Using Portable Power Station to charge Batteries in Winter Storage

I have an 2025 R25 that I have just locked away for the winter in a covered storage facility. The parasitic battery drains have been removed. The house, engine, and thruster batteries are currently topped off. Since I am inside this year the solar will not be providing a charge to the batteries. Also, I do not have access to power where I am at. I know I can remove the batteries, bring them home and put a charger on them or I can just wait till spring and charge them up when I commission the boat.
I have already gone down the theoretical road with ChatGPT and Gemini on this question (AI is a little fuzzy on the actual power drawl)
Has any one actually used a portable power station to charge the batteries. Since my boat will be in storage for about 6 months, I was thinking about going down once a month and charging up. In theory the beauty of the solution is that I don't need any special wiring or additional process (Utilizing the the shore cord and the inverter capabilities on the portable power station)...has anyone done this? Any Challenges? What size Power Station did you use? How long did it take to top the batteries?

I use a Bluetti AC 180 to charge the batteries. I have AGM batteries. I do this about once a month. Works well for me since I like to check on things anyway. Amazon has adapters you can buy to plug into the shore power receptacle.

Martin, Thanks for the fast response. Looks like the ac180 is 1800w peak. Very helpful to know your charger does not overload it.

Based on your post/discussion I contacted Bluetti. My flooded 12V batteries have 685 CCA at 10C and 80 Ah. Their recommendation is as follows:

Based on the information you provided,

Single battery capacity: 12V × 80Ah = 960Wh
Total capacity of two batteries: 960Wh × 2 = 1,920Wh
Currently, the capacity of our Elite200V2 is 2073.6Wh.
It can meet your monthly battery recharging needs in winter.

I ordered and received the Bluetti Elite 200 V2 yesterday. It happened to be on sale for 33% off so all in it cost me $1200 CDN delivered to my rural address in BC.

Kevin

Kevin, thanks for your response. I am looking forward to real life monitoring of the charger. My 2 house batteries are 330A each (lithium). The engine and thruster are lead acid. I am curious to see what the actual charge current will be. Since I am topping the batteries off once a month I feel it will not be a full drawl of what the charger is rated at. I have a Victron monitor on the house batteries as well as the engine and thruster. I should be able to see the base condition then how the charger responds. I will report back my finding. I already bought the ac180 so we will see. If it's not enough I will return for a bigger one.

We bought a Bluetti Elite 200 V2 for our extended on anchor excursions. We use a 1m smart plug adpater cable. I've previously posted pictures on the connections and charging adapters. Much easier solultion for us to utilize.

Cliff, thanks, my principle use of the charger is topping off the batteries in the winter. I have been very happy with solar and lithium batteries on anchor with the R25. Being indoors this winter limits any value from the solar. So i am hoping the charging circuit will have a reasonable draw and the AC180 will be enough to handle it. I should be able to give it a first try in a week or two.