12V Battery Replacement-- A Preemptive Strike

I just dug down to our (OEM) battery, since it's voltage has dropped a bit, and recorded this info from the label on top:

S46B24R GS YUASA

Then searching yields this site:

Rakuten: Toyota Prius-only GS Yuasa battery S46B24R (HJ)- Shopping Japanese products from Japan

where they say capacity is 36 Ah

The Optima 8171-767 DS46B24R does show as 38 Ah here:

8171-767 DS46B24R - OPTIMA Battery

Maybe varies with country, and/or generation?

 

There are two sizes of OEM batteries fitted to the Prius in the US depending on the entry system used
"36 AH or 45 AH". Only the larger battery appears to be fitted in the UK.
This is why on some vehicles it is required to change the battery carrier when fitting alternative batteries such as the Optima or the Exide to take extra larger proportions of the "higher capacity" battery. The Optima is larger because it waists so much space (about 25%) with it's circular cell construction.

John (Britprius)

 

Just did my first 12v replacement of my 2007. I'm fairly certain this was the same battery that's been in the car since the beginning. I never got a reading higher than 11.9v, and from the getgo I got 12.4v. After driving for a bit, it hit 13v, so I think it's working fine.

I experienced two gotchas:

1) The vent tube wasn't long enough with the vent hole on the Optima. I had to run to my neighborhood Ace to get a similar and longer tube. It cost 21 cents, so easy on the wallet.

2) Instead of a 10mm hex bolt, I had a screw on the vent duct (the one that's farther in, against the side of the car). Not a gotcha, just a difference that none of the instructions mentioned.

The whole thing took more than an hour, but I'm slow. And it freaked me out that there were sparks and smoke when you disconnect and reconnect the negative terminal, but as it turned out, it was all for show.

 

I would bet if you removed the battery and the battery carrier you would find the 10mm bolt in the bottom of the well.

 

Thanks to all who contributed to this thread - the videos and advice made the job go quite well.

When I read about the problems associated with trying to re-install the vent duct, especially the sidewall bolt, I tried a different tack. Instead of removing both the sidewall bolt and the floor bolt attaching the vent duct to the body, I only removed the floor bolt. By moving the vent duct aside a little, and tilting the old battery forward (toward the front passenger seat) as I lifted it out, I was able to get it out. The new battery went in tilted the same way the old one came out. Since both batteries are sealed units I didn't have to worry about acid leakage when tilted. And I avoided the dreaded vent duct sidewall bolt re-installation.

I called the dealer and they had a replacement for $210, but after looking around a little I went with this Duracell from BatteriesPlus: SLI51PAGM Duracell Ultra Platinum AGM Battery
- 2004 to 2009 L4 1.5L Smart Key 325CCA - Prius - Toyota - Car and Truck - Batteries Plus
It cost $170, has a 4 yr. full replacement warranty, and there are BatteriesPlus stores all over the country. Up till now I had no idea that Duracell made car batteries. I will post if I have any problems with it, but it matched the OE perfectly and has done well for the first few days. I have the sense that my mpg's may have improved.

Ken

 

It is just a brand name. The car batteries likely have NOTHING in common with the flashlight batteries except the name.........including the company that actually makes each different type.

Did you fully charge your new battery before installation ?
If not, now it not too late.

Another Ken

 

>> I have the sense that my mpg's may have improved.

Not to mention the increased horsepower and improved stereo quality. Chicks dig it more, too.

 

(Another) Ken, I used a trickle charger to maintain current while changing the battery and left it on to charge it. The battery did have a pretty good charge right out of the box.
Yakoma, Those same things happen when I wash & wax the car, too!
Ken

 

I have a 2010 Toyota prius and after approx. five and half years and 52000 miles on it, the auxiliary battery failed.
Total cost was $275 ($200 parts& tax for 12v aux. battery and 1 hour labar charge@$75). I inquired the cost of 3rd party Optima battery at Autozone and it was quoted to be $229 excluding tax.

 

OK, I am foolish or ?
My original 07 Prius Touring battery (8 years, 110k+ !) came out fine, but the new Optima Yellow Top did not fit, by a long shot. Worse, there is no adjustment and there is no larger battery tray available for the larger battery according to the dealer. Any advice?

Many apologies, tried to delete this to no avail, so here is how I made the new battery work, it was over an inch longer than the original:
I removed the battery tray, and bent the positioning tab up with pliers so that it did fit the slot it originally was in anymore. Then, pushing the tray forward as far as it will go (this only gains a tiny, crucial, amount because the tray holes are slightly larger than the bolts, not slotted as one would expect to see if the tray was meant to be adjustable) I tightened the bolts down. This allowed the battery to fit very snugly, had to fist bump it down into place. With the battery clamp reinstalled, I am comfortable that the overall mounting is secure.

Glad I took this on, and many thanks to customer service at the supplier for excellent support.

 

What is the model number of the GS Yuasa battery that you removed?

Return the Optima and buy the correct battery.

 

Clearly you have the wrong battery.

 

No, got the one I needed, and yes it does fit. Had to do a mod on the battery bracket to make it work, not too bad once I knew exactly what to do. My mistake, I was indeed foolish! Yet happy with how this turned out. I will attempt to delete the thread so as not to mislead, my bad!

 

I've replaced the battery twice. Once with a Toyota and once with an Optima. Never had a fit problem. Never needed to do any kind of modification. Any pictures of your fit problem and/or mod?

 

Apparently your car does not have the Smart Start/Smart Entry system, if the original 12V battery was shorter than the Optima. Please find the model number on your original 12V battery and post it. The correct GS Yuasa battery for Prius with Smart Start/Smart Entry has model number S46B24R.