I have spent some time looking for a portable power station to run my telescope and other accessories. I found the Companion Rover unit which has a lithium iron phosphate (LiFePO4) battery with a rating of 40Ah @ 12.8volts. This gives me plenty of reserve power.
The RRP is up around $829 but some stores are currently offering the Companion unit for $559
I bought one yesterday !
It can be recharged using the AC adaptor included, by 12volt input (using the cigarette lighter adaptor - also included) or by direct feed from a solar panel (it has a built-in MPPT controller).
It weighs about 6.5 kg