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Monster Marine Lithium | 1500 CCA 300AH Dual Purpose Cranking Lithium Bluetooth "Sea Lion"

1500 CCA 300AH Dual Purpose Cranking Lithium – Bluetooth "Sea Lion"

Unmatched Power. Ultimate Reliability. Compact Size.

The Sea Lion is our most compact, energy-dense dual-purpose lithium battery ever. Designed for serious offshore and tournament anglers, it delivers an industry-leading 1500 Cold Cranking Amps (CCA) and an impressive 300Ah of capacity, making it a top-tier choice for starting your engine and powering your entire electronics setup—all from one battery.

Tested. Proven. Trusted.

A question we’re asked often is: “Will it work with my engine?”
The answer is yes—without a doubt.

We’ve personally tested this battery over years on boats owned by family, friends, and tournament pros. After over a year of real-world use, it has consistently delivered dependable performance across a wide range of engines, including:

  • Mercury Pro XS 4-Stroke & 2-Stroke

  • Yamaha 4-Stroke & SHO (both old and new models)

  • Yamaha HPDI

  • Mercury Verado 4-Stroke

  • Suzuki 4-Stroke

  • Evinrude 2-Stroke

  • Mercruiser 4-Stroke

Built for Demanding Marine Systems

From high-draw electronics to cranking power-hungry outboards, the Sea Lion handles it all:

  • 1500 CCA for confident starts in any weather

  • 300Ah capacity for extended runtime

  • Advanced BMS (Battery Management System) for safety, stability, and performance

  • Bluetooth Monitoring via iOS & Android app for real-time status updates

  • Grade A LiFePO4 Cells for maximum longevity and cycle life

Perfect For Power-Heavy Setups

Whether you're running:

  • 6 to 10 Graphs

  • Mega 360

  • Multiple Livescopes

  • Shallow Water Anchors

  • Bait Tanks

  • Pumps

  • Marine Lighting Systems

...this battery can handle all of it with ease.

Installation & Compatibility

  • Group 31 case – Drop-in ready

  • Plug-and-play wiring

  • Connect up to 4 in series for 24V, 36V, or 48V systems

  • Parallel capable for even more capacity

  • Compatible with all AGM-mode chargers including:

    • Minn Kota (Precision & Digital)

    • Dual Pro

    • NOCO

    • Real Pro

    • Pro Sport

All chargers must have AGM charging capability.

Specification

Weight

56 lbs 

CCA

1500 cold cranking amps

Size Dimensions

L 13.5 in (343mm) x W 7.25in (184mm)  x H 9.75 in (247mm)

Voltage

12.8V

Energy

3840 Watts (Wh)

Amp-Hours

300Ah 

Charge Volts

14.4-14.6v

Continuous Amps

300A max

Terminals

Top Post & M8

 

**SAFETY-INSPECTED CYLINDERS** Ships FREE, Fast, & Insured

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**RELIABLE COMMERCIAL STOCK** Expert Vetted

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**FULL REGULATORY COMPLIANCE** USA & International

Why Shop With Us?

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Fast & Free Shipping

Enjoy free, fast delivery on all orders. Your products will be dispatched within 48 hours.

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30-Day Guarantee

Not satisfied? We offer a hassle-free 30-day money-back guarantee on all our products.

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Guaranteed Purity & Performance

We provide certified gas with 99.9% minimum purity, preventing system contamination and ensuring optimal HVAC function.

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