On-Board Charger Unit (OBC Unit)

https://www.empevmobility.com/products/on-board-charger-unit-obc-unit/

On Board Charger Definition
An on-board charger unit (OBC) is a device used in electric vehicles (EVs) to convert alternating current (AC) power from the electrical grid into direct current (DC) power to recharge the vehicle's battery pack. The EV OBC is typically located within the vehicle and is integrated into the charging system. It is responsible for managing the charging process, including monitoring the battery state, regulating the charging voltage and current, and ensuring the safety and efficiency of the charging process.