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Camper Van Leisure Batteries: A Practical Guide

Camper van leisure batteries are essential to power all the electrical devices in your van. If you plan on having a fan, fridge, lights, or outlets for charging, you will need batteries to power them. 

Theoretically, you could connect all your devices to your vehicle starter battery. However, we do not recommend you do this. Starter batteries are not made to supply continuous power over long periods. If you were to connect your electrical devices to the starter battery, it would quickly drain, and its lifespan would shorten drastically.

That is why most camper vans have a secondary battery in the back dedicated to providing power to the living space. These are often called “leisure” or “auxiliary” batteries. 

This post will guide you through the battery selection process so that you will choose the correct leisure battery that fits your van life requirements. At the end of this post, we show you how to install this battery in your camper van.

What to Consider Before Buying a Leisure Battery

It would help if you answered several questions before buying a leisure battery. Below, we list three of the most important considerations before finalizing your battery solution.

Budget

Like everything in this world, batteries come in a wide range of price points. Older technology batteries, like lead-acid and AGM, are cheaper than the newer lithium batteries you can buy online today. Knowing how much your budget allows for battery purchases can help guide your decision about which battery is best for you.

Length of Travel

Batteries have varying lifespans. Generally speaking, the cheaper the battery, the shorter the life span. A cheap battery might work if you only use your van for weekend getaways. But if you intend to live and travel full-time, upgrading to a battery with a longer lifespan may be worth it.

Battery Size

The amount of battery you need depends on the kind of electrical devices you want to power. Someone who wants to operate a water heater, hair dryer, and toaster oven will need considerably more battery power than someone who only intends to power a few lights and charge a smartphone.

AGM Vs. Lithium Batteries (Pros & Cons)

Several battery chemistries exist, such as lead acid, gel, and lithium. We have found that the two types of batteries most conducive to van life are AGM (a type of lead-acid) and lithium batteries. This section compares these two battery technologies and recommends which we prefer.

AGM – The Budget Battery Solution

Compared to lithium batteries, AGMs are considerably cheaper, often half the price. However, the downsides are that they have a significantly shorter life span (~600 charge cycles) and weigh twice as much.

12V 125Ah VMAX lead acid AGM battery
Standard lead acid AGM battery

AGM batteries are suitable for camper vans if budget is a concern and you only plan to travel part-time with your van. Generally, under constant ‘deep-cycle’ use (50% DoD), AGM batteries have a useable life span of 1-2 years. So, AGM batteries can be an excellent financial choice if your travels will be less than this time frame. 

Lithium – The Modern-Day Work Horse

Lithium batteries – formally known as lithium iron phosphate batteries (LiFePO4) – have a higher upfront cost than AGMs. These batteries sell for anywhere between $300 and $900 USD for a standard 12V 100Ah battery. However, lithium batteries have a considerably longer life span (~3000 charge cycles), can be safely discharged to lower levels, and are half the weight. 

Lithium batteries are an excellent choice for camper vans that demand lots of power and plan to travel for longer than two years, which is when a well-maintained AGM would need to be replaced. At that point, most lithium batteries surpass AGMs as the cheaper option when factoring in cost per charge cycle.

Head-to-Head Comparison

We reviewed 10 AGM and lithium batteries and took the averages of all the information to present side by side for easier comparison.

Average AGMAverage Lithium
Avg. Cost$170$280
Avg. Charge Cycles6003,500
Cost / Cycle$0.28$0.08
Lifespan1.6 years9.6 years
Avg. Weight60.4 lbs (27kg)25.1 lbs (11.4kg)
Depth of Discharge50%80%
Best for:Extreme budget

Short-term/weekend

Travel < 2 years
Extreme budget

Short-term/weekend

Travel < 2 years

From the table above, you can see that, on average, the cost of owning an AGM ($170) is significantly lower than that of a lithium battery ($280). However, when factoring in lifespan, lithium batteries become the cheaper option on a ‘cost per charge cycle’ evaluation ($0.08 vs. $0.28 per cycle).

Our Battery Type Recommendation

Due to their low cost over the long run, we recommend using lithium batteries. The AGM’s lower-rated charge cycles and sensitivities to deeper discharges are unsuitable for long-term camper van living and travel.

Unlike AGMs, Lithium batteries have substantial resale value due to their longer lifespans. Though you pay more for lithium batteries upfront, you can recoup much of that money if/when you decide to sell your camper.

We have been using lithium batteries in our van for over four years of continuous travel and have had zero problems with their ability to keep up with our power demands.

Best Batteries for Van Life (3 Recommendations)

Li Time lithium battery and Redodo Mini lithium battery sitting side-by-side

We recommend three lithium batteries that we think are well-suited for van life. Two of these batteries are budget lithiums that we reviewed and are sold at a great price point. The third battery is a premium lithium battery we have used for over four years on our travels. 

Li Time “TM” Battery

If we could build another camper van, we would use Li Time’s TM lithium battery. The battery has a robust battery management system (BMS) that protects the battery from over-discharging and overheating and stops the charging process when temperatures are below freezing. 

Best Budget LiFePO4
Li Time | Lithium Battery (100Ah)

Our top lithium battery recommendation! The Li Time "TM" packs a serious punch in a compact enclosure. Wide-ranging BMS with low-temperature protection. And superior shock resistance.

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This is Li Time’s Trolling Motor branded battery; this means that this particular battery has superior shock resistance and better withstands the impact of continuous motion and vibration.

Redodo “Mini” Battery

The Redodo Mini is one of today’s most affordable and lightweight lithium batteries. It also has a capable BMS that protects the lithium cells during charging and discharging. However, the Mini does not have the low-temperature protection that the Li Time TM battery has, which may or may not be necessary depending on your travel plans.

Great Value Pick
Redodo Mini Lithium Battery (100Ah)

Lithium batteries outperform standard AGM batteries in virtually every category. The 12V Redodo battery is a great option (at a fantastic price) to 'go lithium' without breaking the bank.

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We recommend the Redodo Mini for those that can afford to upgrade to a lithium battery but are still on a tight van conversion budget.

Unsure of which battery to choose? For a side-by-side comparison of these two batteries, read our Li Time vs. Redodo review.

Battle Born Battery

We have used Battle Born batteries in our van for over four years and love the Battle Born brand. They are considered premium lithium batteries and come at a premium price, roughly three times the cost of the batteries we recommended above. If you believe in the phrase “you get what you pay for,” then Battle Born batteries are for you.

Premium Pick
Battle Born Lithium Battery (100Ah)

We've used these Battle Born batteries for 4+ years in our camper and have kept up with our power needs the entire time. This is a premium battery that comes at a premium price, however.

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However, if you want our opinion, we recommend the Li Time battery above. It’s almost 1/3 the price of a Battle Born and comes with similar features, like the low-temperature cutoff protection. Even if a Li Time battery were to last half the time of a Battle Born, you’d still come out ahead in value.

How To Calculate Your Battery Size

After choosing your van’s battery (type and brand), you will next want to calculate how much battery you will need. Most individual leisure batteries are rated explicitly for 12.8V and 100Ah. That is 1280 Watt-hours (Wh) of power. The three batteries we recommended above are all rated for 1280Wh.

Just because a single battery is rated for 1280Ah, however, does not mean this is the size your camper van requires. In many cases, camper vans will require MORE than 1280Wh of power to run all the electronic devices in the van. Based on our calculations, we opted for three batteries for a combined 3840Wh of total power.

Man sitting behind three Battle Born camper van leisure batteries inside a Ford Transit camper van
Three Battle Born batteries in our van

Prevent Dead Batteries: Batteries die prematurely when overused and over-discharged, often when a van has too small a battery bank. With adequately sized batteries, you will extend the lifespan of your batteries and maximize their value.

We provide two options to help you determine what size battery bank you will need for your camper van:

  1. Simple table: Easy & quick to use and accurate
  2. DIY spreadsheet: For those who enjoy getting a more nuanced answer

1. Simple Table

From our experience, most camper vans can be lumped into three categories: light, moderate, and heavy electrical demands. The table below draws distinctions between these three categories. Identify the electrical devices you intend to use in your camper van to determine what size battery you need.

Note: The battery size recommendation table below is for lithium (LiFePO4) batteries operating at 12V. If using AGM, double the table’s recommended battery size. If installing 24V lithium batteries, divide the table’s recommendation in half.

100Ah Battery
(Light)
200Ah Battery
(Medium)
300-400Ah Battery
(Heavy)
Pairs with:

LED lights
Vent fan
Phone
Laptop
Pairs with:

12V fridge
Diesel heater
Electric kettle
2000W inverter
Pairs with:

Induction cooktop
Electric boiler
Small heater
3000W Inverter

2. DIY Spreadsheet

Download our battery calculator spreadsheet to get a more accurate battery size recommendation. It is a Google Spreadsheet document and is free to use.

To use the calculator effectively, you will need to know:

  • All the electrical devices you plan to have
  • How many units of each device will there be (i.e., one laptop or six LED lights)
  • How many Watts each device will require to operate
Battery calculator spreadsheet displaying battery size recommendations for AGM and lithium batteries
Final battery size recommendations for AGM and lithium batteries

And that’s it. Our battery calculator will then recommend how much battery power your camper van will require, whether you choose AGM or lithium, to adequately power all your devices daily.

For more detailed, step-by-step instructions, check out our battery calculator post.

Calculation Caveat: Calculating battery size is not an exact science, and every website will do it slightly differently. But in our four years of experience, we believe our calculator appropriately considers changes in seasonal weather and diverse ranges of camping styles. (This assumes you also use our solar calculator to recharge your batteries adequately!)

How To Charge Camper Van Batteries

There are four common ways to charge the leisure batteries, and you are not required to choose only one method. Many camper vans often select two or even three battery charging solutions. The four charging methods are:

  1. Solar panels
  2. DC-DC charger (from vehicle alternator)
  3. Shore power
  4. Generator (gas/propane)

Below, we briefly discuss each charging method, review its pros and cons, and give product recommendations. For more in-depth information, check out our battery charging solutions post.

Charging With Solar Power

Solar panels are one of the most popular ways to charge leisure batteries in a camper van and are one of the only environmentally sustainable ways to generate power. It is also a passive charging process, meaning as long as the solar panels receive sunlight, your batteries will receive a charge. There is no other work on your end that you are required to do.

BougeRV | 200W Solar Panel

We've spoken with BougeRV reps and came away impressed with their customer service. They also make excellent quality, highly efficient '9BB' solar panels. Consider installing a larger 200W panel instead of multiple smaller panels.

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There are two downsides to using solar panels. The first one is that solar panels are not particularly efficient at converting sunlight into power. Because of this, charging via solar panels is one of the slowest ways to put power back into your batteries. The second downside is that the solar panels require clear and direct sunlight. Extended periods of cloudy and rainy days, or parking in the shade, means you won’t be able to rely on solar panels to recharge the batteries each day adequately. But! This is precisely why we mentioned earlier that you don’t have to pick only one way of recharging your batteries.

Undersized Solar System: Regrettably, many camper vans do not adequately install enough solar watts to recharge their batteries each day. In most cases, you will need MORE than 100W of solar.

How Much Solar Do You Need?

The more solar watts you have, the faster the leisure batteries will recharge. How much solar your camper van needs depends entirely on your situation. Refer to our solar size calculator to help you determine your solar needs.

Note: This solar calculator is intended to be used alongside our battery calculator and won’t be accurate by itself.

Charging From A DC-DC Charger

By connecting the leisure batteries to a DC-DC charger, you can charge the batteries while driving your van. This is possible because the DC-DC charger will also be wired to your vehicle’s starter battery, which will receive a charge from the alternator while the engine is running.

It can get a bit technical, but know that as long as your engine runs, your leisure batteries will receive a charge.

Victron | DC-DC Charger (30A)

Charge your leisure batteries quickly with Victron's 30A DC-DC charger (up to 360W). Works great for both lithium and AGM batteries. But the highlight is the charger's Bluetooth connectivity, which pairs with Victron's UX-friendly smartphone app.

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Note: If you elect to use AGM batteries, you can use a cheaper split charge relay, but lithium batteries will require a DC-DC charger.

Unlike solar panels, the upside of having a DC-DC charger is that you aren’t constrained by weather and sunlight. You can charge your leisure batteries as long as you have gas in the tank and a functioning engine.

The downside is that DC-DC chargers only realistically work when driving long distances (i.e., over an hour). Short 5-minute drives to the nearby grocery store won’t be enough to charge the batteries if this is your only charging solution.

Our take? We highly recommend pairing a DC-DC charger with solar panels to provide a comprehensive battery charging solution. When solar panels become unreliable due to weather or shade, DC chargers can pick up the battery charging slack. And vice versa.

Charging From Shore Power

You can also charge leisure batteries by connecting them to shore power. Shore power is any standard public electrical socket. These sockets can be located at campsites, truck stops, or even in the garage at home. To utilize shore power charging, you will need a dedicated battery charger or an inverter/charger combo unit.

 
 
Description:

Simple dedicated battery charger to recharge batteries from shore power.

Description:

Powerful 2000W inverter/charger combo unit. Converters 12V DC power to 110V AC and vise versa. We use this unit in our camper van.

Description:

Simple dedicated battery charger to recharge batteries from shore power.

Description:

Powerful 2000W inverter/charger combo unit. Converters 12V DC power to 110V AC and vise versa. We use this unit in our camper van.

The pros of shore power charging are that, when plugged in, you can access limitless power to recharge your leisure batteries. You are not dependent on sunlight or driving to power the batteries. It is the most convenient charging method.

The con of shore power is that it can be challenging to locate a shore power socket if you are unwilling to pay for a pricey campsite. And since we often choose to free camp to save money, shore power charging is our least popular charging method.

Charging From A Generator

The last and least popular charging method is to connect the batteries to a generator. Essentially, you are creating your own shore power socket with a generator. As a result, you will still need a battery charger unit, like the two we recommended in the section above, to charge the leisure batteries from the generator.

Gasoline power generator for camper vans

The upside of carrying a generator is that you can access dedicated power, even when boondocking far out in nature. You will have power if you have gas or propane in the tank.

In our opinion, however, the downsides are substantial. Not only are generators bulky and heavy, but they also require fuel and are loud when in operation. We wouldn’t feel comfortable using a generator in a public setting with other campers around.

How To Maximize The Lifespan Of A Leisure Battery

Leisure battery lifespan is expressed in terms of “charge cycles,” which is the number of complete charges and discharges a battery can undergo before it is deemed unusable.

However, relying on a battery’s rated number of charge cycles is tricky. A battery may be rated for 600 charge cycles, but this does not guarantee that the battery will provide 600 cycles of power in real-life scenarios. If a battery is poorly treated, its lifespan may only be half its rated charge cycle. Conversely, treating your battery well can extend its life beyond the rated charge cycle.

So, what can you do to maximize a battery’s lifespan (i.e., charge cycles)?

Generally speaking, the greater a battery is discharged, the shorter its lifespan. But a more in-depth answer depends on whether you use AGM or lithium batteries.

Maximizing Lifespan Of Lithium Batteries

Below is a helpful chart indicating the relationship between how a lithium battery is charged/discharged and its age (capacity to hold a charge). Each color below represents a lithium battery charged and discharged to different levels.

The key takeaways from this study are:

  • Do not charge (and keep) a lithium battery at 100% charge. Doing so significantly shortens the battery’s lifespan.
  • Keeping a maximum charge of 75% is ideal.
  • Try to discharge the battery as little as possible below 75%. Down to only 65% is ideal. (But keeping it to above 45% charge is likely more realistic.)

Our Lithium Experience: To maximize the lifespan of our lithium batteries, we are constantly monitoring their state of charge. We also continually turn our solar charge controller and DC-DC charger on and off to keep our batteries within the 45%-75% charge range.

Maximizing The Lifespan Of AGM Batteries

Unlike lithium batteries, AGMs like to be charged to (and kept at) 100%. But the deeper AGMs are discharged past 100%, the shorter their lifespans are. The chart below shows how a greater depth-of-discharge (DoD) of an AGM battery reduces its rated number of charge cycles.

AGM lifecycle chart
Source: Renogy

The key takeaways of the above graph are:

  • Try to discharge an AGM battery as shallowly as possible.
  • If only discharging down to 50% each time, expect an AGM battery to provide ~650 charge cycles.

How Do You Determine a Battery’s State of Charge (SoC)?

Unlike a cellphone or laptop that shows you exactly what percentage the battery is charged, leisure batteries don’t display this information. Then how are you supposed to know what percentage of the battery is charged? Two methods exist to determine a leisure battery’s state of charge (SoC).

  1. Multimeter (the budget way)
  2. Battery monitor (our pick)

We describe both these methods below and their pros and cons.

1. Multimeter (The Budget Way)

A digital multimeter is a multipurpose tool used to diagnose electrical issues. One of the many features of the multimeter is to measure a battery’s voltage. Switch the dial to the appropriate readout location, then connect the red and black test leads to the appropriate battery terminals. The multimeter should then display the battery’s voltage.

Digital multimeter displaying voltage of 9V battery
Example of multimeter showing the voltage of 9V battery

As a battery is discharged, its voltage decreases. So, by evaluating the battery’s instantaneous voltage, you can determine its percentage charge. Refer to the chart below to see the relationship between a battery’s voltage and its state of charge.

Two tables displaying voltage and state of charge information for lithium and AGM batteries

We color-coded the cells to represent the following information:

  • Green Cells: Maintain battery voltage in this zone
  • Yellow Cells: Try not to enter these zones too frequently
  • Red Cells: Avoid these zones as much as possible

The benefit of using a multimeter to measure the battery’s charge percentage is that this tool is cheap and easy to use. The downside, however, is that using this tool is labor-intensive. You must constantly take the tool out, unpack it, and touch the leads to the battery terminals.

2. Battery Monitor (Our Pick)

Battery monitors are our preferred method for determining a battery’s state of charge. These monitors typically come with two components: a shunt connected to the battery and a display unit. Below, we recommend a budget and higher-end monitor. The latter has Bluetooth capability and can pair with a smartphone to display instantaneous battery information directly on your phone.

For Specific Install Info: Read our battery monitor installation guide, including recommended materials and tools.

The benefit of using a battery monitor is that, by using the display, checking the battery’s state of charge becomes a quick and easy endeavor. Most battery monitors also display other useful information, such as instantaneous current flows into and out of the battery.

The drawbacks of using a battery monitor are that it will require some installation and is more costly than a simple multimeter.

How To Install A Leisure Battery In A Camper Van

This last chapter will discuss installing a leisure battery in a camper van. We separate this into three sections:

  1. Tying down the batteries
  2. Wiring multiple batteries together
  3. Connecting batteries to the bus bars

1. Tying Down The Batteries

When installing batteries in a camper van, you must ensure that the batteries are sufficiently tied down so they won’t vibrate and move while your van is in motion. This can be challenging, especially considering how heavy leisure batteries are (~25-60 lbs each).

Some camper vans use ratchet straps to tie down their batteries. This can be difficult, however, if you don’t have sufficient anchor points. You may also need multiple ratchet straps to prevent horizontal and vertical battery movement.

Our solution was to attach our three batteries to small plywood boards via heavy-duty 3M VHB double-sided tape.

Strongest Hold
3M VHB Mounting Tape (0.5" Width)

An incredibly strong bonding agent. We use VHB tape to affix both our solar panels and batteries to their respective surfaces.

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Once completed, we fixed the plywood boards to our sub-floor with large wood screws. In this way, we can limit the movement of our batteries. Refer to the below image to see how we did this.

Three pieces of plywood on the floor with 3M VHB tape placed on top
Batteries placed on plywood boards via 3M VHB tape

2. Wiring Multiple Batteries Together

If you have multiple batteries, you must decide whether to wire the batteries together in “parallel” or “series.” Below are two diagrams illustrating the physical differences between parallel and series battery wiring.

Note: Wiring batteries in parallel combines the Amp-hours (Ah) but keeps the voltage constant. Series wiring keeps the Ah constant but combines the voltage.

Three Battle Born camper van leisure batteries wired in series
Three batteries connected in series
Three Battle Born camper van leisure batteries connected in parallel
Three batteries connected in parallel

If you are building a 12V system (which you most likely SHOULD be doing) and are using 12V batteries, your only choice is to wire your batteries together in parallel, not in series.

What Wire Size To Use? Read our battery cable size post to help you determine what wire gauge you need to connect your batteries.

Life Pro Tip: To simplify things, you can skip this step by buying 200Ah and 300Ah batteries. This way, you do not have to wire two or three 100Ah batteries together. We would do this instead if we were to build another camper van.

Should your batteries operate at 12V or 24V? Read our 12V vs. 24V battery post to learn more about each wiring type’s pros and cons.

3. Connecting Leisure Batteries To The Bus Bars

Connecting the leisure batteries to the bus bars is the foundational step of any camper van electrical system. Once completed, you can wire all future downstream devices (i.e., 12V panel, inverter, solar charge controller, & DC-DC charger) to these bus bars, and they will automatically be connected to the batteries.

Follow the diagram below to learn how – and what materials you will need – to complete this wiring process.

Wiring diagram for camper vans connecting leisure batteries to bus bars. Includes fuses, battery switch, and battery monitor.
Wiring 12V batteries to bus bars

List Of Materials

Below is a comprehensive list of materials to complete this section.

 
 
 
 
 
 
 
Description:

Recommended size for 12V system & inverters up to 2000W. (YouTube review)

Description:

Crimps onto 2/0 wire. Fits on M10 terminal posts.

Description:

Crimps onto 2/0 wire. Fits on M8 terminal posts.

Description:

Protects wire from overheating. (Youtube Review)

Description:

Disconnects battery from electrical system. (YouTube Review)

Description:

Power distribution & collection

Description:

Displays battery state-of-charge percentage.

Description:

Recommended size for 12V system & inverters up to 2000W. (YouTube review)

Description:

Crimps onto 2/0 wire. Fits on M10 terminal posts.

Description:

Crimps onto 2/0 wire. Fits on M8 terminal posts.

Description:

Protects wire from overheating. (Youtube Review)

Description:

Disconnects battery from electrical system. (YouTube Review)

Description:

Power distribution & collection

Description:

Displays battery state-of-charge percentage.

Ready for more info? For a more in-depth electrical system installation tutorial, read our camper van 12V installation guide.

Our electrical diagrams PDF is a fantastic resource if you want to build an electric system with the least effort and in the quickest amount of time. There are over 35 pages of detailed content, and this PDF is free to download.

Conclusion

There is a tremendous amount of information regarding camper van leisure batteries, and it can often feel like a deep rabbit hole once you start the research process. We hope this post provides only the information that is necessary to know so that you can build the best battery setup for your camper van conversion.

When you are ready, we encourage you to visit our complete electrical installation guide for camper vans, which provides step-by-step installation guidance with tips and recommended material lists.

Please let us know in the comments section below if you have any additional questions or uncertainties.

Happy building!

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