TinyCircuits
LITHIUM ION POLY BATT 3.7V 290MA. Battery Packs Lithium Ion Polymer Battery - 3.7V 290mAh
Seiko Instruments
BATT LITH 3V 3.4MAH COIN 6.8MM. Coin Cell Battery Recharge Battery/Tab RTC/SRAM Backup
Seiko Instruments
BATT LITH 1.5V 2.5MAH COIN 6.8MM. Coin Cell Battery TS621E W/Tab RTC/SRAM Backup