Prime 12v Auxiliary Battery

Any lead-acid battery of the size known as H4, LN1, or 140R will do; an AGM battery, needed for older Prius models, is not required. (This has been discussed at length in many previous threads.)

 

or you can make your own concoction with adjustable brackets and new terminal connectors

 

I've been searching up and down the PriusChat forum for these discussions, but I think I'm using the wrong keywords or something. Could I get pointed to those threads please?

I got a 2018 Prius Prime and am looking to replace the 12v auxiliary battery as well. Would it hurt to upgrade to AGM? or is it a waste of money?

 

I won't use anything BUT AGM in any of my vehicles, including lawn mowers, because I think it is better technology and is a better value overall.
YMMV.

 

For starters phone the dealership*, see what they recommend, and get a quote. Then check online at any of the automotive retailers selling batteries, those that have a website dialogue where you enter the car's stats, and it shows what they've got that's compatible. Read reviews.

Or go to parts.Toyota website (Toyota USA official parts site), enter your vehicle stats, and you can see what the spec'd battery is, the MSRP, and nearby dealership "street" prices. For me (just over the border in BC) it shows this:


2018 Toyota Prius Prime Vehicle Battery - 00544H4052470 - Genuine Toyota Part


With suggested retail $180~ USD, and nearby-to-me dealership price no lower.

AGM's are required if the battery's in the passenger compartment; so I wouldn't bother. FWIW, the stock battery, while not an AGM, is still pretty pricey.

* If nearby, in your location in United States of America