Porsche goes into Lithium for Porsche prices !

[MrKang]

Came across this article :

Perhaps only Porsche, with its long legacy of pricey options, could consider charging $1,700 for a starter battery.

To be fair, this isn't just any old 12-Volt lead-acid starter battery. It's a lightweight, lithium-ion pack with a similar form factor and the same mounts as a standard battery. It's not only 3 inches lower, but also--at 13 pounds--a full 22 pounds lighter than the original.

The lithium-ion starter battery will go on sale in January as optional equipment in the 2010 Porsche 911 GT3 and GT3 RS, along with the 2011 Porsche Boxster Spyder that launched last week at the Los Angeles Auto Show.

Lithium-ion batteries are more often associated with electric cars--think 2010 Tesla Roadster Sport--and the newest generation of hybrids, including such sedans as the 2010 Mercedes-Benz S400 Hybrid and the 2010 BMW ActiveHybrid 7.

Their greater energy density makes them smaller and lighter than either lead-acid or nickel-metal-hydride (used in most hybrids today) for the same weight.
Versus a traditional lead-acid battery, the lithium-ion pack recharges quicker and is longer-lived. That's because it can endure far more charge-discharge cycles without degrading.

Its one weak point is low-temperature performance. Porsche actually provides a lead-acid battery to go along with the lithium option, since the old style works better once temperatures fall below freezing.

But the Porsche battery does only what starter batteries traditionally do: turn the starter motor. The car's wheels are still turned solely by the characteristic flat-six engines. And the lithium-ion battery has nothing to do with that all-electric 911 concept, either.

 

[julesa]

Pricing aside, 13 pounds is a lot of weight for 235wh. LiFePO4 typically gives 100-110 wh/kg so that should be about 5 pounds. Maybe the terminals and connections are all solid gold.

 

[redorblack]

26C?

A bunch of electronics in the base to protect it during charge and discharge?

Who's cells are they using? Look like the Headways in there but it says lithium ion, not lifepo4.

 

[Lock]

...but it says lithium ion, not lifepo4.

Actually the label in the pic does say (German) "Lithium-(something)-Phosphat"... and also GAIA:
http://www.gaia-akku.com/en.html

Prototype LFP datasheet here:
http://www.gaia-akku.com/fileadmin/user_upload/downloads/cells/38AhHE_LFP_Prototyp.pdf

Tks
llOk

 

[Lock]

Curious to hear what others think about these GAIA 38Ah cells... but also any ideas why GAIA would design these cells with aluminum positive terminals but copper negative terminals?
tks
lokk

 

[BMI]

Curious to hear what others think about these GAIA 38Ah cells... but also any ideas why GAIA would design these cells with aluminum positive terminals but copper negative terminals?
tks
lokk

Many of the cells made with threaded terminals use an aluminim positive terminal and copper negative terminal,
I can only assume you have never seen a PSI or old Lifebatt or BMI 40138 cell before.

 

[liveforphysics]

Curious to hear what others think about these GAIA 38Ah cells... but also any ideas why GAIA would design these cells with aluminum positive terminals but copper negative terminals?
tks
lokk

The cathode (+) is graphite, and aluminum is tougher to connect to carbon than copper.


This is actually very good bang for the buck for weight reduction compared to other parts for pretend sports cars like Porsche. They sell carbon body panels for muli-thousand dollars to replace the aluminum panels at a weight savings often less then 2lbs...

 

[redorblack]

Good catch... I went by the article quote.

In car racing terms a 10 lb weight reduction is considered the equivalent of 1hp increase in power, shaving weight is often more important than adding horsepower. 22lb reduction that 'easy' on a car that expensive is a bargain. Wonder what the life expectancy is in that sort of environment. Average lead acid battery gets about 5 years if the car is regularly driven and under 'normal' conditions.