My SteriPEN has an internal lithium-ion battery. How should I store it? Ainsworth Kohler November 08, 2016 11:14 Updated Follow To maintain proper battery health during storage, we recommend fully charging your SteriPEN every 3-6 months. Related articles Where can I purchase a replacement Li-ion battery for my SteriPEN? What batteries do SteriPENs take? USB Charger Which SteriPEN model is the best? Which model should I choose? Can I take my SteriPEN through airport security? Comments 0 comments Please sign in to leave a comment.