I use this 100Wh Li-ion battery pack to power my portable setup:
https://www.amazon.co.uk/dp/B06Y5G3C8Z
It only weighs 0.5 kg and it has 5V USB and 9V regulated DC outputs and a 12V unregulated output direct from the internal cells (which I think are LG 18650s). 100Wh is small enough to take on a plane as cabin luggage but it is large enough to power an AM-3 and an ASI camera with cooler for > 5hrs.
Since the 12V is unregulated it drops below 11V at around 50% capacity so I use an in-line DC buck converter to boost the raw voltage to 13.8V. With that, the AM-3 and camera are happy through to around 90% discharge. You wouldn’t need that if you are using the 5V or 9V outputs.