Lithium Ion Polymer Battery with Short Cable - 3.7V 420mAh : ID 4236 : $6.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Rechargeable lithium battery type 21700, 3.7V 4000mAh
Li-Polymer Battery 3.7V 6000mAh
Buy MAENT® 3.7V 1000 mah Actual capcity lipo Li ion Rechargeable Battery Lithium ion Polymer Cell for Bluetooth Science Project Toys MP3 GPS PSP Handheld Device - NOT for RC CAR OR