Toyota RAV4 Forums banner

1 - 4 of 4 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
I purchased, and am very happy with, a 2016 RAV4 hybrid. I've had a few questions that I'm completely unable to find answers to, so I thought I'd ask them here. I'll post them separately in case someone can answer only one of them.

First, how is the 12V system configured? I understand there's a separate 12V battery, pretty standard stuff for most automobiles. It makes sense so they don't have to re-invent the wheel in terms of light bulbs and accessories alone -- standard light bulbs, radios, etc. will all work. But how is it kept charged? I'd assume it's a standard alternator run off the ICE engine, is that correct? Is that alternator separate from the alternator used to charge the hybrid battery?
 

·
Registered
Joined
·
1,992 Posts
Suggest you read up on the Toyota hybrid system, search for Prius information.
The Rav4 has 3 motor-generators that power everything.
 

·
Registered
Joined
·
132 Posts
The three motor generators (MG1, MG2, and MG3) are both alternators and motors. There is no dedicated alternator.

These charge both the high voltage traction battery and the 12VDC auxiliary battery. The auxiliary battery is not your typical lead-acid battery found in any car. It's an AGM battery (absorbed glass mat) which is more durable and safer than lead-acid, but doesn't allow the kind of current you need to drive a starter motor. This means you cannot use it to jump another car. I mean, you could, but it would require leaving your car "on" for 5-7 hours while it trickle charges the other car. :)

The reason main why there are two separate batteries is because you wouldn't want accessories to drain the traction battery below it's minimum threshold (around 40%) because without the traction battery, your car is dead and it greatly reduces the life of the traction battery. You cannot recharge the traction battery without a special charger supplied by Toyota. Also, the voltage of each battery cell in the traction battery varies slightly depending on the charge level, which is fine for motors, but bad for electronics. The auxiliary battery will put out 12VDC consistently, as long as it stays fully charged.
 
1 - 4 of 4 Posts
Top