3 ms·
At least on AC Level 1/2 charging (using just a J1772 port) the signalling is pretty rudimentary if I remember correctly. Something along the lines of the car p
by i-am-gizm0 3y ago
At least on AC Level 1/2 charging (using just a J1772 port) the signalling is pretty rudimentary if I remember correctly. Something along the lines of the car puts out a square wave on one of the signalling pins and based on the resistance it sees it knows whether it's plugged in and how much power it can charge, so there isn't much room (dare I say any) way to interact much with the car through that port. I don't know how DC charging works but I assume there's a little bit more smarts to it. Tesla on the other hand is a completely different story.
- rtkwe 3y agoThe really high voltage fast chargers as far as I understand them connect directly to the battery bypassing the cars battery charger to directly charge the battery not sure how much communication there is on those channels though.
- vegardx 3y agoYou're probably thinking about the on-board inverter, it's often referred to as a battery charger. The battery management system is entirely within the car, and the car will tell what voltage and amperage to deliver to it. The design of CCS2 is actually quite nice. There are pins for singalling that, if broken, will immediately shut down power delivery. This means that you can just pull the cable out safely, without risking arcing or electrocuting yourself.
- rtkwe 3y agoMy understanding was it also bypassed the BMS but I may have confused what they were saying it's been a minute.
- rlpb 3y agoWhen I've done DC rapid charging on my Leaf, I noticed that the charger knew the battery percentage reported by the car. That seems likely to be digital signalling to me, so suddenly there's the risk of buffer overflows and suchlike. I've not seen this on AC, but when I looked into this previously I got the impression that there exists a digital signalling protocol established by modulating something ignored by older cars and chargers that can be optionally supported. If that's the case then there's potentially attack surface there, too.
- fnordpiglet 3y agoThat’s why I only buy cars written in rust.