21700 Battery Insulator Rings – Adhesive Fish Paper 200 / 400 / 600 pcs

21700 Self-Adhesive Fish-Paper Insulator Rings – 200 / 400 / 600 pcs

Precision-sized fish-paper insulator rings for 21700 cells — dimensioned for an exact fit on the positive end so they sit flush, with no overhang or gaps. Peel, stick, and prevent top-cap shorts during spot welding and pack assembly.

Product Features

• Exact 21700 fit – OD 19.8 mm / ID 10.5 mm, sized to sit flush on the cell’s positive terminal with no shifting or overhang
• Single-side adhesive – peel-and-stick backing for fast, clean installation that stays put under weld pressure
• Durable fish paper – high dielectric strength and heat resistance
• Ideal for DIY builders – battery packs, e-bikes, power tools, robotics, and energy storage projects

Specifications

• Material: Fish paper (single-side adhesive)
• Outer diameter: 19.8 mm
• Inner diameter: 10.5 mm
• Thickness: 0.2 mm
• Pack sizes: 200 / 400 / 600 pieces

What Is Included

• Your selected quantity (200, 400, or 600) of 21700 self-adhesive fish-paper rings

What Is Not Included

• Battery cells

Good to Know

• Ships flat; larger quantities may ship in multiple envelopes.

Additional Parts and Resources
For nickel, pre-cut busbars, BMS boards, and more rebuild supplies, visit our shop RenewSpark. We also offer the RenewSpark Tools app, built to help DIY builders and professionals with battery-building calculators and utilities.