How many miles did you get from your 12v battery?

About 35,000 over 55 months. A better measure may be the number of starts, in which case about 3300. Mine wasn't dead but the end was in sight.

No direct substitute is known. Just about the only aftermarket is an Optima Yellowtop. ELearnaid sells them, fully charged, along with a nice installation kit. The kit is highly recommended. Without it you will have to devise your own adapter from the battery to the Toyota cables because the original battery terminals are small.
Prius parts
This approach is fun and the battery should be more durable than the original battery but it will not save much money, if any. Also consider the list of required tools: you will need all of them. If you do not have a bench vise considerable hand strength may be required to disassemble the Toyota positive connector assembly.

The easy solution is to have a dealer do it.

 

I just recently replaced mine with the Optima Yellow top from eLearning.

I had approx. 92,000 miles on the stock 12v battery before I decided it needed to be replaced. I have a feeling I have the largest stereo system of anyone on Prius Chat and as such I beat the hell out of that poor lil battery. I drained it down 5 times during ownership. LOL

 

Four years, 45,000 miles. Had a couple of cases where the car would only partially start -- couldn't drive it and couldn't turn it off until I put a charger on the 12V. With hindsight, I think I would avoid that if possible.

 

Currently at 227,000klm[142,000mls]on my 06 Taxi,original 12v,no issues with starting but might change before end of year although winters in Ireland are mild,sometimes below freezing,but the fact i work nights,car rarely sits in freezing temperatures.Will probably change for OEM battery from dealer,€120,they don't charge for fitting.

 

replaced at 105k on my 02 gen 1 - bought the $105?? oem battery from the dealer, installed myself

 

112,000 miles and counting.

PA P

 

150,000 miles, 62 months and still using the original 12v battery. If you never drain it, it will last a long time.

JeffD

 

56,000 miles and 56 months so far. I do plan on replacing it with a yellowtop when it needs replacement.

 

If you use your Prius as a taxi every day for hours, then your 12V battery is never getting discharged much.

The biggest killer of 12V batteries is discharge. When the voltage drops below certain point, battery starts to die.

So people who do not drive their cars often and even when they drive them, they drive them only for few minutes, are the endangered species on the list of dying 12 V battery.

Second factor is the age of the battery. But it is much less of a factor than discharge. I still have some 12 V led batteries which are over 10 years old and working fine. They are of course kept fully charged with professional charger.

 

Who does free installs?

 

I'm sure there are stipulations in the fine print. I doubt they would install one in a Prius for free or a C4 Corvette (LOL). But I could be wrong. I see this all the time in the car audio world where places claim free installs but you get charged regardless.

I doubt the dealer will install it for free but I wouldn't worry too much. They are quite easy to install, even if you do the conversion. I'd be more than happy to walk someone through the install process, on the phone if need be, just to help them save money and feel more confident in tackling it themselves.

 

South Florida is murder on batteries; 2-3 years is all you typically ge before they die.

I just traded my 2006 with 71,000 miles after 42 months with no sign of weakness.

 

84,000 miles since Jan 06. No problems so far on OEM battery. My wife's Subaru lasted almost 9 years, and I replaced it because I was worried about it, not due to any actual problem.

 

Hardly any more effort involved Rick. You could perform the swap in a snap.

I just like the idea of being able to drain the Yellowtop over and over and not have an issue.