{"product_id":"2-pack-3-7volt-rechargeable-battery-3-7v-lithium-batteries-2500mah-high-capacity-for-led-flashlights-headlights-small-fans","title":"2500mAh 3.7V 18650 Li-ion Rechargeable Battery (2-Pack) – High Capacity for LED Flashlights, Headlamps \u0026 Portable Fans","description":"\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eThe Everyday Power Upgrade\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eWhy settle for standard when you can have 25% more? Each cell in this 2‑pack stores a genuine 2500mAh — that’s 9.25 watt‑hours of energy, noticeably extending the runtime of your LED flashlights, headlamps, and portable fans compared to the common 2000mAh battery. It’s the intelligent upgrade for people who use their gear daily: the pocket torch that lights your way home, the headlamp that guides your evening run, the desk fan that hums through a long work shift. With two identical cells, you’ll always have a fully charged spare ready to swap — zero downtime, double the peace of mind.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eUnprotected Design: Shorter, Lighter, More Efficient\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eWe deliberately leave off the external protection PCB to create a cell that’s as compact and electrically pure as possible. At just 65.0mm (flat top) or 66.5mm (button top), these batteries slip effortlessly into tight flashlight tubes, slim headlamp compartments, and recessed fan battery bays that simply cannot accommodate the extra length of a protected cell. Removing the PCB also eliminates an extra layer of resistance, so more stored energy reaches your device and less is wasted as heat. The trade‑off is small: you must use a quality charger that stops exactly at 4.2V, and only install the cell in devices with built‑in low‑voltage cutoff — a standard feature in virtually all modern LED lights, headlamps, and USB‑rechargeable fans.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eChoose Your Terminal: Button Top or Flat Top\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eCompatibility should never be a guessing game, so we offer both styles. The \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eButton Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e has a raised positive nipple (~1.5mm) that locks securely into spring‑loaded compartments and easily passes mechanical reverse‑polarity rings — common in many consumer flashlights and headlamps. The \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eFlat Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e has a completely flush positive end, essential for devices with ultra‑tight battery tubes, for spot‑welding custom DIY battery packs, and for gadgets with pogo‑pin or flat PCB contacts. Check your manual, pick the right version, and enjoy a wiggle‑free connection every time.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eWhere 2500mAh Makes All the Difference\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eRated for a continuous discharge of up to 5A (2C), this cell is optimized for medium‑drain devices — exactly the profile of the flashlights, headlamps, and fans it’s designed for. In a compact LED flashlight, expect around 2.5 hours of bright 300‑lumen output, or over 8 hours on a gentle low mode. A lightweight headlamp will easily power a full night of reading, camping, or trail running on a single charge. A USB portable fan will hum on low speed for 6–8 hours, keeping you cool through a workday or a hot summer night. And because you have two batteries, you can keep one in use and one on standby — no waiting for a recharge when you need power most.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eBuilt to Endure, Designed for Safety\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eUnder the nickel‑plated steel shell, stable NMC chemistry holds a true 3.7V nominal voltage and a flat discharge curve, so your light doesn’t dim and your fan doesn’t slow until the battery is nearly empty. Despite the lack of an external protection IC, each cell includes a built‑in \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003ePTC thermistor\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e to suppress over‑current spikes and a \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eresealable pressure vent\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e that activates under extreme internal stress. The steel can withstands drops, corrosion, and daily abuse. With over 500 full charge cycles and very low self‑discharge, you can store a spare for months at the recommended voltage, and it will wake up ready for the next adventure.\u003c\/span\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eKey Features\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eGenuine 2500mAh High Capacity (9.25Wh per cell)\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003e25% more energy than a standard 2000mAh battery. Delivers up to 2.5 hours of flashlight high‑mode light, 8+ hours of headlamp glow, or all‑day fan cooling.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e2‑Pack for Uninterrupted Use\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eTwo identical cells. Keep one in your device, one fully charged in your bag. Perfect for extended trips, long shifts, or power outages.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eUnprotected, Ultra‑Compact Form\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eShorter than protected cells (65.0mm flat \/ 66.5mm button) to fit the tightest battery compartments. Lower overall resistance means more efficient power delivery and less heat.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eDual Terminal Options: Button Top \u0026amp; Flat Top\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eButton Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e for a secure click in spring‑contact devices. \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eFlat Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e for recessed contacts, welded packs, and ultra‑tight tubes. No adapters, total compatibility.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eStable NMC Chemistry \u0026amp; Flat Discharge\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eMaintains a consistent 3.7V from 4.2V down to 2.5V. Your light stays bright, your fan speed remains steady, and your headlamp performs predictably.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eLow Internal Resistance (≤75mΩ)\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eMinimal voltage sag under load. At a 5A draw, voltage drops by only 0.375V; on typical 1–3A loads, the drop is barely noticeable.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e500+ Cycle Life \u0026amp; Low Self‑Discharge\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eRecharge each cell over 500 times with minimal capacity fade. Store the spare at 3.6–3.7V for months; it will still be ready when you need it.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eBuilt‑In Passive Safety\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eIntegrated PTC thermistor and resealable safety vent provide foundational protection. Rugged steel can resists drops, leaks, and corrosion.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eEco‑Friendly \u0026amp; Cost‑Effective\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eReplaces hundreds of disposable alkalines. Zero memory effect lets you recharge at any state without conditioning.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eTechnical Parameters\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cdiv class=\"ds-scroll-area ds-scroll-area--show-on-focus-within ds-scroll-area--enabled _1210dd7 c03cafe9\"\u003e\n\u003cdiv class=\"ds-scroll-area__gutters\"\u003e\n\u003cdiv class=\"ds-scroll-area__horizontal-gutter\"\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cspan class=\"\"\u003eParameter\u003c\/span\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cspan class=\"\"\u003eSpecification\u003c\/span\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eBattery Type\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e18650 Li‑ion (unprotected, bare cell)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eNominal Capacity per Cell\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e2500mAh (9.25Wh)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003ePack Count\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e2 cells\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eNominal Voltage\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e3.7V\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eFull Charge Voltage\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e4.2V ± 0.05V\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eDischarge Cut‑off Voltage\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e2.5V (use only with low‑voltage protected devices)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eStandard Charge Current\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e1.25A (0.5C)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eMax Continuous Discharge\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e5A (2C) — optimized for medium‑drain devices\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eMax Pulse Discharge\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e7A (\u0026lt;5 seconds)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eInternal Resistance\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e≤75mΩ (AC 1kHz, bare cell)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eProtection Circuit\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e\u003cspan class=\"\"\u003eNone\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e — requires external over‑discharge protection\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003ePositive Terminal Options\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e\u003cspan class=\"\"\u003eButton Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (raised ~1.5mm) or \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eFlat Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (flush)\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eDimensions (Button Top)\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 18.3mm dia. × 66.5mm length\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eDimensions (Flat Top)\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 18.3mm dia. × 65.0mm length\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eWeight (Button Top) per cell\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 45g\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eWeight (Flat Top) per cell\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 44g\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eCycle Life per cell\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e≥500 cycles (≥70% initial capacity at 0.5C)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eOperating Temp. (Charge)\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e0°C to 45°C\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eOperating Temp. (Discharge)\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e-20°C to 60°C\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eStorage Temp. \u0026amp; Humidity\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e-5°C to 35°C, \u0026lt;75% RH (recommend 3.6–3.7V storage)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eChemistry\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eNMC (Lithium Nickel Manganese Cobalt Oxide)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003chr\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eApplications\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e1. LED Flashlights \u0026amp; EDC Torches\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003ePerfect for daily‑carry lights, tactical torches, and compact throwers. The 2500mAh capacity provides approximately 2.5 hours on a 300‑lumen medium mode, or a full night on low. Flat top fits ultra‑tight enthusiast tubes; button top secures firmly in spring‑loaded hosts. Keep the spare in your pocket for instant swaps during extended use.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e2. Headlamps for Work \u0026amp; Play\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eWhether you’re a trail runner needing hours of light, a mechanic working under a vehicle, or a camper reading in a tent, the 2500mAh cell won’t let you down. At 100 lumens, expect 7–8 hours of hands‑free illumination. The cell’s moderate weight keeps the headlamp balanced and comfortable.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e3. Portable Fans for All‑Day Cooling\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eUSB desk fans, stroller fans, and camping fans run beautifully on this cell. Low speed delivers 6–8 hours of gentle breeze; high speed offers 1.5–2 hours of strong airflow. Two cells let you swap and stay cool around the clock. Flat top is often required for recessed fan battery bays.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e4. Camping Lanterns \u0026amp; Outdoor Lights\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eCompact lanterns and tent lights benefit from the 9.25Wh energy reserve, providing a full night of illumination. Keep the spare cell in your pack for multi‑day adventures.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e5. DIY Battery Packs \u0026amp; Hobby Projects\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eThe flat top variant is ready for spot welding into 2S or 3S packs for Bluetooth speakers, IoT sensors, or Arduino robots. Unprotected design gives you full control over your BMS.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e6. Emergency Backup Power\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eStore a few charged cells in a waterproof case for blackouts, storms, or road trips. Their low self‑discharge ensures they’re ready when the grid isn’t.\u003c\/span\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eFAQ\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ1: Is 2500mAh a high capacity? How much better is it than 2000mAh?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Yes, it offers a genuine 25% capacity boost over standard 2000mAh cells. In practice, a flashlight that lasts 2 hours on a 2000mAh battery will run for about 2.5 hours on this 2500mAh cell — a noticeable improvement for everyday use.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ2: Why is this battery unprotected? Is it safe for my flashlight?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: We omit the protection PCB to shorten the cell (fits more devices) and to reduce internal resistance. It’s completely safe when you use a quality 4.2V Li‑ion charger and only install it in devices with built‑in low‑voltage cutoff — which most modern flashlights, headlamps, and USB fans already have. The cell also includes a PTC thermistor and a safety vent for passive protection.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ3: How do I choose between Button Top and Flat Top?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: If your device’s positive contact is a spring with a plastic ring around it, you likely need a \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eButton Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e for firm contact. If the battery tube is extremely tight or the contact is a flat metal pad, you need a \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eFlat Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e. For building welded packs, always choose flat top.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ4: Can I use this battery in a high‑drain RC car or power tool?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: No. This cell is rated for a maximum continuous discharge of 5A, perfect for flashlights, headlamps, and fans. RC cars and power tools often demand 10–30A, which would overheat this battery and cause damage. For those, choose our dedicated high‑rate cells.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ5: How long will a 2500mAh battery run my portable fan?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: On low speed (~0.5A), about 5–6 hours; on high speed (~1.5A), roughly 1.5–2 hours. The 2‑pack lets you swap cells and keep the air moving continuously.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ6: How should I store the spare battery?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Keep it in a plastic case, away from metal objects. For storage longer than a month, charge or discharge to about 3.6–3.7V (~50%). Check voltage every 3 months and recharge if below 3.0V. Never store a fully depleted cell.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ7: How many times can I recharge these batteries?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Over 500 full cycles while retaining ≥70% capacity. For a device recharged weekly, that’s nearly a decade of service.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ8: Can I take these on a plane?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Yes. At 9.25Wh per cell, they are well under the 100Wh IATA limit. Carry them in hand luggage with terminals insulated.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ9: What charger should I use?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: A charger specifically designed for 3.7V Li‑ion batteries that terminates at 4.2V. A basic smart charger from Nitecore, XTAR, or LiitoKala is perfect. Never use a NiMH or alkaline charger.\u003c\/span\u003e\u003c\/p\u003e","brand":"DOUBLEPOW","offers":[{"title":"Button Top","offer_id":51454082547958,"sku":"5550DLP55","price":6.88,"currency_code":"USD","in_stock":false},{"title":"Flat Top","offer_id":51454082580726,"sku":"5550DLP56","price":6.58,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0819\/2753\/6886\/files\/2pack-2500mAh-lithium-batteries-flashlight-fan-main_de858500-c1b3-4918-b09f-2240d317c995.webp?v=1786964715","url":"https:\/\/oneandes.com\/products\/2-pack-3-7volt-rechargeable-battery-3-7v-lithium-batteries-2500mah-high-capacity-for-led-flashlights-headlights-small-fans","provider":"OneAndes","version":"1.0","type":"link"}