What type of battery is used in a Subaru Forester?

A Subaru Forester primarily relies on a 12-volt automotive battery. In North American gasoline models this is a traditional lead-acid battery, while European-market hybrids use a small lithium-ion battery as part of a mild-hybrid system.

How the 12-volt system works in the Forester

The 12-volt battery powers starting, lighting, and accessory electronics, and it supports modest electrical loads when the engine is off. The main propulsion for most Forester configurations comes from the internal combustion engine, with no large high-voltage battery in standard setups. Battery chemistry and capacity can vary by year and market.

North American gasoline Forester: 12-volt lead-acid battery

Across most U.S. and Canadian Forester trims with gasoline engines, Subaru specifies a conventional 12-volt lead-acid battery, typically of a flooded type. Replacement options often include standard flooded lead-acid batteries, though some dealers or retailers offer absorbed glass mat (AGM) batteries as an upgrade for enhanced durability and electrical stability. Always verify the correct group size and specifications in the owner's manual or with a Subaru dealer.

European and hybrid variations: e-Boxer and hybrid support

In European markets, certain Forester models are offered with the e-Boxer mild-hybrid system, which combines a traditional internal combustion engine with electric assist. This configuration uses a small lithium-ion battery to support the hybrid function, in addition to the standard 12-volt electrical system used for accessories. The presence of a separate high-voltage hybrid battery means the vehicle’s battery architecture differs from the purely conventional gasoline model.

Care and replacement tips

For any Forester, keep the battery terminals clean, monitor the charge, and replace with the manufacturer-recommended type and capacity. If working on a hybrid/e-Boxer model, rely on trained technicians for high-voltage system work to ensure safety and compliance with service procedures.

Summary: Most Subaru Forester models use a 12-volt lead-acid battery, with European hybrid variants employing a small lithium-ion battery for hybrid support alongside the regular 12V system. Always confirm the exact specification for your year and market in the owner's manual or with a Subaru service center.

Does Subaru use a special battery?

Batteries Plus is your Subaru battery headquarters. Whether you drive an SUV like the Subaru Forester, Outback, Ascent or Crosstrek, or have a car like the Subaru Legacy or Impreza, the battery you're looking for is here, either in-store or online. Does your Subaru need a special battery to run? Not at all.

Is a car battery AGM or Lithium?

A car battery can be either AGM or lithium, but most standard cars use either a traditional flooded lead-acid battery or an AGM battery. Lithium batteries are a more advanced, lighter, and longer-lasting option often found in high-performance vehicles, while AGM batteries are a more powerful type of lead-acid battery that is becoming increasingly common and is a great choice for vehicles with start-stop systems.
 
AGM (Absorbent Glass Mat) 

• What it is: A type of lead-acid battery where the acid is absorbed into fiberglass mats, making it spill-proof and maintenance-free. 
• Why it's used: Offers better performance, longer life, and greater vibration resistance than traditional flooded batteries. It's a common upgrade for vehicles with start-stop systems that require frequent cycling. 
• Pros: More durable than traditional batteries, better cold-cranking power, and can be used in various positions. 
• Cons: Heavier than lithium batteries and typically more expensive than flooded lead-acid batteries. 

Lithium

• What it is: An advanced, newer technology that uses lithium iron phosphate (LiFePO4cap L i cap F e cap P cap O sub 4𝐿𝑖𝐹𝑒𝑃𝑂4) chemistry in most automotive applications. 
• Why it's used: Provides superior performance, a much longer lifespan, and is significantly lighter than other battery types. They are ideal for high-performance vehicles and those with advanced energy management systems. 
• Pros: Significantly lighter, faster charging, much longer lifespan (up to 10 years or more), and maintains consistent power even under heavy loads. 
• Cons: The most expensive option upfront and can be affected by extremely cold temperatures, though some models have cold-weather features. They require a system that is specifically designed to handle their specific voltage and charging requirements, notes Reddit. 

What kind of battery does a Subaru Forester need?

A Subaru Forester needs a Group 35 battery, with newer models (2019+) requiring an AGM or EFB (Enhanced Flooded Battery) type due to features like start/stop technology. The specific requirements can vary by model year and trim, so it is best to confirm the exact battery specifications by checking the owner's manual or the label on the current battery. 
Key specifications

• Group Size: Group 35 is standard for most models, though some specific trims or years might use a different size like Group 24F. 
• Battery Type:
  • 2019 and newer: An AGM (Absorbed Glass Mat) or EFB battery is recommended, especially for models with start/stop technology. 
  • Older models: A traditional flooded battery may be sufficient, but a modern AGM battery will also work and may offer longer life. 
• Cold Cranking Amps (CCA): A minimum of 550 CCA is a good benchmark, with many recommended replacements having 650 CCA or higher. 

How to find the right battery

• Check your owner's manual: This is the most reliable source for your vehicle's specific requirements. 
• Look at the old battery: The label on the current battery will have its group size and other specifications. 
• Use an online fitment guide: Websites for auto parts stores will have a "find the right battery" tool where you can enter your vehicle's year, make, and model to see compatible options. 

How much does a new battery for a Subaru Forester cost?

A Subaru Forester battery replacement costs approximately $180 to $350, but can range from about $45 to $250 for the part alone, depending on the battery's quality, size, and power requirements. The total cost will vary based on where you get the battery (auto parts store, dealership, etc.) and whether you pay for installation or do it yourself. 
Factors influencing the cost

• Battery type and quality: Standard batteries are cheaper, while premium or AGM (Absorbed Glass Mat) batteries for cars with start-stop technology will be more expensive. 
• Labor costs: Professional installation adds to the total price. The cost of labor varies by shop and location. 
• Model and year: Older Forester models may have lower costs, while newer models could be higher. 
• Battery warranty: Some batteries come with longer warranties, which can affect the initial price. 

Where to get your battery replaced

• Dealership: Often uses manufacturer-recommended parts and may have higher labor rates, but offers specialized knowledge. 
• Auto parts store: Offers a wide selection of batteries at competitive prices and may provide free installation with the purchase of a new battery. 
• Independent mechanic: Can be a good option for finding a balance between price and quality.