I recommend a LiFePo4 battery. Why because it will stay above 12 VDC until around 90% drain while a conventional battery or deepcycle will drain below 12 vdc at or before the 50% usage.
So a 12vdc with rating of 35HA would list around 420 watts available. Sure but the voltage will drop to almost 8 vdc. It is recommended to only use 50% of the rating or about 200 watts on lead acid.
Batteries are made for specific use. A car battery is made for quick and short high demand with immediate recharge. Deepcycle are made for lower demand for long periods and should be recharged as soon as possible after use.
You can research the reasons why. LiFePo4 are also build for different purposes. I use the deepcycle type rating. They do not need to be recharged immediate. When stored for long periods, they loose very little while a deepcycle needs recharging after just a month.
A LiFePo4 12.8 vdc rated at 65ah weights under 20lbs. These will provide at least 650 watts before going under 12 vdc. I have one of these and also a 100ah that can run everything including my laptop for 3 to 4 days.
About a week ago I did 6.5 hours of imaging with my CGY, 2 x dew heaters set at 40%, ASI071MC cooler on to -5c, guider and minipc, only used 80 watts for the whole session. Laptop was in the house as everything is remotely controlled.