Long Life 21700 Batteries for Renewable Energy and Backup Power Systems
Product Overview
XTAR 21700 USB-C Li-ion battery delivers 5000mAh capacity with 10A discharge capability. Features USB-C direct charging (4.6 hours full charge, 3 hours via XTAR VX4 charger). Standard 21700 size with 800+ cycle life, operating range of -20°C to 60°C, multiple protection features, and balanced cell design. Ideal for flashlights, bike lights, weather stations, and various outdoor/EDC applications.
Key Features
- Supports 5V 2.5A fast charging
- Smart 3-stage charging algorithm for extended battery life
- 0V activation to recover over-discharged batteries
- Self-managed power solution
Technical Specifications
| Model |
21700 USB-C Li-ion Battery |
| Capacity |
5000mAh |
| Voltage |
3.6V |
| Max Discharge Current |
10A |
| Charging Voltage |
4.2±0.03V |
| Charging Current |
2500mA |
| Operating Temp. |
-20-60°C |
| Storage Temp. |
-20-55°C (Best at 25±5°C) |
| Cycle Life |
800+ |
| Protected |
Yes |
| Positive Terminal |
Flat Top |
| Dimensions(mm) |
φ21.5±0.3 x H75.5±0.5 |
| Net Weight(g) |
73 |
Applications
![XTAR battery applications including flashlights, bike lights, and outdoor equipment]()
About XTAR
Established in 2006, XTAR is a leading provider of high-quality lithium-ion batteries, smart chargers, and LED flashlights. Based in Shenzhen, we integrate R&D, production, and sales to deliver innovative power solutions. With over 20 years of expertise, XTAR is your trusted partner for reliable energy products, offering customized solutions for OEM and wholesale clients.
Company Timeline
2005
Developed PK keychain flashlight with superior batteries and LEDs for brighter output and longer runtime
2006
Introduced industry's first 16340 and 18650 lithium-ion batteries with protection circuits
2009
Pioneered three-stage charging technology for lithium batteries (Patent No.: 201720828840.6)
2011
Launched WP2II charger with 0V activation & USB output
2013
Released PANZER XP4, first charger intelligently adapting to lithium-ion and nickel-metal hydride batteries
2017
Launched Over 4 Slim, market's first 4.1A*2 fast charger with internal resistance/temperature detection
2020
Launched next-gen 1.5V rechargeable AA lithium batteries
2024
Expanded 1.5V AA/AAA lithium battery line with Constant Voltage + Linear series
2025
Joined U.S. ATA & SHOT Show; launched world-first touch battery power check technology
Manufacturing Capabilities
We operate our own factory with efficient production processes ensuring precise production cycles. Manufacturing under our original brand guarantees product consistency and provides convenient maintenance and after-sales service. XTAR integrates the brand values of safety, reliability, and innovation into every product.
![XTAR manufacturing facility and production processes]()
Global Partners
![XTAR global partners and distribution network]()
Global Certifications
ISO-9001 Certification
MSDS Certification
UN38.3 Certification
CE Certification
RoHS Certification
![XTAR product certification documents and compliance badges]()
Frequently Asked Questions
Can I have a sample order for Battery/Charger?
Yes, we welcome sample orders to test and check quality. Mixed samples are acceptable.
What about the lead time?
Sample needs 1-2 days, mass production time needs 3-7 working days.
How do you ship the goods and how long does it take to arrive?
DHL, UPS, FedEx or TNT and others shipping method is available. Arriving time depends on the way you choose. Airline and sea shipping also optional. Warehouse in Texas, shipment is free in US.
Is it OK to print my logo on the product?
Yes. We have our own R&D Department and Factory. Both OEM and ODM are acceptable.
What industries do you provide supporting equipment for?
We can provide professional supporting services for many industries, such as electric toothbrushes, thermal imagers, infrared devices, thermal imaging scope, flashlights, toy cars, smart locks, and more.
Where do you ship from?
We can ship from Shenzhen, China, and we also have overseas warehouses in the U.S., so we can also ship directly from the U.S.
