https://smile.amazon.com/gp/product/B06WW8YMMJ/ref=oh_aui_search_asin_title?ie=UTF8&psc=1
I bought a 2nd one just to have it after I received my original. Accubattery reporting it as 3120 mah after tracking for over a month.
It's so good I'm literally in the same debate I had on black friday again... Best Buy has the Pixel 3XL for $450 off and that phone is incredible (bought for wife). Yet, I still love my V20 and the battery still lasts all day under general use. Heavy use I'm only getting half a day, but I have lots of places to plug in, plus that spare battery if I really need it.
I recently got this PowerBear one and it's been working fine so far. I don't do a whole lot of video watching or game playing, but I haven't experienced any heating issues.
Link: PowerBear LG V20 BATTERY [3200 mAh] Li-Ion Battery for the V20 [US996, AT&T H910, T-Mobile H918, Verizon VS995, Sprint LS997] LGV20 Spare Battery [24 Month Warranty] https://www.amazon.com/dp/B06WW8YMMJ/ref=cm_sw_r_cp_apa_.XYBBbVGWD0DY
I'm in the market for a new battery for my LG V20 as well since my extended TQTHL battery started swelling up. Which is more reliable, Powerbear or Gorilla Gadget?
https://gorillagadgets.com/products/lg-v20-replacement-battery
These all seem fine:
https://www.amazon.com/PowerBear-BATTERY-Battery-T-Mobile-Warranty/dp/B06WW8YMMJ
https://www.amazon.com/BL-44E1F-AexPower-Replacement-Worry-free-Warranty/dp/B01MR3B04S
https://www.amazon.com/JUBOTY-BL-44E1F-Replacement-Charging-Warranty/dp/B07BHFLM5V
I personally own the AEXPower one, and haven't had issues.