MB gravity power supply

[hooked on smoke]

If this is in the wrong spot I'm sorry.
I looking for recommendations on a cordless power supply to run my MB gravity 800, and possibly the MB rotisserie at the same time.I have a power bank I purchased off of Amazon but it just doesn't last. Cuts off at any given time. I'd like something more reliable.
Thanks in advance for any information offered.

 

[JLinza]

I've ran my MB 1050 for a couple hours of of something similar to this...

Using Dewalt batteries. Might have to use a few batteries for a longer cook, depending on the Ah of your battery. Not sure if you have the resources to set this up but. It's an idea that I've used.

 

[Smokin Okie]

Thermoworks makes a power bank to run their Billows. I don't know why it would not work on a MB. I don't know anything about this product but Thermoworks makes solid stuff.

https://www.thermoworks.com/billows-12v-battery-bank/