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

I believe @2k1Toaster said the CEBA battery kit fits into the overrated category according to his tests. CEBA uses the same brackets as the good kit, but much cheaper cells.

 

Would you mind elaborating on "The Honda solution is terrible"? I'm aware of some of the shortcomings of Honda's battery management (and why), but I'd like to hear your take on it.

Anyway, I'm not trying to damage your business, just concerned that these batteries may not be ideal for use in Priuses, for several reasons including but not limited to 1) the Prius prismatic packs show less self discharge than any cylindrical stick we've been able to find, which may contribute to balance problems seen in vehicles which use them, 2) different voltage curves meaning these sticks will be run in different SoC ranges than Prius packs, which will have an unknown effect, and 3) the small degree we've found Prius packs to self-balance, which has been presumed to be why Toyota moved away from cylindrical cells in the first place.

I suppose we won't know how long these packs last until the first of them start to fail though.

 

There are other companies/rebuilders now getting into selling cylindricals. I've been involved with hybrids since 2004. It is interesting to watch how the aftermarket battery space evolves/changes over time.

 

I've now been contacted by half a dozen companies who want to sell me packs with cylindrical cells. Strange.

 

Yeah, several Prii in the family and I'm pretty familiar with the HSD and how they drive. It's definitely a superior system overall to the IMA and I wouldn't recommend a Honda hybrid based on the IMA to a family member who doesn't like to work on cars.

For the sake of accuracy though:
-Honda's IMA hybrids have no more or fewer belts than those based on the 1.5L mill. The newer serial hybrids (Accord hybrid 2013+, Clarity, Fit) are beltless and A/C runs while the engine is off. It has a less complex transmission than the orbital gearbox in a Prius.
-Aside from the first generation Accord hybrid, Honda hasn't sold an automatic hybrid that "shifts" - they're all CVTs or serial hybrids. That I feel those CVTs are lousy is another matter.
-Creep works on Honda hybrid automatics, just like on any other automatic. It doesn't work on the manuals, just like any other manual.

Anyhow I digress. I just wanted to share what I knew and bring a word of caution about using aftermarket cells.

 

OK so my rebuild kit from newpriusbatteries arrived on schedule yesterday.

I replaced my 12V Optima battery which had failed either due to defective or being discharged during the winter. NAPA now has an exact replacement for the original that fits better than the Optima, so I used that. The 2005 Prius runs again, but still has the triangle of death indicating a failing traction battery. I think it will be common that a Prius left standing for a few months because of a bad traction battery may also need a new 12V auxiliary battery.

The 70 pound package came UPS, and it was neatly packed with styrofoam around the modules. Everything looks to be in good condition.

Newpriusbatteries also sent the latest version of the installation manual via email. The procedure they recommend looks simpler than the procedure I used to replace the original battery with a salvage one about five years ago. I removed the rear seats that time, and it took me two days to put the car back together. I won't be able to begin the rebuild until Friday, when I have a day off. In the meantime I will study the installation manual and set up a place to do the work.

 

You still have to remove the seat backs to get to the forward facing bolts on the hv battery brackets. After unbolting them just slide the backs forward and vertically into the corresponding footwell. No need to remove the seat bottom.

Please get an inch-pound torque wrench so that you are confident that each nut on the HV battery is properly torque. Undertightening can create dangerous (fire starting) arcing. Overtightening will strip or damage bolts leaving the module or component unusable.

Additionally, getting a a few diagnostic tools (cost less than $75) will help you read and clear codes, see live data, and more. Will also help if you need to communicate and describe problems to others online or over the phone.

I assume you won't use protective equipment, but that's just the way it goes I suppose. Would be best but most people assume accidents won't happen to them. I understand.

 

I'm considering to purchase a 2005 or 2006 Prius.

Besides the 1 year warranty, should these new battery cells last for as long as the originals, i.e. 10 years or longer?

 

OK so the battery is rebuilt, and everything has been running fine since Sunday.

Nick Vergunst from newpriusbatteries emailed me the latest installation manual as a pdf. I uploaded it to my cell phone so I would have it handy while I was working.

The instructions for removing the upholstery and seatbacks are good, but some of the bolts are in a different place on my 2005 GenII.
Overall this was much easier than the last time I replaced the battery. That time I followed a youtube video that had me removing the seats completely. I found the back seat to be a comfortable place to do the rebuild.

Instructions for installing the new modules begin with a torn down battery. Instructions for tearing down the old battery are missing. Since I was already familiar with the insides of the battery, I knew what to expect. As soon as the battery was unbolted from the floor, I placed two stacked 2x6s behind the battery and carefully lifted it up to expose the bottom screws holding the old cells. Then I removed all 56 screws and set the battery back down before removing the cover.

I know now that after I removed the cover, I should have unbolted the computer. This would have allowed access to the upper tension rods with a normal socket set and saved a trip to the hardware store. I removed all the wiring and cabling from the 28 old modules. I unplugged the voltage sensor cable harness from the computer and replaced it with the new harness that comes in the kit. I removed the upper tension rods completely and loosened the lower ones. Then I pulled the old modules out and placed them in a closet for later sale. The battery was then much lighter and easier to lift.

In the genII you have to clip temperature sensors to the blue plastic holders and snap them on modules 2,7, and 13 when the cells when the modules are first lined up. These are on the bottom of the modules in a genII, and the access is difficult or impossible at the later stage where it is suggested in the manual.

It is possible to do the complete rebuild from the back seat. I did it, but the how is too complicated to explain here.

So far I am completely satisfied with the result. I will post back again in a month.

 

Generally I would reccomend against didmantling a battery in the car. There is a lot exposed metal which make it easy to accidently short out or damage the electric components. If you are forced to work in the car, perhaps putting down a non conductive mat or blanket might be a good idea.

Due to the routing of the front fuse holder cabling, I would suggest periodically removing the cover to check for chafing. Unless you know 100% that you routed the cable in such a way to prevent it. The existing cable is just a tiny bit awkward when fitting it on the cylindrical seup. It is easy to compensate for it. Just a good thing to make note of.

 

I was concerned about whether you would need to raise your price.

 

ME TOO! A fantastic idea, do keep us in touch, it can only get better! TY

 

Anyone know if replacing my cells with the cells from a wrecked 2013 prius with 107k miles would be worthwhile? I'm getting the entire set of 28 from a friend for $600. Or are the gen3 batteries less reliable?

 

That’s about $21 a module, so a great price.

If you swap em all out, you’ll be in good shape for awhile.

Go for it .

 

Assuming the wreck is not a PiP. They use a different battery chemistry.

 

I agree with @Raytheeagle and @Prodigyplace. My wife's 2007 has a full set from a totaled 2015. Works GREAT!!! $600 sounds very fair.

I would suggest that you also get the grid charger from Prolong Grid Charger Product Guides – Hybrid Automotive and balance them all once installed. Since you'd have the battery out anyway, it'll make it even easier to install the charger cable.