What Kind of Battery a 2007 BMW 328i Takes
A 2007 BMW 328i typically uses a Group 94R (also called H7 or L4) AGM or flooded lead-acid battery, around 80–90 Ah and about 720–800 CCA, mounted in the trunk and usually requiring battery registration after replacement. This choice can vary slightly by market and options, but 94R is the standard fitment for most E90-generation 328i sedans and coupes.
Contents
Understanding the 2007 BMW 328i Battery Specification
The 2007 BMW 328i is part of the E90/E92 3 Series generation, which uses a modern, power‑hungry electrical system controlled by the car’s computer. Because of this, BMW specifies a particular physical size, terminal layout, and capacity, and in many trims recommends an AGM (Absorbent Glass Mat) battery for durability and electrical stability.
Battery Group Size: The Core Specification
The most important identifier for the battery is the group size. This determines whether the battery will physically fit in the tray, accept the hold‑down bracket, and allow the cables to reach the terminals correctly.
- BCI Group Size: 94R (also cross-referenced as H7 or L4 in European/EN standards)
- Polarity/Layout: “R” indicates reversed terminals, matching BMW’s cable routing
- Location: Trunk (right rear side, under the trim panel)
- Approximate Dimensions: About 12.4 in (315 mm) length, 6.9 in (175 mm) width, 7.5 in (190 mm) height
- Vent Port: Side vent required, with a plastic hose routed outside the vehicle
The following list outlines the key fitment details for the 2007 BMW 328i battery group size and form factor.
Together, these characteristics mean that a properly specified 94R/H7/L4 battery will physically fit the 2007 BMW 328i, connect correctly and safely vent gas to the outside.
AGM vs. Flooded: Which Chemistry Is Correct?
BMW equipped many E90 3 Series models with either conventional flooded lead‑acid or AGM batteries depending on options, climate, and market. The 328i can accept either type as long as the vehicle coding and registration matches the installed chemistry.
- AGM (Absorbent Glass Mat):
- Better resistance to deep discharge and frequent starts
- More stable under high electrical loads (heated seats, iDrive, audio upgrades)
- Generally recommended if the car originally came with AGM or is used in extreme climates
- Flooded Lead-Acid (Conventional):
- Often less expensive than AGM
- Sufficient for milder climates and lightly equipped cars
- Still must match the correct size and have a vent port
- Matching Original Spec:
- If your 2007 328i was factory‑equipped with AGM, replacing it with another AGM is best practice.
- If it had a conventional battery, you may keep the same type or upgrade to AGM with proper coding/registration.
The following list explains the differences and considerations between AGM and flooded batteries for this model.
The primary rule is that the car’s electronics must be informed of whichever chemistry you install so the charging strategy stays correct and does not shorten the new battery’s life.
Key Electrical Ratings: CCA and Ah for the 2007 BMW 328i
Beyond physical size and chemistry, capacity and cranking power ensure reliable starting and stable electrical performance. BMW’s original equipment batteries for the E90 328i fall in the mid‑to‑high range for a mid‑size sedan, reflecting the vehicle’s electrical demands.
Cold Cranking Amps (CCA)
Cold Cranking Amps measure how well a battery can start the engine in low temperatures. For the 2007 BMW 328i, staying close to the factory spec is recommended, especially in colder climates.
- Typical CCA Range: About 720–800 CCA for quality Group 94R replacements
- BMW OE/Dealer Batteries: Generally around 720–760 CCA, depending on brand and chemistry
- Cold Climate Considerations: Higher CCA (near 800) can be beneficial in regions with severe winters
The following list shows typical CCA specifications for replacement batteries in this model.
Staying within this CCA range ensures that the 328i’s inline‑six engine will crank reliably while maintaining compatibility with the vehicle’s alternator and charging system.
Amp-Hour (Ah) Capacity
Amp-hour capacity reflects how much power the battery can deliver over time, important for vehicles with complex electronics and for periods when the engine is off but accessories are powered.
- Common Ah Ratings: Approximately 80–90 Ah for OEM‑equivalent 94R batteries
- BMW Factory Range: Often labeled around 80 Ah or 90 Ah depending on the original configuration
- Aftermarket Choices: Many premium AGM 94R units sit around 80–95 Ah
- Impact of Larger Capacity: Slightly higher Ah is generally acceptable but must be properly registered and coded
The following list summarizes typical capacity ratings for a 2007 BMW 328i battery.
Matching or slightly exceeding the original Ah rating gives a margin of safety for the 328i’s comfort and convenience electronics without overloading the charging system, provided the car’s software is updated accordingly.
Registration and Coding: Why It Matters on a 2007 BMW 328i
One critical difference between the 2007 BMW 328i and older cars is that it uses an Intelligent Battery Sensor (IBS) and a managed charging strategy. When you change the battery, the car must “learn” about the new unit to avoid over‑ or under‑charging.
What Is Battery Registration?
Battery registration tells the car’s control module that a new battery has been installed, and it resets the charging and battery aging data. Skipping this step can shorten the life of even a high‑quality replacement battery.
- Resets Battery Aging Data: The system stops assuming the battery is old and adjusts charging accordingly.
- Corrects Charging Profile: Ensures voltage and current levels are appropriate for a new battery.
- Prevents Overcharging: Especially critical for AGM batteries, which are more sensitive to charging abuse.
- Required After Changes: Needed any time you replace the battery, change its capacity (Ah), or switch between AGM and flooded.
The points below explain what registration does in practical terms.
Battery registration can be done at a BMW dealer, an independent European specialist, or by owners with suitable diagnostic tools and software designed for BMW’s E90 series.
What About Coding?
While registration confirms that the battery is new, coding ensures that the car is set for the correct battery type and capacity. Not every replacement requires coding, but changes in spec usually do.
- When the Chemistry Changes: Switching from flooded to AGM, or vice versa, should be coded so the charging strategy matches.
- When Capacity Changes: If you move from, for example, 80 Ah to 90 Ah, the car should be coded to the new capacity class.
- Existing Specification Kept: If you install an identical type and capacity, in many cases only registration (not additional coding) is needed.
- Tools Required: BMW-specific diagnostic tools (ISTA, or reputable aftermarket BMW scan tools) are typically necessary.
The following list details when coding is typically needed and what it adjusts.
Correct coding and registration help your new 94R battery last several years, maintain proper voltage, and avoid electrical gremlins in the 2007 BMW 328i’s sensitive electronics.
How to Choose a Replacement Battery for a 2007 BMW 328i
With size, chemistry, and the need for registration in mind, choosing a replacement battery becomes a matter of brand, quality, and usage profile. Many major battery manufacturers offer direct‑fit units for the E90 328i.
Checklist Before You Buy
Drivers often face an array of part numbers and marketing claims. A simple checklist helps narrow the options to those that truly fit the car and its requirements.
- Group Size: Confirm 94R / H7 / L4 is specified for your 2007 328i.
- Chemistry: Match what the car currently has (AGM or flooded) unless you plan to have coding updated.
- Capacity and CCA: Aim for approximately 80–90 Ah and 720–800 CCA.
- Vent Port: Ensure the battery has a vent hole that accepts the BMW vent tube.
- Brand and Warranty: Prefer reputable brands (often rebranded as BMW Original) with at least a 3‑year warranty.
- Installation Plan: Decide whether a shop will handle physical installation, registration, and coding.
The checklist below outlines the essential criteria for selecting the right battery.
By matching these criteria, you will end up with a battery that not only fits physically but also integrates cleanly with the 328i’s electrical and electronic systems.
Common Aftermarket Equivalents
While model numbers vary by region, several manufacturers sell direct replacements compatible with the 2007 BMW 328i. Exact part numbers change over time, but the pattern of group size and type remains the same.
- AGM 94R/H7: Premium AGM batteries marketed for European or “German car” applications.
- Flooded 94R/H7: High‑performance flooded lead‑acid units specifically labeled as 94R or H7.
- BMW OE Battery: Dealer-supplied 80–90 Ah battery, generally AGM in many markets, coded and registered on installation.
- European EN Codes: Sometimes referenced as L4 80Ah or similar on European-labeled batteries.
The following list gives typical product lines and designations seen for this car in various markets.
Regardless of brand name, confirming that the unit is a 94R (H7/L4 equivalent) with correct ratings and venting is more important than the specific logo on the case.
Installation Notes and Owner Considerations
Replacing the battery in a 2007 BMW 328i is more involved than on simpler vehicles but remains manageable with preparation. The trunk location helps with weight distribution but requires careful handling of trim and the vent hose.
Basic Installation Steps and Precautions
Home mechanics who want to install the battery themselves should understand the basic order of operations and safety issues, even if they plan to have a shop handle the electronic registration afterward.
- Power Loss Planning: Note that you will lose radio presets and clock settings when disconnecting power.
- Correct Disconnect Order: Disconnect negative terminal first, then positive, to reduce short‑circuit risk.
- Secure Mounting: Ensure the battery is firmly clamped in the tray; loose batteries can damage wiring or IBS components.
- Vent Tube Connection: Attach the vent hose securely to the battery’s vent port to prevent gas buildup in the trunk.
- Reconnect in Reverse Order: Positive cable first, then negative, avoiding contact between tools and bodywork.
- Post-Install Registration: Schedule or perform battery registration (and coding if needed) as soon as possible.
The following list outlines key practical considerations during battery replacement.
Following these measures helps protect both the new battery and the sensitive network of control units that manage the 328i’s engine, transmission, and comfort systems.
Summary
A 2007 BMW 328i typically uses a Group 94R (H7/L4) trunk‑mounted battery, usually in the 80–90 Ah, 720–800 CCA range, and often specified as AGM, though some cars left the factory with conventional flooded units. The physical size, reversed terminal layout, and venting are essential for safe fitment. Equally important, the E90’s electrical system requires battery registration—and sometimes coding—to match the new battery’s type and capacity. Choosing a quality 94R battery and ensuring proper electronic setup will deliver reliable starts, stable voltage for the car’s electronics, and maximum service life from the replacement unit.
How much is a battery for a 2007 BMW?
How much to replace the battery in my BMW? Depending on power, size, and quality, prices for a replacement car battery range from about $45 to $250.
What type of battery is in a BMW 328i?
A BMW 328i uses either a lead-acid, AGM, or EFB battery, depending on the specific model year and its features like start-stop technology. The car requires a 12V battery, and common group sizes include H6, H7, H8, and 94R. It’s essential to check the size, type (AGM or flooded), and specifications (like CCA) of the battery currently in your vehicle before purchasing a replacement.
Battery types and sizes for a BMW 328i
- Lead-acid: A standard option for older models.
- AGM (Absorbed Glass Mat): Often used in vehicles with start-stop systems for better performance and longevity. Many BMWs, even those not originally equipped with an AGM, can be upgraded to one, which can offer up to twice the lifespan of a traditional battery.
- EFB (Enhanced Flooded Battery): Used in some Asian vehicles with start-stop technology and can be a good option for some BMWs.
Common group sizes
- H6 (Group 48): Frequently found in many 328i models.
- H7 (Group 94R): Used in many models, including some with start-stop systems.
- H8 (Group 49): Found in older 328i models.
Important considerations
- Match specifications: When replacing the battery, match the cold-cranking amps (CCA) and other specifications of the old battery, or choose a more powerful one with the correct group size.
- Check your vehicle: The exact battery type and size can vary significantly between model years, so always check the battery in your car or use a vehicle-specific fit guide before buying.
- Reset the computer: After replacing the battery in newer models, the vehicle’s computer system will need to be reset to properly register the new battery, often requiring professional service.
Does it matter what kind of battery you put in a BMW?
Some models of BMW will require different batteries, so make sure you check the specifications of your vehicle before purchasing a replacement. However, many of them are interchangeable as they are the same (or similar) dimensions, whilst also carrying the same voltage.
What battery goes in a 2007 BMW 328i?
Duralast Group Size 49 H8 Battery H8-DL.
