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.

At the very high level, there are lead batteries, and lithium 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
• Lower useable capacity

While it is possible to use standard automotive batteries that you get at Wal-Mart or the auto parts store as your house batteries, Deep Cycle batteries are better suited to the task. They are designed for more regular/deeper charge and discharge cycles.

• Pros
• Very high energy density
• Light(er than lead)
• Greater useable capacity
• More tolerant of abuse/undercharging
• Faster charge/discharge ability
• Longer lifespan

• Cons
• Expensive, like REALLY expensive
• Requires specialized charge controllers
• Cannot be charged when below freezing (Some drop-in lithium batteries come with integrated heaters to allow charging when ambient is below freezing)
• Charge/Discharge voltage different from lead - many “gauges” will not work

Deep cycle batteries (Primarily lead)

Drop-in Lithium (LiFePO4)

DIY Lithium