what 12v battery will fit and be adequate in '06 Prius?

This is one choice, I currently have had this unit in for about 3yrs.

Exide Edge FP-AGM51JIS

440 CCA; 75 MIN RC at 25A

 

I've read and heard that the 12V is only used to boot the ECU. After that, the HV is then used to start the ICE, so CCA doesn't matter too much.

I went with the Optima on my 2004.

 

the oem is also a good choice.

 

I replaced my OEM with an Optima, it went bad after a short while, did a warranty exchange for another Optima and that one went bad within a year.

I ended up buying an OEM YUASA battery at the dealership. Yes, it was more expensive that the Craptima. But It has given me zero problems and comes with a good warranty too. I second the recommendation for the OEM battery.

 

I went w/ OEM.

• 7 year warranty: 0-24 months 100% Toyota pays, 25-48 months 50% proration, 49-84 month 25% proration.
• Lots of Toyota dealers near me, so a warranty claim would be easy; MUST have original receipt for warranty.

I upgraded the non-smart key 12V battery (35 Amp Hr), to the larger smart-key battery (45 Amp Hr).
Here is the post w/ price, part #s, and pictures: 12V Battery Upgrade: non-Smart Key (35A h) to Smart Key (45A h) | PriusChat

If you are upgrading a non-smart key 12V battery to a smart-key battery, you could save a few buck and simply cut the battery tie down tray to accommodate the larger battery; this will be obvious when you try to fit this larger battery. Discovered this after the fact. You'll also want to have something taking up the space, so the battery doesn't slide forward/backward; ie scrap piece of wood, cut to size, to fill this void, which the proper bracket would do.

 

9 D-cells in a cardboard tube would be adequate for me.

 

How long would there life be in a Prius? Charged at faster than 1C and to voltage of 1,6V per cell.

 

Probably the life of the car.

 

You do remember that (normal) NiMH is 1.2V nominal, 1.5V at 100% charge, and shouldn’t be charged faster than 1C.

 

OEM or Exide seems to be accepted by most as the best option

 

This has been a tongue-in-cheek reference from the beginning. Sorry if you missed the memo.

 

i think 8 d cells would be adequate.

 

Right, but the system voltage of 14.2 would be harder on 8 cells than it would be on 9.

 

good point. what if you disconnect after start up?

 

In this whimsical scenario, I suppose that would be the real-world test (of disconnecting the battery while it's running) that many of us have only talked about. My bets are that you wouldn't notice a thing.

 

you could run some wires to a switch on the dashboard.

 

If I were obsessed with this idea.

 

exactly. it could be the solution to the whole 12 volt battery thing. of course, you'd have to remember to throw the switch when powering down, or else you'd lose some data. i wonder how long 9 d cells will last with the current drain.

 

Not very long, but in my case I don't use acc-mode, only ready-mode, so it wouldn't matter.