A disturbing number of Chevy Bolts have caught fire due to battery cell malfunctions. GM issued two recall-level software updates, but neither solved the problem. Recently, GM recalled every Chevy Bolt for battery fires. These dramatic events have implications far beyond the Chevy Bolt, affecting all Ultium Platform electric vehicles, including the GMC Hummer EV and the Cadillac LYRIQ. The Chevy Bolt recall may even impact the future of EV battery cell manufacturing.

Chevy Bolt’s Ultium Battery Cell Is At The Heart of All GM EVs

General Motors is pioneering electric vehicles and new ways to manufacture them. According to GM, a standard power module made of long pouch battery cells is at the heart of all its planned EVs. The manufacturer intends to arrange these modules, in different numbers and configurations, to build the battery packs for EVs ranging from Chevy Bolts to GMC Hummer EVs. GM has branded this flexible technology the Ultium Platform.

After GM pledged to go all-electric by 2035, the company began looking for a battery manufacturing partner. GM finally announced a partnership with LG’s Energy Solutions division. As South Korea’s leading battery manufacturer, LG was an obvious choice to build GM’s Ultium Platform battery cells.

GM To Spend $1 billion To Expand The Recall of Chevy Bolt EV Due to Safety

The Chevy Bolt launched in May of 2017. Since then, these new EVs have begun to catch fire with alarming frequency. Eletrek.co maintains a list of known Bolt fires, all of which are believed to be battery-related. At least twelve Chevy Bolts caught fire in one year. GM then recalled certain Chevy Bolts two separate times, each time installing a software patch to reduce the battery’s capacity to about 60%. Newly manufactured Bolts came from the factory with the same software patch. Four recent fires affected post-software-patch models (several 2019s and one 2020). After these recent fires, GM announced a recall on every Chevy Bolt ever made. GM clarified that it would not be doing another software patch but replacing every Bolt’s battery instead. 

‘A Perfect Storm’ of Ultium Battery Cell Defects

After GM announced the historic recall, Arts Technica interviewed the technical director of The University of Michigan’s Battery Lab, Greg Less. Less explained that two simultaneous defects would need to occur for a brand new battery module to catch fire. First, LG must have assembled one of the long pouch battery cells with the anode and cathode too close to one another (likely because of a torn anode tab). But every cell features a separator designed to keep the anode and cathode from touching. So the tech-giant must have also accidentally folded the separator during assembly. Less concluded, ““What we’re looking at is a perfect storm.”

Less speculated that a single “miscalibrated” robot on the assembly line could be both tearing anod tabs and folding separators. He specified that not every cell manufactured is compromised: LG and GE’s quality control would have flagged the issue if that were the case. But enough cells suffer the two simultaneous defects that multiple vehicles have caught on fire.

The Future of GM’s EVs: Hummer and Cadillac LYRIQ

GM’s Chevy Bolt recall will be a billion-dollar setback. But the Detroit giant’s woes do not end there. 

The compromised LG long pouch battery cells are at the heart of every upcoming Ultium Platform EV. This includes every Hummer EV and Cadillac LYRIQ that GM has already assembled. Unfortunately, GM will have to replace the battery modules in these vehicles, which will likely delay their release.

The harmful publicity is piling up for GM’s EV ventures: The GM-sponsored Lordstown Endurance prototype also went up in flame because of a battery issue (that was not even an Ultium Platform battery). Perhaps, under mounting pressure, GM will find a new battery assembly partner. Or perhaps GM and LG will reexamine and update their joint venture factories. Only time will tell how GM will address Ultium Platform concerns.