JIAJIESHI Battery 3000mAh / 11.10Wh,Replacement Battery Fit for JBL Flip 4, Flip 4 Special Edition
How to Replace Your JBL Flip 4 Battery - YouTube
Amazon.com: High Capacity Replacement Battery + Tool for JBL Flip 4 Speaker or Special Edition Model GSP872693 Li-Polymer 3.70V 3000mAh/11.10Wh Repair Power : Electronics