{"product_id":"samsung-40t-21700-battery-4000mah-35a-9c-high-drain-li-ion-cell-flat-top-button-top-or-pre-welded-nickel-strip-for-flashlights-power-tools-drones","title":"Samsung INR21700-40T 4000mAh 3.7V 21700 Battery – 35A Continuous High Drain for Flashlights, Power Tools \u0026 Drones (Flat Top, Button Top, Nickel Tab)","description":"\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eUncompromising Power for the Most Demanding Devices\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eWhen your gear demands extreme current — a turbo flashlight blasting thousands of lumens, a cordless drill biting into steel, or a racing drone pulling full throttle — the Samsung INR21700-40T answers without hesitation. This cell is a true high‑drain champion, rated for a massive \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e35A continuous discharge\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (with pulse capability significantly higher). It packs \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e4000mAh of genuine capacity\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e, striking a deliberate balance between raw power and usable runtime. In the world of 21700 batteries, the 40T is a legend: trusted by flashlight hot‑rodders, power tool rebuilders, and FPV pilots who can't afford voltage sag at critical moments.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e35 Amps of Relentless Current\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eThe 40T's headline specification is its extraordinary ability to deliver current. With an internal resistance so low (≤14mΩ) that it barely registers heat at 35A, this cell keeps your devices at full throttle long after ordinary energy cells have collapsed in voltage. In a FET‑driven turbo flashlight drawing 20–30A, the 40T maintains a stable voltage plateau — no premature step‑down, no flickering, just a blinding wall of light. In a cordless impact driver or circular saw, the cell provides the instantaneous torque required to drive screws into hardwood or cut through sheet metal without stalling. And in a racing drone or high‑power RC model, the 40T feeds the brushless motors with the sustained current they crave, keeping lap times low and punch‑outs explosive.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eGenuine 4000mAh — Runtime That Respects the Amps\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eHigh‑drain cells often sacrifice capacity for current. Samsung has engineered the 40T to deliver both. The \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e4000mAh capacity\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (approximately 14.8 watt‑hours) means you aren't swapping batteries every few minutes. A turbo flashlight gets meaningful bursts of full brightness; a cordless tool completes a series of demanding tasks on one pack; a drone stays in the air for a competitive flight time. This is the cell you choose when you refuse to accept the false choice between power and endurance.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eUnprotected, Purpose‑Built for Enthusiasts\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eThe 40T is supplied as a bare, unprotected cell — exactly as Samsung intends. There is no external protection PCB to add length, increase resistance, or inadvertently trip under high current surges. The result is a cell that measures just 70.0mm (flat top) or 71.0mm (button top), fits effortlessly into the tightest flashlight tubes and the most compact tool battery shells, and delivers its full 35A without interference. In return, you simply use a quality charger that terminates at 4.2V and install the cell only in devices that have their own low‑voltage cutoff — a feature already present in virtually all modern turbo flashlights, brushless power tools, and drone electronics.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eThree Terminal Options for Total Flexibility\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eWe offer the 40T in three distinct positive‑terminal configurations to ensure a perfect fit for any application:\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eFlat Top:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e A completely flush positive terminal. Mandatory for ultra‑tight flashlight tubes, pogo‑pin contacts, and spot‑welded battery packs. Most enthusiast lights (ZebraLight, Noctigon, Emisar, etc.) and many power tool rebuilds require flat‑top cells.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eButton Top:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e A raised positive nipple (~1.5mm) that locks securely into spring‑loaded compartments and passes mechanical reverse‑polarity guards. Ideal for consumer flashlights, some tool adapters, and devices with spring‑based contacts.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eNickel Tab:\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e Both positive and negative ends come pre‑welded with pure nickel strips, ready for soldering or additional spot welding. The turn‑key solution for building high‑current battery packs for drones, power tools, or custom electronics.\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=\"\"\u003eSamsung INR Chemistry — The Heart of the 40T\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eUnder the nickel‑plated steel can, Samsung's advanced INR (Nickel‑Manganese‑Cobalt) chemistry delivers not only exceptional power density but also excellent thermal stability and cycle life. 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 while retaining ≥70% of its initial capacity. Low self‑discharge ensures that your spare packs stay ready for weeks or months. Built‑in safety features — a \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003ePTC thermistor\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e that increases resistance during over‑current, a \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eresealable safety vent\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e that releases pressure in extreme conditions, and a \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eCID (Current Interrupt Device)\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e that physically disconnects the electrode if internal pressure continues to rise — provide multi‑layered passive protection, giving you confidence even under the most demanding loads.\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=\"\"\u003e35A Continuous High Discharge — True 9C Rating\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eDelivers a genuine 35A continuous current. Handles the most demanding flashlights, power tools, and drones without voltage sag. Can pulse even higher for split‑second torque bursts.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e4000mAh Genuine Capacity (14.8Wh)\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA balanced capacity that provides meaningful runtime in high‑drain applications. Enough for sustained turbo bursts, repeated tool tasks, or competitive drone flights.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eUltra‑Low Internal Resistance (≤14mΩ)\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eMinimal heat generation and voltage drop. At 35A, the voltage sags by only ~0.49V, keeping your devices in regulation and your performance at its peak.\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 Bare Cell — Standard 70mm Length\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eFits all 21700‑compatible devices. Eliminates the added resistance and length of a protection PCB, essential for high‑current applications. Requires a quality 4.2V Li‑ion charger and a device with low‑voltage cutoff.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eThree Terminal Options: Flat Top, Button Top \u0026amp; Nickel Tab\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eFlat Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e for ultra‑tight tubes and pogo‑pin contacts. \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eButton Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e for spring‑loaded compartments. \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eNickel Tab\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e for ready‑to‑weld high‑current battery packs. Complete versatility.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eAdvanced Samsung INR (NMC) Chemistry\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eProvides a stable 3.7V nominal voltage, flat discharge curve, and excellent thermal stability — trusted in professional power tools and electric vehicles.\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 charge for months when stored at 3.6–3.7V — always ready for the next race, job, or 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 safety 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. Built to withstand the vibrations, drops, and temperature swings of power tools, drones, and outdoor environments.\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\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=\"\"\u003eSamsung INR21700-40T\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=\"\"\u003e4000mAh (14.8Wh)\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=\"\"\u003e2.0A (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=\"\"\u003e4.0A (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=\"\"\u003e35A\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (approx. 9C) — verified high‑drain\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=\"\"\u003e45A (\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≤14mΩ (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=\"\"\u003eFlat Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (flush) \/ \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eButton Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (raised ~1.5mm) \/ \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eNickel Tab\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e (pre‑welded nickel strips)\u003c\/span\u003e\n\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. 21.1mm dia. × 70.0mm length\u003c\/span\u003e\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. 21.1mm dia. × 71.0mm length\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eDimensions (Nickel Tab)\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 21.1mm dia. × 70.0mm + nickel strip protrusions\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eWeight (Flat Top)\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 68g\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eWeight (Button Top)\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 69g\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eWeight (Nickel Tab)\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eApprox. 69g (including nickel strips)\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 75°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=\"\"\u003eINR (Lithium Nickel Manganese Cobalt Oxide — NMC)\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. Turbo Flashlights \u0026amp; Hot‑Rod Lights\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eFor FET‑driven multi‑emitter flashlights, custom SBT90.2 builds, and any light that pulls 20–35A, the 40T is the gold standard. It holds voltage rock‑steady, preventing early step‑down and keeping lumens at maximum. Flat top fits ultra‑tight enthusiast tubes; button top secures in spring‑loaded hosts.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e2. Cordless Power Tools (Rebuilds \u0026amp; Upgrades)\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eReplace worn‑out cells in drills, impact drivers, circular saws, and angle grinders with 40T cells. The 35A continuous discharge handles the startup spikes and sustained loads of professional‑grade tools. Use flat tops or nickel tabs to build 5S1P or 5S2P packs for 18V\/20V platforms.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e3. Racing Drones \u0026amp; FPV Quadcopters\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eThe 40T is a favorite among drone pilots who need high current and low voltage sag for punch‑outs and high‑speed runs. Build a 4S or 6S pack for racing or freestyle quads; the 4000mAh capacity provides competitive flight times while delivering the amps that brushless motors demand.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e4. High‑Power RC Models\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eRC cars, trucks, boats, and aircraft that run on 2S–6S Li‑ion packs benefit from the 40T's blend of current and capacity. Whether you're bashing, crawling, or speed‑running, the 40T delivers the punch and runtime you need.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e5. E‑Bike \u0026amp; Scooter Battery Packs\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eFor high‑power e‑bikes and scooters that require sustained high current, the 40T is an excellent cell choice in multi‑parallel configurations (e.g., 4P, 5P). It provides the necessary current without the excessive voltage sag of lower‑drain cells.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003e6. Portable High‑Power Inverters \u0026amp; Power Stations\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eDIY battery packs for portable inverters, camping power stations, and job‑site generators often demand high surge currents. The 40T handles these with ease, providing reliable power for tools, lights, and electronics.\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 the Samsung 40T really capable of 35A continuous?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Yes. Samsung rates the INR21700-40T for 35A continuous discharge. With an internal resistance of only ~14mΩ, it can sustain this current while staying within safe temperature limits. It can also pulse higher (up to 45A) for short bursts.\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 to use in a flashlight or power tool?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Samsung 40T cells are designed as bare cells for pack building and high‑drain applications. Omitting the protection PCB minimizes length, reduces resistance, and prevents the current limit from tripping during high surges. It is completely safe when you use a quality 4.2V Li‑ion charger and only install it in devices that have built‑in low‑voltage cutoff — a standard feature in modern turbo flashlights, brushless tools, and drone electronics. The cell includes PTC, vent, and CID for passive safety.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ3: Which terminal option should I choose — Flat Top, Button Top, or Nickel Tab?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eFlat Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e for ultra‑tight flashlight tubes and pogo‑pin contacts, and for spot‑welded packs. \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eButton Top\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e for spring‑loaded compartments and devices with reverse‑polarity rings. \u003c\/span\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eNickel Tab\u003c\/span\u003e\u003c\/strong\u003e\u003cspan class=\"\"\u003e if you are soldering or spot‑welding the cell into a pack. Consult your device manual if unsure.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ4: Can I use the 40T in a device designed for an 18650?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: No. A 21700 cell (21mm × 70mm) is larger than an 18650 (18mm × 65mm). The device must explicitly support 21700 batteries. 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 does the 40T compare to the Samsung 50E or 30T?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: The 40T sits between the 50E (5000mAh, 10A) and the 30T (3000mAh, 35A but with higher pulse capability). The 40T offers a balanced 4000mAh capacity with 35A continuous — ideal for users who need both high current and decent runtime. The 30T is better for absolute maximum pulse current; the 50E is better for maximum runtime at lower currents.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ6: How hot does the 40T get at 35A?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: With ≤14mΩ internal resistance, heat generation at 35A is relatively modest. The cell will become warm — typically reaching ~60–70°C under sustained 35A load after several minutes — but remains within safe operating limits. Allow the cell to cool between heavy discharge cycles when possible.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ7: Can I charge the 40T at 4A?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Yes, the maximum charge current is 4A (1C). However, for maximum cycle life, we recommend the standard 2A (0.5C) charge rate. Faster charging generates more heat and may slightly reduce long‑term capacity retention.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eQ8: How should I store spare 40T cells?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Store them in a plastic battery case or silicone sleeve, away from metal objects 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 the voltage drops 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=\"\"\u003eQ9: Can I bring the 40T on an airplane?\u003c\/span\u003e\u003c\/strong\u003e \u003cbr\u003e\u003cspan class=\"\"\u003eA: Yes. At 14.8Wh, it is well under the 100Wh IATA limit for carry‑on luggage. Insulate the terminals with tape or a plastic case and carry the cells in your hand luggage.\u003c\/span\u003e\u003c\/p\u003e","brand":"Samsung","offers":[{"title":"Button Top","offer_id":51454092935414,"sku":"OAS164","price":6.98,"currency_code":"USD","in_stock":true},{"title":"Flat Top","offer_id":51454092968182,"sku":"OAS165","price":6.98,"currency_code":"USD","in_stock":true},{"title":"Nickel Tab","offer_id":51454093000950,"sku":"OAS166","price":6.98,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0819\/2753\/6886\/files\/samsung-21700-4000mAh-tip-battery-main_058eb1b3-7c3d-466c-b337-b87e49861992.webp?v=1786965253","url":"https:\/\/oneandes.com\/products\/samsung-40t-21700-battery-4000mah-35a-9c-high-drain-li-ion-cell-flat-top-button-top-or-pre-welded-nickel-strip-for-flashlights-power-tools-drones","provider":"OneAndes","version":"1.0","type":"link"}