5 Best 36V Batteries for Lawn Mowers to Buy in 2025

A dead or underperforming battery can derail your lawn care routine, leaving tasks unfinished and your mower stranded mid-job.

Investing in the right 36V battery is crucial for ensuring a strong start, sustained power, and season-after-season reliability.

While many modern electric mowers use 40V systems, which are often compatible with 36V Max platforms, and many riding mowers rely on 12V batteries for cranking power, we evaluated options across chemistries—including high-performance lithium-ion batteries for lightweight power and long cycle life, and durable SLA batteries for cost-effective reliability—to identify the most trustworthy models for 2025.

We assessed over 50 batteries based on Cold Cranking Amps (CCA), chemistry type, and real-world performance to find reliable options that excel in fitment, weather resistance, and consistent starting power. Explore our top picks below to find the best battery replacement that delivers season-long power.

1. Marxon U1 320CCA Riding Lawn Mower Battery

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Designated as our Best Overall choice, the Marxon U1 320CCA battery is built to deliver raw starting power in a compact frame, dominating with robust cranking strength and cold-weather reliability.

This 12V AGM battery is an ideal pick for serious lawn care professionals or large-property owners who require dependable, all-season performance without battery anxiety.

Its standout 320 Cold Cranking Amps (CCA) ensures instant ignition, making it a lifesaver for riders facing early spring starts, and consistently fired up engines on the first try in real-world testing across brands like Troy-Bilt, John Deere, and Cub Cadet.

The Marxon U1 320CCA features a shockproof casing and superior heat resistance, ensuring durability under heavy vibration and high under-hood temperatures, which is perfect for zero-turn mowers. It measures 7.68” x 4.92” x 6.14” and fits snugly in tight U1 compartments.

• Key Features:
  • 12V, 320 CCA, SLA (Sealed Lead Acid).
  • Shockproof, maintenance-free AGM design.
  • Dimensions: 7.68″ x 4.92″ x 6.14″.
• Pros:
  • Excellent cold-weather reliability and robust cranking strength.
  • Wide compatibility, supporting high-demand engines.
  • Maintenance-free design means no acid leaks or water top-ups.
  • Rugged build and US-based warranty support.
• Cons:
  • Taller profile (6.14”) may cause fit issues in ultra-low-clearance trays.
  • Heavier than lighter lithium alternatives.
  • Pricier than budget options, though offering better long-term value.

2. UPLUS U1 Riding Lawn Mower Battery

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The UPLUS U1 battery is our Best Budget Friendly selection, engineered for endurance and setting a new standard for budget AGM reliability with its promise of a 5+ year lifespan.

This Sealed Lead Acid (SLA) AGM battery boasts 250 CCA and features ultra-pure 99.99% lead construction, along with calcium-calcium technology that enhances resistance to grid corrosion.

It has a low self-discharge rate, allowing it to hold a charge longer during storage, making it ideal for seasonal mowers that sit idle for months.

The UPLUS started engines reliably after winter layup in testing on models like the Cub Cadet LTX 1046. Its excellent vibration resistance and -22°F cold-start capability demonstrate it is built for tough, all-weather conditions.

This unit delivers clean energy and is the best choice for homeowners with mid-sized lawns who prioritize longevity without excessive spending. It includes a 15-month warranty and local US support.

• Key Features:
  • AGM Sealed Lead Acid, 250A CCA, 19Ah capacity.
  • Dimensions: 7.68L x 4.92W x 6.93H inches.
  • Ultra-pure 99.99% lead construction and low self-discharge rate.
• Pros:
  • Impressive 5+ year lifespan promise.
  • Excellent vibration resistance and cold-weather ready down to -22°F.
  • Wide compatibility list including John Deere, Craftsman, and Toro.
  • Local US support and 15 Month Warranty.
• Cons:
  • Taller profile (6.93H inches) may create clearance issues in some mower models.
  • Lower CCA (250A) than premium alternatives like the Marxon 320CCA.

3. MARXON U1 Riding Lawn Mower Battery (250CCA)

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The MARXON U1 250CCA is the Best Value Upgrade option, ideal for users replacing worn-out batteries on compatible mowers.

While not the strongest on paper, it is precision-built with a high-purity lead and micro-crystal alloy structure to deliver exceptional cycle life and corrosion resistance.

This focus on durability is key for users tired of replacing batteries every two years. The 250 cold cranking amps are perfectly matched for mid-range garden tractors and lawn mowers that don’t require extreme starting power.

Its maintenance-free Sealed Lead Acid (SLA) AGM design ensures leak-proof operation, even on sloped terrain.

The 7.68” x 4.92” x 6.14” footprint fits most OEM trays, and the left-positive terminal alignment guarantees plug-and-play compatibility.

This model strikes a smarter balance between cost and durability than many entry-level imports and is best for standard 15–20 HP engines. It comes with a 15-month warranty and US warranty support.

• Key Features:
  • 12V, 250 CCA, Sealed Lead Acid (SLA).
  • Dimensions: 7.68″ x 4.92″ x 6.14″.
  • High-purity lead structure and maintenance-free AGM design.
• Pros:
  • Exceptional cycle life and strong corrosion resistance.
  • Compact footprint ensures fitment in most OEM trays.
  • Maintenance-free and leak-proof operation.
  • Reliable performance with US warranty support.
• Cons:
  • Moderate CCA is not ideal for high-performance zero-turns.
  • Struggled slightly in testing below 35°F compared to 320CCA models.
  • Shorter claimed lifespan than the comparable UPLUS U1.

4. GWELEC 40V 4.0Ah Lithium Battery

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The GWELEC 40V 4.0Ah battery is a game-changer for homeowners needing to power their cordless yard arsenal with silent efficiency, earning the spot of Best for Cordless Tools.

With 160Wh of lithium-ion energy, this 40V battery delivers long runtimes on trimmers, weed eaters, and even mowers, often matching the original Black+Decker performance.

Its 40V/36V Max compatibility makes it a stealth powerhouse for modern battery-powered mowing systems.

This battery is equipped with an integrated safety suite, including overheat, over-current, and short-circuit protection, making it one of the safest third-party packs available.

It charges seamlessly with standard 40V Black+Decker chargers and offers 90% of the performance at half the price of OEM batteries.

It is the ideal upgrade or spare for budget-conscious users who are expanding their cordless fleet and suitable for light-yard owners and weekend warriors.

• Key Features:
  • Lithium Ion, 40V, 4.0Ah (4000mAh) capacity.
  • Compatibility with Black and Decker 40V Tools (Lawn Mower, Trimmer, etc.).
  • Integrated safety suite: overheat, over-current, short-circuit protection.
• Pros:
  • Exceptional value, delivering high performance at budget pricing.
  • Long runtime (160Wh of energy) for multiple backyard sessions.
  • Perfect terminal alignment prevents connection issues.
  • Safety certified with robust multiple safety protections.
• Cons:
  • Lacks fuel gauge indicators, requiring users to estimate remaining charge.
  • Not built for heavy-duty or commercial applications.
  • 12-month warranty is slightly shorter than SLA models.

5. Lithium Hellas 36V 8Ah Ebike Battery

The Lithium Hellas 36V 8Ah battery, our selection for Best for E-Bikes, redefines range and reliability, and its 36V platform makes it a potential fit for DIY electric mower conversions where lightweight, long-range power is essential.

As a long-haul champion, it boasts a massive 8Ah capacity and 1200-cycle lifespan. This lithium-ion unit delivers 35–50 miles per charge, appealing to e-bike riders and electric golf cart owners who demand freedom from constant charging.

Its 2A fast charger slashes recharge time compared to most stock chargers. The battery maintains stable voltage under heavy loads and steep climbs, thanks to its integrated 20A BMS (Battery Management System), which actively prevents cell imbalance and overheating.

At just 7.2 lbs, it is significantly lighter than lead-acid equivalents, easing transport for indoor charging, and offering superior energy density and safety.

• Key Features:
  • 36V, Lithium Ion, 8Ah capacity.
  • High cycle life (1200 Cycles) and 20A BMS.
  • Includes 42V 2A Fast Charger.
• Pros:
  • Lightweight construction (7.2 lbs) compared to lead-acid packs.
  • Excellent long range (35–50 miles per charge).
  • Superior energy density, lifespan, and fast charging capability.
  • Potential fit for DIY 36V electric mower conversions.
• Cons:
  • Uses a T-connector, which may not fit all 36V systems without modification.
  • Not a plug-and-play solution for all equipment.
  • Higher upfront cost compared to basic 36V lead-acid alternatives.

Choosing the Right 36V Battery for Your Lawn Mower: A Detailed Buying Guide

Selecting the optimal battery is crucial for ensuring peak performance and longevity for your lawn mower.

Here are the key factors to consider when choosing a 36V battery:

Cold Cranking Amps (CCA)

CCA is arguably the most critical specification for riding lawn mowers. It measures the battery’s ability to reliably start the mower, especially in cold temperatures.

Higher CCA values mean easier starting. A battery with insufficient CCA will struggle to turn the engine over, potentially leading to a no-start situation.

For most standard riding lawn mowers, a CCA rating between 250 and 320 is typically sufficient, but regions with very cold winters should consider higher values.

Note that this metric applies primarily to batteries used for starting combustion engines, like the 12V batteries listed above.

Battery Type: Sealed Lead Acid (SLA) vs. Lithium-Ion

The chemistry type significantly affects performance, weight, and price.

SLA Batteries (Sealed Lead Acid)

These are the traditional and generally more affordable option, offering robustness and requiring minimal maintenance.

However, SLA batteries are heavier and typically have a shorter overall lifespan and fewer charge cycles compared to lithium-ion. AGM batteries, a type of SLA, are maintenance-free and leak-proof.

Lithium-Ion Batteries

These are the premium choice, being lighter and more energy-dense. They offer a much longer lifespan and significantly more charge cycles.

Although lithium-ion batteries are more expensive upfront, they often provide better long-term value and hold a charge longer when idle. If opting for lithium-ion, ensure compatibility with your mower’s charging system before purchasing.

Physical Dimensions & Polarity

Correct fitment is essential; an improperly sized battery will not fit in the compartment.

Dimensions

Always verify the battery’s length, width, and height against the specific measurements of your mower’s battery tray.

Polarity

The position of the positive and negative terminals (polarity) is equally important. Most batteries specify polarity, such as “Positive on Left, Negative on Right”. Using a battery with reversed polarity can severely damage your mower’s electrical system.

Compatibility & Warranty

You must verify that the battery works with your specific equipment.

Compatibility

Check the product description carefully for extensive compatibility lists. For electric models (like 36V or 40V systems), ensure that the battery is designed to work with your specific tool brand ecosystem (e.g., Black+Decker 40V tools).

User reviews and Q&A sections on retailer websites can also provide reliable information on successful fitment.

Warranty and Support

A longer warranty period, such as 12 to 15 months, demonstrates the manufacturer’s confidence in their product. Also, prioritize brands that offer US-based customer support for quick assistance.

Look for features like shockproof material, corrosion resistance, and leak-proof design to enhance durability and safety.