This image shows the terrific job done by the Toyota engineers fitting both the HV and 12 V battery, but also the gas tank (shrunk to 36 l from 42 in the Yaris). All that is encaged by metal protections to protect from side impacts. The 12 V battery is accessible through a removable cover Nice job and worth noting!
That back seat cushion had better be REALLY strong. Imagine kids or teens bouncing on the seat and damaging something in that cage. I'm sure that Toyota has tested the configuration and found it impervious to this type of neglect. Then again, you never know. We will see how well it works soon enough.
Someone help me understand why the Prius C needs the 12v battery. It's lead-acid, is it not? I know that lights and low-power electronics are all 12V, but why is a battery needed for the 12V loads and not just a buck converter for the high-voltage NMH battery?
HV battery gets disconnected when you turn it off. 12v lead acid battery is used to boot up computers to get to READY state.
The accessories -lights, stereo, etc - are powered @12v as well as the start button. There is a voltage converter to recharge the 12V battery. Because it is sealed to be inside the car it is much more expensive to replace even though it has a much lower load than a normal 12V car battery. I'm surprised they didn't find some room under the hood for a less expensive part. That would give normal jump points, so I wouldn't have had to read my manual and hunted with a flashlight when mine died. Does anyone know why its under the seat and not under the hood in the c? I understand it may be for weight balance in the lift back.