battery interchangeable?

@Tideland Prius may want to weigh in on this since he has access to parts lists.

 

I thought your PiP was Gen 3.
Some parts swapping may be needed and it probably is not economical to do so, though.

 

of course i meant the lift back. didn't you post the company that was trying to develop a li-on battery for prius replacement?

 

no idea.

 

no, but somebody posted a thread about a company that's been trying to do it for years. and there is another thread from a guy who claims he's going to do it himself, so, 'stay tuned'.
i'm sure it can be done, but most people are not competent enough to do it, and i doubt it is a 'drop in' replacement, but i can't prove a negative.

 

Third gen PIP is lith ion??

 

Engineers don't think like you do. In order to determine what an engineer will do, you have to be privy to what he/she is told their scope of work is. I doubt the scope includes packaging around battery chemistry and ease of replacement.

 

If you meant me, I only recall about Todd putting Gen 2 Ni-MH modules in a Gen 2 pack and that the PiP has Li-Ion.

 

I think it's formally called a 1st Gen PiP, but it's based on the Gen 3 hatchback design. And, yes, it is Lithium Ion. I keep hoping @jeff652 will release a grid charger for it.

 

The real question is, "Can you prove that you can't prove a negative?"

 

He probably needs a "guinea pig" for testing Gen 4 Ni-MH. mine is probably too new with about 12K miles.

 

I am an engineer/inventor (now playing a university professor). I seldom limited my designs by the constraints given to me by the boss (or marketing) as I knew that the constraints would change as the project proceeded. I can give you a famous example from computer history that makes this point.

An entrepreneur asked Intel to develop a custom chip for an early scientific calculator. The engineer assigned the task didn't trust the stability of the chip specifications so he came up with a generic chip that could be specialized to do the required functionality by storing some instructions in read only memory. The project was canceled by the entrepreneur, but the chip was then successfully marketed as the 4004 - the first microcomputer.

JeffD

 

I am also an engineer (computers) and I agree with @jdenenberg with a small exception: I TRY to generalize my designs to the greatest extent I can for exactly the reason he states. But, cost targets usually dictate design constraints much more rigidly than design specifications.

 

There are differences between the fourth-generation Prius models with NiMH and Li-Ion batteries (model codes ZVW50 and ZVW51, respectively) that likely make it impracticable to use an HV battery of one type in a vehicle built for the other, at least without replacing quite a few other components. Even then, as others have noted, there could be safety or reliability implications that might not be obvious without access to Toyota’s proprietary design information, and for this reason, I’d advise against any such exchange.

Some of the differences between the models are revealed in the Repair Manual and Electrical Wiring Diagram, both available by subscription to techinfo.toyota.com. These documents have two versions of the text and diagrams for the hybrid system, one for NiMH and one for Li-Ion.

The HV control ECUs and engine control modules for the ZVW50 and ZVW51 models (in the U.S., One/Two and Two Eco/Three/Three Touring/Four/Four Touring, respectively) have different service part numbers, indicating at least differences in software; I don’t know if the hardware is also different. There are different blowers and junction block assemblies for the two battery types, though the transaxle and inverter are the same.

ZVW51 models have a battery ECU assembly, connected to the HV control ECU over a CAN bus. ZVW50 models don’t have a battery ECU; instead, they have a battery voltage sensor, connected to the HV control ECU over dedicated serial lines. This difference in architecture also affects the wiring harnesses, of course.

Everyone has access to the Electronic Parts Catalog now; it’s on parts.toyota.com.

 

I thought you were one! Sorry for that!

 

@Elektroingenieur has access to the Toyota documentation. @ericbecky is one of our hybrid experts. I know @TampaPrius.com (Todd at Tampa Hybrids) has worked on battery module swaps.

 

OK. Jumping in here. I think I have the gist.
Basically can the cars with NiMh be retrofitted with the lithium in the future.

I doubt it. But I've certainly been wrong before. Charging curves, discharging curves, capacity, internal resistance, are very different between lithium and NiMh.
Physical differences, programming differences.

Interesting idea to go from one to another, though.