Diagnosing Cheap 3rd Gen Buys

well done!

 

"Powersports batteries are way cheaper, but will require adapters."

SURE, go CHEAP as you can on that battery! It's only one of the most critical operating components of your Prius...

 

Don’t let the guy who posted rear back up guidelines are much more important than clean hybrid fan CEL see your comment

 

AFAIK, powersports batteris are not AGM. The Prius charging system is designed for AGM batteries and may not do a good job on a powersports battery.

 

AFAIK the main criteria for using AGM is because they emit little or no gas. Any that is emitted is through a vent that is compatible with the Prius' exhaust vent tube.

 

Thought the 12v tells the hv battery to fire up the vehicle so quality just has to be at a certain standard and not required to be that good of a battery with deep cycle capabilities.

 

I have two battery chargers with separate settings for AGM batteries.

 

"an odd bit of automotive mystery that one is."
Indeed, and the producer has presented no (none) actual data on how it performs. Everything is anecdotal...

 

My CTEK chargers recommend charging at the slightly higher voltage settings, only for 6-pack style AGM's, not the rectangular case AGM's, the OEM Yuasa for example.

Which came first, chicken or egg? Fourth gen has relegated the battery to the engine bay, and is using conventional lead-acid.

 

Good logically presented info. I'll expand on a few things.

Yes, the first thing you need is for the battery to be 12V, the second thing is for it to fit.

Two distinct safety issues here. Don't forget about the second one.
1 - any battery can vent gas - hydrogen or hydrogen sulfide. The latter is poisonous; the former not so good either in the presence of oxygen and an ignition source.
2 - a flooded lead acid battery has the electrolyte in the form of sulfuric acid. Any passenger car will be designed so that in the event of an accident, the car will be as safe as possible, so considering that the battery might be punctured and spill liquid acid throughout the car is something they avoid by design. AGM batteries do not have liquid acid that will spill and spray when the case is punctured.

True. A voltmeter on the battery while the car is turned on will confirm this. But all car batteries are charged at about 14.x V from the alternator, so any difference here is not dramatic.

Well yes, if you run accessories while the car is off. Something that can easily be avoided if it's actually a concern. And no matter what battery you have, some amount of running accessories with the charging source of will kill it below its ability to get the car running or "ON."

As I understand it, the function of the 12V battery in the Prius is far less critical that in a regular car. In a regular car, it needs to provide sufficient current while maintaining voltage for enough time to get the engine started (for example, supplying the starter with 300+ Amps at 10+ Volts for 10+ seconds), otherwise you are stuck. In the Prius, it needs to power up some circuits and close the relay to engage the high voltage battery. Critical, but that seems to be far less demanding that in a convential car. Once the traction battery is engaged, it will use the DC-DC converter to maintain 14.x Volts at the battery, at which point the 12V battery is mainly a buffer to voltage fluctuations while running the car's 12V accessories (virtually everything outside the powertrain).

I would not even consider a scooter battery, etc. Plenty of legit automotive batteries to choose from. I have an Optima 34/78 Red Top in my 2012 v. I mainly put that in as an experiment soon after getting the car, and since I just transplanted it from a little-used car in my fleet.

That PDF looks like BS to me. Aftermarket production of a critical Toyota part. Supported with 7th grade science terms and handwaving (e.g., equations that don't actually support what they're trying to say, but are used as props). No way I believe that Toyota's part would be so deficient, unless everybody else tells me the Toyota part sucks. Have not heard that.

 

Mod eh? Rumor has it that a feller started his prius with d cell batteries. I don’t know what else will be cheaper than that.

 

Check with your automotive retailers. Up here Canadian Tire is pretty much it, I think. I should check Napa too. I suspect phoning up the dealership, the price would be over $300 (CDN) by now (haven't checked in a few years), so this is a "bargain":


Addendum: Napa Canada seems out-to-lunch, can't even access their site. Considering my recent shopping experiences there, I really think they're about to fold.

 

Duralast Platinum Battery 46B24R-AGM Group Size 46B24R 410 CCA

AGM Toyota Prius Auxiliary Battery | Prius 12V Battery

https://www.napaonline.com/en/p/NBP9851P?partTypeName=Battery+-+Automotive&keywordInput=12v+battery+fo

TRYING to get a price for a Toyota battery, but the site won't let me look it up...
Those are the greatest of batteries, but you want cheap, these are cheap...

 

Have no ideal why it posted so many times!

 

Have no ideal why it posted so many times!