All you need to know about the 3.7V lithium ion battery-Tycorun Batteries
3.7 Volt Li-Ion Rechargeable Battery MDHAND (4 Pack) HIGH Capacity 6000mAh,Digital Battery 1C- Flat top - Walmart.com
10PCS 17280 600mAh 3.7v Li-ion Battery cell customized for digital applications | eBay
Amazon.com: PKCELL ICR17500 Battery 3.7V 1100mah A Size Lithium Rechargeable Batteries with Flat Top 2pcs(They are not 1865mm Size Battery) : Health & Household