Totally possible, but you definitely still need a fuse so you don’t burn down your house. That charger isn’t high amperage but still enough to harm you. And definitely make sure that battery has a good BMS with over current protection. If you overcharge lithium batteries (even LFP) they tend to go poof. I hope that charger is programmable or configurable. If not, you risk over charging the battery. The stuff on Amazon always looks inexpensive, but it’s really just Chinese companies dumping off cheaply made products with no oversight or regulation.
Also your charging method is only to charge up the external battery. You still need a way to “pull” the energy from that external battery back into the Bluetti. For that, you need an DC-to-AC inverter. That would then push 450watts at a time into the Bluetti. Alternatively, you can use some other high voltage DC-to-DC step up inverter to max out the Bluetti’s PV input port. (145V, max of 15A on the AC200Max)
You CAN try to use the 12v cigarette lighter input port on the Bluetti (and again more fuse banks, shunts, and maybe a DC-DC step down converter) and at best it’d be 100w at a time since the input port on the Bluetti only allows 12V/8.1A (12 * 8.1 = ~97.2 watts). Meaning it’d take 12 hours to fully deplete that battery into the Bluetti. And you won’t get the full 1.2kWh dumped into the Bluetti. Probably 80-90% of that. And you’d still probably have to monitor it manually. You’d also need a female cigarette lighter socket wired into the battery.
I like answering your questions. Happy to help. Glad you are learning.
Thank you for that, Cyan, I appreciate the answers.
I was only mulling it around in my head, just wondering, and I assumed that since battery charges, especially well-made ones, they could probably already have what they needed, so maybe that was not correct.
Believe me, I know full well that stuff on Amazon and the rest too, they have junk, I personally only buy stuff that has a (recent) excellent review. Of course it all depends on the 'thing' I am looking at, but mostly I go by that. Amazon is just easy, that is why they are so popular, I use them to 'find' things, then I shop from there, whether it be there, or somewhere else.
Anyway, what you said is very helpful, and I am glad that people (like you) take the time to help others learn, that is how YouTube was in its infancy, if you remember, and I miss that.
Again, I don't even pretend to know all of what you said, but, as long as this site is up and running it will be here for me to delve into, which I am sure I will.
In most ALL of my thinking is due to the recent news that here in Texas (and other states too) that we will probably have Winter black-outs, I am just trying to think of what is possible with 'just a battery' in case of an emergency. (or,
batteries)
That battery charger was not one of the ones that I'd buy, I just typed in battery charger and went for it, I did see one that was specifically made for LifePO4 batteries, I think that one was too, but it was a cheap-o.
I don't want to jump head first into all that goes into a normal build here, I am not made for that, hence the Bluetti.
Still, I will be looking at how things are done, and learning a little bit, and I do mean a little bit.
I will more than likely at some point be more serious, with some actual learning under my belt in the near future about the DC-to-AC inverter you mentioned.
Right now I have my refrigerator running on my AC200P as a test, I'll see what it can do in actual time. I learn best by just doing it.
Thanks again for you time, and I am sorry I was so wordy, but this, when I learn, is kind of fun. Well, more fun than it was.