Replace 12v battery?

lagreca · 07-17-2007, 03:08 AM

It seems that the stock 12v battery may be a bit small in terms of the time you can run your radio, before it dies.

Is it possible to replace it with a higher ah battery?

What is the maximum size batter you can put in?

What about posts location and size?

Does anyone know of a specific battery that will replace the stock one?

lagreca · 07-18-2007, 02:02 AM

<div align="left">While looking at other information, ran into this site:

http://www.techno-fandom.org/%7Ehobbit/cars/prius-12V/

However, I'm still wondering if anyone has had to replace their 12v battery yet, and if so, what model did they use?</div>

David Beale · 07-18-2007, 01:26 PM

Just had a look at an Optima yellow top in size 51. It looks like it will just fit, but the terminals are backwards and the wrong diameter. So some work would be needed to use it. Probably doable though.

abq sfr · 07-18-2007, 02:27 PM

<div class='quotetop'>QUOTE(lagreca @ Jul 17 2007, 01:08 AM) [snapback]480113[/snapback]</div>

Quote:

It seems that the stock 12v battery may be a bit small in terms of the time you can run your radio, before it dies.

Is it possible to replace it with a higher ah battery?

What is the maximum size batter you can put in?

What about posts location and size?

Does anyone know of a specific battery that will replace the stock one?
[/b]

If I were that worried, I'd carry one of those self-contained jump start units that Costco has for around $40, it might even store under the trunk floor. Even if you replaced the stock battery with a larger capacity one that would fit in roughly the same space it would probably only run 20% longer before running down... but it would still run down eventually. I run a 50-watt ham radio transmitter off of that little battery, and am not too worried about the battery draining. As long as you have the ready light on the dash, if it you drain the 12v too low it will get charged up again anyway. Remember the 12v battery does not need to provide that much amperage... it mostly just needs enough juice to boot the computer.

dogfriend · 07-18-2007, 02:53 PM

<div class='quotetop'>QUOTE(abq sfr @ Jul 18 2007, 11:27 AM) [snapback]481054[/snapback]</div>

Quote:

If I were that worried, I'd carry one of those self-contained jump start units that Costco has for around $40, it might even store under the trunk floor.[/b]

Yep, I bought one from WalMart for $35. It is a Black and Decker brand, but it is actually made by Vector and is also sold under that brand (possibly even cheaper).

I think it would fit under the deck lid, but it would have to be layed down on its side; the instructions recommend keeping it upright. I store mine on the right side of the cargo area above the 12v battery. I have it bungie corded to the cargo tie down, so it won't become a projectile, and having it visible reminds me to check the charge level once a week or so.

Another advantage is that you can use it to jump other vehicles without involving your Prius.

auricchio · 07-18-2007, 04:26 PM

If you're going to listen to the radio or use other accessories for a long time, just put the car into "ready" mode as if you're going to drive away. The traction battery will keep the 12v battery charged, and the ICE will start if it needs to charge the traction battery.

In most cases, the ICE will never need to start, because the traction battery will be able to keep the 12v system charged for a long time.

9G-man · 07-19-2007, 12:01 AM

Just put your car into IGN-ON mode and you can run your radio about forever. The HV battery will discharge, but it will take a long time. Plus, the HV battery S.O.C. will be displayed on the MFD, so if it gets too low, either shutdown, or go to READY mode and let the ICE recharge it.

Don't think I'd sit around in READY mode unnecessarily, or unattended. Someone could bump the shifter and then the car could easily move.

dogfriend · 07-19-2007, 12:12 AM

<div class='quotetop'>QUOTE(9G-man @ Jul 18 2007, 09:01 PM) [snapback]481387[/snapback]</div>

Quote:

Don't think I'd sit around in READY mode unnecessarily, or unattended. Someone could bump the shifter and then the car could easily move.
[/b]

They have to step on the brake pedal and bump the shift lever at the same time. Otherwise it will just beep.

auricchio · 07-19-2007, 12:51 AM

Press the brake pedal, move the shifter, and release the parking brake.

Not something that would happen accidentally: there are three separate actions, requiring two feet and one hand.

9G-man · 07-19-2007, 08:39 AM

Does anyone recall "Unintended Acceleration". It almost put Audi out of business in the early '80's. And it required 4 seperate actions. The three you mentioned and 1 more......Stupidity.

The main point here is IGN-ON mode will accomplish what READY mode will for extended radio listening without potential for problems. And it eliminates one unnecessary ICE start cycle. The first one.

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07-17-2007, 03:08 AM	#1
lagreca Junior Member Join Date: Jun 2007 Location: San Diego Posts: 28 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	It seems that the stock 12v battery may be a bit small in terms of the time you can run your radio, before it dies. Is it possible to replace it with a higher ah battery? What is the maximum size batter you can put in? What about posts location and size? Does anyone know of a specific battery that will replace the stock one?

07-18-2007, 02:02 AM	#2
lagreca Junior Member Join Date: Jun 2007 Location: San Diego Posts: 28 My Car: Package: Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	<div align="left">While looking at other information, ran into this site: http://www.techno-fandom.org/%7Ehobbit/cars/prius-12V/ However, I'm still wondering if anyone has had to replace their 12v battery yet, and if so, what model did they use?</div>

07-18-2007, 01:26 PM	#3
David Beale Senior Member Join Date: Jul 2006 Location: Edmonton Alberta Posts: 1,532 My Car: 2007 Prius Package: B Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Just had a look at an Optima yellow top in size 51. It looks like it will just fit, but the terminals are backwards and the wrong diameter. So some work would be needed to use it. Probably doable though.

07-18-2007, 04:26 PM	#6
auricchio Senior Member Join Date: Mar 2006 Location: Cambria, CA, USA Posts: 853 My Car: 2006 Prius Package: #8 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	If you're going to listen to the radio or use other accessories for a long time, just put the car into "ready" mode as if you're going to drive away. The traction battery will keep the 12v battery charged, and the ICE will start if it needs to charge the traction battery. In most cases, the ICE will never need to start, because the traction battery will be able to keep the 12v system charged for a long time.

07-19-2007, 12:01 AM	#7
9G-man Senior Member Join Date: Jul 2005 Location: Atlanta, GA Posts: 784 My Car: 2007 Prius Package: #5 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Just put your car into IGN-ON mode and you can run your radio about forever. The HV battery will discharge, but it will take a long time. Plus, the HV battery S.O.C. will be displayed on the MFD, so if it gets too low, either shutdown, or go to READY mode and let the ICE recharge it. Don't think I'd sit around in READY mode unnecessarily, or unattended. Someone could bump the shifter and then the car could easily move.

07-19-2007, 12:51 AM	#9
auricchio Senior Member Join Date: Mar 2006 Location: Cambria, CA, USA Posts: 853 My Car: 2006 Prius Package: #8 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Press the brake pedal, move the shifter, and release the parking brake. Not something that would happen accidentally: there are three separate actions, requiring two feet and one hand.

07-19-2007, 08:39 AM	#10
9G-man Senior Member Join Date: Jul 2005 Location: Atlanta, GA Posts: 784 My Car: 2007 Prius Package: #5 Nominated 0 Times in 0 Posts TOTM Awards: 0 Friends: 0	Does anyone recall "Unintended Acceleration". It almost put Audi out of business in the early '80's. And it required 4 seperate actions. The three you mentioned and 1 more......Stupidity. The main point here is IGN-ON mode will accomplish what READY mode will for extended radio listening without potential for problems. And it eliminates one unnecessary ICE start cycle. The first one.