"EV batteries are defying expectations" — the good-news stat quietly compares new cars to old ones
The number looks like a triumph: 1-in-12 early EVs needed a new battery, versus 0.3% of cars built since 2022. Then a commenter points out you're comparing barely-driven new cars to a decade-old fleet — and that calendar aging never gets mentioned.
The WSJ piece argues high-mileage EV batteries are outlasting fears, citing a 2025 Recurrent study (1-in-12 for 2011–2016 cars vs 0.3% for 2022-on) and Geotab data that heavy fast-charging loses range twice as fast.
The thread's survivorship-bias catch is clean: of course a three-year-old car hasn't needed a replacement yet — and every article like this skips the calendar-age degradation that kills batteries regardless of miles.
The headline number, and the comparison inside it
The Wall Street Journal piece argues EV batteries are aging far better than early buyers feared. The load-bearing contrast, quoted in the thread: roughly 1 in 12 EVs built 2011–2016 needed a battery replacement, versus only 0.3% of EVs built from 2022 on, per a 2025 Recurrent study. It also notes that batteries frequently fast-charged at high power lose range about twice as fast as those charged gently, per telematics firm Geotab. Overall framing: high-mileage EVs are holding up, so relax.
The thread didn't dispute that batteries improved. It disputed that the flagship number proves it.
The confound the stat is built on
"This is kind of a dumb comparison. It would be more useful to know how many vehicles had to have replacements within X years of being put in service. Obviously newer vehicles are much less likely to have needed a replacement at this point in time." — a commenter naming the age/survivorship confound
Then the failure mode these stories tend to omit entirely:
"They still die by calendar age based degradation. High miles low years isn't interesting. We know that works well… They don't like talking about the calendar age degradation. Every article like this leaves that part out." — a commenter on the omitted calendar-age failure mode
And a useful bit of how the industry even knows lifespan without waiting a decade:
"No manufacturer is testing the batteries life by just charging and discharging them daily for a decade… they are using artificial acceleration techniques like getting the battery hot… heat is the big enemy for li-ion batteries" — a commenter explaining accelerated battery-life testing
The good news, minus the spin
Batteries really did get better — chemistry, thermal management and packs all improved between 2015 and 2022. But "0.3% vs 1-in-12" isn't the proof; it's mostly the fact that 2022 cars are three years old and 2015 cars are ten. The honest version keeps the optimism and drops the trick: measure replacements at the same age, and say out loud that calendar time, not just odometer miles, is what quietly eats range.
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Europe's heat charts hide a paradox: cleaning up our air is part of why it's warming faster
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