Removable Battery for Van AC only

[minifullsizevan]

I currently have a van solar setup. Typical, nothing special. 400amp solar array, MPPT controller, 200ah AGM battery, DC-DC battery isolator/charger. I would like to add a removable (I use the space I would put the battery for snowboards in winter) system for an AC in the summer. My idea is to run another DC-DC charger from my "house" battery to my "AC battery". I would want the "AC battery" to only charge when the "house" battery is full so I might be without AC sometimes but would still always have power in the "house". I would like to use a lithium battery for the "AC battery". I can not see any issues with making this system. Im hoping for any advice or issues I may run into. Thanks in advance!!

 

[HarryN]

Do you have an inverter to run a 120 vac air conditioner?

The 12 volt air conditioners really are not that powerful.

To run a viable van air conditioner for 4 hrs will take approximately 4 kW-hrs, so the equivalent of 400 - 500 amp-hrs of 12 volt LiFe battery capacity.

Is this what you are thinking ?

 

[minifullsizevan]

I currently only run a very small inverter that I use only for my Laptop. I planned on installing the "B-Cool 12000RM-RV – 12 Volt DC Air Conditioner (11,253 BTU)". I was looking at a 300ah LiFe battery. I live in/near the mountains in CO so AC is not always needed. Alot of time I can just plan where Im sleeping at a high altitude and be fine with just a fan or maybe AC for 20 mins or so. Ive been just running my vehicle AC for ~20 mins most nights and its fine on most nights. I would only plan on running it 2-3 days out of a week and probably only for 2-4 hours those days. Alot of the times Id be running it would be on a trip out of state, which are usually only a couple days, max a week. I will probably be adding a shore power source as well so I can "top" off the battery when power is available.

I can be convinced of other plans at this point as far as using an inverter and 120v AC. If you have used the 12v ACs before and do not believe they would work for my application. Im only in the research portion right now.
Thanks for the input!

 

[henrys]

That air conditioner is $2800 and still pulls 800-1000 watts of power. You're still going to need a LOT of battery to run that for any decent amount of time and then you're going to need a lot of charging to get that battery topped up again.

 

[featherlite]

Looks like that Air Conditioner costs about $2,800, and, as advertised, uses 50-75amps when running, per hour.
Take some time to calculate how many hours you could run that Air Conditioner with that proposed 300Ah battery and how much solar input you would need to produce per hour in order to keep the battery charged.

 

[0truck0]

Sorry, bud. This is a dream we all have, but it will not work.
You need way way more battery power than you have. AC needs major amp hours behind it to be of any use.
Your van is a problem, its a van, too many windows and probably too poorly insulated, so all an AC would do is blow cool air on you, not cool the van.. the size AC you are going to have with such a small battery.
For your infrequent AC needs it makes little sense to try to make a battery work.

What you got to do is knock out the glass on the rear window, fabricate and install a panel in the place of the glass and make a hole for a tiny $99 window AC unit. Power that AC unit with a small inverter generator. Leave the generator at home in the winter.