When drivers consider upgrading from a traditional lead-acid battery to a lithium iron phosphate (LiFePO4) battery, one of the first questions they ask is: “How much does a car LiFePO4 battery weigh?” The weight of a battery plays an important role in overall vehicle performance, fuel efficiency, and ease of installation. In this article, we will break down the typical weight of car LiFePO4 batteries, compare them with lead-acid batteries, and explain why weight matters when choosing the right battery for your vehicle.

Average Weight of a Car LiFePO4 Battery

The weight of a LiFePO4 car battery depends on its capacity (measured in amp-hours, or Ah), size group (Group 24, Group 31, etc.), and whether it is designed for starting or deep-cycle use. On average:

• 12V 100Ah LiFePO4 car battery: weighs 22–30 pounds (10–14 kg)

• 12V 50Ah LiFePO4 car battery: weighs 12–15 pounds (5–7 kg)

• 12V 200Ah LiFePO4 car battery: weighs 45–60 pounds (20–27 kg)

By comparison, a 12V 100Ah lead-acid battery typically weighs 55–70 pounds (25–32 kg). This means a LiFePO4 battery of the same capacity weighs about 50% less than its lead-acid equivalent.

Why LiFePO4 Batteries Are Lighter

The reduced weight comes from differences in chemistry and design:

1. Higher Energy Density – LiFePO4 stores more energy per unit of weight compared to lead-acid.

2. No Heavy Lead Plates – Instead of thick lead grids, LiFePO4 uses lightweight lithium compounds and aluminum/copper conductors.

3. Compact and Efficient Design – LiFePO4 batteries are engineered with modern cells and integrated Battery Management Systems (BMS), reducing unnecessary bulk.

The result is a battery that is not only lighter but also longer-lasting and more efficient.

Benefits of a Lightweight Car Battery

Switching from lead-acid to LiFePO4 reduces the strain on your vehicle. Here’s how weight savings make a difference:

• Improved Fuel Efficiency – Shedding 20–40 pounds in battery weight can slightly reduce fuel consumption, especially for smaller cars.

• Better Handling – A lighter battery means less front-end weight, which can improve balance and steering response.

• Easier Installation – Carrying and installing a 25-pound LiFePO4 battery is far easier than lifting a 65-pound lead-acid battery.

• Reduced Wear and Tear – Less weight reduces stress on battery brackets and electrical systems.

For performance cars, boats, and RVs, reducing weight can translate to real-world efficiency gains.

Popular Car LiFePO4 Battery Weights by Size

Below are common LiFePO4 battery group sizes and their typical weights:

• Group 24 (12V 100Ah) – 22 to 28 lbs (10–13 kg)

• Group 31 (12V 100Ah or 120Ah) – 28 to 32 lbs (13–15 kg)

• Group 27 (12V 90Ah to 100Ah) – 24 to 30 lbs (11–14 kg)

• Small Starter LiFePO4 (20–40Ah) – 5 to 12 lbs (2–5 kg)

This is a significant reduction compared with equivalent lead-acid batteries in the same groups, which often weigh 50–75 lbs (23–34 kg).

How Weight Affects Performance

The weight of a LiFePO4 battery is not just about convenience—it also influences performance:

1. Starting Power – A lighter LiFePO4 battery still delivers high cranking amps, often outperforming heavier lead-acid units.

2. Longer Lifespan – Even though it’s lighter, a LiFePO4 battery lasts 3,000–5,000 cycles compared to 300–500 cycles of a lead-acid battery.

3. Energy-to-Weight Ratio – A 25-pound LiFePO4 can provide the same usable energy as a 65-pound lead-acid battery, making it far more efficient.

LiFePO4 Battery Brands and Their Weights

Here are examples from well-known manufacturers:

• Battle Born 12V 100Ah LiFePO4 – 31 lbs (14 kg)

• Renogy 12V 100Ah LiFePO4 – 26 lbs (12 kg)

• OKMO 12V 100Ah LiFePO4 – ~25 lbs (11.5 kg)

• Ampere Time 12V 100Ah LiFePO4 – 24 lbs (11 kg)

• Lithium Pros 12V 120Ah LiFePO4 – 32 lbs (15 kg)

While weights vary slightly depending on the brand’s casing and BMS design, they are all significantly lighter than comparable lead-acid models.

Things to Consider Beyond Weight

Although weight is important, it should not be the only factor when choosing a LiFePO4 battery. You should also check:

• Cold Cranking Amps (CCA) – If used as a starter battery.

• Battery Management System (BMS) – Protection from overcharge, over-discharge, short circuits, and temperature issues.

• Operating Temperature – LiFePO4 cannot be charged safely below 0°C unless it has a built-in heating feature.

• Cycle Life – How many charge/discharge cycles the battery supports.

Final Thoughts

So, how much does a car LiFePO4 battery weigh? Typically between 22 and 32 pounds for a 12V 100Ah model—less than half the weight of a traditional lead-acid battery of the same size. This weight reduction improves efficiency, handling, and ease of installation, making LiFePO4 batteries the superior choice for many modern drivers.

If you are considering replacing your lead-acid battery with a LiFePO4, you can expect a dramatic weight savings along with better performance, longer lifespan, and reduced maintenance. Whether for cars, RVs, or marine use, LiFePO4 delivers the perfect balance of power and lightweight design.