Prius Battery Replacement (GenII) Like you've never seen - NEW Cylindrical Cells

As promised, here’s some data :

2010 Prius II with 175 k miles and had hybrid automotive Prolong equipment battery maintenance:



2010 Prius III with about 73 k miles:


2014 Prius v with 47 k miles:


All relatively consistent .

Hope that helps .

 

I'm in. Just pre-ordered 2k1toaster's kit for May. My 2005 died few months ago. Last time the traction battery died was five years ago, and I bought a salvage battery and put it in myself. These days I wouldn't trust salvage; all of the gen IIs are getting old. I don't think this is for everyone, but I am a retired electrical engineer myself, and an avid DIYer. I resurrected my 1999 pickup, so I am not stranded and not in a hurry, but I am paying $300-$400 a month in fuel for that beast.

Will keep you guys posted on how it goes.

 

how have these aftermarket batteries held up? I think my battery is on the way out so i'm looking into replacements. I also have a Prolong Battery Charger / discharger, and i'm assuming It's still compatible? Thanks guys.

 

too soon to know, but see post #361. check with prolong about compatibility.

 

Based on that post, it is my opinion that somebody would need to try the Prolong charger on a pack, very carefully monitoring the cell temperature. Of the people here, I think only @jeff652 and @2k1Toaster likely have the needed temperature monitoring equipment. Perhaps the pack need a slower charge and/or discharge rate to keep the temperature away from the critical zone.

 

My apologies if this has been covered in the thread before, but I found this while doing research on prismatic conversions for Honda hybrids. My understanding is that one of the major advantages of Toyota's prismatic cells is that they self-balance more readily within each module. To my knowledge, all Honda NiMH hybrids and the early Prius with cylindrical cells had issues with the cells getting out of balance, for which the only solution was to manually balance them with a grid charger, which is inherent to the cylindrical cell design. You need cell-level balancing to combat this. You're fine for a few years, but eventually the out of balance cells cause problems if you don't manually balance them.

Has this been taken into consideration with this swap? Does it even matter, if you can reasonably get 5-8 years out of the pack before imbalance starts to cause major issues?

 

I am sure @2k1Toaster has taken that into consideration since he works with rechargeable batteries daily. He should be along in a while to explain his design & testing.

 

Have you been able to fill all of your backorders yet? This is April.

 

Thanks for the update.

 

Welcome!

I think this is the more important real world issue as folks currently getting these module kits are for 10+ year old cars. I don't think many will want to put more $$$ into battery maintenance when these cars are 15-18 years old. Also, I would think by then new NiMH packs (modules) would be so cheap it won't matter.

 

I break down cordless electronics for scrap. I used to take NiCd and NiMH batteries in to be recycled. Now my recycler tells me they will start charging to take NiCd and NiMH batteries off my hands.

I can't imagine how much cheaper it can get than being forced to pay to get rid of it.

Be prepared for lots of nasty chemicals to be in the waste stream. I think people will throw them in the trash rather than pay to recycle them.

 

UPS confirms my kit has shipped. Supposed to arrive on Monday. Sooner than I expected.

Meantime I need a new 12V battery. My Optima replacement didn't last a year. I bought it online for a good price, maybe too good. My first Optima from a local store outlasted the warranty. Also there was no core charge in the online purchase, so I wonder if there may be counterfeit Optima batteries being sold online.

 

I'm aware, neither does Honda. The running hypothesis as to why cylindrical cells in sticks go out of balance so much more quickly than prismatic cells is that the prismatic cells share airspace between the cells, whereas cylindrical are all independent, and there is some chemistry going on inside them which helps to keep them balanced. Honda packs can get unusably imbalanced in a period as short as 5 years, and it's common practice to bring "dead" Insight and Civic Hybrid batteries "back to life" with a forced overcharge to balance the cells. I understand the battery management is considerably different between Honda and Toyota as well, but these balance issues have been documented and demonstrated by several independent battery providers for Hondas.

Taken (out of context) from a discussion on InsightCentral:

Replacement new cells for our cars have shown a greater tendency to become imbalanced, shorter lifespans with the sort of currents involved. The original cells have been out of production long enough that it's starting to make sense to use aftermarket sticks, but they are noticeably inferior, despite whatever specs are printed on the outside.

 

Back in the day there were cylindrical sticks that had such poor welds that simply waving it around made the sticks break apart.

Or ones that touted higher capacity than what could realistically fit in that size package.

When you unrolled some cylindricals to show the amount of material it was drastically lacking.

I'm sure stuff like that exists out there still, so buyer beware.