Newswise — The process of accessing a charging app, swiping a card through a reader, plugging the charging cord into the outlet and waiting for the battery to charge should be a seamless experience for users. Every step depends on interoperability.

A task force at the U.S. Department of Energy’s (DOE) Argonne National Laboratory has brought together scientists, software developers, vehicle manufacturers, other national labs and industry partners to address a priority for electric vehicle (EV) drivers: making sure the charging technology works.

Argonne is leading a task force tapped by the Joint Office of Energy and Transportation (Joint Office), which funds the National Charging Experience (ChargeX) Consortium.

“We work on a concept called vehicle grid integration, making sure that the transportation system — which hopefully in the future will be majority electrified — is integrated properly with the grid operators and the utility systems,” said Daniel Dobrzynski, group manager for grid integration technology at Argonne who oversees the ChargeX Testing Task Force.

“For example, what if the credit card reader didn’t work, and they had to try a few different credit cards — or they had to access another function on their phone — and by that time, the system timed out or the vehicle fell asleep?” — Daniel Dobrzynski, group manager for grid integration technology at Argonne

The process of accessing a charging app, swiping a card through a reader, plugging the charging cord into the outlet and waiting for the batteries" href="http://www.anl.gov/science-101/batteries" target="_blank">battery to charge should be a seamless experience for users. Every step depends on interoperability — the interaction between electric vehicle chargers and vehicles.

ChargeX has three working groups that focus on defining the charging experience, testing its reliability and usability, and developing solutions to help improve that experience on a large scale. These working groups have already released helpful publications on error codes and payment recommendations to help streamline the charging experience for drivers. Now, the testing methodology task force within the scaling reliability working group is creating frameworks for testing interoperability.

“Some of that work has to do with management controls and communications among the driver, the vehicle, and the back end or utility systems,” Dobrzynski said. ​“We also assess charging technologies, characterizing how their communications work and what the capabilities and latencies are, whether you’re charging at home or at public or semi-public places like airport parking lots.”

When an electric vehicle driver plugs in, all the technologies involved — the app, the charging station, the payment system server and the vehicle itself — should all communicate reliably with one another, regardless of what company manufactured them. Recently, the Task Force assembled thirty attendees, representing vehicle manufacturers, technology developers, government entities and public interest groups, to come to a consensus about what ​“interoperability” should mean and how technologies should be tested to meet the standards.

“We want to keep industry heavily involved, seeing as they are the ones building the technology,” said Task Force lead Sam Thurston, an electrical engineer with Argonne’s Transportation and Power Systems division. ​“During our meeting, we listened closely to their feedback to gather the most realistic criteria for a variety of possible scenarios.”

Currently there isn’t a comprehensive set of tests for ​“use cases” that a driver might encounter, Dobrzynski says. ​“For example, what if the credit card reader didn’t work, and they had to try a few different credit cards — or they had to access another function on their phone — and by that time, the system timed out or the vehicle fell asleep?”

The Task Force has currently outlined 16 distinct testing categories, each with its own subset of detailed test scenarios. These scenarios consider what a user might experience in the real world, including a wide variety of both ​“happy-path” and ​“edge-case” testing. ​“For example, whether you pay first or plug first, or use smart charging features. We are looking to capture as many of these unique scenarios as possible,” Thurston explained.

The Task Force included test cases surrounding equipment issues, such as faulty cables, loss of internet signal or loss of power. They also explored charge discovery cases — such as what happens if a user starts with a partially inserted connector or a broken latch — and power transfer issues that might arise from conditions like temperature changes.

“We worked through all 16 test categories in depth, and the engagement was excellent from everyone present for the meeting,” Thurston said. ​“We now know what needs to be done to fully complete this document.”

“There was major interest from those participating in bringing this document to their technical groups for future collaboration, which was very exciting,” he added.

“Reliability is the foundation of a positive EV charging experience, and consistent testing is key to ensuring reliability,” said Sarah Hipel, program lead for standards and reliability at the Joint Office. ​“The work of the ChargeX testing task force to identify and specify key testing scenarios will help improve the EV charging experience for drivers today and in the future.”

ChargeX’s testing parameters will help set the standard at interoperability testing events, such as those hosted by CharIN, a global association dedicated to promoting standards in the field of charging systems. CharIN’s North American ​“Testival” and Conference will take place in June in Cleveland, Ohio. ChargeX representatives from Argonne, DOE’s Idaho National Laboratory and DOE’s National Renewable Energy Laboratory will attend to help coordinate, moderate and gather results from prescribed testing portions of the Testival.

“We are bridging the gap between industry members and event hosts in the spaces where they gather,” Thurston said. ​“That’s where ChargeX is really excelling.”

Argonne National Laboratory seeks solutions to pressing national problems in science and technology by conducting leading-edge basic and applied research in virtually every scientific discipline. Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.

The U.S. Department of Energy’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://​ener​gy​.gov/​s​c​ience.