Got My Money's Worth Out of this 12V Battery

That battery was in a well used daily driver?

Hang onto it, charge it up with a smart charger every 3~4 months, if you've got the room, as a back up. If you want to check it's overall health, look into Solar BA5 or similar.

 

rare to non existent.

 

Maybe keeping it regularly topped-up is the key, battery nirvana? We're at the other end of the spectrum, the car will often sit idle a day or three. BUT, I've taken to hooking up a smart charger, when ever it's going to be 24 hours or more. I'll post back after the current battery's been in for 10 years, September 2025, lol.

 

I've got 165 k miles on our 2010 with the original 12v battery.

I'll keep pressing my luck .

No whammy, no whammy no whammy.

 

I'd like to say the average life I've seen on these oem batteries, are about 8 to 9 years. 5 year replacement recommendations might be premature for these prius cars

 

All depends on if the battery has experienced a drain or not.

Anytime the wife or kids ride with me in the Prius, I check behind them and ensure the door ajar light is not on.

Already caught it twice on the RX . But closed the door before it drained that 12v.

 

Even after a drain, if you fully charge it within a short period of time, it won't cause much damage. Keeping fully charged by constantly driving the car helps

 

38 miles one way 5 days a week helps.

I use a Battery MINDer 1510 once a quarter for maintenance .

Seems to be effective so far.

 

Too bad you did not put a load in it (High beam, vent fan on high w/ no AC, radio on low), to see what the voltage would be.

 

No maybe about it, it is fact, keeping a lead/acid full charged will keep it in top condition for a long time.

... with an automated maintenance cycle. You can then leave the battery on the charger indefinitely and the charger will switch on and off as required to keep the battery fully charged.

It would have been nice to see what the voltage was with a load on it, but on the face of it, that battery did not need replacing. With your daughter away, is the car just sitting, or is it still being driven regularly? If it is just sitting, you might consider keeping the 12 V battery on a maintenance charger just so it stays in top condition.

 

I wonder off-and-on about the viability of a solar powered 12 volt battery maintainer. From a few years back, a very bright fellow's take:

Guide: Installing a solar panel on the HCH-II (step-by-step) | CleanMPG

And just googling:

How Do I Charge My Car's Battery with Solar Panels ? In Depth Review | Review of 12 Volt Solar Battery Chargers

Some third gen Prius had the "Solar Roof". Something like that would be great for 12 volt battery maintaining?