{"product_id":"delipow-3-6-volt-21700-rechargeable-battery-5000mah-flat-top-battery-15a-large-capacity-batteries-for-led-flashlight-headlamps-etc","title":"Delipow 5000mAh 3.6V 21700 Flat Top Li-ion Battery – 15A Continuous High Capacity for LED Flashlights, Fans, Cameras \u0026 Toys","description":"\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eThe Endurance Specialist with a 15A Kick\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eThe Delipow 5000mAh 21700 flat‑top cell bridges the gap between pure energy storage and high‑current delivery. It offers a genuine \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e5000mAh capacity\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (approximately 18.5 watt‑hours) alongside a solid \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e15A continuous discharge\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e, giving you the freedom to run high‑power LED flashlights on turbo, keep portable fans spinning through a work shift, power camera monitors on long shoots, or energize motorized toys for hours. This cell refuses to force you into the old compromise of choosing between runtime and power.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eFlat‑Top and Unprotected — The Enthusiast’s Choice\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eDelipow intentionally supplies this cell without an external protection PCB and with a completely flush positive terminal. The flat‑top design keeps the overall length at the industry‑standard \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e70.0mm\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e, ensuring a perfect fit in the precisely machined tubes of enthusiast flashlights, the recessed bays of high‑output portable fans, and the compact battery sleds of custom electronics. Omitting the protection PCB reduces internal resistance by eliminating an extra layer of circuitry, which means more of the cell’s energy reaches your device — critical for maintaining voltage under the 10–15A loads drawn by turbo flashlights and motorized toys. Naturally, this design requires you to use a quality charger that terminates at exactly 4.2V and to install the cell only in devices that have built‑in low‑voltage cutoff. Almost every modern LED flashlight, USB‑rechargeable fan, camera accessory, and electronic toy already incorporates this essential safety feature.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eWhere 5000mAh and 15A Shine Together\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eIn a single‑LED or multi‑emitter flashlight, the 15A continuous output easily feeds turbo modes up to 4000 lumens without premature step‑down, while the 5000mAh capacity provides \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eover 5 hours of 300‑lumen medium light\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e or a full night on low. A USB desk fan running on low speed will hum for \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e10–12 hours\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e, and even on high speed, the stable voltage keeps airflow strong. For camera monitors and video lights drawing a steady 1–3A, this cell reduces the need for mid‑shoot battery swaps, letting you focus on the creative work. Motorized toys and ride‑on vehicles also see dramatic runtime improvements compared to standard 2000–3000mAh packs. And for DIY enthusiasts, the flat‑top terminal is ready for spot welding into 2S or 3S packs for power banks, portable speakers, or backup power stations.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eLong‑Life NMC Chemistry and Safety\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eThe cell’s Nickel‑Manganese‑Cobalt (NMC) formulation delivers a stable 3.6V nominal voltage and a flat discharge curve, ensuring your flashlight beam doesn’t fade and your fan speed doesn’t droop until the battery is nearly empty. With an internal resistance of \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e≤25mΩ\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e, voltage sag at 15A is a minimal 0.375V. The cell is rated for over \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e500 full charge\/discharge cycles\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e with at least 70% capacity retention, and its low self‑discharge rate allows storage for months at 3.6–3.7V. Built‑in passive safety features — a \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003ePTC thermistor\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e, a \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eresealable safety vent\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e, and a \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eCID (Current Interrupt Device)\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e — provide multiple layers of protection against over‑current, over‑pressure, and short circuits.\u003c\/span\u003e\u003c\/p\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=\"\"\u003e5000mAh High Capacity + 15A Continuous Discharge\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eDelivers extended runtime and strong current capability. Provides 5+ hours of flashlight medium light, 10–12 hours of fan operation, or weeks of standby for sensors — all while powering devices that demand up to 15A.\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 Flat‑Top Design\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eStandard 70mm length fits all 21700‑compatible devices. The flush positive terminal is essential for tight battery tubes, pogo‑pin contacts, and spot‑welded packs. Eliminates added resistance for cooler, more efficient power delivery.\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\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eMaintains a consistent 3.6V nominal voltage from 4.2V down to 2.5V with a flat discharge curve. Your light output and motor speeds stay predictable throughout the entire cycle.\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 (≤25mΩ)\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eVoltage drop at 15A is only ~0.375V. Minimal energy is wasted as heat, and your devices stay in regulation longer.\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 over 500 times with minimal capacity fade. Holds a charge for months when stored at ~3.6–3.7V — always ready for the next adventure.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eMulti‑Layered Passive Safety\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eBuilt‑in PTC thermistor, resealable vent, and CID protect against over‑current, over‑pressure, and internal short circuits.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eRugged Nickel‑Plated Steel Can\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eCorrosion‑resistant and impact‑resistant. Engineered to withstand the bumps, vibrations, and daily wear of portable electronics, fans, cameras, and outdoor use.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\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\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 Model\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eDelipow 21700 5000mAh 15A\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eBattery Type\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e21700 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\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e5000mAh (18.5Wh at 3.6V)\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=\"\"\u003e3.6V (also commonly labeled 3.7V)\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=\"\"\u003e2.5A (0.5C)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eMax Charge Current\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e5.0A (1C)\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\n\u003cstrong\u003e\u003cspan class=\"\"\u003e15A\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (3C) — verified\u003c\/span\u003e\n\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=\"\"\u003e25A (\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≤25mΩ (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\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\n\u003cstrong\u003e\u003cspan class=\"\"\u003eFlat Top (flush)\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e — no raised nipple\u003c\/span\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eDimensions\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 21.2mm dia. × 70.0mm length\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eWeight\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 70g\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eCycle Life\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e≥500 cycles (≥70% initial capacity at 0.5C charge\/discharge)\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\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eApplications\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003col start=\"1\"\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eLED Flashlights \u0026amp; EDC Torches\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eFor turbo‑capable lights that need both extreme runtime and the ability to hold voltage on high modes. The flat‑top terminal is the standard for most enthusiast flashlight tubes.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003ePortable Fans for All‑Day Cooling\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eUSB desk fans, camping fans, and job‑site fans run 10–12 hours on low speed with this cell. The flat top fits perfectly into recessed fan battery bays.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eCamera Monitors, Video Lights \u0026amp; Accessories\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eExternal field monitors, LED panels, and camera battery adapters benefit from the massive capacity and stable 15A output. Fewer battery swaps mean uninterrupted shooting.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eMotorized Toys \u0026amp; Ride‑On Vehicles\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eUpgrade RC cars, robots, and children’s ride‑on toys with a 2S or 3S pack built from these cells. The 5000mAh capacity dramatically extends playtime.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eDIY Power Banks \u0026amp; Hobby Electronics\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eThe flat‑top cell is ready for spot welding into custom 2S or 3S packs for high‑capacity USB‑C chargers, Bluetooth speakers, and portable power stations.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eSurveillance \u0026amp; Smart Home Devices\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eWireless cameras, doorbells, and motion sensors can run for months on a single charge. Low self‑discharge ensures reliability during long idle periods.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ol\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 the 15A rating continuous or pulse?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: The cell is rated for \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e15A continuous discharge\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e. It can also pulse higher (up to 25A) for short bursts. We state the honest continuous rating so you know exactly what to expect during sustained use.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ2: Why is this battery unprotected and only available as a flat top?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Delipow designed this cell for high‑capacity applications where a protection PCB would add unwanted length and resistance, and where a button top would prevent installation in tight compartments or interfere with spot welding. The flat top is the universal standard for enthusiast flashlights, fan bays, and custom packs. It’s safe when used with a quality 4.2V charger and in devices with built‑in low‑voltage cutoff. The cell’s PTC, vent, and CID provide passive protection.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ3: Will this flat‑top cell work in a device that came with a button‑top battery?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: It depends on the device. Many high‑performance flashlights and electronic devices are designed specifically for flat‑top cells. If your device has a spring‑loaded positive contact and a physical reverse‑polarity ring, it may require a button top to make contact. Check your device manual: if it specifies “flat top” or “unprotected flat top,” this cell is the correct choice.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ4: Can I use this 21700 battery in a device designed for 18650?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: No. A 21700 cell (21mm × 70mm) is physically larger than an 18650 (18mm × 65mm). Your device must explicitly support the 21700 form factor. Never force a 21700 into an 18650 tube.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ5: How long will this battery run my portable fan?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: On low speed (drawing about 0.4–0.5A), approximately 10–12 hours. On high speed (about 1.5–2A), around 3–4 hours. The 5000mAh capacity is nearly 2.5 times a standard 2000mAh 18650, providing a dramatic runtime improvement.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ6: How should I store spare cells?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Keep them in a plastic battery case away from metal and moisture. For storage longer than one month, bring the voltage to about 3.6–3.7V (roughly 50% charge). Check every 3 months and recharge if below 3.0V. Never store fully depleted.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ7: Can I bring this battery on an airplane?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Yes. At approximately 18.5Wh, it’s well under the 100Wh IATA limit for carry‑on luggage. Insulate the terminals and carry it in your hand luggage.\u003c\/span\u003e\u003c\/p\u003e","brand":"DELIPOW","offers":[{"title":"Default Title","offer_id":51454095098102,"sku":"OAS172","price":7.28,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0819\/2753\/6886\/files\/delipow-21700-5000mAh-15A-flat-top-main_e70c55aa-a30c-4b0e-912c-f6fa3aef13bc.webp?v=1786965259","url":"https:\/\/oneandes.com\/products\/delipow-3-6-volt-21700-rechargeable-battery-5000mah-flat-top-battery-15a-large-capacity-batteries-for-led-flashlight-headlamps-etc","provider":"OneAndes","version":"1.0","type":"link"}