Prime 2023 12V battery integrity on EV

I suspect it is the same for pretty much every EV / hybrid out there - they do not have alternator, they use traction battery to charge 12V battery.

 

On the Prius, the ICE does not charge the 12-V battery, as there is no alternator. The 12-V battery is charged by the high-voltage battery. Note that the car needs to be in the READY mode for the 12-V battery to be charged.

Likewise, the 12-V battery does not start the ICE, as there is no starter.

 

Plug ins, and some hybrids, use a DC to DC converter to step the high voltage coming out of the traction battery down to 12 volts power all the those accessories in the car. This will also charge the starter battery. Of course, the car needs to be in Ready mode or fully on for the traction battery to supply energy to the converter. So an EV chargers up the starter battery while it is driven, just like an ICE car.

The PP will also charge the 12 volt battery while the car is actively charging. Not sure if it is at just a maintenance rate or while increase its state of charge though.

 

They still haven't gotten rid of the 12v battery? What a PITA! On my Gen3 it was a small battery in the trunk. It lasted 8 years and was old $40 to replace. In my Gen4 it is a $200 battery under the hood that lasted just 4 years. Where is the 12v battery in the Gen5 and how expensive is it to replace?

 

It's back in the hatch (right corner near the door). I don't know the replacement cost

 

where did you get a battery for $40.? i paid $200, in 2018, and most here have paid similar

 

Yep. I think I paid around $175-$185 in late 2021. Or maybe I'm misremembering and it was over $200(I was in a hurry at the time). It's currently $239 MSRP at Toyota dealerships for a gen3.

Doing a quick search, I'm seeing a low of around $240 for a few brands of battery and almost $300 for an Optima.

 

There is a vast number of reliable, well tested parts that use 12 volts. Did you really want to pay for "hybrid" bulbs instead of 12 volt bulbs?

Also the 12 volt battery does POST safety checks before allowing high voltage in your car. This seems wise.