Delipow 4000mAh 3.6V 21700 Flat Top Battery – High Drain Max 48A for Turbo Flashlights, RC Models & Power Tools

Product Description

Uncompromising Flat‑Top Power for the Most Demanding Gear
When your equipment demands a brutal surge of current — a turbo flashlight burning at 5000 lumens, a 1/8 scale RC truggy launching off the line, or a cordless impact wrench hammering lug nuts — you need a battery that delivers without hesitation. The Delipow 4000mAh 21700 flat‑top cell is engineered for exactly these moments. It offers a staggering 48A max pulse discharge, backed by a robust 30A continuous capability, all while storing a genuine 4000mAh (approximately 14.4 watt‑hours at 3.6V nominal). This is the no‑compromise choice for enthusiasts and professionals who refuse to let voltage sag rob their performance.

Why Flat‑Top and Unprotected?
This cell is purpose‑built as a bare, unprotected, flat‑top battery. We intentionally omit the external protection PCB to keep the overall length at the industry‑standard 70.0mm — critical for fitting into the precisely machined battery tubes of high‑end flashlights, the compact shells of power tool packs, and the densely arranged sleds of RC battery trays. The flat‑top positive terminal sits completely flush with the cell body, making it the universal standard for pogo‑pin contacts, recessed flat PCB connections, and clean spot‑welding onto nickel strips. There is no raised button to interfere with tight‑fitting caps or to create uneven pressure during pack assembly. Removing the protection PCB also eliminates the extra electrical resistance that can limit current flow during high‑drain pulses, ensuring your devices get every last amp they demand. Of course, this design requires responsible use: you must pair this cell with a quality charger that terminates at exactly 4.2V, and you must only install it in devices that have built‑in low‑voltage cutoff. Virtually all modern turbo flashlights, brushless RC electronic speed controllers, and cordless tool motor controllers already incorporate this essential safety feature.

Where 48A Pulse Power Makes the Difference
In a FET‑driven turbo flashlight (such as an Emisar D4SV2, Noctigon K1, or a custom SBT90.2 hot‑rod), the Delipow cell instantly responds to the 20–35A demand of multiple high‑discharge LEDs, holding voltage rock‑steady so the beam never flickers and the thermal step‑down is dictated by heat, not electrical starvation. In a 1/8 scale RC monster truck or a 1/10 scale touring car, a 2S or 3S pack built from these flat‑top cells delivers brutal punch out of corners and relentless top‑end speed. The flat terminals weld seamlessly into stick packs, saddle packs, and drone battery configurations. For cordless power tools — high‑torque drills, impact drivers, and mini circular saws — the 30A continuous rating prevents motor stall under heavy load, while the 4000mAh capacity lets you drive dozens of screws or make multiple cuts before reaching for the charger. The flat‑top design is the standard for rebuilding 18V/20V tool battery packs, where cells are spot‑welded in series.

Advanced Chemistry, Built to Last
Delipow’s NMC (Nickel‑Manganese‑Cobalt) formulation provides a stable 3.6V nominal voltage and an impressively flat discharge curve. With an internal resistance of only ≤16mΩ, voltage sag at 30A is a mere 0.48V, meaning your devices stay in regulation and your performance remains predictable from a full charge down to the cutoff. The cell is rated for over 500 full charge/discharge cycles while retaining at least 70% of its original capacity, and its low self‑discharge rate allows you to store spares for months at the recommended 3.6–3.7V. Built‑in safety mechanisms — a PTC thermistor that increases resistance during over‑current, a resealable safety vent that releases internal pressure in extreme conditions, and a CID (Current Interrupt Device) that physically disconnects the electrode under catastrophic pressure — provide multiple layers of passive protection, ensuring safe operation even under the most extreme loads.

Key Features

• Extreme High‑Drain: 30A Continuous / 48A Max Pulse
  Feeds power‑hungry turbo flashlights, RC models, and power tools without breaking a sweat. The 30A continuous rating keeps you at full power; the 48A pulse delivers headroom for instantaneous startup surges.

• Genuine 4000mAh Capacity (14.4Wh)
  Delivers meaningful runtime in high‑current applications — roughly 10–15 minutes of continuous turbo in a flashlight, a full RC heat, or dozens of tool operations per charge.

• Unprotected Flat‑Top Design — The Enthusiast Standard
  Flush positive terminal fits the tightest battery tubes and recessed contacts. Eliminates the added length and resistance of a protection PCB. Requires a 4.2V Li‑ion charger and a device with built‑in low‑voltage cutoff.

• Ultra‑Low Internal Resistance (≤16mΩ)
  Voltage drops by only 0.48V at 30A. Minimal heat generation, maximum power delivery, and longer regulation for your devices.

• Stable NMC Chemistry & Flat Discharge
  Maintains a consistent 3.6V nominal voltage from 4.2V down to 2.5V. Your light output, motor RPM, and tool torque stay predictable throughout the entire discharge cycle.

• 500+ Cycle Life & Low Self‑Discharge
  Recharge over 500 times with minimal capacity fade. Stays ready for months in storage at ~3.6–3.7V — always prepared for your next project or power outage.

• Multi‑Layered Passive Safety
  Built‑in PTC thermistor, resealable safety vent, and CID protect against over‑current, over‑pressure, and internal short circuits.

• Rugged Nickel‑Plated Steel Can
  Corrosion‑resistant and impact‑resistant. Built to withstand the vibrations, drops, and harsh conditions of power tools, RC vehicles, and outdoor environments.

Technical Parameters

Applications

1. Turbo Flashlights & High‑Lumen Mods
For FET‑driven, multi‑emitter, or custom SBT90.2 flashlights that pull 20–35A on turbo, this flat‑top cell provides the instantaneous current for maximum brightness without early step‑down. The flush terminal is essential for the tight battery tubes found in enthusiast lights.

2. RC Cars, Trucks, Boats & Drones
Build a 2S or 3S Li‑ion pack for 1/10 or 1/8 scale vehicles. The 30A continuous output feeds brushless motors with relentless acceleration and top speed, while the flat‑top design allows clean, low‑profile spot welds for professional‑grade packs.

3. Cordless Power Tools (Rebuilds & Upgrades)
Replace worn‑out cells in drills, impact drivers, circular saws, and angle grinders. The high drain rate handles startup spikes and heavy loads, and the flat‑top terminal is the standard for welding into 5S1P or 5S2P packs for 18V/20V platforms.

4. High‑Power Portable Fans & Cooling Devices
Large portable fans that draw 3–8A on high speed run powerfully and consistently. The flat top mates seamlessly with recessed contacts in many high‑output fan battery bays.

5. DIY High‑Current Power Banks & Portable Inverters
Build a power station that can fast‑charge multiple devices or run a small AC inverter. The flat‑top cell is ready for spot welding into series/parallel configurations without button‑top interference.

6. Professional & Industrial Equipment
Portable barcode scanners, thermal printers, and medical devices that require high‑current pulses for motors or actuators and dependable runtime are well‑served by this flat‑top 4000mAh cell.

FAQ

Q1: Can this cell really handle 48A? What does "Max 48A" mean?
A: Yes. The cell is rated for 30A continuous discharge and can safely pulse up to 48A for very short bursts (under 3 seconds). We specify both figures so you know exactly what to expect. For applications that demand a sustained 48A, you may need an ultra‑high‑rate cell like the Samsung 30T. This Delipow cell excels at delivering high continuous current with the ability to handle extreme instantaneous surges.

Q2: Why is this battery unprotected and only available in flat top?
A: This cell is designed specifically for high‑drain applications. A protection PCB would add unwanted length and internal resistance, potentially limiting current during peak loads. A button top would interfere with the tight battery tubes of many enthusiast flashlights and complicate spot welding. The flat‑top design is the universal standard for high‑performance devices. It is completely safe when used with a quality 4.2V charger and in devices that have built‑in low‑voltage cutoff. The cell itself includes passive safety layers (PTC, vent, CID).

Q3: Will this flat‑top cell work in a flashlight that originally used a button‑top battery?
A: It depends. Many high‑performance and enthusiast flashlights are designed for flat‑top cells because they offer lower resistance and a more compact fit. If your light has a spring‑loaded positive contact and a physical reverse‑polarity ring, a button top might be required to bridge the gap. Check your device manual: if it specifies "flat top" or "unprotected flat top," this cell will work perfectly. If not, you may need a button‑top cell.

Q4: Can I use this 21700 cell in a device that takes 18650 batteries?
A: No. A 21700 cell (21mm diameter, 70mm length) is physically larger than an 18650 (18mm × 65mm). Your device must explicitly support the 21700 form factor. Forcing a 21700 into an 18650 tube can damage both the cell and the device.

Q5: How hot does this battery get at 30A continuous?
A: With an ultra‑low internal resistance of ≤16mΩ, heat generation is relatively modest. The cell will become warm — typically reaching around 60–70°C after several minutes of sustained 30A — but remains within safe operating limits. Allow the cell to cool between heavy discharge cycles for best longevity.

Q6: Can I charge this battery at 4A?
A: Yes, 4A (1C) is the maximum charge current. However, for optimal cycle life, we recommend the standard 2A (0.5C) charge rate. Fast charging generates more heat and may slightly accelerate long‑term capacity fade.

Q7: How should I store spare cells?
A: Keep 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.

Q8: Can I bring this battery on an airplane?
A: Yes. At approximately 14.4Wh, 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.