Adafruit Universal USB / DC / Solar Lithium Ion/Polymer charger [bq24074] : ID 4755 : $14.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Amazon.com: PKCELL ICR10440 Lithium Ion Rechargeable Battery 3.7V 350mAh with USB Charger (2pc Button top +Charger)(They are not AA Size Battery) : Health & Household
Tenergy Premium High Capacity Rechargeable Battery (12-Pack and Charger) Arlo Certified Li-ion 3.7V 750mAh and Smart Fast Charger with LCD