Lithium batteries are an increasingly popular option for house batteries for nomads. Prices for these batteries are continuing to fall, making them a more attractive choice due to their significant advantages. The nomad's alternative to lithium batteries is lead batteries.
There are two methods of obtaining a good lithium battery setup:
LiFePO4 batteries — factory-built batteries that you can (mostly) treat like any other battery; they're a sealed black box that already contain a Battery Monitoring System (BMS), safety cut-offs, and sometimes Bluetooth monitoring.
The more industrious (or frugal) can go the DIY Lithium path. This is where you buy the raw cells (usually at a deep discount directly from China), a BMS, cables, and bus bars, and build the battery packs yourself. Done properly, massive capacities can be had for prices so low it's not much more than a good lead battery setup.
Lithium battery history
Early lithium battery chemistries were an attempt to get much greater power-to-weight ratio than was achievable with lead, NiCad, NiMH, etc. Lightness and power are extremely useful in aviation, space launches, RC racing, etc. A side benefit is that lithium does not suffer from Partial States of Charge like lead does.
Unfortunately for nomads, early lithium batteries had cell voltages that didn't line up well with 12v applications, and a disconcerting habit of entering thermal runaway (ie, violently catching on fire). LiFePO4, the current lithium standard for nomadic use, is much more stable and have cell voltages that work well with 12v power systems. The downside is lower energy density.