18650 Battery Ainsworth Kohler May 04, 2017 14:51 Updated Follow Q: Can I use the 18650 battery in the Adventurer opti / Traveler mini / ... A: No. Although the 18650 battery has approximately the same dimensions of two CR123 batteries, a single 18650 battery only has half the voltage of two CR123 batteries. Related articles What batteries do SteriPENs take? Rechargeable CR123s Where can I purchase a replacement Li-ion battery for my SteriPEN? Inserting Batteries into the Classic USB Charger Comments 1 comment Sort by Date Votes Neal Rogers May 04, 2017 14:51 Imagine a Steripen Enduro made with Two 18650 Lithium Ion batteries. It might be a bit larger, but it would run for a long time. Perhaps add a small solar panel for recharging. Perfect for folks with generally robust LED flashlights that also use the 18650 batteries. Sigh... 0 Permalink Please sign in to leave a comment.