What Size Battery Is in the 2010 Audi S4?

The 2010 Audi S4 typically uses a 12‑volt AGM (Absorbent Glass Mat) battery in Group Size H7 (also known as 94R), with a capacity around 80 amp‑hours (Ah) and a cold cranking amps (CCA) rating in the 700–800 CCA range, depending on brand and market. This size and specification are designed to support the vehicle’s high electrical demands and advanced electronics.

Understanding the Factory Battery Specification

The 2010 Audi S4 (B8 generation) is a performance sedan with a supercharged 3.0 TFSI V6 engine and a sophisticated electrical system, including control modules, electronic power steering, advanced infotainment, and, in many trims, additional comfort and driver-assistance features. To power all of this reliably, Audi equips the car with a relatively large, high-specification battery.

Typical OEM Battery Size and Specs

While exact original equipment (OE) part numbers vary by region and production date, most 2010 Audi S4 models were fitted with a battery equivalent to the following common aftermarket specification:

The list below outlines the core specifications most owners should look for when replacing the original battery in a 2010 Audi S4.

• Battery Group Size: H7 (DIN size; also commonly cross-referenced as 94R in North America)
• Type: 12V AGM (Absorbent Glass Mat) maintenance‑free
• Capacity (Ah): Typically around 80 Ah (some catalogs list 80–95 Ah ranges)
• Cold Cranking Amps (CCA): Commonly about 730–800 CCA, depending on brand
• Reserve Capacity (RC): Generally in the 130–160 minute range (varies by manufacturer)
• Polarity/Terminal Layout: Recessed top posts, “94R” reverse terminal layout (positive usually on the right when facing the front)
• Mounting: Standard European-style hold‑down compatible with Audi’s battery tray in the trunk

Together, these specifications help ensure that replacement batteries match the original unit’s physical fitment and electrical performance, minimizing starting issues and avoiding conflicts with the S4’s energy management system.

Why the 2010 S4 Uses an AGM Battery

Although the 2010 S4 is not as electronics-heavy as some newer models, it still uses a smart charging system and has significant parasitic loads from control modules, sensors, and comfort systems. AGM batteries are favored in this environment because they tolerate deep cycling better than conventional flooded lead‑acid batteries, offer more stable performance in cold weather, and are generally more resistant to vibration—all important in a performance sedan.

Fitment Details: Dimensions and Compatibility

Not all batteries that meet the electrical specs will physically fit the battery bay or work seamlessly with Audi’s hardware. Proper size, terminal orientation, and venting are critical.

Physical Dimensions of the H7 / 94R Battery

While dimensions can vary slightly by manufacturer, the H7 (94R) format is standardized enough that most quality brands will drop straight into the 2010 S4’s battery tray in the trunk.

The following list summarizes the approximate dimensions and fitment aspects of the H7/94R battery used in the 2010 Audi S4.

• Length: Around 12.4 in (315 mm)
• Width: Around 6.9 in (175 mm)
• Height: Around 7.5–7.6 in (190–192 mm)
• Form Factor: European DIN-style casing with recessed top posts
• Mounting Style: Bottom hold‑down lip compatible with Audi clamp bracket
• Vent Port: Side vent connection to hook up to Audi’s vent tube (important because the battery sits inside the vehicle)

These dimensions ensure a secure fit within the trunk-mounted battery compartment, maintain safe venting of gases, and allow the stock clamps and covers to be reinstalled correctly after replacement.

Regional Variations and Dealer Part Numbers

Depending on where the S4 was sold (North America, Europe, or other markets), Audi dealerships may list slightly different part numbers and Ah ratings, but they remain within the same general class: large DIN H7/94R AGM batteries around 80 Ah. Some cars delivered to colder climates may have been equipped with batteries that skew toward the higher end of the available CCA range for stronger cold-weather starting.

Choosing a Replacement Battery

As these vehicles age, most original batteries have long since been replaced. Owners looking for the correct size should focus first on fitment (H7/94R) and AGM design, then on quality and warranty.

Key Factors When Selecting a New Battery

The list below outlines what 2010 Audi S4 owners should consider when selecting a replacement battery to match or exceed the original unit’s performance.

• Correct Size: Ensure the battery is designated Group H7 or 94R to fit the tray and clamps.
• AGM Construction: Prefer AGM over standard flooded batteries for compatibility with the S4’s charging and electrical systems.
• Similar or Higher Ah Rating: Aim for around 80 Ah; modestly higher capacity is fine if it still physically fits.
• Adequate CCA: Target at least the mid‑700 CCA range to ensure reliable cold starts, especially in colder climates.
• Quality Brand: Choose reputable brands (e.g., Varta, Bosch, Exide, Interstate, OEM‑labeled units) for consistent performance and warranty support.
• Proper Venting: Make sure the battery has a vent port that can connect to the S4’s ventilation tube, since the battery is inside the car.
• Coding/Registration Capability: Ensure that either you or your shop can register or code the new battery in the car’s control module if required.

Paying attention to these factors reduces the risk of starting problems, premature battery wear, or charging-system issues, while helping the car’s electronics manage energy usage correctly.

Battery Coding and the S4’s Energy Management

Although the 2010 S4 is not as strict as some later Audi models, it does employ an energy management system that tracks battery health and usage. When a new battery is installed, especially if the capacity or type changes, technicians commonly use diagnostic software (such as VCDS or dealer tools) to “register” or code the new battery. This helps the car adapt its charging strategy and avoid over‑ or under-charging, which can significantly affect battery lifespan.

Practical Tips for Owners

Knowing the correct battery size is just one part of maintaining a 2010 Audi S4’s reliability. Proper installation and maintenance habits also matter, especially in a performance-oriented car with aging electronics.

Installation and Maintenance Considerations

The following list highlights practical steps and precautions for owners who are replacing or caring for the battery in a 2010 Audi S4.

• Confirm Size Before Purchase: Check your current battery’s label for H7/94R and compare dimensions if uncertain.
• Protect Vehicle Settings: Use a memory saver or be prepared to reset windows, clock, and some convenience settings after replacement.
• Secure the Battery Properly: Always reinstall and tighten the hold‑down bracket to prevent movement and vibration damage.
• Connect Vent Tube: Make sure the vent hose is attached to the new battery’s vent port to route gases safely outside the cabin.
• Inspect Cables and Terminals: Clean corrosion and check for damaged or loose cables, which can mimic battery problems.
• Test Charging System: After installing a new battery, have the alternator and charging voltage checked to ensure proper function.
• Consider Professional Coding: If changing battery type or capacity, have the new battery registered with the car’s control module.

These steps help the new battery deliver its full service life and reduce the risk of electrical gremlins, intermittent starting issues, or warning lights that can arise from poor connections or misconfigured energy management.

Summary

The 2010 Audi S4 is designed to use a relatively large, high-performance 12‑volt AGM battery, typically in Group Size H7 (94R), with around 80 Ah of capacity and roughly 700–800 CCA. This format fits the trunk-mounted battery compartment, matches the car’s electrical demands, and works with Audi’s energy management system. When replacing the battery, owners should select an H7/94R AGM unit from a reputable brand, ensure proper venting and secure installation, and, where possible, have the battery registered or coded so that the S4’s charging system can manage it correctly.