12 v battery

toolbox · 10-09-2004, 05:24 PM

anyone hip on what the 2nd 12v battery is for. I was told it controls all pcm and engine functions only... and that the hybrid battery controls everything else (ac,stereo,security,plus drive motor functions) can anyone confirm this.

DaveinOlyWA · 10-09-2004, 08:51 PM

nope stereo is 12 volt im sure

bruceha_2000 · 10-09-2004, 09:09 PM

<div class='quotetop'>QUOTE(toolbox\";p=\"44251)</div>

Quote:

anyone hip on what the 2nd 12v battery is for. [/b]

What second 12V? I thought there was only 1, behind the right rear tire.

toolbox · 10-09-2004, 11:17 PM

bah i miss worded it... the second battery or 12 volt not second 12v...

DaveinOlyWA · 10-10-2004, 03:41 AM

as i understand it, the traction battery pretty much does the traction and nothing else. the 12 volt battery performs all the same functions of any 12 volt battery in a regular car except starting the engine of course.

the reason why a normal car has such a large battery is to have the power to crank the engine. eliminate that need and there is little reason to have a large battery.

victor · 10-10-2004, 06:35 AM

Im not 100% sure, but I think you will find that the NV system also provideds 12V for accessories etc via an inverter after the car has started, in addition to re-charging the 12V battery.

DaveinOlyWA · 10-10-2004, 12:00 PM

well yes technically you can say that the inverter does supply the electricity for everything. as with all cars the inverter provides power directly to 12 volt sources and charges the battery at the same time. howver for surge suppression, voltage control, etc, the battery is used as a balancing load.

but your question is asking what the battery is used for and when the car is not running that is what its used for. if you run the accessories too long, the 12 volt battery will not take power from the traction battery, it will die. there are many many posts here detailing dead 12 volt batteries. being cheap, expendable, and for eliminating the danger of draining the traction battery through neglect is the whole reason the 12 volt battery is there.

if the inverter did the job all the time, then why have the 12 volt battery at all?? why not just make a bigger traction battery? well the answer is simple. the two systems are not electrically connected when the vehicle is not running or at any other time.

i dont understand your questioning here. are you suggesting the 12 v battery is extraneous?? i can assure you it is not. the two batteries provide separate irreplaceable functions and are both very necessary.

victor · 10-10-2004, 12:09 PM

Quote:

if the inverter did the job all the time, then why have the 12 volt battery at all?? why not just make a bigger traction battery? well the answer is simple. the two systems are not electrically connected when the vehicle is not running or at any other time.

I didnt quite say that, I said after the car has started. I base this on something I read about the electrics in the Prius and the attached PFD.

If you look at it , both the HV and the auxillery batteries feed into the inverter via another box I can translate.

DaveinOlyWA · 10-10-2004, 12:18 PM

ok the traction battery will not power anything the 12 volt battery powers at any time.

victor · 10-10-2004, 12:52 PM

Quote:

ok the traction battery will not power anything the 12 volt battery powers at any time.

Is that definative then ???

If you want I can email you the circuit diagrams and you can take a more detailed look. As I said originally, Im not 100% sure, but I understand that... Take a look at the PDF above.

I could be wrong, often am.

10-09-2004, 05:24 PM	#1
toolbox Join Date: Sep 2004 Location: St. Louis Posts: 72 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	12 v battery anyone hip on what the 2nd 12v battery is for. I was told it controls all pcm and engine functions only... and that the hybrid battery controls everything else (ac,stereo,security,plus drive motor functions) can anyone confirm this.

10-09-2004, 11:17 PM	#4
toolbox Join Date: Sep 2004 Location: St. Louis Posts: 72 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Re: 12 v battery bah i miss worded it... the second battery or 12 volt not second 12v...

10-10-2004, 06:35 AM	#6
victor Join Date: May 2004 Location: Gilching Bavaria Germany, & Drapanos, Crete, Greece. Posts: 414 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Re: 12 v battery Im not 100% sure, but I think you will find that the NV system also provideds 12V for accessories etc via an inverter after the car has started, in addition to re-charging the 12V battery.

10-10-2004, 12:00 PM	#7
DaveinOlyWA Opps !! I Did it Again!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 9,661 My Car: 2006 Prius Package: #4 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 5	well yes technically you can say that the inverter does supply the electricity for everything. as with all cars the inverter provides power directly to 12 volt sources and charges the battery at the same time. howver for surge suppression, voltage control, etc, the battery is used as a balancing load. but your question is asking what the battery is used for and when the car is not running that is what its used for. if you run the accessories too long, the 12 volt battery will not take power from the traction battery, it will die. there are many many posts here detailing dead 12 volt batteries. being cheap, expendable, and for eliminating the danger of draining the traction battery through neglect is the whole reason the 12 volt battery is there. if the inverter did the job all the time, then why have the 12 volt battery at all?? why not just make a bigger traction battery? well the answer is simple. the two systems are not electrically connected when the vehicle is not running or at any other time. i dont understand your questioning here. are you suggesting the 12 v battery is extraneous?? i can assure you it is not. the two batteries provide separate irreplaceable functions and are both very necessary. __________________ My 2006: Last tank 463.1 miles @49.2 pump (49.4 computer) 4.22 cpm winter mpg 50.70 summer mpg 54.59 lifetime: 33,038.3 miles 52.79 mpg pump (54.04 mpg computer) 5.74 cpm My 2007 Zenn Driven 5945 miles, 2.01 cpm/ 105 mpg (at $2.05/gal), 4.04 miles/ Kwh Savings over my Prius $302.66 The Corolla...573.26 The REAL SAVINGS from not driving Corolla 657.39 +Prius= 958.18 (excludes maintenance costs...would be unfair to ICE vehicles) My Plate: DUALPWR (Dual Power)

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10-09-2004, 08:51 PM	#2
DaveinOlyWA Opps !! I Did it Again!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 9,661 My Car: 2006 Prius Package: #4 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 5	nope stereo is 12 volt im sure

10-10-2004, 03:41 AM	#5
DaveinOlyWA Opps !! I Did it Again!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 9,661 My Car: 2006 Prius Package: #4 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 5	as i understand it, the traction battery pretty much does the traction and nothing else. the 12 volt battery performs all the same functions of any 12 volt battery in a regular car except starting the engine of course. the reason why a normal car has such a large battery is to have the power to crank the engine. eliminate that need and there is little reason to have a large battery.

10-10-2004, 12:18 PM	#9
DaveinOlyWA Opps !! I Did it Again!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 9,661 My Car: 2006 Prius Package: #4 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 5	ok the traction battery will not power anything the 12 volt battery powers at any time.