Since you know how much battery capacity you need, let’s figure out which batteries to buy. There are two main types: Lithium and AGM. The decision is often brought down to two main points: budget and battery life.

AGM batteries are cheaper, heavier, and can only be discharged to half capacity before sustaining damage. Lithium batteries are lighter, more expensive, and can be depleted nearly 100% of capacity safely.

You can buy multiple of the same batteries, wire them in parallel, and add the capacities together. You do not need to buy one massive 400Ah battery. A lot of conversion vans have multiple 100Ah batteries.

Remember that when you connect multiple batteries in series, you are adding the voltages of each battery together while keeping the total amp-hours the same.

Instead, wiring batteries in parallel keeps the voltage unchanged while adding together the amp hours. Most deep-cycle batteries are 12V and you want to build a 12V system while expanding the battery bank size. Therefore, wiring in parallel is the ideal option for most vanlife cases.

An MPPT Solar Charge Controller is needed to convert the voltage of your solar system. It delivers the power to your batteries at an optimal voltage that is safe for them to charge at.

Because MPPT Charge Controllers are able to deliver a higher percentage of power to batteries, they are more efficient than other charge controllers. They do this by simultaneously increasing amperage while decreasing the voltage of the current.

Solar controllers all have numbers in the name. These numbers represent the maximum voltage and maximum current they are rated for. For example, Victron MPPT Solar Controller (100/50) has a maximum voltage of 100V or 50A.

This number is unique to your specific solar setup. To determine what is safe for your application, you need to know how much solar power you need, and how the panels are wired.

The principle is the same as with batteries. If your panels are wired in parallel, you need to add up their amperage. If your panels are wired in series, you need to add up their voltage. The resulting number should not exceed the rated voltage and amperage of the MPPT controller.

Most vanlifers find it convenient to be able to plug in and charge their house batteries when the option is available. To do this, your van's electrical system will need shore power. This is achieved by installing a converter charger or an inverter charger.

Battery chargers simply convert 120V AC power to 12V DC to charge your batteries. In addition to charging your batteries, the converter also distributes converted DC power to other RV components.

Inverter chargers have the additional advantage of also providing AC power to your appliances. This makes them generally the preferred option. Installing one inverter charger is easier and takes up less space than having an inverter and a converter separately.

The purpose of a DC/DC charger is to charge your batteries while you drive. The DC/DC charger is safer than a standard battery isolation manager (Li-BIM) as it is able to control the current and voltage going into your motorhome batteries. This is a great addition to any van electrical plan, especially to help you get through the winter when there’s less sunlight!

A DC Fuse Panel serves as the distribution point for all of your DC appliances. Appliances like roof fans, lights, fridge, heater, etc. Basically, all the vanlife essentials that ensure a comfortable life on the road. A good way to think about DC devices is they don’t get plugged into an outlet.

In addition to the wide availability of 12V devices, a 12-volt system is also easy to install. Your campervan is likely to have a native 12-volt system onboard. This means that you’ll need relatively few modifications to power all your 12-volt appliances.

Finally, 12V systems are generally safe. Electricity lower than 50 volts is classified as safe for human contact. Nonetheless, you should always be cautious when working with any type of live electrical system. Always wear appropriate protective equipment.

If you plan to charge laptops, power a blender, or run any other standard household device, it’s necessary to install an inverter. It will convert the 12V from your batteries to a usable 120V for AC-powered devices.

The two types of inverters are True Sine Wave (TSW) and Modified Sine Wave (MSW). TSW is often the better choice, as it delivers a more consistent signal when compared to the choppier modified sine wave signal.

The three most common inverter sizes are 1000, 2000, and 3000 watts, like the Victron Energy MultiPlus Compact Inverter. To determine which size is best for you, use the calculations we did previously to find the maximum current you will be drawing from your van at any one time.

A fuse is a thin strip of metal that melts when there is an overcurrent. This melting opens the circuit thus cutting the power supply to the device on the other end.

Fuses are an essential part of any campervan electrical system and the most well-known way to protect an electrical circuit.

To choose the proper fuse, start by checking the device on the circuit. That is the best recommendation to follow. If that is not present, use the following:

We suggest using two layers of additional protection on your main wires.

A wire sheath is an expandable braided sleeve that adds a layer of resistance to rubbing and cutting, or “abrasion resistant”. This is ideal for wires that pass through wall cavities and will protect the wire from sharp edges.

A wire conduit is essentially plastic tubing used for wires that need to be run externally, or under the base of the camper. A conduit will add another layer of protection from cuts and rubbing, but also protects from debris and moisture.

Determining the current load of an appliance is as easy as checking the manual or spec sheet. You are simply looking for the amperage of the appliance. Many appliances might even have amperage on the label.

In case you are only provided with wattage, you can still easily calculate the current. Simply divide the wattage of the appliance by the voltage of your system.

This is as simple and straightforward as it sounds. Measure the path the wire will take from the batteries to where the appliance is going and then back to the batteries.

When approximating this number, always best to approximate too high than too low. And don’t forget to get the distance going in both directions.

As power travels from the power source to the load, it encounters a small amount of resistance. This causes a slight drop in voltage.

Certain appliances can tolerate more or less voltage drop than others: we call these critical drop and non-critical voltage drop appliances. Critical drop appliances can only tolerate a 3% voltage drop. Non-critical voltage drop can handle up to a 10% voltage drop.

Critical voltage drop wires include those connecting the batteries, the inverter, MPPT charge controllers, and your DC fuse panel – basically the backbone of your electrical system.

Non-critical voltage drop wires are those going to your individual point-of-use appliances that are generally more tolerant to fluctuations in voltage (note: please check with your appliance manufacturer to be sure).