have a small backup battery
As far as I understand, that 12V battery was that backup…
Nope it’s a separate battery used like in a normal car to power the low voltage stuff so you don’t have to use high grade power lines to run the windows and doors
During the pandemic my car sat in the garage until the battery died. After 7 hours of charging it, turned on the car and found the hybrid battery was almost full.
I get why the high and low voltage systems are separate, but damn that was one of those “Really!?” moments…
It’s much much much cheaper to use the same 12V systems that other cars use.
Kia/hyundai solved this by having a disconnect on their (li-ion) 12V battery. When the voltage gets low it completely isolates the battery. There is a button inside the car that reconnects it right before starting the car.
Not anymore, they’ve updated the platform to be 48v (which they shared the docs with the rest of the industry) and are using lithium batteries in both systems instead of lead acid. They’re supposedly supposed to last the lifetime of the vehicle instead of having to be replaced every 4-5 years.
https://insideevs.com/news/656775/tesla-switch-48v-voltage-system/
Only the cyber truck. Model S and 3 refreshes are still on the legacy platform, with a lithium ion 12V.
I should have said a small battery backup done properly knowing full well the abysmal QA of that company.