Walther battery 21700 Li-ion 3.7 V 5000 mAh - Tactical24 e-Store
Amazon.com: HXJNLDC DC 3.7V 2100mAh 804050 li-ion Lithium Ion Polymer Battery Replacement for DIY 3.7-5V Electronic Product, Mobile Energy Storage Power Supply : Electronics
Amazon.com: EEMB Lithium Polymer Battery 3.7V 250mAh 502030 Lipo Rechargeable Battery Pack with Wire JST Connector for VXI Blue Parrott- Confirm Device & Connector Polarity Before Purchase : Health & Household