Aftermarket HV battery pack -- a cautionary tale

I'm a brand new member, and perhaps this has been covered before, but I recently learned a lesson regarding after market replacement HV battery packs.

I own a gen 1 Prius, and have successfully replaced the HV battery for a second time, and the car running like new!

The first after market battery, purchased through NAPA, lasted over four years, which isn't great, but not that bad either. It worked out to $35 per month, which is still far lower than a car payment. The battery had refurbished gen 2 cells, and I was thinking if I had only spent more money up front and paid Toyota I would have been running new cells that would last as long as the original battery, well over ten years. For this reason, I tried getting a replacement battery pack from a Toyota dealership parts department, but here's the catch:

Toyota will not accept an after market HV battery as a core return. I'm sure many on this forum already know this, and I simply had not done my homework, but the bottom line is, once an after market battery is purchased, there's no going back.

 

Toyota core charge was $1,350. The OEM HV Battery, P/N G951047020, was the battery assembly without control unit, vent hoses and other parts. A junk battery might work, but would also still need to have a set of good parts to swap over before installing the new battery.

The good thing about the after market pack, is it came fully assembled. The only parts I needed to swap was the safety plug and white plastic vent hose that clips on the end. I'm hoping to get at least four more years out of this one -- fingers crossed.

 

Of course the core would go back to Toyota without any parts that needed to move over to the new battery. The big unknown is the battery ECU, which either from a salvaged battery or the after market battery may or may not work with the new battery. I believe this is why Toyota recommends having a certified hybrid tech do the replacement.

I ended up purchasing a second after market battery from NAPA. It came with the ECU and all the other internal parts, so all I needed to do was bolt in the battery and hook up the wires. It a good choice for do it yourselfers, but the trade off is having reconditioned cells with an unknown life span.

 

PS, NAPA did accept my old after market battery as a core return.

 

The saga continues. The dreaded P3006 engine code popped up just a couple days past the one year purchase date of the replacement after market battery. I thought it was out of warrantee, but instead of saying, so sad too bad, the friendly folks at NAPA contacted Dorman, who built the battery, to see what can be done.

The Dorman battery warranty is based on the 'Install By' Date stamped on the battery, and not the purchase date.

For this reason I was able to get a warrantee replacement through NAPA at no charge. This new replacement battery appears to be much stronger than the last one, and hopefully will work for many years to come -- fingers crossed!

 

Good to know. I called around and was told no after market cores. It also might be different when Toyota is installing the battery. I was trying to buy one and install it myself.

 

Hasn't been a year and just started getting the dreaded P3006 code on the Dorman warrantee replacement battery.

Not sure if the replacement battery came with a new 1 year warrantee, or if the warrantee is only for the original after market pack.

Not sure if I want to replace it myself again if the remanufactured batteries only last a year

I am sure I don't want to play wack-a-mole and try replacing individual cells.

I would like to keep the car going just the same.

 

Quick update. I found a junk core battery to exchange for a new Toyota battery from a nearby Toyota dealership. I installed it myself today, and the car started and ran like new!

As expected the Dorman battery warrantee was only good from the original purchase date, and not the date I installed the warranty replacement, so no luck getting another replacement through NAPA. If the original Dorman battery came with a two year warrantee, I could have gotten it replaced again.

I did swap the battery ECU from the Dorman battery, because one of the connectors on the junk battery ECU had glue or something in it which didn't let me plug in the cable all the way. Probably for the best, since there's no telling how long the junk battery has been sitting around and how much corrosion was inside. I also replace the relay module with a good one from eBay.

(Note new Toyota batteries do not come with ECI and relay modules, these need to be swapped from the original battery.)

 

First Repair replaced cells myself April 2013

2, 7.2V Cells. $70
S/H $13
Bat. replace manual. $15
---
Total $98

Second Repair replaced cells myself May 2013

1, 7.2V Cell $35
S/H $ 8
---
Total $42

First Replacement After Market HV Battery Pack installed myself (Gen 2 Cells) April 2015

NAPA Dorman Battery $1765

Battery Repair replaced cells myself June 2019

3, 7.2V Cells $54

Hybrid Battery Service and Repair Shop July 2019

CC Motors $912
(tested replaced faulty cells, reconditioned battery -- didn't work, cleaned throttle body)

Second Replacement After Market HV Battery Pack (Gen 2 Cells) Aug. 2019

NAPA Dorman Battery $1765
(matched price of first battery)

Warranty Replacement After Market HV Battery Pack Aug. 2020

NAPA Dorman Battery $0

New Toyota OEM Gen 1 HV Battery Pack Installed myself July 2021

Toyota Dealer Parts $1995
junk battery core. $500
main relay. $43
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Total $2538

Original Battery lasted 14 years, which I repaired myself twice costing $140.

First Dorman Battery lasted over 4 years, costing $1765 plus $966 attempted repairs for a total cost of $2731

Second Dorman Battery lasted two years (including warranty replacement) costing $1765

Bottom Line, I payed $4636 for the first 20 years, (which is more than if I took the car in to have the battery placed by a dealer in the first place), and have now invested another $2538 to keep the car going. Will try to recoup a bit of money by selling the after market battery I could not exchange as a core.

 

Last month I tested modules in the Dorman battery I pulled and replaced with the new Toyota battery. None of the serial numbers were even close to being sequential, these remanufactured packs must depend on whatever process is used to test and match modules. Besides this it was clean with no signs of corrosion. There was one low voltage module indicating a shorted cell, which I replaced, so perhaps the pack will now go a few more yeas.

If anyone is interested I'm selling it on eBay: http://ebay.us/9831si?cmpnId=5338273189