AC-to-DC conversion is happening constantly in all cars. The alternator generates three-phase alternating current, which batteries cannot store. An internal diode bridge rectifies this power into direct current to charge the battery and run the car's electronics.
For electric vehicles, this conversion is key for charging. When plugged into a home outlet, the onboard charger converts household AC power into high-voltage DC. This DC voltage is then stored in the lithium-ion battery pack.
If the rectifier diodes fail, AC voltage leaks into the car's wiring. This creates electrical noise, causing static in the radio and flickering dash displays. It will also prevent the battery from charging, leaving you stranded.