I've been following the Tesla story for some time now and I think they are set to be the real game changers in the auto industry - mostly because they
are NOT connected with Big Oil or the Internal Combustion Engine industry. Nearly all other electric car manufacturers already make ICE cars and their
offerings so far are nothing much more than "compliance cars" - made to comply with one or other of the State requirements to reduce average overall
Yes, there WAS a battery technology capable of outperforming all but the new Telsas and it was developed by Stanford Ovshinsky some 20 years ago.
Chevron no longer own it (look in Wikipedia for the latest updates on "Patent Encumbrance of Large NiMH Automotive Batteries") but they sure do
Here's the deal: according to Stan Ovshinsky (check youtube for his interviews) the original battery he developed for GM's EV1 took the car 201 miles!
GM said "too much" and limited the capabilities!
Now, I know that most people say that NiMH is old tech, but NiMH and Lithium battery development started at almost exactly the same time. Chevron did
a very good review of battery tech (now why would Big Oil be concerned about electric cars?!) and concluded that NiMH was the best bet as regards ease
of use, safety, and cost.
Then they buried it!
So the world forgot about NiMH - except for the billions of rechargeable AA and AAA cells sold every year.
In the intervening years since Stan's first generation batteries we've come a long way --- NOT.
The First Generation Toyota RAV4-EV used Panasonic's EV-95 battery pack (an improvement to Stan's original battery) that was specifically designed for
electric vehicles. Panasonic developed the engine management unit and battery control unit and sold the whole deal as a package to anyone who wanted
to build an electric car.
About 700 of the original RAV4-EVs escaped the crusher when the Auto companies successfully overturned California's Zero Emission Directive, and most
of these cars are still being driven today with very little servicing, more than ten years later! Some of them have driven more than 150,000 miles.
That's some Road Test!
The crazy thing is that the original RAV4-EVs with their first generation NiMH batteries actually outperforn Toyota's new RAV4-EV - and that one uses
Tesla's drive train!
Bottom line: we need a cheap, reliable electric family car (not a golf cart or 2-seater please!). Lithium batteries are getting cheaper but they are
still pretty pricey for any decent range. NiMH could be a very good answer because the tech is mature (but stagnant for the last ten years thanks to
Chevron), the batteries are ultra-reliable, MUCH easier to control than Lithium technology, work over a wider temperature range (Panasonic claimed
-30C to +70C) and withstand full charge to deep discharge better than Lithium as well.
As far as I know they are also very much safer and far less fire risk - Dreamliner anyone?!
Panasonic got scared off when COBASYS (the battery division of Chevron) sued them for $30 million for making the EV-95s, and even the Panasonic
department dedicated to NiMH development is now majority owned by Toyota. Crazy or what?
Yes, Lithium batteries are lighter than NiMH for a given power but not necessarily smaller! And in an electric car the weight is less important than
in an ICE car. Mostly it affects the accelleration (more mass to move). But a heavier car also regenerates more charge to the battery when it slows
down so the weight is partially offset by this.
Another factor? Lithium batteries are unhappy if they are continuously cycled less than 30% State of Charge or more than 80% SoC. It shortens their
life expectancy. Tesla recommends charging to 77% on the Model S unless you really need the full range. NiMH can run 10% to 90% minimum all the time
meaning more available power from a given kWh battery size (this is from Panasonic's data sheet for the EV-95 from 1998). Suddenly the advantages of
Lithium are not so great.
Any thoughts out there about this? I want to see Tesla succeed in the electric car market but I also want to see cheaper reliable tech for the masses.
Could we have NiMH for the basic family car (look how much NiMH AA batteries have improved and got relatively cheaper in the last 15 - 20 years - we
could have had that with the bigger car batteries as well) and Lithium for those who want ultimate performance (at a price!). How much control does
Chevron still have?
Lots of things to think about ....
edit on 24/1/13 by JohnBingham because: spelling correction