Amazon.com: 7.4 Volt Lithium Ion Battery Pack (3500 mAh) with Protection IC : Health & Household
Amazon.com: Nitecore Ci4 Four Bay Universal Battery Charger Support 16340 14500 18650 21700 Lithium Ion AA AAA Ni-MH Ni-CD, USB-C QC PD with Lumentac Battery Organizer : Electronics