Home Cars News A real-world test of BYD's Megawatt Flash Charge pushed battery temps to 169.6°F. Digital Trends A real-world test of BYD’s Megwatt Flash Charge technology showed the battery hitting 169.6°F during a charging session. That’s hot enough to roast a turkey , and well above China’s recommended safety ceiling of 149°F for lithium iron phosphate battery cells. The test, conducted by an automotive blogger who livestreamed the session (via ChinaEVHome ), has raised concerns about whether the heat generated by ultra-fast charging degrades long-term battery health. Why the heat matters Under normal driving and charging conditions, EV battery cells typically operate between 68°F and 86°F, with most vehicles flagging overheating warnings above 140°F. Temperatures in the range recorded during the test put stress on the Solid Electrolyte Interphase (SEI) layer, a protective barrier that keeps the electrolyte separated from the anode while still allowing lithium ions to flow.…