21700 Button Top Protected Batteries

Button top protected 21700 batteries combine two features built for device use: a raised positive terminal and an onboard protection circuit.

The button top is a raised positive contact — many devices require it to complete their circuit, where a flush flat-top cell simply won't make contact. The protection (a small PCB built into the cell) guards against overcharge, over-discharge, and short circuit, adding a layer of safety for everyday use. Together they make these cells a convenient, lower-risk choice for powering devices directly.

This is the terminal type to choose when a device calls for a button top or you want the added safety margin of a protected cell — high-performance flashlights and consumer electronics being the most common. (For welding cells into a custom pack, a flat-top unprotected cell is the better fit, since protection circuits and button tops interfere with pack assembly.)

Key features

• Raised button-top terminal for device compatibility
• Built-in protection against overcharge, over-discharge, and short circuit
• Added safety margin for everyday device use
• Ready to use without pack assembly

Common applications

• High-performance flashlights and EDC lights
• Consumer electronics requiring a button top
• Devices needing a protected cell
• Everyday high-capacity, ready-to-use power