Lithium Ion Polymer Battery - 3.7v 500mAh : ID 1578 : $7.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Amazon.com: Blomiky 2 Pack 3.7V USB Charger Cable with SM-2P Plug Connector for Small RC Amphibious Stunt RC Car Boat Trucks 3.7V Li-ion and Li-Polymer Battery 3.7V USB 2 : Toys &
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EU 110V 220V Dual 81650 3.7V Battery Charger
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