12V battery question

Yes there is a way to test it. Any of your major auto parts suppliers will be able to test it for free. Just go in and ask them to test the battery.

The rule usually is to replace the Prius battery when it's over 6 years old. That way you know you're covered

 

Go to Amazon, search for "12 volt battery tester".

I've used a Solar BA5 for over a decade, their current iteration is BA9 I believe. Ancel seems very popular, no experience with it though:

 

As suggested by Mendel - 12 volt digital battery tester. Mendel has an Amazon Canada price

Clore Automotive BA6 and BA9 - $53 an $49 USD respectively on Amazon.com

Clore Automotive Digital Battery Testers

 

Clore link.

 

just get an inexpensive jump pack, and keep it until it no longer recharges

 

Or better yet, a super capacitor jump starter
A supercapacitor for Xmas to jump start a 2009 prius? | PriusChat

 

Wow. Every six years? Our Gen III is over a decade old. I *am* looking into replacing the 12v soonish

 

Battery life for the Prius depends on location and how much heat or cold is exposed. For example in a southern state or northern state might be 6 years and in a state somewhere in the middle 10 years. In Virginia with significant garage time I replaced the original AGM battery at year 8 just as preventative maintenance while had life left. Now after 9 years the second OEM AGM battery tested 288 CCA out of 325 CCA and I plan to keep it until CCA drops to 50%-60%. Hopefully 10-12 years lifespan.

 

I agree fully about environmentals. We get extreme change. Like 50-60 degrees in a few hours on occasion.

The interesting thing about a Prius is: 12v doesn't start the engine so "CCA" is pretty meaningless.

 

That’s why battery lasts that long in hybrids. CCA is still a good indicator for SOH and easily measured by my inexpensive conductance battery tester.

 

Congrats on the decade old battery, it's had a good run. I have a yellow top battery from 2014 in one of my cars, still going strong. I maintain the battery every half year, give it a full charge 1 night. Maybe I can get this one to go a decade

The general recommendation of 6 years is for average users that don't pay much attention to their batteries. It's better to change them out before they fail, as a 12v battery change will normally happen only 1 time if you keep the car for a decade.

 

Yes and no: if the CCA value is dropping I’d say it’s still a good indicator, of a deteriorating battery.

 

That makes sense. My next question is: is any third party battery worth even considering? I've started looking and here is what I see in January 2022:
* All third party batteries seem to come with 2 year warranties, and cost a little over $200
* Toyota TrueStart has a 24+60 month warranty (the latter is prorated)
* My dealer has a $30 off coupon; TrueStart would be $234-30=204 plus tax, installed

This seems like a no-brainer.

 

agree!