What Battery Does an Audi A4 Need?

An Audi A4 typically requires an AGM (Absorbent Glass Mat) 12V battery with specific cold-cranking amps (CCA) and capacity that depend on the model year, engine, and equipment; in most modern A4s, an AGM group-size battery correctly coded to the car’s battery management system is recommended to ensure reliability and avoid electrical issues. Choosing the right battery means matching physical size, terminal layout, capacity, and technology to Audi’s specifications for your particular vehicle.

Why the “Right” Battery Matters on an Audi A4

The Audi A4 is heavily dependent on electronics—from start-stop systems and infotainment to advanced safety and driver-assistance features. These systems make the car sensitive to battery type and specification. Using the wrong battery can lead to hard starts, fault codes, and even premature alternator failure, especially on newer models equipped with energy-management systems.

Common Battery Types Used in the Audi A4

The Audi A4 platform has evolved significantly since the 1990s, and the battery technology has evolved with it. The main distinction today is between conventional flooded lead-acid batteries and newer AGM batteries designed to handle higher electrical loads and frequent start cycles.

AGM vs. Conventional Flooded Batteries

Most recent Audi A4 models, especially those with start-stop systems, require or strongly recommend AGM batteries. Older models may still use conventional flooded batteries, but upgrading to AGM is often beneficial if compatible and correctly coded.

The following list outlines the key differences between AGM and conventional batteries as they relate to the Audi A4.

• AGM (Absorbent Glass Mat): Better suited for high electrical loads, start-stop systems, and frequent short trips; offers improved vibration resistance and lower self-discharge.
• Conventional flooded lead-acid: Generally cheaper but less robust for heavy electronic use and repeated deep discharges; more common on older A4 models without start-stop.
• Energy management compatibility: Audi’s battery management system (BMS) is usually calibrated for AGM on newer models; using a non-AGM battery can reduce battery life and system reliability.
• Climate performance: AGM batteries typically offer stronger cold-cranking performance and better recovery from deep discharge—useful in cold climates and urban stop-and-go driving.

Understanding these differences helps ensure that the battery you choose will cope with the A4’s electrical demands and interact properly with its charging and energy-management systems.

Typical Battery Specifications by Audi A4 Generation

Battery requirements vary by generation, engine type, and equipment level. The figures below are typical examples from major aftermarket catalogs and workshop data; always confirm by checking your existing battery label, owner’s manual, and VIN-based parts lookup.

Audi A4 B6/B7 (Approx. 2001–2008)

These models generally use conventional flooded lead-acid batteries, though AGM can sometimes be used as an upgrade if correctly matched.

The following list gives common specifications seen on B6/B7 A4 models.

• Voltage: 12 V
• Typical capacity: Approx. 70–80 Ah
• Cold Cranking Amps (CCA): Roughly 640–760 A (varies by engine and climate package)
• Battery technology: Conventional lead-acid (AGM optional upgrade)
• Location: Engine bay (in most markets)

For these generations, exact specs mainly depend on engine displacement (1.8T, 2.0, 3.0, 3.2, diesels) and options like heated seats or high-end audio, but coding through diagnostics is usually not mandatory on these older platforms.

Audi A4 B8 (Approx. 2008–2016)

The B8 generation, including many start-stop models, shifted toward AGM batteries and more sophisticated energy management. Battery registration/coding becomes more important here.

The following list summarizes typical B8 A4 battery characteristics.

• Voltage: 12 V
• Typical capacity: Approx. 70–95 Ah (higher for diesels and heavily optioned cars)
• CCA: Typically 680–850 A
• Battery type: AGM strongly recommended, especially for models with start-stop
• Location: Usually in the trunk (right side under trim, depending on body style/market)
• Battery management: Many models require battery coding/registration when replaced

As electrical loads increased with the B8, installers increasingly need to match not only the physical size but also the battery technology and capacity to the factory specification.

Audi A4 B9 (Approx. 2016–present)

The current B9 generation (including facelift models) is built around AGM technology and smart charging, particularly in vehicles with mild-hybrid systems and advanced driver assistance.

The following list explains what is generally expected for B9 A4 batteries.

• Voltage: 12 V (plus an additional 48 V system on some mild-hybrid variants, which uses a separate battery)
• Capacity: Around 70–95 Ah for the main 12 V battery, depending on engine (TFSI, TDI), quattro, and equipment
• CCA: Frequently 700–850 A or higher
• Battery type: AGM is the standard specification
• Location: Commonly in the trunk, behind the side trim
• Programming: Battery replacement should be followed by BMS coding/registration using compatible diagnostic tools (e.g., VCDS, ODIS, dealer systems)

On B9 and newer A4s, using the correct AGM battery and registering its details in the car’s control module is crucial to maintain proper charging behavior, battery longevity, and system stability.

Battery Group Sizes and Fitment

In many regions, batteries are categorized by “group size” (North American BCI groups) or Euro designations (e.g., H6, H7, H8 or L2, L3, L4 types). For the Audi A4, several group sizes recur frequently, depending on space and required capacity.

The following list covers the most commonly used battery sizes for Audi A4 models in Europe and North America.

• Group H6 / 48 (approx. 70 Ah): Often seen on smaller-engine A4s or cars with lighter option loads.
• Group H7 / 94R (approx. 80–85 Ah): A popular size for many mid-spec A4s; balances capacity, size, and cost.
• Group H8 / 49 (approx. 90–95 Ah): Common on higher-spec vehicles, larger engines, diesels, and cold-climate packages.
• Terminal layout: Most A4s use “right positive” (R) arrangement; choosing the wrong layout can make cables difficult or impossible to connect safely.
• Height and length constraints: The battery must fit under covers and into the battery tray without contacting bodywork or trim.

While there is some flexibility between sizes like H6, H7, and H8, you should match the original configuration unless a professional confirms that the mounting, venting, and electrical requirements are still satisfied.

How to Identify the Correct Battery for Your Specific A4

Because year, engine, and equipment vary widely, the most reliable way to determine the correct battery is to decode your car’s individual specification rather than guessing from general model-year ranges.

The following list outlines practical steps to confirm the right battery for your Audi A4.

• Check the existing battery label: Look for Ah rating, CCA value, technology (AGM/EFB/flooded), and any part numbers or QR codes.
• Use your VIN: Dealer parts departments, reputable independent garages, and some online catalogs can retrieve the exact OEM battery spec via the VIN.
• Consult the owner’s manual: Many manuals list recommended capacity and type, plus notes for vehicles with start-stop or heavy-duty equipment.
• Look for start-stop and mild-hybrid features: If your A4 has start-stop, advanced energy recuperation, or a 48 V mild-hybrid system, you almost certainly need an AGM (and possibly an additional 48 V battery, handled separately).
• Inspect the mounting and venting setup: Trunk-mounted batteries require proper vent connections; side-mounted vent ports must align with the battery design.

By combining the information from your existing battery, VIN lookup, and manual, you can confidently select a replacement that meets Audi’s technical requirements and physically fits the vehicle.

Battery Coding and Registration in Modern Audi A4s

On most recent A4 models, simply swapping the battery without telling the car’s control unit is a mistake. The Battery Management System tracks battery age, internal resistance, and charge history; replacing the battery without updating these values can result in undercharging, overcharging, or warning lights.

The following list explains the essentials of battery coding and why it matters.

• What coding does: Informs the control module that a new battery has been installed, with specific type, capacity, and manufacturer data.
• How it’s done: Via diagnostic tools (dealer systems, VCDS, or similarly capable OBD tools) that access the energy management module and input new battery information.
• Consequences of skipping coding: Possible reduced battery lifespan, improper charge levels, sporadic electrical issues, and stored fault codes.
• When it’s required: Typically essential on B8 and B9 models and strongly advisable on any A4 with advanced energy management or start-stop.

While physically changing the battery is within reach of a competent DIY owner, many drivers choose professional installation to ensure that coding and testing are done correctly.

Signs Your Audi A4 Battery Needs Replacing

Knowing when to replace the battery helps prevent inconvenient no-start situations and protects delicate electronics from low-voltage events.

The following list details typical warning signs that the battery in an Audi A4 is reaching the end of its life.

• Slow cranking or hesitant starting: The engine turns over sluggishly, especially after the car has been parked overnight or in cold weather.
• Frequent start-stop deactivation: The start-stop system disables itself more often than normal, indicating the battery can’t sustain repeated starts.
• Electrical glitches: Flickering lights, erratic infotainment behavior, or intermittent warning lights linked to low system voltage.
• Age: OEM AGM batteries often last around 4–6 years under typical conditions; conventional batteries can fail sooner, especially in extreme climates.
• Diagnostic test results: A battery tester shows low state of health (SOH) or high internal resistance even if the car still starts.

When several of these symptoms appear together—particularly in a battery older than four years—it is usually more cost-effective and safer to replace the battery proactively.

Choosing Between OEM and Aftermarket Batteries

Owners can select genuine Audi-branded batteries or quality aftermarket units from major manufacturers, provided the specifications match Audi’s requirements.

The following list compares key considerations when deciding between OEM and aftermarket batteries for an Audi A4.

• OEM (genuine Audi/VAG) batteries: Guaranteed compatibility, often with correct coding information and venting design; usually more expensive but a safe default choice.
• Reputable aftermarket brands: Bosch, Varta, Exide, Yuasa, Interstate, and similar brands can match or exceed OEM performance when the correct spec is chosen.
• Warranty: Aftermarket options sometimes offer longer consumer warranties, though coverage varies by region and retailer.
• Correct labeling for coding: Many aftermarket AGM batteries supply the information needed for proper BMS coding, but it must be entered accurately.
• Price vs. total cost: A cheaper but incorrect or low-quality battery may lead to early failure and additional diagnostic costs; saving money upfront can be false economy.

For most Audi A4 owners, a high-quality AGM battery from a recognized manufacturer, installed and coded correctly, offers the best balance of cost, reliability, and longevity—regardless of whether it carries an Audi logo.

Summary

An Audi A4 generally requires a 12V AGM battery sized to the vehicle’s generation, engine, and equipment, with typical capacities between about 70 and 95 Ah and CCA ratings from roughly 680 to 850 A. Older B6/B7 models can often work with conventional lead-acid batteries, but B8 and especially B9 A4s are engineered around AGM technology and energy-management systems that expect specific battery characteristics. The safest approach is to match the original battery’s type, size, and capacity, verify details via VIN or the owner’s manual, and ensure that any replacement—particularly on newer models—is properly coded or registered in the car’s Battery Management System. Doing so maximizes starting reliability, protects sensitive electronics, and extends the life of both the battery and the charging system.

What battery do I need for my Audi?

Your owner’s manual should tell you what Audi battery you need – or you can check it instantly by using our battery search tool at the top of this page. Our battery test technicians can also advise you. Whatever the answer, we’re likely to have you covered.

Do Audis need a special battery?

Getting the right battery
Most batteries found in Audis today are referred to as value-regulated lead-acid batteries, or a VRLA. These are commonly known as rechargeable sealed batteries. These batteries are designed to adjust the voltage depending on what is needed of them.

What battery does the Audi A4 use?

An Audi A4 typically uses an Absorbed Glass Mat (AGM) battery, which is a type of lead-acid battery, most commonly in BCI Group Size 48 (H6) or Group Size 94R (H7), depending on the specific model year and trim. For the most accurate fit, check your vehicle’s specific requirements, as some models may use a different size, and the vehicle’s computer system may need to be reset after installation.
 
Common battery types and sizes

• AGM (Absorbed Glass Mat): This is the most common type used in modern Audi A4s. 
• BCI Group Size 48 (H6): A frequent option for many A4 models. 
• BCI Group Size 94R (H7): Another common battery size for the A4, often found in different years and trims. 

Important considerations

• Verify your specific model: Always confirm the correct battery size for your specific year, trim, and engine by checking the owner’s manual or a vehicle fitment tool. 
• Computer reset: After replacing the battery, the vehicle’s computer system may need to be reset by a service specialist. 
• Other sizes: Some model years or configurations might use other battery sizes, such as the Group Size 49 (H8) or Group Size 47 (H5). 

How much is a battery for an Audi A4?

Your Audi A4 will be happy to know that the search for the right Batteries you’ve been looking for is over! Advance Auto Parts has 18 different Batteries for your vehicle, ready for shipping or in-store pick up. The best part is, our Audi A4 Batteries start from as little as $89.99.