Batteries are the most important part of any vehicle-based electrical system.
Batteries used in your "house" setup have markedly different needs than the battery that's already under the hood of your car. Not that there aren't similarities, but understanding the differences can help you right-size the batteries for your need and avoid battery murder.
Battery Types
At the very high level, there are lead batteries and lithium batteries.
Most nomads planning to install new batteries or upgrade existing systems will choose lithium batteries since prices have fallen considerably during the past few years. Lithium batteries are still more expensive than lead, but the cost-benefit ratio makes lithium an attractive option for most people. However, lead batteries are still a perfectly serviceable option, especially for those who value lower cost above other considerations.
Lead batteries
Pros:
- Less expensive
- Often simpler to use
- Easily obtainable
- Wide range of existing accessories
Cons
- Heavy. Like REALLY REALLY heavy
- Easier to murder if they're not treated properly
- Need to be FULLY RECHARGED every day (realistically, this means you need solar)
- Lower useable capacity
Lithium Batteries
Pros
- Very high energy density
- Lighter weight
- Greater usable capacity
- No need to be fully recharged (in fact, they almost prefer not to be)
- Faster charge/discharge ability
- Longer lifespan
- Harder to damage through improper use
Cons
- Significantly more expensive
- Requires specialized charge controllers
- Cannot be charged when below freezing
- Charge/Discharge voltage different from lead - many "gauges" will not work
