NL1840R (18650 - 4000mAh - 6A)

An 18650 that charges itself, straight from any USB-C cable. A 4,000mAh protected 18650 with a built-in USB-C port, so a power bank or a phone charger tops it up with no separate charger needed. 4,000mAh, 3.6V, 14.4Wh of energy, roughly four times a CR123A Built-in USB-C port charges directly from a cable or a power bank Red light while charging, green when it is full 6A maximum continuous discharge for high-drain lights Intelligent protected circuit plus a pressure-relief valve for safety Rated for over 500 charge cycles, keeping more than 90% capacity The exact cell that powers the Nitecore UT6 headlamp Charge it with the cable already in your bag. The USB-C port is built into the cell itself, so a wall charger, a laptop or a power bank brings it back to full. Pack one cable for your phone and the same one tops up this battery. A small light on the cell tells you where you stand. Red stays on while it charges, and it turns green the moment it is full, so you can leave it and check at a glance. Two ways to charge, whichever suits the day. Charge it in place over USB-C when you are travelling light, or drop it into a Nitecore charger when you are topping up a few cells at home. Both routes get you to a full battery. On the trail or in a hotel room, plug it into a power bank and keep moving. The flexibility means you are never tied to one charger or one socket. 4,000mAh, about four times a CR123A. With 4,000mAh and 14.4Wh on board, this cell holds roughly four times the energy of a single CR123A. That is longer runtime per charge in a compatible light, and fewer swaps on a long night out. The 6A maximum continuous discharge keeps high-drain lights fed at their brighter modes, so the output you bought for is the output you get. WHY A SELF-CHARGING CELL OVER A STANDARD 18650 PLUS CHARGER No separate charger to pack The USB-C port is in the cell, so any cable you already carry tops it up. A standard 18650 needs its own dock to come back to life. Top up from a power bank Run a cable from a pocket power bank and refill it anywhere. An ordinary cell waits until you are back at a mains socket. Protected and built to last An intelligent protected circuit, a pressure-relief valve and steel end protectors guard every charge. Many bare cells ship with none of this. A charge state you can read The red and green indicator shows charging and full at a glance, so you load a known-full cell. A plain battery leaves you guessing. A MULTI-LAYER PROTECTION SYSTEM Inside the cell sits an intelligent protected circuit built around a purpose-designed, high-performance protection IC. It guards against overcharge, over-discharge and short-circuit, while a high-power MOS-FET regulates current under load. The result is steady, dependable power on every cycle, whether the cell is feeding a bright light or sitting on charge overnight. Built-in safeguards, inside and out. A pressure-relief valve responds to a rapid rise in temperature, releasing internal pressure to keep the cell stable in demanding use. It is the kind of safeguard you want and rarely think about. Together with the protected circuit, these internal features mean the battery looks after itself through hard use and long storage alike. A tough shell that handles daily carry. Nickel-plated stainless-steel protectors cap both ends of the cell, shielding the contacts from knocks and wear in a pack or a pocket. A durable metallic film wraps the body to resist abrasion. It is a cell that takes the rough handling of everyday carry and keeps a clean, reliable connection in your light. Over 500 cycles, with energy to spare. Rated for more than 500 full charge cycles, this cell still holds over 90% of its capacity after 500 rounds. Charge it most days and it keeps delivering for a long time before it fades. It is made mercury-free, lead-free and cadmium-free, so a long-life battery is also a cleaner one to live with and dispose of. WHERE THE NL1840R EARNS ITS PLACE Flashlight Owners A high-capacity 6A cell that keeps a compatible 18650 light running bright, then recharges from any USB-C cable. Headlamp & UT6 Owners The exact cell that powers the Nitecore UT6 headlamp, ready to refill hands-free over USB-C between runs. EDC & Preparedness A protected spare you can keep topped up from a power bank, ready in a kit or a go-bag using just a USB-C cable. Travelling Light Leave the charger at home and refill the cell in place, using the same USB-C cable that charges your phone. Drops into your Nitecore chargers. When you prefer a dock, the NL1840R works in the Nitecore UMS4, UMS2, Ci4 and Ci2 chargers. Charge it alongside your other cells in a multi-bay charger at the bench. So you have it both ways. Charge in place over USB-C when you are out, or top up a row of cells in a charger when you are home. SPECIFICATIONS Chemistry Li-ion (protected 18650, button-top) Capacity 4,000mAh Nominal Voltage 3.6V Energy 14.4Wh Max Continuous Discharge 6A Charging Built-in USB-C port, or external charger Charge Indicator Red charging / green full Protection Intelligent protected circuit, pressure-relief valve, steel end protectors Cycle Life >500 cycles, >90% capacity retained Dimensions 18.5mm ±0.3 dia × 71.0mm ±0.3 length Weight 51g COMPATIBLE CHARGERS & CERTIFICATIONS Compatible Chargers Nitecore UMS4, UMS2, Ci4, Ci2 Direct Charging Any USB-C cable, including from a power bank Materials Mercury-free, lead-free, cadmium-free End Protectors Nickel-plated stainless steel, both ends Body Wrap Durable metallic anti-abrasion film Certifications CE and further global certifications Warranty 12 months FREQUENTLY ASKED QUESTIONS Will it fit my light that takes a 65mm 18650? Check the length. The NL1840R is 71.0mm long, where a standard 18650 is around 65mm. The extra length houses the built-in USB-C port, so a device built for exactly 65mm cells may be a tight fit or may not close. It works in compatible Nitecore lights and chargers, and it is the exact cell used in the Nitecore UT6 headlamp. If your light specifies a 65mm cell, measure the battery bay before ordering. Do I still need a separate charger? No. The USB-C port is built into the cell, so any USB-C cable charges it directly, including one running from a power bank. If you already own a Nitecore UMS4, UMS2, Ci4 or Ci2, the cell works in those too, so you can use whichever is handier. How do I know when it is fully charged? Watch the indicator on the cell. It glows red while charging and turns a steady green once the battery is full, so you can leave it on charge and check the colour at a glance. What's In The Box 1x NL1840R 18650 Battery - 4,000mAh protected Li-ion cell with built-in USB-C charging port A self-charging 18650 that keeps your light ready and your charger at home. GET YOUR NL1840R NOW