21700 Batteries

106 products

📖 Click to view full specifications, comparison & safety guide

21700 Batteries – The Next-Gen Cylindrical Standard: Higher Capacity, Greater Power, Longer Life

Welcome to our 21700 Batteries collection. The 21700 lithium-ion cell (21mm diameter × 70mm length) is widely recognized as the most significant cylindrical battery upgrade following the 18650. Compared to 18650, the 21700 delivers nearly 50% more energy density with only a ~47% increase in volume, offering capacities from 3000mAh up to 5800mAh, lower internal resistance, and superior thermal management. This format has seen rapid adoption in Tesla EVs, premium power tools, high-power vaping devices, portable power stations, and industrial equipment.

This collection is organized into three core categories based on chemistry and safety configuration. Whether you need maximum energy density, ultimate safety, or protected plug-and-play cells, you'll find precisely what you need here.

Core Advantages of 21700 Batteries

Leap in Energy Density: Typical capacities range from 4000mAh to 5000mAh, with flagship models reaching 5800mAh—delivering extended runtime from a single cell.
Impressive Power Delivery: High-drain 21700 cells support 30A–45A continuous discharge with internal resistance as low as 8mΩ–15mΩ, ideal for power tools, vaping, and light EVs.
Superior Thermal Management: Larger surface area and internal volume improve heat dissipation, reducing temperature rise under heavy loads and enhancing system-level safety.
Extended Cycle Life: Under equivalent operating conditions, 21700 cells generally outlast 18650s, offering a lower total cost of ownership.
Growing Standardization: As an emerging mainstream format, 21700 enjoys broad support from charger, flashlight, battery holder, and device manufacturers.

21700 Battery Category Guide

Category	Positioning	Typical Capacity / Current	Best For
NMC 21700	High energy / high power NMC chemistry	4000mAh–5800mAh / 10A–45A	Flashlights, power banks, power tools, vaping, EVs
Protected 21700	Built-in overcharge/discharge/short protection	4000mAh–5000mAh / 5A–10A	High-power flashlights, headlamps, outdoor lighting, DIY power banks
IFR21700 / LiFePO₄ \| 3.2V	Inherently safe, ultra-long cycle life	1800mAh–3000mAh / 3A–10A	Solar storage, medical devices, UPS, emergency lighting, 12V replacements

Popular 21700 Cell Models – Quick Reference

Model	Brand	Nominal Capacity	Continuous Discharge	Positioning
INR21700-50E	Samsung	5000mAh	10A	High-capacity benchmark; ideal for flashlights & energy storage
INR21700-50S	Samsung	5000mAh	25A	Balanced high capacity & high drain; all-round performer
INR21700-40T	Samsung	4000mAh	35A	High drain; power tools & vaping
INR21700-30T	Samsung	3000mAh	35A–40A	Ultra-high drain; competitive vaping & racing
Molicel P42A	Molicel	4200mAh	45A	Extreme high-drain benchmark; professional power tools
Molicel P45B	Molicel	4500mAh	45A	Upgraded P42A with higher capacity
Molicel P50B	Molicel	5000mAh	25A	High capacity with solid drain capability
Panasonic NCR21700A	Panasonic	4800mAh	10A	High reliability; industrial & medical devices
LG M50LT	LG	5000mAh	10A	High capacity; EVs & energy storage
EVE 21700-50E	EVE	5000mAh	10A	Cost-effective high-capacity alternative
BAK N21700CG-50	BAK	5000mAh	15A	Balanced performance; power tools & e-bikes

Typical Specifications Range (21700)

Parameter	Typical Range
Nominal Voltage	3.2V (LiFePO₄) / 3.6V–3.7V (NMC)
Full Charge Voltage	3.65V (LiFePO₄) / 4.2V (NMC)
Capacity Range	1800mAh – 5800mAh
Continuous Discharge Current	3A – 45A (model dependent)
Internal Resistance	8mΩ – 35mΩ
Cycle Life	500 – 4000+ cycles
Operating Temperature	Charge: 0°C~45°C / Discharge: -20°C~60°C
Dimensions	Diameter 21.0mm–21.5mm × Length 70.0mm–75.0mm (protected)

Typical Applications

Application	Recommended Category	Why 21700
High-lumen flashlights / searchlights	NMC 21700 / Protected 21700	Extended runtime from a single cell
Power tools (drills, saws, grinders)	NMC 21700 (High Drain)	High torque under load with less voltage sag
Vaping / high-wattage mods	NMC 21700 (30A–45A)	Low IR, consistent power delivery
Portable power stations	NMC 21700 / IFR21700	High pack efficiency, fewer cells needed
E-bike / e-scooter packs	NMC 21700 (High Capacity)	Superior energy density reduces pack weight
Solar street lights / off-grid storage	IFR21700 / LiFePO₄	5000+ cycles, maintenance-free
Medical devices / patient monitors	IFR21700 / Protected 21700	Ultimate safety and voltage stability
Industrial sensors / remote monitoring	IFR21700	Low self-discharge, wide temperature range

How to Choose the Right 21700 Battery?

Your Requirement	Recommended Category
I need maximum capacity for longest runtime	→ NMC 21700 (High Capacity)
I need high current output for vaping or power tools	→ NMC 21700 (High Drain)
I want built-in protection for worry-free use	→ Protected 21700
Safety is critical; for solar or medical applications	→ IFR21700 / LiFePO₄ \| 3.2V
I need bulk quantities or custom battery packs	Contact our sales team for a quote

⚠️ 21700 Battery Safety Guidelines

Voltage Platform Awareness: 3.2V LiFePO₄ and 3.7V NMC cells cannot be mixed or charged with the same charger. Always verify device and charger compatibility.
Dimensional Compatibility: Protected 21700 cells are 3–5mm longer. Measure your device's battery compartment before purchase.
Use a Quality Charger: Always use a reliable charger designed for Li-ion or LiFePO₄ chemistry.
Avoid Short Circuits & Overheating: Do not short the terminals. Keep away from heat, moisture, and metal objects.
Discontinue if Damaged: Stop using cells with torn wraps, dents, or leakage. Recycle responsibly.

Why Choose Our 21700 Batteries?

Genuine Grade-A Cells: Direct sourcing from Samsung, LG, Murata, Molicel, Panasonic, EVE, BAK, and other Tier-1 manufacturers. No recycled or counterfeit cells.
Fully Tested & Matched: Every batch undergoes capacity grading, IR testing, and voltage sorting. Industrial-grade matching available.
Complete Portfolio: Covers NMC high-capacity/high-drain, protected, and LiFePO₄ series—one-stop for all 21700 needs.
Bulk & Custom Solutions: Single-cell retail, multi-pack discounts, tiered bulk pricing, and custom series/parallel pack assembly.
Certified & Documented: UN38.3, MSDS, CE, RoHS documentation provided for seamless international shipping.
Expert Technical Support: Guidance on cell selection, pack design, BMS integration, and after-sales service.

👇👇👇 Explore our NMC 21700, Protected 21700, and IFR21700 / LiFePO₄ | 3.2V collections using the subcategory navigation below. For volume quotes or custom pack solutions, please contact our engineering team.

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