Certificate for charging station

Good morning,
I have a charging station and with some vehicles it doesn't work because I haven't the certificates to start a TLS communication required by the vehicle.
The charging station shall send a list of V2G Root Certificates to the vehicle before the charging process can start.
My question is: Can I use Let's Encrypt certificates for this purpose?

Thank you!

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Hi @str, and welcome to the LE community forum :slight_smile:

It is a very interesting question.
Unfortunately, I'm unable to find much information that specifically covers the TLS specs required for that connection.

ISO 15118-20 only covers the communication between the vehicle and charging station - it doesn't cover the cert used.

So, if you have a copy of a public cert currently being used in that system, we may be better able to compare it with an LE DV cert.
That said, do you have a method to install an LE cert (or any third party) into that system?
If so, please post any instructions on that here; It may better explain the requirements for such.

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It does sound cool! I think this is not domain validated though so there's no prospect of using Let's Encrypt (maybe ACME would be possible).

This sounds like Hubject? GitHub - hubject/openPlugnCharge

A few other charging manufacturers (like Tritium) have suggested using vehicle certificates to authenticate cars for charging sessions but it's usually accompanied with PR spin that makes it sounds like they invented certificates. I'm not sure if the EV industry actually standardized on anything for this.

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Can you define how the V2G root list is defined? If so then you can run likely your own Certificate Authority and upload your own root for the cars to download (I assume it's less about them trusting you and more about you trusting them?). Looking more at the hubject stuff it's fairly complex (many parties involved requiring many trust agreements) and would require a subject matter expert to implement for real.

This is of course completely off topic for Let's Encrypt but it's the type of stuff I'm interested in :slight_smile: I develop and host the tools/database/API for https://openchargemap.org (as a volunteer).

I'd guess that if you own the charging stations it's probably easiest to add them to a larger established network as part of a roaming agreement, and bill via the larger organisation.

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