Why Is My Electric Vehicle Dead? Check the 12-Volt Battery - WSJ [View all]
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Turns out, the problem wasnt with the main battery, but the smaller, low-voltage onethe kind that has been found under the hood for decades. In some new electric-car models, these 12-volt batteries are dying repeatedly and unexpectedly, leaving drivers stranded and needing a jump to get going again.
It isnt clear how widespread the issue is. But it has taken many owners by surprise, led to numerous complaints online and affected some high-profile EV launches in recent years from major car brands, such as Hyundai, Rivian and Cadillac. It also has prompted at least two regulatory probes.
While these batteries dont move the vehicles themselves, they do provide juice to the interior lights and electronics, which in EVs tend to be far more sophisticated and power-hungry.
As a result, the 12-volt batteries are almost always on and deplete faster than those in gas-powered vehicles, said Amod Kumar, an industry analyst at research firm S&P Global Mobility.
Some car companies have also struggled with software glitches and other hardware problems that have accelerated the drain on the battery, even when the car is in park.
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https://www.wsj.com/business/autos/why-is-my-electric-vehicle-dead-check-the-12-volt-battery-67d432dd?st=o1hi9tcgve5sfbn&reflink=desktopwebshare_permalink
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