EEMB 3.7V Lipo Battery 500mAh 403048 Lithium Polymer ion Battery Rechargeable Lithium ion Polymer Battery with JST Connector Make Sure Device Polarity Matches with Battery Before Purchase!!!
3.7V 25mAh Small Size Lipo Battery Rechargeable For Mp3 GPS Bluetooth 401015 | eBay
Why aren't there Lithium Ion rechargeable batteries in AA and AAA sizes? - Quora
Let's Talk Batteries! Probably the Most Confusing Topic--But Most Important! - Fenix Store