Lithium Ion Polymer Battery - 3.7v 500mAh : ID 1578 : $7.95 : Adafruit Industries, Unique & fun DIY electronics and kits
4-Pack of ICR 18650 Blue Lithium-Ion Rechargeable Batteries - 3.7V 2600mAh | xUmp.com
EBL 4 Pack 26650 Battery 5000mAh 3.7V Lithium-ion Rechargeable Batteries for LED Flashlight Torch Camera - Newegg.com
Amazon.com: ICR18500 Battery 3.7V 1400mah Li-Ion Rechargeable with Flat Top 6PC(They are not 1865mm Batteries Also Not AA Size Battery) : Health & Household
Amazon.com: EBL 3.7V Li-ion Rechargeable Batteries 3000mAh 18J Rechargeable USB Lithium Battery for Flashlights, Headlamps, Doorbells, RC Cars (2 Pack) : Health & Household
Amazon.com: FPVERA 3.7V 1200mAh Li-ion Battery 2PCS 3.7Volt Rechargeable Batteries with USB Charger Cable SM-2P Plug for RC Car Drift Monster Truck Off-Road Vehicle Remote Control Car High-Speed Climbing Racing : Toys