops below 12.8 volts| directing charge only from the auxiliary battery| preventing the main battery from draining.