The insulating ring on the battery is the most important part of the insulation alongside the heat-shrink tubing. It protects the battery from unintentional short circuits on the front side (positive terminal) where the risk of a short circuit is highest due to the proximity of the terminals.

Insulating rings (insulating discs) for 21700 batteries.

Application examples: Re-shrinking of batteries.
The insulating rings are temperature-resistant up to 150 °C and self-adhesive on one side, so they can be attached easily and without great effort when re-shrinking.

Size: outer diameter: 20 mm; inner diameter 11.5 mm; thickness 0.3 mm

Scope of delivery: 1 piece contains 8 insulating discs.
With a purchase of 5 pieces, 40 insulating rings are supplied.

We also have heat-shrink tubing in various colours to match the insulating rings. Cut to fit 75 mm for 21700 cells. Article number: 400514

Tips and safety:

Replace damaged protective sheathing and insulating ring. Attach additional heat-shrink tubing and additional insulating disc to increase safety (particularly important for industrial cells). Replace already worn or damaged insulating rings or heat-shrink tubing.

Many battery suppliers for everyday use such as Efest, Keeppower, Enerpower etc. already fit their own batteries with hard-wearing PVC shrink sleeves to ensure safety in use. As industrial batteries are built for further processing, the protective coating of the cells is not sufficient for daily use. A damaged protective sheath can quickly lead to fatal consequences for Li-ion batteries. (short circuit, fire, explosion, etc.)