NOCO NLX27 Group 27 Lithium Dual-Purpose Marine Battery

The NOCO NLX27 is a Group 27 lithium dual-purpose marine battery, and it's built to do the work of two batteries at once. It delivers the strong burst of current needed to crank your engine, then turns around and provides steady, deep-cycle power to run your electronics, trolling motor, lights and stereo through a full day on the water. For many boaters that means one battery can handle both starting and house duty, cutting weight and clutter without giving up performance.

It all comes down to the chemistry. The NLX27 is built on lithium iron phosphate (LiFePO4) cells, widely regarded as the safest and most stable lithium chemistry for marine applications. Against traditional lead-acid, LiFePO4 delivers much more usable capacity from the same footprint, a flat voltage curve that keeps your gear running strong until the battery is nearly depleted, and far longer service life. This battery is rated for roughly 2,000 cycles at 100 percent depth of discharge, 4,000 cycles at 80 percent, and an impressive 10,000 cycles at 50 percent. That's the kind of longevity that pays for itself over years of use.

Capacity comes in at 100 amp-hours, or 1280 watt-hours, and because it's lithium, nearly all of that is usable rather than the roughly half you'd trust from a lead-acid deep-cycle. On the starting side, the NLX27 puts out 1400 amps of peak cranking current, so it spins over outboards and inboards with ease, even when it's cold. That blend of reserve capacity and cranking muscle is exactly what a dual-purpose marine battery is supposed to deliver.

Watching over everything is an advanced Battery Management System (BMS). It protects the cells against over-charging, over-discharging, over-current, short circuits and cell imbalance, and it continuously monitors temperature to guard against extreme heat and cold. The BMS uses bi-directional active cell balancing to keep every cell working together, which preserves capacity and extends life, and it requires no manual reset to bounce back from a protection event. You get all the upside of lithium without the fuss.

NOCO engineered the NLX27 for the realities of boating. The case is rated IP66, so it resists dust and strong water jets, and it operates across a wide -4 to 122 degrees F (-20 to 50 degrees C) range that spans cold launches and hot engine bays alike. It weighs just 28 pounds, dramatically less than the lead-acid battery it replaces, which lightens your load and makes carrying and mounting far easier. The case measures 12.05 inches wide, 6.81 inches deep and 8.03 inches tall, matching the standard Group 27 footprint so it fits common battery trays.

Wiring is easy to adapt thanks to the included terminal options. You get SAE posts, 3/8-24 threaded terminals, and 3/8-24 by 5/16-24 threaded terminals, along with the bolts, nuts, covers and hex keys to install them, plus a removable handle for carrying. That flexibility lets the NLX27 work with your existing cable setup rather than forcing a rewire. When it's time to recharge, use a charger that's rated for lithium iron phosphate batteries to get the fastest, safest results.

We'd recommend the NLX27 for the boater who wants a lighter, longer-lasting, do-it-all battery in a Group 27 size. It cuts weight, adds usable reserve, and stops the every-couple-of-seasons battery replacement cycle that lead-acid owners know too well. Backed by a 5-year limited warranty and shipping with everything you need to install it, it's a straightforward upgrade that pays off every single trip.

Picture a long day on the water with the NLX27 aboard. You run your electronics hard, spend hours at anchor with the stereo going, and never once think about whether there's enough left to start the engine. The flat lithium voltage holds your gear at full strength instead of dimming as the charge drops, and when you're ready to head home the engine cranks strong. That's the freedom a good dual-purpose lithium battery gives you, and it's exactly what the NLX27 was designed to do.