SuPower 7.2V 7.4V 8.4V 18650 2600mAh Lithium ion Li ion Rechargeable Battery Pack Max. 2A with built in protection circuit board|battery pack|18650 battery pack 7.4vlithium ion battery pack - AliExpress
Amazon.com: Rechargeable Lithium Ion Battery Pack - VIDAR 7.4V 2600mAh High Capacity Li-ion Battery Pack with JST PH2.54/2P Plug-in(Customizable) for Electronics,Toys,Lighting,Equipment : Health & Household