What kind of 12v battery do I need for a 2007 Prius?

Sometimes the cheap person spends the most money.

IMHO, you cannot force the wrong battery into this spot. You will have to spend the bucks and get a battery that really fits, otherwise you at minimum are going to spend a lot more to get it to work, or you are going to risk life and limb because it does not work but you forced it to work -- after a fashion.

Friends, credit cards, collecting returnable pop bottles. GO for the cheapest battery that DOES FIT if you have to. DO NOT try to fit an elephant into a mouse house..

 

If you never drive with anyone else in the car, the only person at risk is yourself.
So if you do not care about your life, all is well.
(you could mount the battery outside the car, but that is a huge modification)

 

My wife bought a 1972 VW beetle 46 years ago with a non-vented, not even AGM battery, under the backseat. The neighbor owns it now, going on about the 3rd or 4th engine. Battery hasn't killed anyone yet...

 

I have edited and updated my post # 20. Please re-read it to get the answer, which is no.

I'll repeat part of it here for emphasis.

$105 for the improper wet cell Walmart battery versus $154 for the correct Bosch AGM VR battery installed at Pep Boys. The Bosch battery is the proper choice between these two.

Also, the safety is an issue. The Prius should have an AGM Valve Regulated battery and the hose should be hooked up to the vent hole for safety (in case hydrogen, or worse, very poisonous hydrogen sulfide is vented out in a high pressure failure situation).
The Walmart BCI Group No. 51 battery is not an AGM VR battery and does not have the proper vent hole to attach the hose to.
This battery is a standard wet cell type, with free flowing liquid sulfuric acid electrolyte inside it.
The Walmart battery is not safe for regular or long term use in a Prius, long term being more than a day or just for a very short term emergency.

If you buy the Walmart battery, you are wasting $105. Spend $49 more and get the correct and safe Bosch battery.
If you buy the Walmart battery, you are playing with fire ... or in the worst case, your life. I obviously do not recommend using it in a Prius.

"In June 2016, a mother and her daughter were found deceased in their still-running Porsche Cayenne SUV against a guardrail on Florida's Turnpike, initially thought to be victims of Carbon monoxide poisoning. Their deaths remained unexplained as the medical examiner waited for results of toxicology tests on the victims, until urine tests revealed that hydrogen sulfide was the cause of death. A report from the Orange-Osceola Medical Examiner’s Office indicated that toxic fumes came from the Porsche’s battery, located under the front passenger seat."

If you want to take this kind of chance, even if remote, to save $58, it seems foolish to me. But it's your choice.

Just re-checked the Bosch price at Pep Boys. It used to be 25% off, but now it's only 20% off.
The current price is $163 installed. So the Bosch is $58 more than the Walmart. Or $47 more if you install yourself and return the core.
Bosch 51-440BAGM 45Ah 29lbs (13Kg) 4-Yr Replacement Warranty - $163 (190 - 38 + 11) installed, $167 (190 - 38 + 15 refundable Core) in store ($152 after core return) (Pep Boys)
(https://www.pepboys.com/product/details/647478)

 

Hydrogen fires are scary enough under the hood, but the Prius has the battery in the passenger compartment.

How to Avoid Battery Explosions (Yes, They Really Happen) - latimes

 

keep your windows rolled down, and try not to get rear ended.

 

How do you know the battery is bad? When was it last replaced? Has someone charged it and done a load test? Worth getting it tested first.

 

you can get a free battery test at most auto parts stores. they might even charge it.

 

The Porsche battery is much stronger than a Prius battery. It has to be to operate the starter. And there is an alternator in the Porsche that can put out much more power than the inverter in a Prius.

The typical failure mode of an inverter is zero output. That's not going to boil any battery.

My take is that a rare failure mode on conventional cars is being spun as extremely dangerous on a hybrid. The Prius failure modes are different, and need to be considered to get a reasonable danger rating. The danger is non-zero, but vanishingly low. I'd be a lot more scared of numerous other things before battery offgassing. The Prius battery is fairly isolated in the trunk area, behind a body panel. As I recall, there is an exit vent in the battery space, which vents that entire space, not just the battery tube.

As for the current Prius battery, I don't think there is enough evidence yet to indicate that replacing it will change anything. The first thing to check is the resting voltage with the car off. If it's less than 10 volts, it's clearly a problem. Less than 11 could be, but probably not enough to block getting to Ready. One problem that prevents getting to Ready is a bad/improperly adjusted brake light switch. If the battery has been reverse jumped, there would be fuses blown that have to be replaced.

 

Have you googled "12v battery for 2007 Prius"?
By the way, Pep Boys has discontinued the Bosch batteries and replaced it with a Champion that includes a 4 year full replacement warranty for $10 cheaper than the Bosch. Pep Boys also charges $10 to install in a Prius.

 

I get the impression that the OP's idea of "short term" is not going to be short term.
Cheaper batteries will not fit. And they don't have the proper vent safety tube.
It is foolish to spend $100 for a battery when a $155 will get the correct battery.

 

IF your battery tests bad and you are really strapped for cash, you might be able to get by with an AGM "Sport" battery. I don't recommend this, but if you don't have the money, it might be a short term fix.

This one is $64 plus tax. It's dimensions are smaller so it will fit in the battery compartment. But it's also only 18Ah so it's just under half of the capacity of the Optima (38Ah) and even less compared to the other batteries which are around 45Ah.
You'll have to avoid using ACC or IG-ON modes very much, say for listening to the radio.
Only use OFF and READY modes.
The terminals have the correct placement (+ on left). But it has "A" or NB type terminals so you will have to kludge a safe connection from the cables to the battery.

This is an AGM battery so the acid electrolyte is absorbed in the glass mat and not free flowing as a wet / flooded cell is.
I didn't see a vent hole to connect a hose to, so that is still a risk.

At Pep Boys:
ProStart AGM Power Sports Battery
LT20-4 18Ah (C/10) 13lbs (6Kg) + on Left A / NB posts (6.4mm hole on top and side of post) $64 (90 - 33 + 7 Core) (Pep Boys)
(https://www.pepboys.com/product/details/427702)
(https://static.pepboys.com/images/productImages/75986100/LT20-4.pdf)

 

I understand not having cash.

I truly do. I was the one in college who was continually picking fruit from street trees. I ended up in such dire straits at one time that I ended up eating a partial bag of rye grass seed that was stored in the garage of the house I was staying in (it was one of those deals, absentee landlords rent a house to college students -- there were four of us, each paying XX per month).

Problem was, I thought rye was healthy -- they made bread from it right?

However, I did not know they treated the seed with fungicide to kill the ergot that grows on rye and causes certain acids to form....google Sandoz, ergot, hoffman if you need details.

I was so sick for several days, I did not have to worry about eating.

Again, there is a point to saving money and then there comes a point when it becomes dangerous. At the time, I would have been better off not eating for a few days than trying to save money eating the seed.

 

Sorry to resurrect this thread. I'm not real active here on Priuschat due to interests having shifted to EVs but my Optima Yellow Top I bought and installed from eLearnAid ( Toyota Prius 12 Volt Auxiliary Battery with install kit for 2004 + including Plug in) into my 06 Prius is from Feb 2011 and is starting to go, judging by my Optimate 4 charger's behavior. I already changed the cables and posts so the larger style as part of that kit. I think in 2011, there was no pencil post version of the Yellow Top yet.

I'm really confused by the verbiage on Pep Boy's product page for the Bosch Part #: 51-440BAGM | SKU : 647478. It says

I'm well aware of the 2 different-sized OEM batteries depending on whether the gen 2 Prius came with or w/o SKS. Mine DEFINITELY has SKS (I have package NL which has every option except leather). Does the above Bosch battery require me to buy the above tray and hold down or is it compatible w/the hardware (tray and hold down) SKS-equipped Priuses came with?

Just trying to be prepared before I call Pep Boys. I think I'd rather have them install it...

 

I bought the Bosch from Pep Boys online, but when I picked it up, it was more than six months old as they have discontinued them. The Champion brand they now carry has the wrong size terminals. Ended up buying a genuine Toyota battery for $25 more.

 

Here's a genuine OEM Toyota parts listing page showing battery options for your model. You can add your VIN on the page to narrow down/filter the battery options for your vehicle. 2007 Toyota Prius Battery & Battery Cable - Toyota Parts Deal . Hope this helps