Dynamic AUX

Made for a dual battery system.

VARTA® Auxiliary batteries provide electrical components with seamless functionality. This enables an increase in the length of the start-stop moment and supports comfort functions during engine start. Modern cars consume a significant amount of electricity. Therefore, these cars with a combustion engine often come with two batteries: a regular 12 volt starter battery and an auxiliary battery.

Trust a battery expert near you!

As cars become more and more complex so do their battery exchanges. That's why we do not recommend you to exchange your battery by yourself unless you are a battery professional. Instead, reach out to one of our trusted VARTA® Partner workshops instead

Got a question?

  • Since the turn of the millennium, start-stop technology has been introduced in more and more vehicle segments and models to comply with increasingly stringent emission regulations. Nowadays, there are hardly any new vehicles that are delivered without a start-stop function. In other words, the newer the vehicle, the more likely it is to feature automated engine shutoff.

    If the car is equipped with a Battery Management Sensor, it has a Start-Stop system or at least a Smart-Charging System that requires advanced battery technology such as AGM or EFB

    Go to VARTA® Battery Finder

  • For a car with a start-stop system, the recommended battery types are Absorbent Glass Mat (AGM) or an Enhanced Flooded Battery (EFB) battery.

    If an AGM battery is already installed in the vehicle, it must always be replaced with another AGM battery since the vehicle's Energy Management could overstress a Flooded battery which leads to shortend battery lifetime.

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  • Although both AGM and EFB technologies are used for Start-Stop applications, there are some differences in the technologies' performance. While EFB is an improved flooded battery, AGM is a battery specifically designed for demanding applications and able to support any types of Start-Stop systems and even xEV.

    Downgrading from an AGM to an EFB is not recommended since the vehicle's Energy Management System is designed for a certain battery performance. Upgrading from EFB to AGM on the other hand, is always possible and advised when your customer faces recurring battery issues.

    Find more on AGM, EFB, xEV and more in our Knowledge section.

    Go to Knowledge