Rainbow Prius Hybrid Powered by Lithium!

Are those imax b6 models?

 

Yes sir... The V2 80w ones with updated processor are near twice as fast as the old ones. Also makes me realize how sketchy Version one is in terms of overheating risks because they suck at measuring compared to the news ones.

 

So as mentioned the internal resistance is much lower with lithium (as expected). However, one of the cases that makes these direct conversions problematic is that the inverter doesn't current limit until about 120A+ unless it is compensating for voltage or temperature, it usually uses voltage and internal resistance. This means the currents through the pack will be much higher on average, both in and out. This is good for performance but are the thermal considerations taken into effect? Or is there some custom ECU work to be done?

I do believe a lithium conversion can be done with all the same hardware in the car, but will require a new ECU or at least a FW update to the ECU. Without changing the software control... yikes.

 

It's my understanding this is done by way of the actual chemistry mix of the lithium itself... As for thermal considerations, I'm grateful we're heading into winter and if any problems arise I do have a spare inverter on my parts rack right now. ;-)

 

Rav4 hybrid is now being shipped with either NIMH or lithium. The U.S. started getting Lithium a few months ago while Canada still gets NIMH (for better cold starting?). It would be interesting to find out if the ECU part numbers are different.

I wish I could see into the future to see how the Li batteries are holding up in 10 to 15 years. Any predictions?

 

I was also wondering about the differences in chemistry of the cells and the electronics of the Prius designed for NiMh chemistry. If this works out, it will be a really good replacement strategy.

 

I've not asked Jack yet, but my sense of it is that these are the final pre-production packs and the actual product won't be 3D printed filament and the extra holes won't be there either. This is due to how long it takes to produce one 3D module and in general the strength of 3D printed boxes are not as good as the machine they'll build to make exact same size module containers...

Screwing 3d printed modules on the chassis is an uneasy feeling due to the lack of strength of thin layers of 3D filmanet. But that's just my sense of it, Jack will have to explain further.

 

I've printed a few of the module cases myself, there is absolutely no lack of strength to be concerned about. The walls of the cases are thick and quite rigid, but I believe you are correct that the final product will not be 3d printed.

I should have my pack installed later this weekend or early next week, so I'll let everyone know how it goes. I'll be focusing my testing more on the performance aspects than MPG, given my use case.

 

I’ve got about 100k miles on my ‘08 Prius. I’m going to check out my hybrid battery with the Dr. Prius app.

No codes yet... so I’m hoping you’ll have a lithium battery available before I need to replace mine.

Looking forward to seeing more about your progress.

 

Most of this IR is most probably in the fuse in the service plug (not in the cable).

 

I guess we got the NiMH with 2020 RAV4H.
We have had very few if any 2012 PiP batt fails with the Li. And as long as replacement is rare you can get junk yard batteries cheaply.

Way back before Dorman bought out Re-Involt, Taylor Automotive was working on Prius Li replacements. Never happened.

 

There are a lot of differences in lithium chemistry s. One nice thing about LiFePO4 is it doesn't need as stringent temp monitoring as Li-ion. So the bms can be much simpler. Think Leaf.

 

My pack is installed! I posted in the gen3 thread but I'll copy that post here as well.

I installed Dr. Prius' lithium battery conversion! Everything works, I've linked a video of me turning it on for the first time below. This pack is LIGHT. I needed help to get the old pack out, and MAN are they heavy! The new pack with the lithium modules installed is incredibly light in comparison, and was quite easy to get in the car and set in place.

I just took it for a short drive to Sonic, and was able to get THREE miles of all EV driving, with 40% charge remaining. I hit the gas three times in that span to get going from a stop light so I didn't hold anyone up behind me, but also came to a stop two other times. Previously, I was unable to get a full mile in EV unless I was on the highway. I will take some videos and upload some hard data in the coming days. I also gunned it a few times and noticed an increase in acceleration, both from a stop and in normal driving. Again, more information to come.

I managed to get 54 mpg on my round trip, even with some leadfoot driving. Previously, I'd have been around 38-42.

 

Impressive! Is that a Gen 3?

 

Yep! This is on my 2010 Gen 3. I haven't had much time to test it today, but my first impressions are very positive. 3 miles of EV range with charge to spare is fantastic in my book.

 

Are you sure some USA RAV4 hybrid are getting Li vs NiMH?
Obviously the RAV4 Prime plug-in would be Li.
I got someone on Reddit disputing me on the Li for hybrid RAV4 info