How do I set up my RV energy system?

I'm wondering if anyone has successfully plugged in a portable solar generator or any similar re-chargeable lithium battery bank via your RV Hookup?
I have a 50 Amp hookup and I'm curious if I got a 12V 50Ah portable solar station if I could use a dog-bone adapter from 50A to 15A connector and run a few items (LED Lights, Bathroom fan, water pump) I've calculated everything and I use around 1.5kWh a day. If I had everything on at once, it would be about 355W and 7A. And if I go over usage, I would be recharging fairly quickly here in the South with a lot of sun-time.
Is there a better idea for doing something like this? I'm interested in a plug-in play lithium system because I want it to be as maintenance free / 'set it and forget it' as possible and because I don't have a clue on where to start to build my own. However, I'm completely open to something DIY that would be cost effective and someone easy.

Popsail Answer:
12V 50Ah lithium battery portable station may not enough for providing the enough power to run such a long time. The estimated electricity consumption per day is 1.5KWh, But the 12V 50Ah lithium power station is only able to offer 600Wh(100% DOD!). 

The good available option is that install the 12V 120~150Ah Lithium battery into your RV and the fuse box to make the power distribution which will protect your loads better. It also makes sense to take an portable folding solar panel, like 100W or 120W for the extra charging source. 

Here is the calculation for reference:
Daily power consumption: 1500Wh(1.5KWh)
Battery output capacity(80% DOD): 12V×120Ah×80%=1440Wh(1.44Wh)
When the RV is stopped, the solar panel makes supplementary power to charge the battery. Let's see charge for around 4 hours;

According to this calculation, the power can offered per day is around 1440Wh+300Wh=1730Wh(1.73KWh) which is a little bit larger than the power requiement 1.5KWh. 
When the vehicle is on the going, this lithium leisure battery can be charged by the alternator. Also the extra AC charger is also necessary for more than 2 rainy days. 

My RV is hooked up to solar. I turned the generator on and plugged in the RV to shore power without turning off the inverter. It popped and smoked. Green light turned orange. Did I f it up for good? Can I even turn it on again? Could I have blown anything else? Generator, fuses in the RV...inverter says auto transfer, and there is an ATS to manage two AC groups.

Popsail Answer:
Basically yes, your inverter has been burnt by the external AC input. The AC output from inverter 100% ran straigthly to the AC input from the generator. 
Inverter is the weakness thing which has a fast blow fuse to make the rapaid protecion. Generator could be survived at a high possibility, the AC circuit breaker should also be opened.  

Please be very clear of the ATS. The diagram should be this:

RV solar system with ATS generator and shore power

Looking to get a 35ft RV for next year but I’m curious about power generation. Going to be kitted out with TV, water heater, AC etc don’t want to cook on LPG either.
Mainly I’m wondering if solar is a better option than a generator and I've also seen a high powered alternator on the market...any thoughts on these also?
We want to mainly boondock around and use the occasional RV camp.

Popsail Answer: 
Solar power is a very good option, clean, endless energy from solar and easy to get.  No diesel smell and no noise. If you are not the super diesel generator fan, there is no need to install the diesel generator to power these loads. 
TV, water heater, outlets for laptop charger/phone charger, mircowave, etc are all available by solar. 
Firstly measure how much energy you would need, and install a larger battery bank to support the total off grid use. Popsail has the guidance of the RV solar power system building, please follow this system design article:

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