Amazon.com : Synergy Digital Camera Battery, Works with Panasonic Lumix DC- GH5 Digital Camera, (Li-Ion, 7.4V, 2100 mAh) Ultra Hi-Capacity, Compatible with Panasonic DMW-BLF19 Battery : Electronics
Can you use GH5 batteries in the Panasonic GH6? | Battery shooting Limitations in the Panasonic GH6 - YouTube
BP 2-Pack of DMW-BLF19, DMW-BLF19e, DMW-BLF19PP Batteries for Panasonic Lumix DC-G9, DC-GH5, DMC-GH3, DMC-GH3K, DMC-GH4, DMC-GH4K Digital Camera - Walmart.com
Juicebox External Battery Pack for Panasonic GH3-, JB-JBGP-01