A leisure battery powers much of the equipment that makes a campervan comfortable away from mains hook-up: lights, a fridge, water pump, phone charging and sometimes an inverter. The right battery isn’t necessarily the biggest or newest one. It is the one that matches how you travel and the charging system your van already has.
Start with what you use each day. A battery’s headline amp-hour rating doesn’t tell the whole story.
AGM and LiFePO4: what’s the difference?
AGM is a sealed lead-acid battery. It generally costs less initially and can suit modest, occasional use, but is heavy and typically provides less practical usable energy for a given amp-hour rating if long-term battery life matters.
LiFePO4 stands for lithium iron phosphate. These batteries usually offer greater usable capacity per rated amp-hour, lower weight and a longer potential cycle life. That benefit comes with a higher initial cost and the need to confirm your chargers, alternator arrangements and battery protection are compatible.
| Factor | AGM | LiFePO4 |
|---|---|---|
| Initial cost | Typically lower | Typically higher |
| Weight | Relatively heavy | Usually lighter |
| Usable energy | Limited if avoiding deep discharge | Often a greater proportion of nominal capacity |
| Charging | Correct lead-acid charge profile | Correct lithium charge profile |
| Cold-weather charging | Reduced performance | Charging may be restricted below 0°C unless protected |
Capacity: compare watt-hours, not just amp-hours
An amp-hour figure tells you charge capacity; to compare energy you also need the nominal voltage. For example, a battery rated at 12.8 V and 100 Ah stores approximately 1,280 Wh on a nominal calculation. Actual usable energy depends on discharge limits, battery management, temperature and inverter or wiring losses.
For a quick energy budget, multiply appliance wattage by the time it runs. A 10 W light used for four hours needs roughly 40 Wh. A compressor fridge is harder to estimate because it cycles on and off as temperatures change.
| Illustrative daily appliance | Calculation | Daily use |
|---|---|---|
| LED lights | 8 W × 4 hours | 32 Wh |
| Charging phones and devices | 20 W × 2 hours | 40 Wh |
| Water pump | 45 W × 10 minutes | About 8 Wh |
| Compressor fridge | 35 W × 8 equivalent run-hours | 280 Wh |
| Illustrative total | Before losses and contingency | About 360 Wh |
These are planning examples, not verified test results for any specific appliance or battery. Heat, cold, thermostat settings and the way a van is used can alter real consumption significantly.
Compatibility checks before an upgrade
- Alternator charging: confirm whether the vehicle uses a smart alternator and whether a correctly specified DC-DC charger is needed.
- Mains charger: check it supports the charging profile recommended by the battery manufacturer.
- Solar charging: check your controller settings and electrical ratings.
- Low-temperature protection: some lithium systems prevent charging when the battery cells are too cold.
- Electrical protection: cable sizes, fuses, isolation, battery restraint and ventilation arrangements must be suitable for the installation.
A lithium battery isn’t automatically a safe drop-in replacement. Where there is any doubt, have an experienced campervan electrical installer check the complete system.
Which would we choose?
For infrequent weekend trips with small loads and regular charging, AGM may be entirely adequate. For regular touring and long stays off-grid, a correctly integrated LiFePO4 system is often worth considering for its usable energy and weight advantages. The best choice comes from the complete energy budget, not the logo on the case.
Five questions to ask the seller
- What is the nominal energy capacity in Wh and the continuous output rating?
- What protection does the battery management system provide?
- What happens if charging is attempted in freezing conditions?
- Will the manufacturer’s warranty cover the proposed installation?
- Which charging devices and settings does the manufacturer specify?
Editorial status: Independent desk-research guide. This article does not claim hands-on laboratory testing of individual battery models. Brand-specific review conclusions will be labelled according to the actual evidence available.