Source 5v rechargeable battery 18650 battery 5V Type C USB 3.7V 5200mAh lithium battery pack on m.alibaba.com
BiXPower MP100-15V
Adafruit PowerBoost 500 Shield - Rechargeable 5V Power Shield : ID 2078 : $19.95 : Adafruit Industries, Unique & fun DIY electronics and kits
SD504065 3.7V rechargeable battery pack 1500mAh ,rechargeable 5v li ion polymer battery - AliExpress
Source Light weight and small size 12V 5V Li-ion rechargeable polymer battery +AC Aadpter US/EU/UK/AU 12V 1800mAh/5V 6800mah USB output on m.alibaba.com
Talentcell Rechargeable 12V 6000mAh/5V 12000mAh DC Output Lithium ion Battery Pack for LED Strip and CCTV Camera, Portable Li-ion Power Bank with Charger, Black