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 quality-controlled 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 | 0°C to +60°C (charge: 0°C to +45°C) |
| Dimensions | 21.0mm (D) × 70.0mm (L) ± 0.3mm |
| Weight | Approx. 68g |
| Internal Resistance | ≥5 mΩ (fresh cell) |
| Certifications | CE, RoHS, UN38.3, MSDS |
| Manufacturer | ASOLENERGY TECHNOLOGY |
Applications
Where the 21700 is used
High-lumen EDC & search lights with long max-output runtime.
All-night outdoor, emergency & work lighting on 5000mAh.
18.5Wh per cell for high-capacity USB-C PD & solar banks.
15A discharge handles drills, grinders & impact drivers.
High energy density for lighter, longer-range e-mobility packs.
Custom packs for fans, vacuums, RC models & hobby builds.
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 ASOL
Factory-direct, fully customizable
Connector, wire gauge, heat-shrink color, custom brand label, BMS & housing.
Integrated PCB against overcharge, over-discharge, overcurrent & short circuit.
Grade-A cells, voltage-matched ±10mV for stable, reliable performance.
Custom prototype samples in 5–7 business days before volume production.
Every unit tested for OCV, capacity & protection. Defect rate <0.3%.
UN38.3 Class 9 air & sea · DHL/FedEx/UPS · EXW/FOB/CIF/DDP.
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
Can I order cells with pre-installed protection circuit (PCB/PCM)?
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.
What is the minimum order quantity (MOQ)?
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 10-20 pcs are welcome for evaluation — contact us to arrange.
Do you provide cell matching / grading for battery pack assembly?
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.
What certifications are available?
All standard cells ship with CE, RoHS, UN38.3, MSDS compliance.
Is the ASOL21700 suitable for flashlight manufacturers?
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 OEM buyers demand.
What is the difference between 21700 and 18650 battery cells?
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@asolbattery.com | |
| +86 157 7985 8703 | |
| Website | www.asolbattery.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 sample development arrangement.
Need a different size or capacity? Explore ASOL’s full cylindrical battery range →
