I use a lot of the BLC12 Batteries. I buy the Panasonic ones; they aren't cheap but they last the longest and don't turn the camera off with no warning.
However, I do buy aftermarket batteries for testing from time to time. They often have very high ratings, and they never work very well.
A few years ago, I bought the DSTE "1600mah" battery. It had about 70 percent of the stock battery's power, and the stock battery is 1200 mah. So that's 840mah, or about half the advertised capacity.
A few weeks ago, I purchased the 1700 mah version at this link:
https://www.amazon.com/dp/B00MEAMBQU
It weighs 55 gm as opposed to the stock 50gm. Previous clones weighed 46 and 48 gm.
Now before you get excited, the extra weight is probably ballast, since you can't squeeze more cells into a battery, as a general rule.
However, after extensive testing, this battery is equal to--not better--but equal to stock. The only difference is that the shutdown curve is a bit steeper.
So it isn't "1700" mah, but it is basically a stock battery.
This was quite a shock, but I repeated the tests several times. In one test, I simply turn on the camera and record video until the battery croaks, and measure the time. Both the stock battery and the DSTE run the G7 for two hours of video, sometimes a few minutes more, sometimes a few minutes less. So, finally, an inexpensive option. At least for this batch. Also, see my post on the cheap external battery that will run your camera all day.

I purchased this one.

https://www.amazon.com/gp/product/B073XYYYWR

There's another model that has two USB inputs, so you could use two power banks or use one and draw more amps.

I was skeptical, and the packaging made me even more so, cardboard & crinkly shrinkly, but I plugged it into my cheapest 5200mah power bank and measured the voltage. 8.8 volts, which is just about right (I've gone as high as 9.2, but prefer not to). Notably, the needle on my trusty voltmeter did not wiggle. Also noteworthy, it didn't seem to need the recommended 3 amp draw. It comes with a 3 amp wall wart if you just want to plug the camera into the mains for power.

It comes with a bog standard dummy battery. The step up converter is tiny, not much thicker than the cable. Plugged in the camera (Panasonic G7) and waited. The 5200mah power bank ran the camera for 156 minutes, or two and one half hours. Not bad--you are going to lose some power in the conversion so don't skimp on the power bank. I'll do some tests later with my RAV 20,000mah bank.

Camera ran cooler than expected.

So there you have it, easy, lightweight power from USB. I had been using 9 volt packs with stacks of Panasonic 18650 cells (runs forever....). But this is really easy.

You can buy adapters for most cameras, and considering the fact that it comes with a dummy battery, the price is cheap. Will it burn out? Interesting question.

[Added formatting and photo, VK]

After some months I bought Nokton 17.5 mm and Panasonic G6, then Phantom 3 Pro and last year Panasonic 100-300.

As my hobby and side job, I shoot videos of weddings, cultural events, and so on. Recently I got idea to step up and upgrade my gear, but I found myself teared up between so much choices. Because of my past experiences, I tend to favourites Nokton lenses. I idealize having whole set of them.

From last year I saved up enough from my videography to afford to buy Voigtlander 10.5 mm, 25 mm and 42.5 mm, with Panasonic G85 body (althought I would spend all of that money saved from videography from last year). For some time I worried that Voigt lens are not stabilized, but Pan G85 body is, so that is good. Idea of having whole Voigt set seems like perfect step up in my videography. Manual focus is still challenge for me, but with 17.5 mm I got used to it and even quite cherish it. What makes me confused are 3 things:

1) Thought of trying to get used to Panasonic lenses with not-so exclusive build quality keeps me from buying one. But I could buy used for 2 years, functional Panasonic Nocti 42.5 mm f/1.2 for 800 dollars, and use it for both videography and photography too (autofocus and stabilization), so it seems like no brainer, but I tend to cling to Voigt lens with my heart. And having whole set of Voigts would keep my "style" somehow unified maybe? If I would take photos with Voigts I would be probably frustrated (with moving objects)... on the other hand this way I could train manual focusing for my videos. So as you can see I am really confused with both options. For same money I could have new Voigt 42.5 mm (I live in Central Europe, so buying electronis from foreign countries is not possible due to high fees).

2) Second problem with buying almost whole set of Voigt lens (10.5, 25, 42.5 and Panasonic G85) is money. I can afford it, but man, it is a lot of money. Even worry of theft of my gear comes in mind. On the other hand, with possibility on reach, I would love to play with all those Voigt lenses in different situations for different purposes on upcoming projects/events...

3) I counted with Nokton 10.5 mm for purpose of using it in future on one of those new one-hand-gimbals, but althought I saw smooth videos of this combo, I saw bad review too (too heavy-front for some gimbals). Officialy weight-wise it is under norm though, so I would have just to try it first I guess...

What do you think? What would you do? What should I do? :-)

Thanks a lot for your answer.

I was satisfied with the IBIS, especially when paired with a Panasonic lens.