Key Features
- High-Capacity 21700 Cell: 4000mAh lithium-ion battery for professional applications.
- High Output Performance: 20A continuous with 30A pulse discharge capability.
- Flat Top Terminal: Optimized for integrated battery pack designs.
- Unprotected Cell Design: Requires system-level battery management.
- Efficient Power-to-Weight: Strong output with manageable weight.
Overview
The MXJO 21700 4000mAh Battery is engineered for commercial and professional power systems that demand high energy density and consistent output. Its flat-top 21700 design supports modern battery pack configurations, while the unprotected construction allows for seamless integration into managed power systems. Proper protection circuitry is required for safe operation.
Applications / Uses
- OEM battery pack manufacturing
- Commercial electronic equipment
- High-capacity energy storage systems
- Laboratory and R&D environments
- Specialized portable power solutions
SPECIFICATIONS
| Manufacturer: | MXJO |
| Size: | 21700 |
| Positive Terminal: | Flat Top |
| Nominal Capacity: | 4000mAh |
| Continuous Discharge Rating (max): | 20A Maximum Continuous / 30A Maximum Pulse |
| Nominal Voltage: | 3.7V |
| Maximum Voltage: | 4.2V |
| Protected: | No (Unprotected) |
| Rechargeable: | Yes |
| Approx. Dimensions: | 21.7mm x 71mm |
| Approx. Weight: | 69g (Max) |
⚠ Important Safety Warnings
Improper handling or misuse of this lithium-ion battery can result in FIRE, EXPLOSION, or THERMAL RUNAWAY, causing personal injury, property damage, or death. Users must read and follow all safety guidelines before purchase and use. Click here to review the full safety guidelines.
- Critical Warning: Never carry loose batteries in your pocket, purse, or bag. Loose batteries can come into contact with metal objects like keys or coins, causing a short circuit, which may result in severe burns, fire, or explosion. Always store or transport batteries in a protective case.
- Intended Use: This battery is designed for integration into protected battery packs with a Battery Management System (BMS) or Protection Circuit Board (PCB). It is not intended for standalone use or for e-cigarettes, vaporizers, or similar devices.
-
Thermal Runaway: A chain reaction where heat from a failing battery
causes further overheating, potentially leading to fire or explosion.
- Causes: Overcharging, short circuits, physical damage, or exposure to high temperatures.
- Prevention: Use a smart charger, avoid damage, and store batteries in a cool, dry place.
- Storage & Transport: Always store batteries in protective cases to prevent accidental contact with metal objects. Never store loose batteries in pockets, purses, bags, or near conductive materials.
- Inspection: Do not use if the PVC wrapper, terminal insulator, or casing is damaged, dented, leaking, or bulging. Continued use could result in failure, fire, or explosion.
- Charging: Use a smart charger specifically designed for lithium-ion batteries and ensure the charger's voltage matches the battery's specifications. Never overcharge, over-discharge, or leave unattended while charging.
-
Prohibited Activities:
- Do not expose the battery to extreme heat, fire, or liquids.
- Do not short circuit, puncture, crush, or modify the battery.
- Do not charge or discharge beyond the manufacturer’s voltage range.
- Do not dispose of in regular trash—always recycle at approved facilities.
- Emergency Response: If a cell shows signs of thermal runaway (e.g., smoke, swelling, hissing, or heat), stop use immediately and, if it can be done safely, move it to a non-flammable surface (e.g., concrete or sand) away from combustible materials. Lithium-ion cells burn as Class B fires — use an ABC / dry-chemical fire extinguisher, or douse with large amounts of water to cool the cell and prevent the fire from spreading. Do not rely on a small spray; thorough cooling is required, and cells can reignite from residual heat, so monitor the area afterward. (Class D extinguishers are intended for lithium-metal batteries, not lithium-ion.) For any fire beyond a single small cell, evacuate and call emergency services.
Disclaimer
18650Battery.com is not responsible for any damages, injuries, or claims arising from improper use, handling, or failure to follow these safety guidelines. Lithium-ion batteries require strict adherence to all safety protocols. It is the reseller's responsibility to ensure all safety warnings and product guidelines are effectively communicated to customers. Users and resellers assume full responsibility for the safe handling, usage, and distribution of this product.