Some drivers struggle to use new liquid-cooled charging cables

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Electric vehicle drivers are just now beginning to use a new generation of ultra-fast DC charging equipment in Europe and the US that features liquid-cooled cabling and some are having trouble.

While many drivers are charging on this new equipment without a problem some complaints can be seen on PlugShare, the popular charging locator app and website. Often it’s hard to be sure exactly what went wrong based on the description.

Some failures to charge seem to be due to software glitches in new equipment. In other cases it might be due to poorly explained payment processing errors due to use of unsupported credit cards. For example, the payment readers on some Electrify America chargers have animated screens that imply support for Apple Pay but it isn’t actually supported yet.

Sometimes there can be a failure to charge due to physical connection problems even when the cable seems to be fully plugged into the vehicle.

The liquid-cooled cables being used today are typically supplied by the company Huber and Suhner under the brand name RADOX HPC. Other suppliers of liquid-cooled high-power charging cables such as ITT Canon and Phoenix Contact have been announced but are not yet as commonly in use.

The RADOX cables are relatively thin and light but are somewhat more resistant to bending and twisting than conventional charger cables. This can make the new cables harder to bring into final alignment with the inlet on the vehicle. Conventional cables rated to carry 350A or more would be heavier and difficult to handle in other ways and the connector pins need liquid cooling at high amperage.

At many older 50 kW charger installations the cables tend to end up sloppily unspooled on the ground where they get dirty and might even be run over by cars parking in a charging space. The new high-power chargers are being designed with cables that connect higher up on the dispenser and have a shorter usable cable length. The shorter lengths and the bend and twist resistance of the cabling can make for a more frustrating user experience. As the cable is extended to its maximum reach, the connector on the end naturally ends up in a horizontal position rather than in the vertical position necessary for plugging into a vehicle inlet.

A recently opened Electrify America site in Livermore, California has been frustrating for some customers. The cables are about 10 feet long and steel poles (bollards) are located two feet in front of the charging dispensers to protect them from contact with parking cars. This isn’t a problem for a Hyundai Kona Electric which has a charge inlet on the front of the car but other cars have the inlet just ahead of the driver’s door on the side of the car.

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There is no problem reaching a Chevrolet Bolt EV when parked very close to the charging dispenser.

This can work okay for a Chevrolet Bolt EV, which has a short front end, when parked within several inches of the protective bollards. However, if you park a bit further away it can be a real physical challenge with both hands to simultaneously pull the cable straight to the car for maximum length while bending and twisting it near the connector in just the right way as to align and fit snuggly into the vehicle inlet.

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The cable was difficult to maneuver and plug in with the Bolt EV parked with its license plate just 12 inches from the bollards. Unplugging from the car was even more of a struggle due to the stress on the cable.

Other cars like the Jaguar I-PACE are apparently having a harder time using the cables at the Livermore location. One owner in a recent post on a Facebook I-PACE group reported having to park his car within 6 inches of the bollards to get the cable to reach. Another I-PACE owner said he ended up parking parallel across two charging spaces to make it easier for the cable to reach the car.

The Audi e-tron SUV coming out next year would likely face similar challenges. Audi is a subsidiary brand of VW Group which is also the owner of Electrify America.

In a recent interview, Electrify America Chief Operating Officer Brendan Jones acknowledged the company is still learning from the real-world experiences of users and has installed longer cables at some locations in response.

Even if the cable reaches and plugs into a car it may not actually work. In order for the plug and inlet to connect there has to be a certain amount of gap to allow for insertion and removal of the plug when it is not absolutely perfectly aligned with the inlet. If there is not enough gap then the plug will be very difficult to insert or remove. If there is too much gap the plug may not stay fully inserted. Once the plug has been connected it still has room to be pushed slightly from side to side or to sag down a bit due to cable weight or stress.

This reporter personally experienced a problem trying out Recargo’s new location in Prunedale, California. Several attempts to charge a 2017 Chevrolet Bolt EV failed on two different dispensers.

Eric Way, who hosts the YouTube channel “News Coulomb”, experienced the same problem with his Bolt EV on a different day at the same Prunedale location yet other Bolt EVs have charged there successfully without trouble. He also experienced the same problem at EVgo’s new 350 kW charger in Baker, California which uses the same cable and connector design as the Recargo location but on a different brand and model of charging equipment. He posted a video on YouTube about his experience and documented a workaround that allows for successful charging.

He says on the video that this could be an issue that is specific to Bolt EVs built during the early months of production in late 2016 or early 2017. However, according to a GM spokesperson, there hasn’t actually been any change to the Bolt’s charging inlet design since it began production in late 2016.

GM says it is investigating the issue. It’s not unusual for interoperability and compatibility problems to show up in new equipment even though manufacturers of standards-based products hold cooperative prototype testing events to try to find problems during development. It isn’t known if this connection issue is commonly occurring with other EV brands and models.

Fortunately, there is an easy workaround for the issue. As Eric Way demonstrates in the video, the issue can be avoided by supporting the cable weight during the first few seconds as the charger initiates communications with the car. Just before the charging begins, an actuator or motorized latch on the vehicle inlet pulls the plug snuggly into the inlet and holds it securely for the duration of the charge. Once the cable is latched it no longer needs to be supported by hand.

The original engineering reason for latching the plug into the car is to prevent someone from unplugging while high power is present on the pins during charging as this could cause dangerous electrical arcing. The latch releases its hold on the plug only after the charging session has ended.

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Categories: Charging

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