We tested the Juice Booster 3 air: the smart wallbox you can use at home... or keep in the boot at all times to charge your electric car

Switching to electric mobility couldn’t be easier with the offer from Juice Technology, a specialist in charging solutions for electric cars. I’m talking about the Juice Booster 3 air, the portable charging station from the Swiss company which, thanks to the Juice Connector system with up to 30 possible adapters and its compact size, you can use as a wallbox to charge your electric car at home, or as a portable charger to recharge practically anywhere you have a power socket, whether domestic or industrial.

In fact, there is no comparable solution on the market to the one the Juice Booster 3 air offers, which, as I was saying, can work as a wallbox and as a portable charger, as well as serving as a charging cable, although it has many other functions that I’ll tell you about shortly. Compared to the Juice Booster 2, which remains in the Swiss brand’s catalogue, the Booster 3 air limits the maximum charging power from 22 kW to 11 kW, more than enough for most uses. In return, it is much lighter and more compact, which is appreciated when transporting it. And it adds connectivity via Wi-Fi or Bluetooth with the j+ pilot app for mobile devices, with a host of functions. Let’s look at it in more detail.

The main features of the Juice Booster 3 air

As a wallbox for use at home or as a mobile charging station to take anywhere, the Juice Booster 3 air allows charging with single-phase or three-phase current from 6 to 16 amps, at a maximum power of 11 kW. Surprising, especially considering its size: a cylinder just over 5 cm in diameter and about 22 cm long, weighing barely 700 grams, not counting the cable.

Using the Schuko-type adapter included in the basic kit, the Juice Booster 3 lets you charge an electric car from any domestic socket. And with the Type 2 adapter, also included in the kit, it can be used as a charging cable to recharge at any public charging point. This plug has two special features: a button that allows you to conveniently adjust the current intensity during the 30 seconds after connecting to the charging point – something that can also be done from a button on the charger itself – and which at the same time serves to stop charging and unlock the plug – provided the car allows it – and an integrated RFID reader that allows you to unlock the charging process with two cards included in the kit.

Connectivity is another interesting feature of the Juice Booster 3 air: via Wi-Fi or Bluetooth it can connect to the free j+ pilot app, without needing a GSM connection or a mobile SIM card. This not only allows wireless updates of the device, but it is also possible to control the charging process remotely from the smartphone and consult consumption reports, for example, by assigning a tariff to each charging session, which is stored in the app’s history.

Another function that a private user will hardly take advantage of, but which may be interesting in communities or businesses using several chargers, is that it also allows configuring a cloud-based dynamic charging management. It supports connecting up to 10 devices to each other, balancing the load and distributing power so as not to overload the grid.

A wallbox at home with no installation needed: plug in and go

If what you need is simply a charger to charge your electric or plug-in hybrid car at home with a low charging power – around 3 kW – and you don’t plan to increase your contracted power or install a wallbox, there are many chargers on the market that can fulfil this function for a much lower outlay: around 200 euros, or even less. However, for using it mainly at home as an alternative to a wallbox without going through an installation process, and also using it when needed as a mobile charging station you can take anywhere, the Juice Booster 3 air has many advantages.

To begin with, it is fully “plug and play”; that is, it comes fully configured and you only need to connect the device to the power socket with the appropriate adapter. The brand sells a wall bracket – it costs around 75 euros – that allows you to mount it to use as a “fixed” wallbox, or to take it out directly to carry in the boot when you use it as a mobile charger. Bear in mind, though, that the maximum charging power you will achieve will be limited by the electrical installation itself… and by the power you have contracted.

In this regard, one advantage of the Juice Booster 3 air that I consider key is the safety it offers. It has a built-in fault protection function, so there is no need to install a special circuit breaker, as usually happens with domestic wallbox installations. The device detects up to ten different types of possible faults, such as badly wired sockets, excessive current draw by the vehicle, faults in the grid or in the car itself… The system shows the type of fault on the screen, and if necessary rejects or interrupts charging.

And especially for domestic use, I also think it’s important to point out the temperature protection and control system, which thanks to a sensor built into the Schuko adapter detects if the socket to which we connect the charger overheats. In that case, the device automatically interrupts charging and resumes it up to three times, allowing time for cooling, progressively reducing the charging power.

The Juice Booster 3 air put to the test: many advantages and one drawback

The standard Juice Booster 3 air kit comes in a practical case for carrying it comfortably in the car, which even has Velcro on the underside so it stays fixed to the boot floor. And here comes the main drawback: its high price. This kit includes the charger, an adapter for domestic Schuko sockets, a CEE16 400V adapter for three-phase charging and two RFID cards, at a price of 1,320 euros. To also have the Type 2 adapter you have to go for the EU Traveller Set Plus kit, which adds two more adapters (CEE32 and CEE16 230V and 400V) that you won’t make use of, and the price rises to 1,625 euros. You can also buy the basic kit and add the Type 2 adapter as an individual option, for a price of 172 euros. Extension cables of 5 and 10 metres are also available.

The quality of the carry case, or rather that of its zip, could be better. But the feel of the charger is fantastic. It meets the IP67 specifications for protection against water and dust, so it can also be used safely outdoors. And according to the manufacturer, it is built to withstand even a 3-tonne vehicle driving over it. Honestly, it seems indestructible. And the connection system for the adapters to the charger also makes it clear that we are dealing with a “premium” product.

Getting started with it is very simple. I have been able to test its operation with different electric cars, specifically with a BYD Seal, with a Renault ZOE and with a Seres 5, as well as with several plug-in hybrids, both as a portable charger and as a “wallbox” at home, without any problem. That said, on a conventional domestic Schuko socket, without an adequate electrical installation or a reinforced plug, and with a maximum contracted power of 4.6 kW, don’t expect to charge at more than 2 kWh… the same as with a “cheap” charger. If you buy a Juice Booster 3 air to use at home as a wallbox, my recommendation is to make sure you have a power socket with wiring of the right cross-section, 2.5 mm, so you can charge at 16 amps. And it is highly advisable for the socket to be of the Green-up type. Of course, just as happens if you install a wallbox, you will need to raise your contracted power if your tariff is low, or you won’t take advantage of the Juice Booster 3 air’s charging capabilities. Remember it goes up to 11 kW.

Linking the device to a mobile phone via the app, whether over Wi-Fi or Bluetooth, is very simple, though somewhat slow. It shows data on the charge in progress and lets you change the current intensity the system chooses by default. The intensity can also be changed with a button on the charger itself. This is useful, for example, for reducing the intensity when using the charger on old installations. You will in no case be able to increase the charging current above the value set by the Juice Booster 3 air. The charging amperage is shown on the screen, which can also display alert messages such as overload, excessive heating, possible RCD trip or even a message indicating that no earth connection has been detected. In this case it is possible to select the “Earth Check Off” operating mode, which disables the check of the device’s internal earth conductor.

Juice Booster 3 air – Image gallery