Varta AUX9 Dynamic AUX · Car battery 9Ah 130A

Varta AUX9 Dynamic AUX (formerly Silver Dynamic Aux) 9Ah 130A 12V Car Battery

The Varta AUX9 car battery is the 12 V, 9 Ah and 130 A cold cranking (EN) model from Varta's Dynamic AUX (formerly Silver Dynamic Aux) range, designed to work as an auxiliary battery in cars with advanced Start-Stop and a great deal of electronics. Its 151 × 87 × 106 mm dimensions and positive terminal on the left make it the exact replacement for the 9 Ah battery fitted as standard in many cars.

• Specific replacement for the backup battery fitted to the car at the factory.
• Supports the advanced Start-Stop system without voltage drops.
• AGM technology: maintenance-free and resistant to cycling.
• Auxiliary battery: it powers the vehicle's comfort and safety electronics.

Vehicles compatible with the Varta AUX9 battery

The Varta AUX9 is compatible with more than 18 vehicles: it is fitted as standard or as a replacement by brands such as Volvo and Mercedes-Benz. It is a benchmark option when you need a battery for Volvo, Mercedes-Benz or other models that use this same format. Not sure whether it is the right one for your car? Check in seconds by entering your registration number in our finder.

Format and fitting of the Varta AUX9

The Varta AUX9 is made in the 151 × 87 × 106 mm format and weighs 2,67 kg. The positive terminal on the left determines which side the cables end up on: it is the detail that causes the most purchasing mistakes, so it is worth checking before ordering. It uses a B00 hold-down and a Y4 terminal, the system that secures it to the vehicle's battery tray. Before replacing it, measure the space your current battery occupies: if it matches on all three dimensions and on the terminal positions, the swap is direct and needs no adapters.

The Varta AUX9 and the Dynamic AUX range

The Dynamic AUX range brings together Varta's auxiliary batteries: these are not the main starter battery but the one that powers secondary functions (advanced Start-Stop, safety and comfort systems) in premium cars.

It is installed alongside the main battery and prevents voltage drops in the auxiliary electronics. It is worth establishing clearly whether your car needs this backup battery in addition to the starter one.

This series uses lead-acid technology with plates optimised for a good balance between cranking power and service life. It is the natural substitute when your car does not have Start-Stop and came with a standard battery as original equipment: the same philosophy, without paying over the odds for a chemistry you do not need. This battery used to belong to Varta's Dynamic AUX range; following the brand's commercial renaming (2025), it forms part of the new Dynamic AUX series.

Why choose a Varta battery

Varta is an original equipment (OEM) supplier to a good share of Europe's car manufacturers: many cars leave the factory with a Varta fitted. Buying a replacement means, in most cases, refitting the original battery with the same quality and the brand's official warranty.

Varta combines more than a century of experience with Clarios's industrial production: it is the battery many manufacturers choose as standard and one of the most recommended by workshops. Like every lead-acid battery, it is 100% recyclable.

Varta is Europe's leading manufacturer of starter batteries: its production volume and quality controls guarantee consistent reliability batch after batch, something own-brand labels cannot always assure.

Manufacturer's warranty

The Varta AUX9 battery comes with the official manufacturer warranty.

Care and maintenance

To get the most out of it, keep the alternator in good order and avoid leaving lights or accessories on with the engine switched off. Repeated very short journeys are its main enemy: they stop the battery from recharging fully and shorten its life. If the car is going to stand unused for weeks, it is worth disconnecting a terminal or using a trickle charger so it does not discharge below the safe threshold. Checking that the terminals are clean and properly tightened also helps ensure reliable starting.