I like my 2012 C, but I'm paranoid about the lead-acid battery

It doesn't look too hard to access (famous last words?). Looking at the Owner's Manual: you take out two fasteners (the easy, push in centre button type) and pull off a small section of the rear seat skirt. Not the whole seat?

 

I'm kind of surprised no-one's taken a photo yet.

 

In other Prius, the 12 volt battery lasts about 4 years then MAY last 8 years. Completely discharging it, leaving a dome light on overnight, etc., usually kills the battery at any age.

Assuming the c has no diagnostic screen, then running the power windows up and down before starting it and comparing the time after starting should be a clue to battery health.

 

This thread has a photo and more information.
Prius C 12V battery | PriusChat
A warning sign is decreasing voltage before starting the car, I'd recommend monitoring this with a ScanGauge or equivalent.

 

I have an Avalon Hybrid. If I still have it when it is 4 years old I am going to buy a new battery whether it needs it or not.

 

the avalon might have a much bigger battery. that would increase lifespan.no jump point under the hood on the C?

 

For checking it's status I'd hook up a multimeter and read it's voltage. Anything around 12.6 or higher it's completely ok. If 12.5 I'd just monitor more frequently. If it's 12.4 or lower you could try hooking up a smart charger, and start window shopping for a replacement.

 

Not in the 2012 - they added it in 2013.

 

sounds like a brain fart.

 

Ah..just don't worry about it.

Yeah, the battery is under the back seat. ( Evidently in a Prius C )

Think of it as a convenient way for YOU to get out of giving other people jump starts.

If you are really nervous about unplanned failure, buy a portable charger and keep it charged and with you.

Again personally? I just wouldn't worry about it. On a two year old Prius, you probably easily have one more year and perhaps two, then you can "start" to worry, and my worrying would "start" with testing the battery at that time.

Until then?

There are a LOT of other things out in the world out to get you.....

 

Yes, and to replace the battery cover you replace 5 fasteners???

 

Sometimes the only way to solve worry and anxiety is to replace the cause of the worry........whether it really needs to be or not.

A good name brand AGM type battery should be MUCH better than the OEM one.
There are threads on here about putting in a slightly larger one even (not sure if putting a bigger one in the C is covered or not).
Replacing the battery should cost you about $150 plus labor if you don't want to do it yourself (maybe another $100).
Make sure the new battery is fully charged.

That MIGHT be a small price to pay for your sanity.

 

Just out of interest, what makes you say that? I have no experience with AGM batteries, but all the factory-installed regular 12V batteries I've seen in Toyotas last an eternity. In my previous car, a Corolla, it had the original battery until the car was 7 years old. I went away for a month in the northern summer, leaving the car behind in our winter and that's what finally took it out. It's been similar with all the other Toyotas in the family or belonging to friends.

 

Get AAA, and forget about it.

 

Mainly because of 2 differences with AGM technology:
No loss of water; the battery is sealed.
MUCH less tendency to sulfate with age, which is what eventually kills most wet cell batteries.
If it is not abused, AGMs are likely to last a minimum of 7 years.

But you don't have to take my word for it.
A quick search for AGM Batteries should get you a mountain of information.

 

I think the OP (if he comes back) should do a dry run, accessing the battery, hopefully ease his fears.

 

I have a little anxiety about the battery in my 2014 Avalon Hybrid but I am not going to worry a lot about it. I am just going to Toyota when the car is 4 years old and have them change it. Maybe you should do the same. That way you probably won't worry so much about it. I used to do some things to a non-hybrid car but I know nothing about a hybrid. I'll just let Toyota take care of it.