Lets say you're sending me emails if your current EV charger wants to work with the Bolt / Leaf / Tesla / Taycan that you're buying next. First, it shows that the EV dealers obfuscate charge compatibility (something I've learned myself in researching this topic), and second, it shows that the EV market has matured to the point that it has a number of sequential buyers, just like the traditional car market.
First, that thing on your garage wall or sticking up in a parking lot that you call a charger is probably not a charger. It's an Electric Vehicle Service Equipment, or EVSE, device. Basically, a smart outlet. The charger itself is in your car, carefully designed and mated to the specific battery it uses.
The first task your car's built-in charger tackles is taking is the in-progress of the battery. This is similar to what your phone's charger does with it.
AC or DC, there are three levels of EV charge:
This is basically 120V AC house current, capable of up to two kilowatts of power. It's a survival charge, good enough to get to a level 2 charger. If you need a full charge from Level 1, book a room. It will take 24 hours or more for most EVs.
This is a charge from a 240V AC source, capable of delivering 90 kilowatts of power. This level of charge is what carmakers are talking about when they can fully charge overnight, typically within six to eight hours.
This one is a little messy. It can refer to a 480V AC connection, continuing the pattern of doubling voltage in each successive charge level, but in the US, Level 3 usually means a DC power source. It's very powerful and requires no messy, inefficient conversion from AC. Tesla Superchargers are the best known example of Level 3, putting out 120 kilowatts of direct current. Porsche has said they will be up the Level 3 ante with 350 kilowatts of Level 3 charge locations and Tesla has in 2019. The key to these and other forms of Level 3 DC charging is a charge measured in minutes, not hours.
Now, to connect to any level of charge source in the US, you'll need one of the four major charge connectors.
Clumsily named after a Society of Automotive Engineers specification number, J1772 is the most common charge connector in the US and can either transfer Level 1 or Level 2 power levels.
It has three large pins that correspond to AC line, neutral and ground, just like yours at home, and two smaller pins for data communications between the car and EVSE.
Add a couple of DC to the bottom of a J1772 and get a CCS or Combined Charging System connector.
It's sort of an ungainly thing with those grafted-on DC charge pins, but it's good enough for Porsche which.
This connector probably would J1772 in the Leaf, Still the best selling EV of all time.
CHAdeMO is a DC fast-charge connector only, with two big pins carrying DC current and two quad-pin data terminals for analog and digital communication. The Tokyo Electric Power Company explained CHAdeMO's cryptic name as "a pun for 'O cha demo ikaga desuka' in Japanese, meaning 'Let's have a while while charging.' Http://www.cnet.com/" I kid you not.
Then there's Tesla
Tesla has the most elegant charge connector of all. It's proprietary, of course, packing in pins for Level 1, Level 2 and Level 3 DC charging along with data communication, all in a slim, elegant handle.
You do not find Tesla's connector at any non-Tesla charge location, but they do provide the J1772 connector pins into a Tesla connector.
Tesla Model 3 : If you go to a non-Tesla Level 3 charge location, the third party EV charge companies tell me there's a further twist on charging to a blocked data handshake. Tesla Supercharger If you want to do a major charge on your model 3 in minutes, not hours.