ISO 15118 – how a bus talks to a charger

ISO 15118 is an international standard that governs the way electric vehicles communicate with charging stations. It defines how devices should automatically recognize each other, exchange data, and manage the charging process—making it smooth, safe, and intelligent.

Importantly, ISO 15118 standardizes vehicle-to-charger communication using PLC (Power Line Communication) technology. Although commonly referred to as “a single connection,” DC charging actually involves two power conductors (+ and -) and three separate lines for communication: CP, PP, and PE. All of this is integrated into one cable set—no cards, logins, or extra steps required.

The vehicle can send a digital certificate to the station (known as Plug & Charge), and if verified, the charging session starts automatically. During the process, systems continue exchanging information: adjusting power, monitoring battery status, and reporting data to the operator. It’s worth noting that Plug & Charge is still a relatively new feature and not required for ISO 15118-compliant charging. Currently, it’s more commonly used in passenger vehicles.