I've logged hundreds of hours on the G9 and the Wasabi Power DMW-BLF19 2000mAh Battery is the most consistent performer for the price. I once ran a side-by-side discharge test against the OEM cells and these held about 90 percent of the capacity for a fraction of the cost. They use high-quality Grade A cells so they wont swell in the chamber during long wedding sets.

Unfortunately Ive had issues with batteries swelling and getting stuck in the slot, which is a nightmare. Most cheap generic ones are garbage, and one nearly ruined my G9 during a shoot. For a wedding, dont cut corners too much but these are decent budget picks:

• SmallRig DMW-BLF19 USB-C Rechargeable Camera Battery 2400mAh
• Watson DMW-BLF19 Lithium-Ion Battery Pack 2000mAh SmallRig is handy since it charges via USB-C. Just dont leave em in the heat.

Building on the earlier suggestion, I've been shooting with the G9 since it launched and I've tried a ton of different setups. I remember being super nervous at my first big gig, worrying about the camera dying mid-vows. I ended up picking up some Kastar DMW-BLF19 Replacement Battery 2100mAh packs because they were cheap and had decent reviews. They've actually been surprisingly solid over the last couple years. I also messed around with the Powerextra DMW-BLF19 Replacement Battery 2200mAh units and they seem to hold a charge just as well as the original Panasonic ones. They don't have the fancy bells and whistles like internal USB ports, but they work. I haven't had any issues with swelling yet, which is the main thing you gotta watch for with the budget stuff. If you're in Ohio, you should be able to get them delivered fast enough through most major retailers. Just make sure you cycle them once before the big day to make sure they're holding a full charge.

I agree but unfortunately third-party batteries are rarely as good as expected. I've found BM Premium DMW-BLF19 2000mAh Battery Pack to be more reliable and less prone to swelling up.

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