What Battery Does an Audi A4 Take?

An Audi A4 typically uses a 12‑volt AGM (Absorbent Glass Mat) or EFB (Enhanced Flooded Battery) with around 70–110 Ah capacity and 680–950 CCA, but the exact battery type, size, and specification depend on the model year, engine, and whether the car has start‑stop or mild‑hybrid technology. Owners should match the original specification and, on most modern A4s, have the new battery registered or coded to the vehicle.

Why the “Right” Battery Matters on an Audi A4

The Audi A4 has evolved from a relatively simple electrical system in the 1990s to an electronics-heavy, networked platform with start‑stop, energy recovery, advanced infotainment, and driver-assistance systems. As a result, choosing a random 12‑volt battery is no longer enough. The battery chemistry, size, cold‑cranking performance, and integration with the car’s energy management system all influence reliability, longevity, and even fuel consumption.

Key Battery Types Used in the Audi A4

Audi has used different battery technologies over the A4’s generations. Understanding the main types makes it easier to select a correct replacement that matches both the physical fit and the electrical demands of the car.

• AGM (Absorbent Glass Mat) battery – Sealed, spill‑resistant design that handles deep cycling well; common on A4s with start‑stop or higher electrical loads.
• EFB (Enhanced Flooded Battery) – An improved version of conventional flooded batteries; often used on some start‑stop equipped models as a cost‑effective alternative to AGM.
• Conventional flooded lead‑acid battery – Found mainly on older, pre–start‑stop A4s and some lower‑spec early B7/B8 models.
• Auxiliary batteries (12 V) – On some newer mild‑hybrid or high‑equipment variants, a small auxiliary battery can support specific systems alongside the main battery.

While all of these are 12‑volt lead‑acid–based systems, the internal construction and durability differ substantially, which is why replacing an AGM or EFB with a basic flooded unit is generally not recommended on a modern A4.

Battery Specifications by Audi A4 Generation

The A4 nameplate spans several generations, each with slightly different battery requirements. The broad trends are similar across global markets, though exact specs and part numbers can vary by engine, climate package, and equipment level.

B5 (1994–2001): Early A4 Models

The first-generation A4 (B5) has comparatively modest electrical demands. Most cars used a conventional flooded lead‑acid battery.

• Voltage: 12 V
• Capacity: typically 60–72 Ah
• Cold Cranking Amps (CCA): roughly 540–680 CCA (varies by engine and climate)
• Form factor: European case sizes such as DIN/H6 or similar, depending on market
• Chemistry: standard flooded lead‑acid (no start‑stop)

On these models, any quality battery that meets or exceeds the original capacity and CCA and fits the tray and clamp system is usually acceptable, and no electronic coding is required.

B6 (2001–2005) and B7 (2004–2008): Growing Electrical Loads

With the B6 and B7 generations, electrical complexity rose: more power‑hungry accessories, optional navigation, and stronger climate systems. Start‑stop technology was not yet mainstream, so conventional batteries were still used, though with higher outputs.

• Voltage: 12 V
• Capacity: around 70–80 Ah on most engines
• CCA: typically 640–800 CCA
• Form factor: H6 (Group 48) or H7 (Group 94R) equivalents in many markets
• Chemistry: flooded lead‑acid; AGM was sometimes fitted for high‑spec or cold‑climate versions

These models are more sensitive to voltage stability, but battery replacement is still relatively straightforward compared with later generations, and coding is usually not required outside of certain high-spec variants.

B8 (2008–2016): Introduction of Start‑Stop and AGM

The B8 generation is where battery choice becomes more critical. Many A4s in this era, particularly diesels and models with efficiency packages, were fitted with start‑stop and recuperation systems, pushing Audi to use AGM or EFB batteries to cope with frequent cycling.

• Voltage: 12 V
• Common capacities: 70–95 Ah, with higher capacities on diesels and heavily optioned cars
• CCA range: roughly 680–900 CCA
• Chemistry options:
  

  • AGM for most start‑stop equipped models
  • EFB or high‑quality flooded battery on non–start‑stop variants

• Form factor: H7/94R or similar long-case European sizes
• Battery management: many B8s use a Battery Energy Management (BEM) system that benefits from battery coding/registration

For B8 owners, matching the existing type (AGM vs EFB/flooded) is essential. Replacing an AGM start‑stop battery with a cheaper flooded unit can shorten battery life and cause charging problems or fault codes.

B9 (2016–Present): Start‑Stop as Standard and Mild‑Hybrid Variants

The current B9 generation, including the facelifted models, almost universally uses start‑stop, with many markets offering 12‑volt mild‑hybrid (MHEV) systems. This further increases the importance of a correctly specified AGM or suitable EFB battery, as well as proper integration with the car’s energy management electronics.

• Voltage: 12 V main battery, plus 12 V or 48 V auxiliary system in some mild‑hybrid versions
• Main battery capacity: commonly 70–110 Ah depending on engine (1.4/2.0 TFSI, 2.0/3.0 TDI, etc.) and equipment
• CCA: approx. 720–950 CCA
• Chemistry:
  

  • AGM as the default on most start‑stop and MHEV cars
  • EFB on some lower‑demand, non‑MHEV variants in select markets

• Battery management: requires battery registration/coding via OBD (using VCDS, ODIS, or equivalent) when a battery is replaced
• Auxiliary battery: certain models include a secondary 12 V battery for specific circuits or a 48 V lithium‑ion pack for MHEV; these have distinct specifications and replacement procedures

On B9 cars, installing the correct AGM or EFB battery and then telling the car’s control module about the new battery is crucial for accurate charging and to avoid premature wear or error messages.

How to Identify the Correct Battery for Your Specific A4

Because trim levels, climates, and market options can shift specifications, the most precise way to know what battery your A4 needs is to use the car’s documentation and physical labels rather than relying solely on generic online fitment tools.

• Check the existing battery label: It usually lists capacity (Ah), CCA, voltage, chemistry (AGM/EFB), and manufacturer part code.
• Consult the owner’s manual: Audi often specifies recommended battery specs or at least required capacities and types by engine.
• Use the VIN at a dealer or OEM parts database: With your VIN, a dealer or authorized parts catalog can pull the exact factory part number and specification.
• Note start‑stop and hybrid features: If your A4 has automatic engine stop at traffic lights, energy recuperation, or is branded as “TFSI e” or “MHEV,” assume AGM or high‑spec EFB is required.
• Measure the battery tray and terminals: Confirm length, width, height, and whether your car uses standard top‑post terminals and what side the positive terminal is on.

Taking these steps before purchase minimizes the risk of buying an incompatible battery that either doesn’t fit physically, fails to meet electrical demands, or conflicts with the vehicle’s energy management software.

Typical Battery Sizes and Codes for Audi A4

Battery retailers and catalogs often list batteries by standardized size codes. Understanding these codes can make shopping for an A4 battery more straightforward, especially if you’re comparing brands.

• H6 / Group 48: Common on some earlier and mid‑range A4 models; medium capacity (roughly 60–75 Ah) with a compact footprint.
• H7 / Group 94R: Very common on B7, B8, and many B9 cars; larger capacity (often 80–95+ Ah) and higher CCA.
• DIN sizes: In many European catalogs, DIN dimension codes correspond broadly to H6/H7‑type lengths and heights.
• AGM designations: Vendors may add “AGM” or “Start‑Stop” to the part name; an H7 AGM battery from different brands will often share similar dimensions and specs.

Although these codes help, always cross‑check capacity, CCA, terminal layout, and chemistry to match your original Audi battery and your car’s electrical requirements precisely.

Battery Replacement and Coding on Modern A4s

On recent Audi A4 models, especially from late B8 onward, replacing the battery is not just a mechanical job. The car’s control unit tracks battery age and condition, so a new battery should be “introduced” to the system digitally.

• Physical replacement: Disconnect the old battery (negative first), secure the new battery firmly in the tray, and ensure clean, tight terminal connections.
• Battery registration/coding: Using tools like VCDS, ODIS, or specialist aftermarket scanners, input the new battery’s parameters (capacity, type, manufacturer, serial or part number).
• Why coding matters: The energy management system adjusts charging voltage and strategy based on perceived battery age; if not reset, it can over‑ or under‑charge a new battery.
• Symptoms of skipped coding: Premature battery wear, unexpected start‑stop behavior, warning lights, or energy management errors.

While a mechanically experienced owner can often handle the physical swap, many drivers choose a shop or dealer service specifically to ensure proper coding and avoid future electrical issues.

Cost and Brand Considerations

Battery prices for an Audi A4 vary widely depending on type, brand, and whether coding is included in installation.

• Price range:
  

  • Standard flooded batteries for older A4s: typically lower cost.
  • AGM/EFB batteries for newer start‑stop models: significantly more expensive.

• OEM vs aftermarket:
  

  • OEM (Audi‑branded, often made by Varta, Banner, Exide, etc.) guarantees correct spec but at a premium.
  • Reputable aftermarket brands can match OEM specs at reduced cost if the correct type and rating are chosen.

• Installation services: Some battery retailers and workshops include testing, installation, and coding, which can be cost‑effective compared with dealer labor.
• Warranty: Higher‑quality AGM/EFB units often come with extended warranties; ensure the warranty remains valid when installed on start‑stop vehicles.

Balancing cost with specification and warranty protection is key: for a modern A4, saving money by downgrading to a basic battery can lead to more expensive issues later.

Maintenance and Lifespan Expectations

Although modern AGM and EFB batteries are largely maintenance‑free, their lifespan in an Audi A4 still depends heavily on driving patterns and system health.

• Lifespan: Commonly 4–7 years for high‑quality AGM/EFB in mixed use, shorter with predominantly short trips.
• Driving pattern impact: Frequent short urban trips with heavy start‑stop use stress the battery more than long highway journeys.
• Charging system health: A weak alternator, faulty sensors, or parasitic drains can dramatically reduce battery life.
• Storage considerations: If the car is unused for long periods, periodic charging or a smart maintainer helps prevent deep discharge.

Routine checks—such as monitoring starting performance and watching for warning messages—can catch a deteriorating battery before it leaves you stranded.

Summary

An Audi A4 uses a 12‑volt lead‑acid battery—most commonly a high‑capacity AGM or EFB unit on modern, start‑stop–equipped models, and a conventional flooded battery on older generations. Exact requirements depend on generation, engine, equipment, and region, with typical capacities between about 60 and 110 Ah and CCA ratings from roughly 540 to 950. The safest approach is to match the original battery’s type, capacity, and size, verify specifications via the existing battery label, owner’s manual, or VIN‑based parts lookup, and, on newer B8 and B9 cars, ensure the replacement battery is properly registered or coded to the vehicle. Doing so preserves reliable starting, protects the car’s electronics, and maximizes the new battery’s lifespan.

What size battery is in the Audi A4 2015?

Duralast Gold Group Size 94R H7 Battery H7-DLG.

What size battery is in the Audi A4 2017?

The battery size for a 2017 Audi A4 is typically BCI Group Size 94R (DIN Group Size H7). However, some models may use other sizes like H6 (Group 48), so it’s important to verify the specific battery group size for your vehicle before purchasing. A common battery will have approximately 800800800 cold cranking amps (CCA) and a 140140140-minute reserve capacity.
 

• Primary size: BCI Group Size 94R, or DIN Group Size H7. 
• Alternative size: Some models may use H6 (Group 48). 
• Performance: Common specifications include around 800800800 CCA and 140140140 minutes of reserve capacity. 
• Verification: Always check your vehicle’s owner’s manual or physically inspect your current battery to confirm the correct size and specifications for your specific model and trim. 

How much is the Audi A4 battery?

between $150 and $300
Typical Audi A4 car battery costs range between $150 and $300, but you need one that’s going to fit your exact year.

What battery does the Audi A4 use?

Value Battery – Battery: H6 Group Size, 615 CCA, 765 CA, 95 Minute Reserve Capacity (Part No. 48H6-V)