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Van Battery Cost Comparison: Lithium vs AGM

 

Should you choose a Lithium or AGM battery for your van?
Calculate the cost-effectiveness over 10 years, the weight saving and the true cost of your electricity.

⚡ Your Electrical Requirements

Ah of energy

💰 Current Market Prices

To make the comparison fair, enter the average price you have found for a 100Ah battery from specialist retailers.

€
€

🗓️ Usage Intensity

Battery wear is not measured in years, but in the number of full discharge cycles it undergoes.

Days / year

Financial Summary (Over 10 Years)

LITHIUM Option Lowest Cost
Total capacity to buy: 110 Ah
Estimated weight: 11 kg
Replacements over 10 years: 0 times
Total cost 0 €
AGM LEAD-ACID Option Money Pit
Total capacity to buy: 200 Ah
Estimated weight: 60 kg
Replacements over 10 years: 3 times
Total cost 0 €

Cumulative Cost Over Time

Lithium vs AGM Van Batteries: The Cost-Effectiveness Battle

The leisure battery is the heart of your conversion. It powers your compressor fridge, LED lights, water pump and chargers. When choosing the right technology, van converters are faced with the same dilemma time and again: should you buy a cheap AGM lead-acid battery, or break the bank for a Lithium (LiFePO4) battery?

If you only look at the price on the label, AGM lead-acid batteries seem unbeatable. But in the world of vanlife, this can be a costly trap. Our Lithium vs AGM cost-effectiveness calculator calculates the true "Total Cost of Ownership" over 10 years.

The Ah Myth: Why 100Ah AGM ≠ 100Ah Lithium

The biggest mistake is assuming that a 100Ah battery gives you 100 amp-hours of usable energy. In reality, it all depends on the battery chemistry:

  • Lead-acid chemistry (AGM, Gel): It does not cope well with deep discharges. To avoid destroying your battery within a few weeks, you should never discharge it by more than 50%. So, to have 100Ah of usable energy for everyday use, you need to buy (and carry) a 200Ah AGM battery bank.

  • Lithium chemistry (LiFePO4): It is designed to handle deep discharges without damage. You can use up to 90%, or even 100% of its capacity. A 100Ah Lithium battery will therefore provide 90 to 100Ah of genuinely usable energy.

Battery Lifespan: 500 Cycles vs 3,000 Cycles

The second major factor is longevity. An excellent AGM battery, carefully maintained, will last around 500 to 600 cycles (just a few years if you live in your van year-round). In contrast, a Lithium LiFePO4 battery can easily handle 3,000 to 5,000 cycles, giving it a lifespan of more than 10 to 15 years.

What our calculator shows: Even if Lithium costs twice as much to buy, the need to purchase twice as much AGM capacity to get the same usable energy, combined with having to replace it every 5–6 years, makes lead-acid a real money pit in the long run. And that's without even considering the weight saving (almost 50kg less towards your vehicle's maximum permitted weight!).

📚 Become an expert on 12V systems

Choosing the right battery is crucial. To understand its exact role in your overall electrical system, dive into our comprehensive guide to van electrical systems and power.

Read the Electrical & Power Guide →

FAQ: Batteries for Campervans

How long does a Lithium LiFePO4 battery last?

A good-quality Lithium Iron Phosphate (LiFePO4) battery has an estimated lifespan of between 3,000 and 5,000 charge/discharge cycles. For a vanlifer travelling all year round, this represents an exceptional lifespan of 10 to 15 years, without any noticeable loss of performance.
 

How far can I discharge an AGM battery?

To preserve its lifespan (around 500 cycles), an AGM, Gel or lead-acid battery should never be discharged below 50% of its rated capacity. Going below this threshold causes irreversible sulphation of the lead plates, prematurely damaging the battery.
 

Why is Lithium so much lighter than AGM?

Lithium has a much higher energy density than lead-acid. A 100Ah AGM battery weighs around 30kg, whereas a 100Ah Lithium battery weighs around 11kg. As you need two AGM batteries to achieve the same usable capacity as one Lithium battery, you can save almost 50kg of payload.
 

Can a Lithium battery catch fire?

Older Lithium-Ion (NMC) batteries, such as those used in smartphones, were susceptible to thermal runaway. However, the batteries commonly used in vanlife are LiFePO4 (Lithium Iron Phosphate). This chemistry is extremely stable and is highly resistant to fire and thermal runaway, even if the battery casing is damaged.
 

What is the BMS in a Lithium battery?

The BMS (Battery Management System) is the electronic control system built into the battery. It continuously monitors the voltage of each cell, temperature and incoming/outgoing current. It automatically disconnects the battery in the event of a short circuit, overcharging or freezing temperatures, providing essential protection for the battery.
 

Can I charge a Lithium battery when it is freezing?

No, this is one of its main limitations. Charging a Lithium cell below 0°C can cause permanent damage. This is why the BMS stops charging when the temperature is too low. The solution is to install the battery inside the heated living area, or choose an "Arctic" model fitted with built-in heating elements.
 

Do I need to change my chargers when switching from AGM to Lithium?

Lithium batteries require a specific charging profile (constant current followed by constant voltage, without a desulphation phase). Most modern MPPT solar charge controllers and DC/DC chargers have a "LiFePO4" profile in their settings. If your equipment is very old, you may need to replace it.
 

Does Lithium charge faster than AGM?

Yes, much faster. Lead-acid batteries have relatively high internal resistance: as they become fuller, they accept less current (resulting in a slow absorption phase). Lithium batteries have very low internal resistance and can accept high charging currents (up to 100A) from start to finish, allowing very fast charging while driving with a high-output DC/DC charger.
 

Can I install my Lithium battery on its side?

Yes! Unlike lead-acid batteries, which contain a liquid electrolyte that can leak, Lithium cells are sealed and maintenance-free. You can therefore install the battery lying flat, upright or on its side to make the most of the available space in your furniture.
 

Is an AGM battery a good choice for occasional holidays?

If you only go away for three weeks in summer and a few weekends a year, an AGM battery can still be a financially sensible choice. As you will complete relatively few discharge cycles each year, it could last 4 or 5 years before failing, delaying the point at which a Lithium battery purchase becomes cost-effective.
 

The Electrical Workshop