Maintaining EV Chargers Yet Another Challenge

The lack of charging infrastructure is a major impediment to EV growth, but maintaining chargers once established also is key to successful operations.

Best practices should include integrating chargers within the fleet’s enterprise system for monitoring, preventive maintenance scheduling and cost tracking. (SAE/Ryan Gehm)

Industry experts have trumpeted ad nauseam the need to expand electric vehicle (EV) charging infrastructure for the past half-decade or more. Those calls continued at the recent Green Truck Summit in Indianapolis, Indiana. “The biggest obstacle at the moment is the charging infrastructure,” Ray Eyles, chief program engineer for Ford Transit Vans, said during an EV Upfitting session at the event. “We know that charging is going to be one of the major impediments to commercial customer uptake.”

Public charging infrastructure specific to electric commercial vehicles, such as the Freightliner eM2 box truck, does not exist, said Alexander Voets of Daimler Trucks North America. (Freightliner)

Two options face fleets: install expensive proprietary infrastructure or rely on public infrastructure. The latter is still problematic. “Currently, there is no public charging infrastructure for commercial vehicles specifically,” said Alexander Voets, eMobility product and sales strategy manager at Daimler Trucks North America. He noted that while the plugs at passenger-vehicle charging facilities will indeed work for battery-electric trucks, the physical size of the parking spots is not so accommodating. “I charged there before with a 26-foot box truck – I certainly got some raised eyebrows,” he said to audience laughter.

Vertically integrated companies that provide their own hardware and software can help alleviate the number-one EV charger issue: software integration. Hino Trucks featured this ChargePoint fast-charger in its booth at the NTEA Work Truck Show. (SAE/Ryan Gehm)

Certainly, the dearth of current EV charging infrastructure is no laughing matter, and the challenges don’t stop once a charging setup is even established. Properly maintaining chargers poses additional challenges for which fleets must prepare. During a breakout session at the Green Truck Summit, Mike Terreri, EV and charging product manager for AssetWorks, discussed maintenance concerns and recommended best practices.

“Range anxiety has been replaced by charger anxiety,” Terreri asserted. “Drivers are learning to care less about how many chargers are installed at their destinations, and more about whether those chargers are in service. This is true for both consumers and fleets.”

Terreri cited data collected by a U.S. Pacific Northwest utility a few years back showing charger uptime of about 95%. Networked commercial EVSE (supply equipment) didn’t fare as well, with an average uptime of 86-93%. (Non-networked EVSE performed better at 98%.) “We don’t really have statistically significant data [to know] what the industry averages are, but we know that this is an issue, at least anecdotally,” he said, noting that today’s new networked chargers likely will achieve 95% uptime. “As the technology matures, charger uptime is improving, but progress still needs to be made.”

Depending on the type of infrastructure, the preventive maintenance schedule will differ. For example, DC fast chargers are unique from Level 2 AC chargers in that they will require inspection of air filters and cooling. Ford Pro revealed its full lineup of fleet-focused charging stations at the NTEA Work Truck Show. (SAE/Ryan Gehm)

A consistent pattern has emerged, however, for the time it takes to repair chargers. “When chargers do go out of service, no matter how often, it can take an average of about two to three weeks to resolve,” he said, noting that parts replacement and technician availability can influence that timeframe.

The number-one EV charger issue, Terreri said, is software integration. “Companies that are vertically integrated produce their own hardware and software, but that’s not always the case,” he said. Often, charger, network and vehicle software are from different entities, which can lead to compatibility issues. And not all network providers perform full validation testing prior to deployment, which also can pose problems. Or, after some time, hardware over-the-air and network updates can create issues even after successful commissioning.

Component failure – “a symptom of a nascent industry,” Terreri said – is the second-most common issue with EV chargers. Root cause analysis requires technical expertise and communication with the service provider and OEM. The third main issue is manufacturing and design errors, such as improper seating of electronics connectors or insecure compression-sleeve fittings for charging cables.

Small problems can cascade, he said. For instance, if the plate-to-latch distance is out of tolerance, users could damage the SAE J1772 connector or other parts by forcing it onto the vehicle or holster. Vandalism – e.g., copper thieves – and accidental vehicle/plow collisions also can impact (pardon the pun) charger performance.

Best practices suggested by Terreri include integrating the chargers within the fleet’s enterprise system for monitoring, preventive maintenance (PM) scheduling and cost tracking. Redundancy is another must, so that when chargers go out of service, fleets still have the charging capacity to maintain operations. "Part of that maintenance plan should include maintenance schedules. In the same way that organizations have rigorous PM regimes for vehicles, the same should be true for infrastructure,” Terreri said. “Infrastructure can be as costly of an asset or investment as the vehicle.”

Depending on the type of infrastructure, the PM will differ. For example, “DC fast chargers are unique from Level 2 AC chargers in that they will require inspection of air filters and cooling,” Terreri said. Air inlet filters might need replaced annually, while air outlet filters likely can last two years. Coolant should be checked and flushed every year. Bottom line: As the industry continues to scale up EV operations, resolving charger maintenance issues quicker – or preventing them from occurring in the first place – will be key to reliably keeping EVs up and running.