GM is working to ensure that its new Hummer EV avoids battery defects

A 2019 Chevrolet Bolt EV caught fire in a home in Cherokee County, Georgia on September 13, 2021, according to the local fire department.

Cherokee County Fire Department

DETROIT – As General Motors struggles to repair defects that caused fires in at least 13 Chevrolet Bolt EVs, the automaker is working aggressively to ensure that the same problem does not seep into the next generation of Ultium batteries and its long-awaited relaunch of an all-electric version of Lobster this fall.

The new power system is crucial for the car manufacturer’s future as it is aimed at offering exclusive electric vehicles by 2035. The batteries and the company’s entire Ultium system – platforms, engines and other components – are expected to support every electric car for GM for the foreseeable future.

Problems with Bolt – the company’s flagship mainstream EV – have prompted the carmaker to recall all electric cars since production began in 2016. Fixing the vehicles, including completely replacing some batteries, is expected to cost $ 1.8 billion.

That cost – an average of about $ 13,000 per vehicle – highlights a gamble for carmakers who plan to use standard platforms or battery cells to power huge amounts of vehicles. If there is a problem, it will be expensive.

This is one of the reasons why officials throughout GM have worked aggressively “around the clock” to fix the problems and secure future electric vehicles such as the GMC Hummer EV and Cadillac Lyriq – two of the first GM models to use their Ultium batteries – do so. do not have the same problem. They also work with wireless technology that allows GM to detect potential defects earlier.

“There’s a commitment across the company to not only address the problem with the LG cells and Bolt but also ensure that all future products are set for success,” Mike Harpster, chief engineer for electrification propulsion for GM, told CNBC during a deep dive. in the carmaker’s upcoming Lyriq. “It does not create the fault or defect, but there is also how the package and the vehicle react to it. And on both these fronts we move very aggressively.”

The car manufacturer’s efforts extend beyond its own organization. GM’s CFO Paul Jacobson recently said that GM engineers are working with LG Chem, which manufactures the batteries, to “clean up the manufacturing process” and implement some “GM quality measures” at LG’s factories.

On Monday, GM announced corrections to the manufacturing process for the battery cells as well as updated monitoring software for the vehicles. Both are expected to be used for future vehicles, Tim Grewe, head of GM’s electrification strategy, told reporters on Monday.

GM is seeking compensation from LG, which manufactured the defective parts at factories in South Korea and Michigan.

New battery systems

The increased quality efforts come when GM builds a US-based battery cell plant through a joint venture in Ohio with LG Chem called Ultium Cells. It is the first of several battery factories expected from GM in the coming years.

While the Ultium batteries include new chemistry and production processes compared to LG’s production and cells, GM is taking lessons from the current production process, including safeguards and monitoring, for the new factories.

“There are improvements in the process that were learned from the current process,” says Harpster, who was chief engineer for Bolt EV’s propulsion system. “It’s not just at the cellular level, it’s at the modular level, the packing level. Everything we’ve done before, we’ve done with a partner, LG. All these lessons go in here to drive it to the next level.”

Grewe told CNBC earlier this month that the new production “is no more vulnerable” than anything the company does today.

“Any pollution anywhere can cause problems,” he said. “If you look at the battery facilities we have today, there are all kinds of controls that are looking for it.”

GM CEO Mary Barra said last month that the new plants will “apply all of General Motor’s quality processes to the manufacturing process”, signaling that the company expects better quality controls in place at the new facilities.

“We work every day to make sure that what we do is validated and tested. When we find a problem like this, and this again, happens to be two rare manufacturing problems in the same cell, we will deal with it,” he said. she on August 4 during an interview on CNBC’s “Squawk Box”.

Barra emphasized that Ultium is a completely new battery system, but manufacturing batteries will always be more volatile than assembling a traditional vehicle. The batteries can not only be emptied and refilled later as car manufacturers can do with petrol.

“Manufacturing processes will really need to be tightened up,” Guidehouse Insights chief analyst Sam Abuelsamid told CNBC earlier. “It’s part of dealing with how batteries behave. They do not like heat, and they do not like contamination. They are very sensitive.”

Vermont State Police released this photo of the 2019 Chevrolet Bolt EV that caught fire on July 1, 2021 in the driveway of State Representative Timothy Briglin, a Democrat.

Vermont State Police

Wireless monitoring system

The “rare manufacturing defects” in Bolt EVs are a broken anode tab and a weight separator that when present in the same battery cell increases the risk of fire, according to GM.

While GM continues to ensure that cell manufacturing is addressed, it may be able to identify such problems in the past with Ultium-powered vehicles.

Specifically, the new battery cells will be able to communicate wirelessly, giving GM additional data 24/7 to evaluate any issues. Bolt EVs, by comparison, can not make major updates to their software remotely, and only communicate when the vehicle is running or charging, according to officials.

General Motors unveiled its all-new modular platform and battery system, Ultium, on March 4, 2020 at its Tech Center campus in Warren, Michigan.

Photo by Steve Fecht for General Motors

“Everything can be updated instantly,” Grewe said. He added that the wireless system would probably have helped the company determine that a problem was present “a little faster.”

What the wireless system could do faster is to reset the batteries for the batteries remotely to reduce the risk of fires, he said. Currently, Bolt EV owners have to do it themselves or take it to a dealer to reset the software.

The wireless battery monitoring system, which will be standard on all Ultium vehicles, can also refocus the network of modules and sensors as needed, helping to protect the health of the battery during the life of the vehicle.


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