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Product Description
Genius Onboard Waterproof Marine Battery Charger, 15Amp, 12V, 3-Bank (GEN5X3)
Meet the all-new GEN5X3. Similar to the GENM3, only better. It's 37% smaller and delivers 43% more power. It's one of the best performing onboard marine battery chargers that Noco has ever made.

A three-bank onboard battery charger rated at 15-amps (5-amps per bank) for 12-volt batteries, including marine, boat, starter, and deep-cycle batteries. Independently charge and control each battery bank with selectable charging modes - including 12V, 12V AGM, 12V Lithium, and 12V Repair Mode - for all types of lead-acid and lithium-ion batteries.

- NOCO Genius GEN5X3 – a high-performance, IP68 waterproof marine battery charger designed for onboard use in boats, deep-cycle systems, starter batteries and more.
- Delivers a total 15 amps output (5 amps per bank across three independent banks) for 12-volt battery systems – enabling you to charge three separate batteries simultaneously with smart control.
- Equipped with selectable charge modes – including 12 V Wet/Gel/Lead-Acid mode, 12 V AGM mode, 12 V Lithium/LiFePO4 mode (for batteries with a BMS), plus a dedicated 12 V Repair mode to restore old, idle or sulfated batteries.
- Advanced thermal sensor compensation automatically adjusts charge rate to compensate for ambient temperature extremes – preventing over-charging in hot climates and under-charging in cold climates for optimal battery health.
- Able to recover deeply discharged batteries down to 1 volt via Force Mode, making it suitable for hard-to-revive starter or marine batteries.
- Built for real marine environments: fully sealed, vibration-isolated mounting system allows installation in any orientation (even upside-down) and resists shock and noise.
- Rated for batteries up to approximately 120 Ah capacity and built with robust protections (reverse polarity, short circuit, over-temperature, open-circuit) for safe, maintenance-free operation.
- Compact and efficient: smaller footprint than previous models (≈ 37% smaller) while delivering around 43% more power — making it ideal for tight installation spaces on boats, RVs and utility craft.
- Whether you’re maintaining trolling-motor batteries, starting batteries, gel or AGM deep-cycles, or even 12 V lithium packs, the GEN5X3 offers flexibility, reliability and unmatched durability in a marine-ready charging system.
Includes everything you need to get started: charger unit, two self-tapping screws for mounting, safety & warranty documentation; backed by a 3-year limited warranty.

Key Features at a Glance:
- 3-Bank onboard charger for 12 V batteries (starter, deep-cycle, marine)
- Total 15 A output (5 A per bank)
- Modes: 12 V Wet/Lead, 12 V AGM, 12 V Lithium, 12 V Repair
- IP68 waterproof rating – sealed for marine conditions
- Temperature-compensation technology for hot/cold climates
- Force Mode to initiate charging from as low as 1 volt
- Anti-vibration backing & flexible mounting orientation
- Suitable up to ~120 Ah battery capacity
- Protections: reverse polarity, short circuit, overcharge, open-circuit
- Compact size, lightweight design, 3-year warranty
WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.
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