Ulrich Eichhorn, who oversees engineering for Bentley, says that for the first time in his career there and with parent Volkswagen, he's encouraged that auto industry engineers will finally get the remaining bugs out of lithium-ion (Li-Ion) batteries similar to those used in laptop computers.
That's good news for the auto industry, which is counting on improved Li-Ion batteries as a key component of electric cars and so-called "plug-in" hybrids. Today's hybrids like the Toyota Prius use a conventional gasoline engine to recharge the nickel-metal hydride batteries they use for propulsion when the car is in electric-only mode, which is starting up, and at low speeds and low acceleration. A plug-in hybrid with lithium ion batteries, like the upcoming 2011-model Chevrolet Volt, can be plugged in to recharge at home. That increases the car's range, but first there are some hurdles that need to be jumped.
I spoke with Eichhorn at a press introduction in Boston. Following are edited excerpts of our discussion:
BNET: The main problem with lithium ion batteries is heat, right?Ulrich Eichhorn: Yes. They get quite hot, which anybody who has held a laptop on their lap for a long time on an airplane knows, in the over-air-conditioned interior of the plane you are quite warm. The other problem is they can get a short which can lead to a chain reaction, and they go, "Pfft."
BNET: What does "Pfft" mean? They catch on fire, right? UE: Exactly, like the scary pictures you have seen of laptops that caught fire. It's related to the process that produces heat in normal operation, there is also something else going on that creates waste heat. If there is a problem, more and more of the energy gets devoted to creating this waste heat. That can affect the adjoining cell and you can have a chain reaction.
BNET: So what's changed? Is anybody trying to change the basic physics of how the batteries work, so that they don't produce as much heat in normal operation, or is that something that's inevitable, and they're fixing the chain-reaction problem? UE: It's both. It's like a lot of things in the auto industry, if you are producing heat, it's because your device isn't very efficient. That's why there are gearbox lubricant cooling systems, it's because the gearboxes are not as efficient as they should be. Same here, if your system is producing heat that you don't want, it's because it's not very efficient, and they're working on that.
As for the catastrophic heat, there's a guy who has shot a video where he drives a nail through a lithium ion battery, which would normally give it a lot of problems, and it doesn't go, "Pfft." Does that mean it's solved? I don't know.
BNET: So again, what's changed? UE: The biggest thing that has changed is that there is now a critical mass of engineers working on this thing, with economic viability in mind, it's not just somebody in a lab somewhere who wants to win an award for being Researcher of the Year. For the first time since I am following this, say 20 to 25 years, it's encouraging. They haven't encountered some law of nature that makes this all impossible, which is something I was always very skeptical about.