JuiceBox Rescue: Freeing Tethered EV Chargers From Corporate Overlords

August 27, 2025 by Maya Posch 30 Comments

The JuiceBox charger in its natural environment. (Credit: Nathan Matias)

Having a charger installed at home for your electric car is very convenient, not only for the obvious home charging, but also for having scheduling and other features built-in. Sadly, like with so many devices today, these tend to be tethered to a remote service managed by the manufacturer. In the case of the JuiceBox charger that [Nathan Matias] and many of his neighbors bought into years ago, back then it and the associated JuiceNet service was still part of a quirky startup. After the startup got snapped up by a large company, things got so bad that [Nathan] and others saw themselves required to find a way to untether their EV chargers.

The drama began back in October of last year, when the North American branch of the parent company – Enel X Way – announced that it’d shutdown operations. After backlash, the online functionality was kept alive while a buyer was sought. That’s when [Nathan] and other JuiceBox owners got an email informing them that the online service would be shutdown, severely crippling their EV chargers.

Ultimately both a software and hardware solution was developed, the former being the JuicePass Proxy project which keeps the original hardware and associated app working. The other solution is a complete brain transplant, created by the folk over at OpenEVSE, which enables interoperability with e.g. Home Assistant through standard protocols like MQTT.

Stories like these make one wonder how much of this online functionality is actually required, and how much of it just a way for manufacturers to get consumers to install a terminal in their homes for online subscription services.

Tesla’s Plug Moves Another Step Closer To Dominance

December 21, 2023 by Navarre Bartz 46 Comments

Charging an EV currently means making sure you find a station with the right plug. SAE International has now published what could be the end to the mishmash of standards in North America with the J3400 North American Charging Standard.

The SAE J3400TM North American Charging Standard (NACS) Electric Vehicle Coupler Technical Information Report (TIR), which just rolls off the tongue, details the standard formerly only available on Tesla vehicles. We previously talked about the avalanche of support from other automakers this year for the connector, and now that the independent SAE standard has come through, the only major holdout is Stellantis.

Among the advantages of the NACS standard over the Combined Charging System (CCS) or CHAdeMO is a smaller number of conductors given the plug’s ability to carry DC or AC over the same wires. Another benefit is the standard using 277 V which means that three separate Level 2 chargers can be placed on a single 3-phase commercial line with no additional step down required. Street parkers can also rejoice, as the standard includes provisions for lampost-based charger installations with a charge receptacle plug instead of the attached cable required by J1772 which leads to maintenance, clutter, and ADA concerns.

Now that J3400/NACS is no longer under the purview of a single company, the Federal Highway Administration has announced that it will be looking into amending the requirements for federal charger installation subsidies. Current rules require CCS plugs be part of the installation to qualify for funds from the Bipartisan Infrastructure Bill.

If you want to see how to spice up charging an EV at home, how about this charging robot or maybe try fast charging an e-bike from an electric car plug?

A silver front loader cargo bike sits in a parking lot in front of an electric vehicle charger. A cable runs from the charger to the bike.

Fast Charging A Cargo Bike From An Electric Car Charger

September 18, 2023 by Navarre Bartz 15 Comments

Fast charging is all the rage with new electric cars touting faster and faster times to full, but other EVs like ebikes and scooters are often left out of the fun with exceedingly slow charging times. [eprotiva] wanted to change this, so he rigged up a fast charging solution for his cargo bike.

Level 2 electric vehicle chargers typically output power at 7 kW with the idea you will fill up your electric car overnight, but when converted down to 60 V DC for a DJI Agras T10 battery, [eprotiva] is able to charge from 20% to 100% capacity in as little as 7 minutes. He originally picked this setup for maxing the regen capability of the bike, but with the high current capability, he found it had the added bonus of fast charging.

The setup uses a Tesla (NACS) plug since they are the most plentiful destination charger, but an adapter allows him to also connect to a J1772 Type 1 connector. The EV charging cable is converted to a standard 240 V computer cable which feeds power to a drone charger. This charger can be set to “fast charge” and then feeds into the battery unit. As an added bonus, many chargers that do cost money don’t start charging until after the first five minutes, so the bike is even cheaper to power than you’d expect.

For some reason, you can watch him do this on TikTok too.

If you too want to join the Personal EV Revolution, be sure to checkout how to choose the right battery for your vehicle and a short history of the Segway.

An Unexpected Upset In EV Charging Standards

June 21, 2023 by Navarre Bartz 52 Comments

Last November, Tesla open-sourced parts of its charging infrastructure, not-so-humbly unveiling it as the North American Charging Standard (NACS). It’s finally taking off with a number of manufacturers signing on.

Companies launching “standards” based on their previously proprietary technology in opposition to an established alternative usually leads to standards proliferation. However, with recent announcements from Ford, GM, and Rivian that they would begin supporting NACS in their vehicles, it seems a new dominant standard is supplanting CCS (and the all-but-dead CHAdeMO) in North America.

As Tesla already has the most extensive charging network on the continent and has begun opening it up for other EVs, it makes sense that other marques would want to support NACS, if nothing else to satiate customer demand for a dead-simple charging experience. Dongles are annoying enough for plugging in an external monitor. Having to mess with one while handling high-power electrical connections is less than ideal, to say the least.

If you want to add NACS to your own EV project, the standard is here. We’ve discussed some of the different standards before as well as work toward wirelessly charging EVs (besides the inductive charger on the EV1). It certainly seems like the time to get in on the ground floor of an EV charging empire with an army of Charglas.

A red Tesla Model 3 converted into a pickup truck with a black lumber rack extending over the roof of the cab sits in a grey garage. A black and silver charging robot is approaching its charging port from the right side attached to a black cable. The charging bot is mostly a series of tubes attached to a wheeled platform and the charging connector itself is attached to a linear actuator to insert the charging device.

Truckla Gets An Open Source Charging Buddy

April 11, 2023 by Navarre Bartz 11 Comments

More than three years have passed since Tesla announced its Cybertruck, and while not a one has been delivered, the first Tesla truck, Truckla, has kept on truckin’. [Simone Giertz] just posted an update of what Truckla has been up to since it was built.

[Giertz] and friend’s DIT (do-it-together) truck was something of an internet sensation when it was revealed several months before the official Tesla Cybertruck. As with many of our own projects, while it was technically done, it still had some rough edges that kept it from being truly finished, like a lack of proper waterproofing or a tailgate that didn’t fold.

Deciding enough was enough, [Giertz] brought Truckla to [Marcos Ramirez] and [Ross Huber] to fix the waterproofing and broken tailgate while she went to [Viam Labs] to build Chargla, an Open Source charging bot for Truckla. The charging bot uses a linear actuator on a rover platform to dock with the charging port and is guided by a computer vision system. Two Raspberry Pis power handle the processing for the operation. We’re anxious to see what’s next in [Giertz]’s quest of “picking up the broken promises of the car world.”

If you want to see some more EV charger hacks, check out this Arduino-Based charger and the J1772 Hydra.

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The J1772 Hydra Helps You Charge Two EVs At Once

December 2, 2022 by Lewin Day 20 Comments

There are plenty of electric vehicle (EV) chargers out there that are underutilized. This is particularly common where older EVs are involved, where the cars may only be able to charge at a few kW despite the charger being capable of delivering more. [Nick Sayer] regularly found 6.6 kW chargers being used by vehicles that could only draw down 3.3 kW at his work. Thus, he built the J1772 Hydra as a nifty double-adapter to charge two cars at once.

The Hydra comes in two versions. One is a “splitter,” which is designed to be plugged into an existing J1772 AC charger. The other is a version designed for permanent installation to an AC power supply as an EV charger in its own right. Either way, both versions of the Hydra work the same way. In “shared” mode, the Hydra splits the available AC power equally between both cars connected to the charger. When one completes, the other gets full power. Alternatively, it can be set up in “sequential” mode, allowing one car to first charge, then the other. This is great when you have two cars to charge overnight and don’t want to wake up to shift the plugs around.

It’s a neat hack that could be useful if you’re running older EVs that rely on slower AC charging. We’ve seen other DIY EV chargers before, too. Expect hacking in these areas to become more commonplace as EVs grow in popularity.

EV Chargers Could Be A Serious Target For Hackers

November 28, 2022 by Lewin Day 56 Comments

Computers! They’re in everything these days. Everything from thermostats to fridges and even window blinds are now on the Internet, and that makes them all ripe for hacking.

Electric vehicle chargers are becoming a part of regular life. They too are connected devices, and thus pose a security risk if not designed and maintained properly. As with so many other devices on the Internet of Things, the truth is anything but.

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