12v 40Ah Deep Cycle Lithium Marine Battery "Viper" - Bluetooth - MML-CW1240B
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⚡ Monster Marine Lithium™ “Viper”
12V • 40Ah Portable Bluetooth Deep Cycle Lithium Battery
Model: MML-CW1240B
Overview
Portable, lightweight, and efficient — meet The Viper, a compact 12V lithium battery built for versatility and reliability.
Weighing only 13 lbs, this battery is perfect for powering your 12V electronics, kayak systems, or outdoor power setups, delivering high performance in a small footprint.
Built with Lithium Iron Phosphate (LiFePO₄) technology, The Viper provides twice the power, a fraction of the weight, and four times the lifespan of traditional lead-acid batteries.
It features Bluetooth monitoring via the MMLithium App (iOS & Android), allowing you to track voltage, state of charge, and overall health in real time.
Installation is simple — a true plug-and-play setup — and up to four batteries can be wired in series for higher voltage systems.
Compact, rugged, and dependable, The Viper is also perfect for ice fishing bundles and mobile power boxes.
Key Features
⚙️ Lightweight, Portable Design
At just 13 lbs, The Viper is built for mobility — ideal for kayaks, ice fishing, go-boats, and small 12V setups.
🔋 Reliable Deep-Cycle Power
Delivers 40Ah of steady 12.8V power — perfect for fish finders, sonar units, and outdoor gear.
📱 Bluetooth Smart Monitoring
Stay informed with real-time tracking through the MMLithium Bluetooth App on your phone.
🧠 Advanced LiFePO₄ Technology
Safe, stable, and durable — with 4000+ charge cycles and consistent voltage output under load.
🔌 Plug-and-Play Setup
Quick and easy installation — connect your power leads, and you’re ready to go. Supports series and parallel wiring for expanded systems.
⚡ Charger Compatibility
Compatible with AGM marine chargers (use AGM setting):
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Minn Kota (Precision & Digital)
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Dual Pro
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NOCO
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Real Pro
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ProSport
⚙️ Specifications
| Category | Details |
|---|---|
| Weight | 13 lbs |
| Dimensions (L × W × H) | 7.5 in × 5 in × 6.5 in (195 × 130 × 154 mm) |
| Nominal Voltage | 12.8 V |
| Nominal Capacity | 40 Ah |
| Energy | 512 Wh |
| Charge Voltage Range | 14.4 – 14.6 V |
| Max Charge Current | 40 A |
| Continuous Discharge Current | 60 A max |
| Battery Chemistry | Lithium Iron Phosphate (LiFePO₄) |
| Cycle Life | 4000+ cycles |
| Terminal Type | M8 Bolt |
| Configuration Options | Up to 4 in series for 48V max / parallel for higher capacity |
| Bluetooth Functionality | Built-in Smart Monitoring via MMLithium App |
⚓ Applications
| Use Case | Compatibility |
|---|---|
| Primary Use | Portable power for 12V electronics, kayaks, and ice fishing setups |
| Voltage Systems | Compatible with 12V, 24V, 36V, and 48V configurations |
| Other Uses | Fish finders, sonar units, power boxes, camping, and outdoor setups |
| Replacement For | 12V AGM or lead-acid batteries |
| Weight Advantage | Roughly 70% lighter than standard batteries |
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