3.7V 600mAh LiPo Battery Kit for Arduino — Maker Portal
Amazon.com: Blomiky 2 Pack 3.7V 600mAh Lithium Rechargeable Battery and 2 USB Charger Cable Compatible with Fisca Remote Control Robot Dog K9 Battery 2 : Toys & Games
Li Polymer 3.7V 600mAh Battery 3.7v 600mah lithium battery
AKKU CP 17: Cordless phone battery, NiMH, 3,6 V, 600 mAh at reichelt elektronik