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4 Ways To Charge A Camper Van Leisure Battery

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Most camper vans carry an auxiliary battery to provide power to all the personal electronics inside the vehicle. This includes laptops, lights, fridge, vent fan, and more. If the batteries run out of charge, you won’t be able to power any of your devices. That’s why it’s critical to learn about all the different ways you can charge a camper van leisure battery.

For most van lifers, there are four ways to charge a camper battery.

  • Solar charging
  • Alternator charging
  • Shore power charging
  • Generator charging

In this post, we go over each of these common charging solutions, their pros & cons, and essential product recommendations, if you choose to utilize that specific charging method. At the of the post, we discuss which of the four charging solutions we use in our own camper van and how much we rely on each solution to provide power to our batteries.

So if you’re ready, let’s dive into it.

1. Charge From Solar Panels

Utilizing solar panels is a popular way that camper vans charge their leisure batteries. Solar panels convert sunlight into direct current (DC) electricity, which is then stored in the batteries through a charge controller. Because of their renewable, eco-friendly solution, van lifers are increasingly turning to solar power as their primary charging solution.

One of the best aspects about having solar panels is that the charging process is entirely passive. As long as the panels are receiving sunlight, they will be sending electricity to the batteries. No other work or actions are required on your part. You can be wild camping miles away from civilization and your batteries can still be receiving power from the solar panels.

Two solar panels on a camper van

Below, we provide a two-step process to help you determine how much solar power you need to keep your batteries charged.

  1. Calculate battery size – Use our battery calculator to help you determine what size battery bank you need.
  2. Calculate solar size – Once you know your battery size, use our solar calculator to derive your ideal solar array wattage.

When you’re ready to install solar panels on your camper van, read our solar panel mounting post. Next, read our solar guide to help you wire the panels to your batteries.

We also provide solar and electrical wiring eBooks that are completely free to download and use. They include helpful wiring diagrams and useful product recommendations.

2. Charge From Alternator

Camper van batteries can also be charged by receiving power from the vehicle’s alternator. An alternator is a device that connects to the van’s motor and generates electrical power when the motor is on. The purpose of the alternator is to charge the vehicle’s starting battery when driving.

Therefore by connecting the leisure batteries to the starting battery, which already connected to the alternator, these auxiliary batteries can also receive a charge every time you turn on the engine.

In order to do this you will need to connect the leisure battery to the vehicle’s starting battery with either a split charge relay or DC-DC charger (preferred) in the middle.

  • Split Charge Relay (Battery Isolator) – Cheap device and easy to install, but requires leisure battery to be the same chemistry (AGM) and same age as the starting battery. Does not work with lithium batteries.
  • DC-DC Charger – Charges leisure battery from the starter battery and controls the voltage to ensure leisure batteries, of any chemistry, receive a proper full charge. Works with lithium batteries.
DC-DC charger wiring diagram for camper vans.
Complete DC-DC charger wiring diagram

Recommendation: If your leisure batteries are a different chemistry type than your vehicle’s starter battery OR there is a significant age difference between the two batteries, use a DC-DC charger. Below, we list a popular split charge relay (MaySpare) and DC-DC charger (Victron).

For more information, read our DC-DC charger installation post.

3. Charge From Shore Power

The term ‘shore power’ is defined as any electrical socket outside a camper van that is connected to the main power grid. A shore power socket could be located at a campsite, in the garage of your house, or even at a gas station. However, because shore power is supplied in alternating current (AC) power and the batteries operate on direct current (DC) power, you will need the right equipment, to utilize shore power sockets to charge your batteries.

Most camper vans use inverter/chargers to charge their batteries from shore power. Inverters typically take DC power from the batteries and convert it to AC power. However, if you get an inverter with an additional charger module, you will also be able to convert AC power back to DC power, to charge the batteries.

Note: Inverter/charger combo units tend to be significantly more expensive than a simple inverter.

Renogy 2000W Inverter/Charger
Converts 12V DC to 110V AC to power laptops and other household appliances. Also comes with a charger unit to charge camper leisure batteries from shore power.

For more information, read our inverter installation post.

Budget Alternative: If an inverter/charger is outside your budget, consider a simple 20A battery charger. It's small and can delivery a powerful 20A of power to your leisure battery. The recommended charger below is compatible with both AGM and lithium batteries.

4. Charge From A Generator

Leisure batteries can also be charged by connecting them to a portable generator. Most generators require either gasoline or propane (LPG) to run. Generators are convenient because you don’t need to rely on sunlight or to drive in order to function. As long as you have gas or propane, the generator will provide ample power to send a charge.

However, portable generators are not popular within the camper van community because they can be loud when turned on. We wouldn’t want to be wild camping in a pristine, quiet setting only to have the moment ruined by a loud generator humming in the background. Some campgrounds also do not allow generators to be used because of their noise. And if they aren’t prohibited, we doubt your neighbors would enjoy hearing your generator churning out power.

But generators can be useful in emergency situations. So for some, carrying a small portable generator, like the recommendation below, can help provide power as a last resort.

How We Charge The Leisure Batteries In Our Camper Van

Having sufficient power to run our electronics is critical. Because we work remotely, we value power reliability and cannot afford for our batteries to run out of charge. That is why we set up our van’s electric system so that we can charge our leisure batteries in three different ways.

1. Solar Panels (360W)

We installed two 180W solar panels on our van’s roof and feed the power through our Victron charge controller to the leisure batteries. One a long & sunny summer day, we’re able to put back as much as 1.8kWh back into our batteries. And on average, the solar panels provide roughly 60% of the total power used to charge our batteries.

2. Alternator Charging With DC-DC Charger

We also connect our leisure batteries to the van’s alternator through a DC-DC charger. We opted for the DC charger, instead of the cheaper split charge relay, because our lithium (LiFePO4) leisure batteries are a different chemistry than our AGM starter battery.

The DC-DC charger works great when the solar panels have been sitting in the shade and were not able to supply sufficient power to our batteries. But with the DC charger, our batteries can still be charged back to full after just a few hours of driving. On average, the DC charger provides roughly 25% of the total power to our batteries.

3. Shore Power Charging With Inverter/Charger

Finally, we can also charge our leisure batteries by connecting to shore power with our inverter/charger. When plugged in, our Victron inverter can put ~750Wh of power back into our batteries each hour. However, because our solar panels and DC-DC charger already do such a good job in keeping our batteries charged, shore power only provides roughly 5% of our power charging needs.


If keeping your camper van batteries charged is as important to you as it is for us, we can’t stress enough the importance of utilizing at least three different battery charging methods. Doing so virtually guarentees you’ll have sufficient power throughout your van life journey.

If budget is a concern, skip shore power charging and focus instead on solar and alternator charging solutions. These two methods will be where most of your power comes from.

If you have any other battery charging related questions, be sure to send us an email to the address listed in our footer.

Happy building!

Thank You For Reading!

We’re Yuko and Eric! We both grew up in Asia ( Japan & Hong Kong ), we left our jobs and homes in 2018 and started traveling full time from Canada to Argentina in our self-converted camper van since end of May 2019. “Asobo” means “Let’s play” in Japanese. We named our site “Asobolife” because the life is always uncertain and we live only once so it’s important to always keep positive, playful mind and enjoy the moment you are in the present. We also want to use this website to share our road trip and van building experiences to inspire our readers. We hope you enjoy!

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