FlexCharge 21700 DIY Detachable Fast Charge Power Bank

The last power bank you’ll ever need—customizable, sustainable, and powerful.

Take control of your energy with the FlexCharge. Designed for the tech enthusiast and the eco-conscious traveler, this 2026 edition DIY kit features a revolutionary detachable design that allows you to swap out 21700 batteries in seconds. Whether you need high-speed 22.5W power for your smartphone or a specialized low-current mode for your earbuds, the FlexCharge adapts to your specific needs while ensuring you never have to throw away a power bank again just because the internal cells died.

Product Highlights

• Infinite Battery Life: Featuring a one-touch ejection system, you can instantly swap flat-top 21700 lithium batteries to keep your power endless.

• 22.5W Intelligent Fast Charging: Supports high-speed Type-C input and output (up to 4.5A) to rapidly fuel your flagship devices and the power bank itself.

• Exclusive Dual-Mode Tech: Switch between high-power output for phones and an optimized Low-Current Mode specifically designed to safely charge smartwatches and Bluetooth headsets.

• Innovative Lanyard Cable: Includes a premium dual-head fast-charging cable that doubles as a durable carrying lanyard, ensuring you’re always prepared.

• Precision Data Monitoring: Integrated digital interface provides real-time data recording of your charging status and battery health.

• Sustainable DIY Design: Minimize electronic waste. By using replaceable cells, you maintain a high-performance charger that evolves with your battery upgrades.

• Compact & Flight-Ready: A sleek, pocket-sized plastic shell that meets all safety certifications for worry-free air travel.

Specifications

• Battery Compatibility: 2x Flat-Top 21700 Lithium Batteries (Replaceable)

• Max Output: 22.5W (5V/4.5A, 9V/2A, 12V/1.5A)

• Input Port: USB Type-C (Supports Fast Recharge)

• Modes: Standard High-Power + Optimized Low-Current

• Safety: CE Certified with 60% Rated Conversion Efficiency

• Included: DIY Charging Case & Dual-Ended Fast Charge Lanyard Cable

Build it. Swap it. Charge it. Upgrade to the future of portable energy with the FlexCharge.