EV Charging Tribulations

Last month (May 2025) I was excited to learn from Hyundai that they planned to ship me a free adapter that would enable my 2023 electric car to use Tesla-style chargers. But I when got to try out the adapter for the first time last week it didn't work. Nothing was wrong with the car, adapter, or charging station - but the situation is more complicated than I thought.

Background on Electric Vehicle (EV) Charging

We're all survivors of various charging-standards wars. We've finally resolved the phone-charging conflict as Apple moved to USB-C and are now enjoying cell-phone peace. For EV charging, it looks like Tesla has won with their "North American Charging System" (NACS) as manufacturers for the US market have abandoned the previously-dominant Combined Charging System (CCS). The Nissan Leaf already lost with the CHAdeMO standard largely unused in the US for new models. But cars last longer than cell phones, so we'll be dealing with the aftermath for a while.

J1772 / CCS on the left, NACS in the middle
CCS adds two more pins below the picture for level 3 charging

Our car is a 2023 Hyundai IONIQ5, which uses a CCS port. Hyundai has changed to a NACS port starting in 2025 models, and is providing adapters to enable CCS-plug cars to connect to NACS plugs. I imagine this is to preserve the value of the used-car fleet so that people can sell their older models and upgrade to a newer Hyundai at some point in the future.

Chargers fall into three categories:

1. Level 1 chargers: Standard 12-amps / 110-volt (12A / 110V) wall outlets, capable of providing up to 1.3 kilowatts (KW). These are the slowest chargers; a full charge for my car is about 70 kilowatt-hours (KWh), so charging would take about three days from 0-100%. We only have a level 1 charger at home: reality is for us that we can normally refill overnight from the 10-12% we take off the batter per day.
2. Level 2 chargers: "Dryer" outlets in houses providing 48A / 240V power, and the chargers are rated up to 80A. In a household environment, they put out 11.5 KW (compared to 1.3 KW at level 1), so they're nearly 10 times faster.
3. Level 3 chargers: These are the direct-current (DC) "fast chargers" that people tend to talk about. They're only necessary on road trips to quickly refill a battery and can put out 100s of KW. Tesla's "Supercharger" network is an example of level 3 charging, and the Hyundai press release makes a point that the adapter enables access to the Supercharger network.

My First Experience

I took my children to the local science museum in honor of them being out-of-school on Juneteenth. The Science Center offers four free EV charging parking spaces split evenly between NACS and CCS (technically J1772 - this is important later) chargers. Both CCS spaces were occupied, but the NACS spaces were open, so I was excited to try out the new adapter.

I backed into the parking space, attached the adapter to the charging cable first (per the instructions), and then attached it to the car. A short delay and then I heard the various "clunks" as relays closed and the car and charger started negotiating with each other. But then...no charge! I tried a few times (including trying the NACS cable from the other parking space) and kept having the two systems refuse to talk to each other.

As I was deciding to move the car to a different parking space (where I wouldn't be blocking a charging space I couldn't use), the car next to me pulled out and freed up a CCS spot. I grabbed the cable, dragged it over to my parking spot, and plugged in. Success! I wondered what the issue was, but it was time to take the kids into the museum.

What Happened?

I did some further research and finally figured it out. The NACS standard uses the same pins on the plug for different purposes depending on whether the car is plugged into a level 3 charger or a "slow" charger. By contrast, CCS is adapted from the J1772 (compatible with levels 1 and 2) standard and then adds two pins for DC level 3 fast-charging; on CCS the car doesn't have to "know" what kind of charger it's connected to, the pins are always single-purpose.

The new Hyundai chargers are designed to connect to level 3 Superchargers, so the NACS adapter is configured for those chargers only. Because I was connected to a level 2 NACS charger, the pins were not configured to deliver power the way that the adapter or car expected. This caused the car to refuse the connection and not charge from the NACS adapter.

I was disappointed to learn this, becuase it means that if I want to connect to another level 2 NACS charger, I'll need to buy another adapter for NACS levels 1/2. We'd been getting by fine without an adapter and we will continue to do so, but my hopes were high that the adapter would solve all compatibility questions.

The Way Forward

Having the new adapter adds options to charge on the go for our EV. We still have a gas/electric hybrid that we've been using for road trips, but maybe we'll take Alanis (Isn't it IONIQ?) on future journeys.

Do you have any stories about charging an EV? Any recommendations on a level 2 NACS charger? Let me know at blog@saprobst.com or in the comments!