Short answer: caravans typically run on a 12-volt leisure battery to power 12V appliances when not connected to mains. The exact battery type varies, with options ranging from traditional flooded lead-acid to AGM, GEL, and modern LiFePO4 (lithium) cells depending on needs and budget.
Caravan electrical setups vary widely, and the choice of battery depends on how often you stay off-grid, how much power you use, how much weight you can carry, and how much you’re willing to spend. This article explains common battery chemistries, how to size capacity, charging options, and typical configurations you might encounter in modern caravans.
Common battery chemistries for caravans
Caravan leisure batteries come in several chemistries. The most common are:
- Flooded lead-acid (often called "wet" batteries)
- Absorbed Glass Mat (AGM) sealed lead-acid
- Gel sealed lead-acid
- Lithium iron phosphate (LiFePO4)
Each chemistry has trade-offs in cost, maintenance, weight, and usable capacity. Flooded batteries require water top-ups and venting, while AGM and Gel offer maintenance-free sealing. LiFePO4 provides higher usable capacity and lighter weight, but at a higher upfront cost.
How much capacity do you need?
Sizing depends on daily power use and how many days you want to stay off-grid. Typical caravan lifestyles fall into these ranges:
- 60–100Ah for occasional weekend use with modest power draw
- 120–200Ah for regular off-grid stays with multiple devices
- 200–400Ah or more for full off-grid living with high consumption and solar charging
Note the depth of discharge recommended for each chemistry: lead-acid batteries are typically kept to 50–80% discharge to maximize life, while LiFePO4 can often be discharged to 80–90% usable capacity with appropriate BMS protection. Actual practices depend on the specific battery and manufacturer guidance.
Charging and maintenance basics
Batteries in caravans are charged from mains power, the vehicle's alternator, and solar panels. Proper charging and maintenance extend life and reliability:
- Use a charger that matches your battery chemistry and an MPPT controller for solar setups
- Keep flooded lead-acid water at recommended levels; sealed batteries require less maintenance
- Install a battery management system (BMS) for LiFePO4 and ensure proper venting for lead-acid systems
- Inspect terminals for corrosion and secure the battery to prevent movement during travel
With the right charging strategy and routine maintenance, your caravan battery can last several years, especially with LiFePO4 when budget allows.
Configurations you might encounter
Caravan electrical installations vary, but several common configurations are widely used.
Single leisure battery
A single 12V deep-cycle battery powers the caravan’s 12V circuits when not connected to mains power. Typical capacities range from 100–120Ah in older or simpler setups.
Dual-battery (split-charge) systems
Two batteries are used, often with a split-charge relay or DC-DC charger to prevent draining the vehicle’s starting battery. This improves reliability for longer trips and heavier load profiles.
Lithium upgrade
Upgrade to LiFePO4 for more usable capacity, longer life, and lighter weight, typically paired with a capable BMS and appropriate charging equipment. Higher upfront cost, but potential long-term savings and performance benefits.
Solar-assisted / hybrid setups
Solar panels and an MPPT controller complement the battery, increasing off-grid autonomy. Proper sizing is essential to maximize daytime charging without overloading the system.
Summary
The practical answer is that caravans generally take a 12V leisure battery, with options ranging from traditional flooded lead-acid to modern LiFePO4 systems. The best choice depends on how often you go off-grid, how much power you use, and your budget. With proper charging, maintenance, and configuration—whether single, dual, or solar-assisted—you can ensure reliable power for your caravan adventures.