Ni-Cad batteries cost

<div class='quotetop'>QUOTE(FishHawk @ May 26 2007, 05:13 AM) [snapback]450335[/snapback]</div>

FALSE. The Toyota Prius II battery stack consists of 38 prismatic NiMH modules connected in series. It delivers a nominal 273.6 Volts and has a 6.5 Ah capacity. No Ni-cads in the Prius. NiMH batteries are less detrimental to the environment than NiCd batteries.

 

<div class='quotetop'>QUOTE(seasalsa @ May 26 2007, 08:35 AM) [snapback]450342[/snapback]</div>

Also False. The classic Prius (2001-2003) battery was a 273.6 volt NiMh, The 2004 and later Prius NiMh battery is rated at just over 200 volts. Just trying for accuracy.

JeffD

 

As Seasalsa said, no Cadmium in our enviormentally correct Prius cars.

And its a good thing too. Ni-Cd's have a nasty habbit of forming internal shorts, and going up in smoke. The first Hybrid Car I ever saw, suffered this fate back in 1978 or so. It was a university research project, and over the summer vacation, it went up in smoke, due to the NiCd batteries.

NiMH batteries do not have this problem, and the lack of Prius fire reports proves this out.

As far as battery costs, the HSD (Hybrid Synergy Drive) system takes advantage of the electrical nature of the transmision to allow it to do the starter and alternator functions in the car. Yep, the transmission is the starter, and the alternator, beside being the transmission. So, the HSD actually costs less than cost of the battery, in comparison to a standard automatic transmission, starter and alternator car.

The battery cost $2400 for the present generation Prius, and is made up of prismatic modules (not D cells) that are 7.2 volts each. The total voltage is 201 volts. The 273 volts is for the first generation Prius, and that battery is more expensive. The cost of the HSD altogether is $2000 per Toyota engineer public comments.

Compared to a standard Camry (the same interior space sized vehicle as a Prius), the Prius has 25 mpg better performance in 50/50 city/highway drivng. So, each 1000 miles the Camry uses 34.5 gallons ( 1000 / 29 mpg) of gas, and the Prius uses 18.5 (1000 / 54 mpg) , for a difference of 16 gallons. At $3/ga average, the Prius pays for its battery and HSD system in 42 K miles. And this does not include the reduced maintanence on braking wear surfaces (electric brakes on Prius slow the car down to 7 mph, and the traditional friction brakes take over from 7 to 0 mph).