CHAdeMO

CHAdeMO is a DC fast-charging connector and protocol standard developed by a consortium led by Nissan, Mitsubishi, and Toyota in the mid-2000s. The name is a Japanese pun meaning roughly "tea time," reflecting the goal of charging a vehicle in the time it takes to drink tea, typically 20 to 30 minutes. Unlike AC charging via a vehicle's onboard charger, CHAdeMO supplies direct current at high voltage directly to the battery pack, bypassing the vehicle's power electronics and enabling much faster energy transfer. The connector itself is roughly the size of a large power plug, with a distinctive trapezoidal shape, carrying up to 62.5 kW (later extended to 100 kW in version 2.0), and requires a dedicated charging station.

The standard emerged as Japan's answer to EV infrastructure, first deployed on the Nissan Leaf in 2009. It gained traction across Asian markets and found adoption by some European and American models, though it never achieved global dominance. The connector uses a handshake protocol over a CAN bus to negotiate power delivery, request authentication, and manage thermal limits. Typical charging curves taper significantly once the battery reaches 80 percent state of charge, meaning real-world charging times extend well beyond the initial fast-charge phase.

Competing and Superseding Standards

CHAdeMO competed directly with the Combined Charging System (CCS) standard, which combined AC and DC charging in a single port, and Tesla's Supercharger network using a proprietary connector. By the early 2020s, the automotive industry shifted away from CHAdeMO. In 2023, the CHAdeMO Association announced that new vehicles would no longer use the standard, and major Japanese manufacturers began adopting CCS. Thousands of CHAdeMO stations remain operational worldwide, primarily in Japan, Europe, and limited U.S. locations, serving older Nissan Leafs, Mitsubishi i-MiEVs, and other legacy EVs.

Charging speeds and cable management differ significantly from AC Level 2 charging. Most public CHAdeMO stations supply 50 kW or less; 100 kW stations are rare. The connector uses water cooling in cables to manage resistive heating at high current. Connector degradation and session interruptions are known failure modes, particularly where infrastructure maintenance has been poor. Cold weather reduces charging rates substantially, a significant practical issue in northern climates.

For technicians and fleet operators, CHAdeMO remains relevant only for maintaining existing EV fleets. New procurement decisions, charging infrastructure investment, and vehicle sourcing now center on CCS or emerging alternatives like NACS (Tesla standard adopted by other manufacturers). Understanding CHAdeMO is historical competency in EV maintenance but no longer guides capital investment in charging networks.