The ASOL21700 is a premium-grade 21700 cylindrical Li-ion battery cell delivering 3.7V nominal voltage and an impressive 5000mAh capacity (18.5Wh). The 21700 format (21mm diameter × 70mm length) offers approximately 35% higher energy density than traditional 18650 cells — making it the preferred choice for manufacturers building high-performance flashlights, power banks, cordless tools, and electric mobility devices that demand longer runtime and greater power output.
Engineered with advanced NCM (Nickel-Cobalt-Manganese) cathode chemistry, the ASOL21700 delivers stable discharge curves, low internal resistance, and excellent high-rate performance up to 3C (15A) continuous discharge. Each cell undergoes rigorous formation cycling, capacity grading, and internal resistance matching — ensuring consistent quality for battery pack assembly and OEM production.
Backed by ASOLENERGY TECHNOLOGY’s ISO-certified production facility, every ASOL21700 cell is produced under strict quality control with full traceability. Whether you are a flashlight brand sourcing reliable cells, a power tool manufacturer upgrading from 18650 to 21700, or an e-bike pack assembler needing matched cell sets — the ASOL21700 delivers the performance, consistency, and value your production line demands.
Technical Specifications
| Parameter | Value |
|---|---|
| Chemistry | Li-ion (NCM 21700 cylindrical cell) |
| Model | ASOL21700 |
| Nominal Voltage | 3.7V |
| Capacity | 5000mAh (typical) |
| Energy | 18.5Wh |
| Charging Voltage | 4.2V (CC/CV) |
| Standard Discharge Current | 0.2C (1000mA) |
| Max Continuous Discharge | 3C (15A) |
| Cycle Life | ≥500 cycles @ 80% capacity retention (0.5C, 25°C) |
| Operating Temperature | −20°C to +60°C (charge: 0°C to +45°C) |
| Dimensions | 21.0mm (D) × 70.0mm (L) ± 0.3mm |
| Weight | Approx. 68g |
| Internal Resistance | ≤25 mΩ (fresh cell) |
| Certifications | CE, RoHS, UN38.3, MSDS (UL / IEC 62133 available for bulk) |
| Manufacturer | ASOLENERGY TECHNOLOGY |
Application Scenarios
1. Tactical Flashlight & Lighting
The 21700 format is now the industry standard for high-lumen tactical and EDC flashlights. Higher capacity and discharge rate deliver significantly longer runtime at maximum output compared to 18650 cells.
- Tactical Flashlights
- High-Lumen LED Flashlights
- Search & Rescue Lights
- Hunting Lights
- EDC Flashlights
- Diving Lights
- Weapon-Mounted Lights
2. Outdoor Camping Light & Lantern
Extended runtime is critical for outdoor and emergency lighting. The 5000mAh capacity provides all-night illumination for camping lanterns, work lights, and portable floodlights.
- Camping Lanterns
- Tent Lights
- Rechargeable Work Lights
- Emergency Lights
- Portable LED Floodlights
- Night Fishing Lights
3. Portable Power Bank & Energy Storage
With 18.5Wh per cell, the ASOL21700 is an excellent building block for high-capacity power banks, solar-charged storage units, and DIY battery pack projects.
- High-Capacity Power Banks
- USB-C PD Power Banks
- Solar Power Banks
- DIY Battery Packs
- Portable Energy Storage
4. Cordless Power Tools
Power tool manufacturers are rapidly transitioning to 21700 for higher torque and longer runtime. The 15A discharge capability handles peak loads from drills, grinders, and impact drivers.
- Cordless Drills
- Impact Drivers
- Cordless Grinders
- Garden Tools
- Professional Power Tools
5. Electric Bicycle / E-Mobility
21700 cells are widely adopted in e-bike and scooter battery packs. The higher energy density means lighter packs with equivalent or greater range compared to 18650-based systems.
- E-Bike Battery Packs
- Electric Scooters
- E-Mopeds
- Light EV Battery Modules
- Shared Mobility Vehicles
6. Cordless Devices & DIY Projects
The ASOL21700 is ideal for consumer electronics manufacturers and hobbyists building custom battery assemblies for fans, vacuums, RC models, and other portable devices.
- Cordless Fans
- Portable Vacuums
- DIY Battery Projects
- Custom Battery Assemblies
- Hobby Electronics
Why Choose 21700 Over 18650?
The 21700 cylindrical cell format is rapidly becoming the new industry standard, adopted by leading brands including Tesla, Milwaukee Tool, and SureFire:
- 35% More Energy Density — 21700 cells store significantly more energy per cell (up to 5000mAh vs. 2600–3500mAh for 18650), reducing the total cell count needed in battery packs.
- Better Thermal Management — The larger surface area dissipates heat more effectively, enabling higher sustained discharge rates without overheating.
- Lower Pack Cost — Fewer cells needed for the same total capacity means fewer welds, less BMS complexity, and reduced assembly cost.
- Higher Discharge Capability — 21700 cells typically support 2C–3C continuous discharge, suitable for power tools and high-lumen flashlights.
- Future-Proof Platform — Major OEMs have committed to the 21700 format for new product lines, ensuring long-term supply chain stability.
Why Choose ASOL?
- Factory-Direct Pricing — No distributor markups. Competitive wholesale rates directly from the manufacturer, with volume-based pricing tiers for bulk orders.
- Grade-A Cell Consistency — Every cell is graded by capacity and internal resistance. Matched cell sets (±5mΩ IR tolerance) available for professional battery pack assembly.
- High Discharge Capability — Supports up to 3C continuous discharge (15A), validated by independent testing. Ideal for high-drain applications.
- Proven Cycle Durability — Grade-A NCM cells deliver ≥500 cycles at 80% capacity retention under standard test conditions (0.5C charge/discharge, 25°C).
- Full OEM & ODM Services — Custom branded shrink wrap, pre-wired with your choice of connector (JST, Molex, XT60, etc.), PCB/PCM integration, and full battery pack assembly available.
- 100% Outgoing QC — Every cell individually tested for open-circuit voltage (OCV), internal resistance (IR), and discharge capacity before shipment. Zero-defect target.
- Free Samples Available — Sample orders of 10–50 pcs accepted for performance evaluation. Dedicated technical support during your testing phase.
Packaging & Shipping
| Item | Details |
|---|---|
| Individual Packaging | Anti-static bag + foam separator (standard cylindrical cell packaging) |
| Inner Box | 50 pcs / inner box |
| Carton | 200 pcs / carton (customizable) |
| Carton Dimensions | Approx. 38 × 28 × 22 cm (subject to final packing) |
| Carton Weight | Approx. 14–16 kg |
| Shipping Options | Express (DHL / FedEx / UPS), Air freight, Sea freight |
| Shipping Terms | EXW, FOB, CIF, DDP available |
| Dangerous Goods | UN38.3 certified — compliant for air and sea transport (Class 9) |
Frequently Asked Questions
Q: Can I order cells with pre-installed protection circuit (PCB/PCM)?
A: Yes. We can supply ASOL21700 cells with built-in PCB protection (overcharge / over-discharge / overcurrent protection) and pre-wired with your choice of connector (JST, Molex, XT60, etc.). MOQ applies for custom configurations.
Q: What is the minimum order quantity (MOQ)?
A: Standard cell orders start at 200 pcs. For custom configurations (protected cells, pre-wired, branded wrap), MOQ is 500–1000 pcs depending on complexity. Sample orders of 10–50 pcs are welcome for evaluation — contact us to arrange.
Q: Do you provide cell matching / grading for battery pack assembly?
A: Yes. We offer cell grading by capacity and internal resistance. Matched cell sets are available for pack builders who need consistent performance across series/parallel configurations. Contact us for grading specifications and tolerances.
Q: What certifications are available?
A: All standard cells ship with CE, RoHS, UN38.3, and MSDS compliance. Additional certifications (UL, IEC 62133, BIS) can be arranged for volume orders upon request.
Q: Is the ASOL21700 suitable for flashlight manufacturers?
A: Absolutely. The 21700 format is the current industry standard for high-performance tactical and EDC flashlights. With 5000mAh capacity and high-rate discharge capability, the ASOL21700 delivers the runtime and output that flashlight brands and consumers demand.
Q: What is the difference between 21700 and 18650 battery cells?
A: The 21700 format (21mm diameter × 70mm length) offers approximately 35% higher energy density than the standard 18650 (18mm × 65mm). A typical 21700 cell holds 5000mAh vs. 2600–3500mAh for 18650, delivering significantly longer runtime while maintaining similar or better discharge performance.
Contact
| info@asol-battery.com | |
| +86 157 7985 8703 | |
| Website | www.asol-battery.com |
| Response Time | Within 24 hours on working days |
Sample lead time: 3–5 business days | Bulk production: 10–20 business days
Ready to source reliable 21700 cells for your production line?
Send us your application details, target quantity, and any custom requirements — we will respond within 24 hours with a competitive factory-direct quote and free sample arrangement.
