generation 3 technology in 2004-2008 Prius

i wonder at times... I would love a battery that charges faster and holds more.. a lot more

 

Current information from Toyota is the 2010 gen 3 model will still use a NiMH battery. The LiIon battery won't be ready for 2-3 years after that, according to Toyota spokespeople.

A LiIon battery uses a different charging system compared to a NiMH battery. If you wanted to eventually "upgrade" (it remains to be seen if this would actually be "better") to a LiIon battery you would have to either change or reprogram (whichever is practical) the inverter and inverter control.

NiMH technology is mature and the batteries are proving to be reliable over long term use. They are very stable.

The benefits of moving to LiIon are lower weight and larger capacity, in a similar volume.
The downsides are lack of experience re reliability and methods of use. There is now also a reluctance in the general public to "trust" LiIon technology, after all the reports of fires in laptop use.

 

Li-ion and Ni-Mh are incompatible batteries. The voltage per cell is different, the charge rates are different, the charge curves are different. Any one placing a lithium ion battery in their Prius had better have their life insurance paid up to date.

The software would have to be changed, the inverter would have to be changed out, a voltage regulator would have to be changed (to charge the battery) and all of this would have to be accomplished within the frame of the car.

This is what the PHV groups have been playing with. Fun stuff for the engineering types.

 

how I wonder are the newer batteries charging faster and holding more charge then? Is the battery pack going to get bigger in the 2010?

 

I think the sensible thing to do is to keep your car for 10 years, for full value and then at that point maybe convert to desirable and doable technology either in the form of a brand new car or a upgraded conversion. I have an 2005, so that means by 2015 I may be able to upgrade my Prius easier and cheaper. Afterall it does everything I want in a car. Even tho I have two Apteras on order, that avenue is also up in the air, at this point in time.:clock:

 

If you're asking about NiMH batteries, the limitation of charge rate is mainly heat. So you use larger plate connectors inside the cells, better routed (shorter and heavier) runs to the outside terminals, and make the cells so they dissipate heat better. It might also be possible to tinker with the cell chemistry a bit to enhance rapid charging.
Then you pack the cells together so you can better extract the heat and vent it outside.
Perhaps you could (if you were a Toyota engineer) change the shape of the pack so you could fit more battery in the same size car (there is a lot of "wasted space" under the current cars cargo box).
Next you improve the charge control electronics, perhaps with temp. sensors on -each cell-, perhaps with better charging technology (pulse with reverse pulses and the like).

If you're asking about the new to come LiIon battery pack, generally a LiIon pack will hold about three times the charge in the same volume, and at lower weight, than a NiMH pack. The charge control and heat handling are two of the main things they are working on to make the pack practical.

Keep in mind, it's the Panasonic division of Matsushita Corp who are doing the batteries. I'm sure the Toyota engineers are working closely with them. I understand Panasonic and Toyota have formed a joint venture battery plant. Probably to guarantee "other business" of the Panasonic division doesn't interfere with battery production. Toyota has cars to deliver!

 

The answer to both your questions is YES.
Most all of us have considered the virtues of a larger or more powerful battery. And infact, there are aftermarket companies already doing Li -Ion conversions. But these are piggy-back battery applications and the additional battery cannot be recharged by the Prius, on the go, like the stock battery, for all the reasons stated above by others.