Curated picks
Battery Isolators
Run a second battery without draining your starter battery
A battery isolator lets you add a second (auxiliary) battery for accessories, camping, or a winch, while protecting your main starter battery from being drained. Voltage-sensitive relays charge the second battery when the engine runs and isolate it when off.
We feature dual battery isolators and VSR kits on Amazon. Match the amperage to your setup and look for clear wiring instructions or a complete kit.
Top picks
Popular battery isolators
What to look for
- Amperage rating for your load
- Voltage-sensitive relay type
- Complete kit with wiring
- Quality terminals and fuses
FAQ
What does a battery isolator do?
Do I need a special battery?
Is wiring hard?
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