⚡ Monster Marine Lithium™ “Sea Lion”

1500CCA • 300Ah Dual Purpose Bluetooth Cranking Lithium Battery

Model: MML-15300JB

Overview

Introducing The Sea Lion — the ultimate combination of strength, endurance, and intelligent power management.
Engineered for anglers, captains, and offshore professionals who demand all-day performance, this 1500CCA 300Ah Dual Purpose Bluetooth Cranking Lithium Battery delivers unmatched capacity and starting reliability in a surprisingly compact design.

With 1500 cold cranking amps and an incredible 300 amp-hours of energy, The Sea Lion offers multi-day runtime without recharging — making it the ideal solution for high-demand systems with multiple graphs, sonar units, bait tanks, pumps, and lighting setups.

Built to meet and exceed Mercury Marine’s newest specification bulletin, this battery has been extensively tested for years across the industry’s top engines:

• Mercury Pro XS 4-Stroke

• Yamaha SHO & 4-Stroke (new and legacy)

• Yamaha HPDI

• Mercury Verado 4-Stroke

• Suzuki 4-Stroke

• Evinrude 2-Stroke

• Mercury Pro XS 2-Stroke

• MerCruiser 4-Stroke

At just 56 lbs, this battery combines huge energy density with modern efficiency — a perfect fit for serious freshwater and offshore applications alike.

Key Features

⚙️ Dual Purpose Design
Built for both engine cranking and deep-cycle operation, giving you powerful starts and hours of sustained energy for demanding setups.

⚡ Massive Power Output
Delivers 1500 cold cranking amps (CCA) — enough to start even the toughest high-output 4-stroke motors with ease.

🔋 Exceptional Deep-Cycle Capacity
Features 300Ah of energy storage — easily running multiple sonar systems, Livescopes, shallow water anchors, bait tanks, and more.

📱 Bluetooth Smart Monitoring
Monitor voltage, charge levels, and real-time performance through the MMLithium Bluetooth App on your smartphone.

🧠 Advanced BMS System
Built with our most sophisticated Battery Management System (BMS) yet — ensuring stability, protection, and high current tolerance for marine environments.

🧭 Compact Power Density
Despite its massive output, The Sea Lion maintains a compact footprint, fitting into standard Group 31–sized compartments.

🪛 Grade A LiFePO₄ Cells
Constructed using only premium-grade lithium cells for unmatched safety, reliability, and long-term performance.

⚙️ Specifications

⚓ Applications