8 Best 40 Volt Batteries for Lawn Mowers to Buy in 2025

A dying battery mid-mow is more than just frustrating—it stops your work in its tracks, breaks your rhythm, and often results in an unevenly cut lawn.

Many homeowners face ongoing issues when relying on a 40-volt battery for lawn mower systems, such as poor battery life, inconsistent performance, or difficulty finding compatible replacements.

The right 40V battery offers long-lasting performance, dependable output, and full compatibility with your existing tools.

We evaluated many models, focusing on amp-hour ratings, safety protections, and real-world user feedback to recommend only the most reliable choices for 2025.

Whether you have a small yard or a larger property, our top selections deliver consistent power and fast charging. Discover the best 40-volt battery for lawn mower needs and keep your yard looking sharp without interruption!

1. Cheerlark 7.5Ah 40V Battery: Best Overall

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If you are tired of mid-mow shutdowns and crave unmatched runtime, the Cheerlark 7.5Ah 40V battery is a game-changer.

Boasting a massive 300Wh capacity—the highest in this lineup—it delivers up to 50% longer runtime than standard 6.0Ah packs.

This makes it ideal for large lawns and power-hungry Ryobi tools. The premium lithium-ion cells ensure stable voltage output from full to empty, preventing performance weakening.

In real-world testing, especially with high-draw devices like mowers and blowers, the Cheerlark maintained strong performance under load with minimal voltage sag.

Positioned between budget clones and OEM pricing, it offers 25% more capacity than most third-party 6.0Ah options. It’s the clear choice for homeowners with large yards or frequent tool use who want serious endurance and maximum runtime.

Key Features

• 7.5Ah/7500mAh capacity (Highest in the lineup)
• 40 Volt with 300Wh capacity
• Compatible with Ryobi 40V models (e.g., OP40601/OP4040/OP4050)
• Built-in 4 LED Display for precise charge feedback
• CE Certified

Pros

• Unmatched runtime and 50% longer runtime than 6.0Ah packs
• Ideal for large lawns and demanding applications
• High energy density and stable voltage output
• Maintained strong performance even under load

Cons

• Heavier than stock batteries due to high-density cells
• Slightly slower recharge time
• Peak output may lag slightly behind genuine Ryobi high-output models during sustained heavy-duty use

2. Biswaye 6.0Ah 40V Battery: Best Budget Friendly

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The Biswaye 40V 6Ah battery delivers serious value without sacrificing performance. It is the go-to choice for budget-conscious users who still need reliable power.

With a 6.0Ah (6,000mAh) capacity, this battery doubles the runtime of standard 3.0Ah Ryobi batteries, providing enough energy for medium to large lawns on one charge.

It features high-quality lithium-ion cells for consistent power delivery and integrated circuit protection to guard against overcharging, overheating, and short circuits.

This protection is critical for long-term tool health. The Biswaye battery performed admirably during testing with a Ryobi 40V lawn mower and string trimmer, handling up to a 1/2 acre yard. It offers the most cost-effective entry point into high-capacity Ryobi power.

Key Features

• 40V and 6.0Ah capacity
• Lithium-Ion cells with integrated circuit protection
• Extensive Ryobi compatibility (e.g., OP4050A, OP4060A, OP4040, etc.)
• FCC, RoHS, and CE safety standards certified
• Onboard LED power indicator lets you check charge status at a glance

Pros

• Delivers serious value with affordable pricing
• Tool and charger compatible (fits OP401 and ZROP401 seamlessly)
• Doubles the runtime of standard 3.0Ah Ryobi batteries
• Handles standard mowing and trimming with ease

Cons

• Average thermal performance
• Not recommended for continuous heavy loads
• Does not match the peak output or thermal management of OEM high-output batteries

3. Compatible with Ryobi 6.0Ah Battery: Best for High-Output Use

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This 40V 6.0Ah high-output battery is engineered for demanding outdoor tasks and challenging jobs where most clones might fail.

It features 6-layer circuit protection and industrial-grade thermal resilience, allowing it to operate reliably in extreme temperatures, specifically from -4°F to 122°F. It provides 33% longer runtime than 4.0Ah models.

This unit is built to deliver rugged dependability and sustained power delivery, making it ideal for users pushing their Ryobi tools to the limit.

It maintains performance thanks to advanced thermal regulation and its high-output cell configuration, minimizing voltage drop under load. It is one of the few clones explicitly rated for demanding tools like snow blowers and impact tools.

Key Features

• Ryobi 40V 6.0Ah High-Output Battery compatibility
• Operates across a wide temperature range: -4°F to 122°F
• Rated for 500+ charge cycles
• Features 6-layer circuit protection
• 4-LED charge indicator provides clear, accurate feedback

Pros

• High-output design delivers sustained power
• Excellent thermal resilience for all-weather operation
• Minimal voltage drop under heavy load
• Ideal for high-drain applications like chainsaws and snow blowers

Cons

• Slightly bulkier design than OEM
• Less refined finish
• The plastic housing feels less premium than genuine Ryobi packs

4. MAFACBAC 6.0Ah Greenworks Battery: Best Budget for GreenWorks

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For Greenworks users who seek maximum value without sacrificing compatibility, the MAFACBAC 6.0Ah battery is a compelling budget option.

Designed specifically for Greenworks G-MAX 40V tools, this unit delivers double the runtime of standard 3.0Ah packs.

This capacity makes it perfect for mid-sized lawns and extended trimming sessions. The battery uses premium lithium-ion cells that ensure stable power output and fast charging.

It has a no-memory-effect design, meaning you can recharge it anytime without degrading its lifespan. Furthermore, its low self-discharge rate ensures it stays charged when stored.

This model offers solid build quality and long-term reliability at a fraction of the OEM cost, delivering 90% of the performance of the official Greenworks battery.

Key Features

• 40 Volt and 6.0Ah capacity
• Lithium ion cells with no-memory-effect design
• Compatibility with Greenworks G-MAX 40V Lawn Mower Tools
• FCC, RoHS, and CE certifications confirming safety standards
• Low self-discharge rate

Pros

• Full Greenworks compatibility
• Budget-friendly price point (greatest capacity at less than half the price of OEM 4.0Ah)
• Delivers double the runtime of standard 3.0Ah packs
• Ensures stable power output and fast charging

Cons

• Lacks an onboard LED indicator or fuel gauge
• Limited heavy-load performance
• May struggle with high-drain applications like dual-blade mowers or wet grass under continuous load

5. 2-Pack 6.0Ah OP40601 Replacement: Best Value 2-Pack

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For Ryobi users who value convenience and redundancy, this 2-pack of 6.0Ah batteries is a smart investment that ensures uninterrupted productivity.

Offering two high-capacity batteries, it is the most cost-effective way to double your runtime and virtually eliminate downtime.

Each battery provides 6,000mAh of power, sufficient for mowing, trimming, and blowing without constant recharging.

The construction uses top-grade A-cells to ensure stable voltage and optimized communication with Ryobi tools and chargers, which helps reduce charging issues and error codes common with cheaper clones.

Testing confirmed that one battery easily handles a 1/2 acre yard, allowing the second unit to be ready for seamless rotation. This 2-pack offers the best balance of value, capacity, and practicality.

Key Features

• 40V MAX and 6000mAh capacity per battery
• Comes in a 2Pack packaging
• Compatible with Ryobi 40-Volt tools (e.g., OP4050A, OP4015, OP4026)
• Top-grade A-cell construction

Pros

• Excellent 2-pack value for maximum uptime
• Most cost-effective way to double runtime
• Tool and charger compatible (fits OP401 and ZROP401 chargers)
• Good cycle retention over time

Cons

• Inconsistent LED presence (some units may lack the 4-light display)
• Not high-output rated
• Does not offer high-output performance for heavy-duty tools like chainsaws or snow blowers

6. Greenworks Genuine 4.0Ah Battery: Best Genuine Brand

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As the genuine Greenworks OEM battery, this 4.0Ah pack sets the gold standard for reliability, integration, and support.

While its capacity is lower than third-party 6.0Ah clones, its optimized cell chemistry and system-wide communication guarantee seamless performance across all Greenworks 40V tools.

A major benefit is the 1-hour rapid charge time, which lets you get back to work faster than most clones allow.

This is combined with an integrated 4-LED fuel gauge and a robust 3-year warranty, making it the most trustworthy option for long-term ownership.

It delivers consistent, stable power without unexpected shutdowns, even when using high-drain tools like dual-blade mowers.

For users who prioritize peace of mind, brand integrity, and long-term support, this battery delivers unmatched confidence and performance consistency.

Key Features

• Genuine Greenworks OEM battery
• 40V and 4.0Ah capacity
• Compatibility with 60+ Tools in the Greenworks ecosystem
• Fast charge time: 1 hour (rapid) or 2 hours (standard)
• Comes with a full 3 Year Warranty

Pros

• Genuine OEM quality with superior build quality
• Excellent integration and diagnostic precision within the Greenworks ecosystem
• Industry-leading 3-year warranty and support
• Integrated 4-LED fuel gauge

Cons

• Lower 4.0Ah capacity limits runtime compared to 6.0Ah models
• Higher upfront cost
• Lack of heavy-duty thermal management means it can overheat under prolonged high load, sometimes requiring cooldown periods

7. Wild Badger 4.0Ah 40V Battery: Best Lightweight Option

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The Wild Badger 40V 4.0Ah battery is the lightest and most portable option in this selection, perfect for users who prioritize comfort and ease of use.

Weighing noticeably less than 6.0Ah clones, it significantly reduces fatigue during extended edging or trimming sessions.

Despite its compact size, it delivers solid 4.0Ah performance, which is sufficient for small to medium yards. It features minimal self-discharge, ensuring it is ready when needed.

Its tool-agnostic design supports compatibility across multiple brands (like Greenworks and Ryobi trimmers), making it ideal for households with mixed toolkits.

The real-time LED charge monitor provides instant feedback. This battery excels in light to moderate applications where ergonomic performance matters most.

Key Features

• 40 Volt and 4.0Ah capacity
• Lithium-Ion with a lightweight design feature
• Compatibility with String Trimmers, Leaf Blowers, Lawn Mowers & More
• Features a real-time LED charge monitor
• Minimal self-discharge

Pros

• Lightweight design reduces operator fatigue
• Cross-tool compatibility (works with Greenworks and Ryobi tools)
• Affordable price point compared to OEM 4.0Ah models
• Quick-swap design makes transitions between tools effortless

Cons

• Shorter runtime due to 4.0Ah capacity
• No rapid charge capability
• Struggles on larger lawns or high-drain tools, potentially requiring mid-job swaps
• Lacks advanced thermal protection (can overheat during back-to-back use)

8. KUNLUN 6.0Ah 40V Battery: Best for Durability

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The KUNLUN 6.0Ah 40V battery is built for long-term durability and daily reliability, making it a top contender for users who require consistent performance and rugged construction.

It boasts a 6000mAh capacity and claims 500+ charge cycles, designed to outlast cheaper clones. This unit features over-molded edges for enhanced impact resistance and usability.

It provides stable power across all compatible Ryobi 40V tools. Safety is confirmed by CE, FCC, and RoHS certifications.

Furthermore, it includes a built-in protection suite—guarding against overcharge, overheat, and short-circuit—which ensures long-term battery and tool safety.

The KUNLUN offers OEM-like quality at a fraction of the cost and is ideal for users seeking a durable, high-capacity battery without high-output pricing.

Key Features

• Lithium ion cells with 6000mAh capacity (240Wh)
• 40V standard voltage
• Compatible with Ryobi 40V models (e.g., OP4026, OP4030, OP4040, etc.)
• Durable construction with over-molded edges
• Includes a 4-LED battery life indicator

Pros

• Excellent build quality and claims of 500+ charge cycles
• Comprehensive over-protection suite built-in for enhanced safety
• Consistent and stable performance for reliable everyday use
• No compatibility issues or error codes when charging on Ryobi chargers

Cons

• Slower charging than OEM options
• Average cold-weather performance
• Housing feels less premium compared to genuine alternatives

Buying Guide: Choosing the Right 40 Volt Battery for Your Lawn Mower

A reliable 40V battery is crucial for maintaining your lawn, but selecting the correct one can be challenging given the numerous options. Here is a detailed breakdown of the key features you must consider to maximize performance and longevity:

1. Amp-Hour (Ah) Capacity: Runtime is Key

The Amp-hour (Ah) rating is the most important factor, as it dictates how long your lawn mower (or other tools) will run on a single charge; a higher Ah rating means longer runtime.

• 4.0Ah: This capacity is suitable for smaller yards and light-duty tasks, offering a good balance between weight and runtime.
• 6.0Ah: This is considered a great all-around choice for medium-sized yards or handling heavier tasks like cutting thick grass. It provides significantly more runtime than 4.0Ah batteries.
• 7.5Ah (or higher): This capacity is best for large yards, demanding jobs, or for users who want to minimize interruptions for recharging. However, these higher-capacity batteries will be heavier.

If you regularly tackle tough weeds or a large area, investing in a higher Ah battery is highly recommended.

2. Compatibility: Ensuring a Proper Fit

40V batteries are not universally compatible; most are designed to work only with specific brands. Always confirm compatibility with your lawn mower model before purchasing to avoid damaging your equipment or the battery itself.

• Ryobi 40V: This is a very popular system, and many aftermarket options are available. Ensure the battery specifically states compatibility with Ryobi 40V tools and lists the compatible models.
• Greenworks 40V: This is another common system. Again, confirm compatibility with Greenworks 40V tools.
• Universal (Limited): While some batteries claim wider compatibility, you must carefully check the list of supported tools to verify that it will work with your equipment.

3. Features for Convenience and Longevity

Beyond basic capacity and fit, certain features enhance safety and the overall user experience:

• LED Charge Indicator: This is a crucial feature that allows you to quickly check the battery’s remaining charge level. Four-LED indicators (representing 25%, 50%, 75%, 100%) are preferable for accurate monitoring.
• Battery Protection Circuitry: Look for batteries with built-in protection against overcharging, overheating, over-discharge, and short circuits. This feature extends the battery’s lifespan and enhances safety. Failure rates are higher in batteries without this integrated circuitry.
• Weight: Keep in mind that higher Ah batteries are heavier. Consider this factor if you have difficulty maneuvering your lawn mower.
• Temperature Operation: Batteries with specialized thermal management can operate reliably in extremely cold or hot conditions, as lithium-ion performance can degrade significantly without it.

To extend the life of your 40V battery, remember to avoid overcharging, overheating, and complete discharge, and store the battery in a cool, dry place when not in use. Investing in a battery with robust protection circuitry will also significantly increase its longevity.