2017 Prius Prime Advanced replacement battery

I show this battery available from Amazon for 122$ includes 10% coupon. Measurements seen identical to the H4 listed at Walmart. DIY install seems doable. Any reason why it shouldn’t ?
Thanks, Matt
UPLUS BCI Group 140R Car Battery, AGM-L50-UP Maintenance Free 12V 50Ah Premium AGM Batteries H4 LN1 Automotive Battery, 570CCA, 120RC

 

Still going strong 2.5 years later. Both Prime are approaching 7 years with their original 12-volt.

 

My Toyota batteries have never failed

 

Here in New Hampshire, I've had no 12V problems with my 2017 Prime purchased in Sept 2017. But an ex girlfriend who bought one in December 2017, recently had her 12V suddenly die after 70 months, so I decided that replacing mine (after 74 months) was a good idea. Especially because I'd bought a replacement a year ago, and putting it in the car will save me from monitoring and maintaining it at home.

Due to a habit of car camping for a month at a time, a couple of times per year, I wanted more reserve capacity than the stock battery's 90 minutes. So, my replacement is an AC Delco Group 47 AGM with 115 minutes reserve. It required minor surgery to remove the front and rear of the plastic battery tray, to fit. Likewise on those two sides of the battery itself, I trimmed off the mounting flanges flush. Obviously, I was very careful to not cut it below flush, which would have ruined the battery. I was also careful not to cut the wiring below the plastic battery tray. With my Skil 12V cordless oscillating multitool, I felt like a brain surgeon for the 2 minutes that the 4 surgeries combined, took me.

I got the battery online at Summit Racing. So far, so good. Do I recommend the larger battery for average folks? No, just if you specifically need additional reserve capacity. The stock Group 140R size is plenty for normal usage, though enough people end up with 12V problems, that a stronger battery might delay that.

Maybe even for me, the bigger size is questionable. A bit of extra weight, and when I need the extra reserve capacity, I'm generally carrying a LiFePO4 "house battery", inverter, and battery charger. Plus always a lithium jumper pack with air compressor built in also, the Uibi X7.

 

Here is something I dont think anyone knows yet... If you install two 85aH AGM batteries, ICE will not turn on as much in a significant way while the vehicle is in Ready mode.

View attachment 264754
https://black.jmyntrn.com/2021/06/06/dual-85ah-batteries-in-my-toyota-prius-with-a-victron-bmv-712/

 

I don't know. 114 pounds for 170Ah of AGM, where you should only use 50% before recharging, so 85Ah usable?

You can now get a 300Ah LiFePO4 battery weighing 56 pounds in Group 31 size, where you can use all 300Ah, for $400. Or 100Ah, 120Ah, and 140Ah ones more comparable in size to the 85Ah AGM. Admittedly, you have to deal with not charging LiFePO4 below 32F. There is no shortage of low-temp protected, and/or self-heated LiFePO4 batteries that run circles around AGM in terms of weight, capacity, and life.

AGM is fine for the main 12V battery needed to run the car. The car is designed for it, and it works under a huge range of conditions.

For anything else, I'm going LiFePO4 and not even considering any lead-based battery. I charge my LiFePO4 via Kisae DMT-1230 DC-DC charger, which also has a solar MPPT charger it switches to when the car is off, if you want to add solar.... which I don't. When camping, I run the climate control while I sleep, so all batteries get topped up while I sleep. The opposite of solar, which tops stuff up during the day, which I have no need for.

 

yeah so... I installed them years ago before the price and options for LiFePO4 came to what they are now. The thing is, I have a PHEV, so I only have the space where the 12v comes from factory and the opposite size to work with. I had to hammer out the space where OE 12V is to fit what I did in there.

Ill be hoping back to my Gen 3 next year, trying to finish this Gen 2 and I'm going to for now use one rack of my PiP HV battery plus 2 additional cells to make a 12v for this Gen 2. I would love to have a 300ah secondary that runs the inverter and rest of the addon electronics like the fridge then a 150ah for the main 12v. These days tho, I've now seen the light into upgrading the hv battery then using it through an inverter... or in the case of a PIP... upgrading both hv and 12v then being able to run my entire setup for 24+ hours without ICE turning on once. Solar hasn't gotten small and powerful enough for me yet so I'm going with attempting a ~50kWh high voltage battery in my 2013 PIP then running two 2000W inverteres off each 12v like I am now. LEaving car in Ready and barely burning any fuel in the process.