Fast charging EV batteries and the future of the fuel station

We're heading down a road where large numbers of cars will be powered by batteries in the future. Aside from the cost of batteries (dropping fast), the main reason for consumers to hesitate about jumping into an electric vehicle (EV) in the next few years, is range anxiety. We are not suddenly going to develop cars with batteries in them which will cover 500 miles on a charge, so how are we going to cover longer distance journeys?

The auto industry is (sensibly) proposing a solution which meets the average driver's needs about 95% of the time. You'll be able to drop the kids at school, get to work, and then home again via the shops all on one overnight charge, which you'll do either at or outside your home. But for road trips and non-average commuters, a host of new partner firms (and industries) claim to have a solution to the range problem. Best know of these is BetterPlace - who are developing an electric car charging network in several countries, and who will provide roadside swap stations in Israel and Japan within a couple of years, where you drive in and a depleted battery will be swapped - within two minutes - for a fully charged one.

But there's another solution which falls between the standard eight hour overnight charge, and the battery swap solution. It's known as the "fast charge" and it's a term which is being bandied about with increasing frippery. We've seen a section of the emerging EV industry (both start ups and established auto OEMs) change their tune about this. Back in 2007, no one had an answer to the problem of how to juice up the car's battery quickly if you ran out while on the go. Yet just two years later, here's the stock answer:

'With our fast-charging technology, running out of juice won't be an issue - as on a 440volt charge outlet, we can 80% recharge the car's battery in 20-30 minutes.'

So what's changed? Nothing really - the battery chemistry has improved a little in the last couple of years, but not by that much. So at the recent Frankfurt auto show we tried to get to the bottom of why, suddenly, fast charge points are technically possible, and asked several people what their view on this was. Here's the MD of Ford's Advanced Research Centre in Europe, Andreas Schamel who's far from convinced (skip to 1.04 for the skinny):

His view correlates with what Toyota's Bill Reinert has been saying for years. Quite simply, to put that much juice into a battery, that quickly, is problematic from a power-grid point of view. And BetterPlace's tech guys back the view that it could be troublesome as a solution. As one of them remarked "it's like taking a firehose to the battery". So, even if you can tap that amount of power to plug into the car, actually charging the battery so quickly creates serious problems, potentially prematurely shortening its life, and more pressingly, generating large amounts of heat. Lithium-ions don't like getting too hot, and in extreme cases where they do, thermal runaway can occur, causing fires of the type reported in laptops over recent years.

Hyundai's Tom Barnard looks at it a little less pessimistically. He acknowledges that there might be some implication in doing fast charges, but says that lithium-polymer battery technology copes better from the heat perspective, and suggests fast charging should be seen as a 'last resort' charging solution, but one which helps overcome the fear of getting stranded. He's not suggesting it's something we will be doing every other charge though. 

So let's assume for a minute that a battery that's happy to be fast-charged now and again exists. How's the electricity going to be provided? This is where we get to the idea of the future fuel (or gas) station. Several people we've talked to have mentioned the notion of ultra-capacitors as giant 'power sinks' or buffers to overcome the issue Schamel and Reinert talk about. Drip feed electricity from the grid into a massive one of these over the course of a few hours (and when grid load is light), and they can store loads of power - enough to provide several 'quick blasts' to charge up several cars quite quickly.  The EV Does It blog has a neat explanation of how this might work.

It means that the filling station, as we know it, could gain a new lease of life. Because not only is this 'premium', fast service something that you could charge for, far over and above the price of electricity, but it allows for the reinvention of the typical service station's look and function. Principally that's because while your car is charging up for twenty minutes, you're going to want somewhere to have a coffee, sit down, perhaps even do some work.

Am I alone in thinking that this would not only be appealing to the business world (they get a captive audience to sell stuff to)? But also to the design world, who'd get the chance to reinvent a whole building typology, which - with a few notable exceptions - has for the life of the gasoline car, remained something of a design backwater? Send your ideas for the future of the 'fuel' station on a postcard to the usual address...

Posted by Joseph Simpson on 09th October 2009

Images credit: Gas Station - raindog, Electric recharge/Shell station - Todd Mecklem, both on flickr

Disclosure: Ford is sponsoring our research through 2009

Comments

[Todd Mecklem]

Interesting post. Thanks for the photo credit--my last name is misspelled, though--it's Mecklem.

[Charmermrk]

Hi Todd, thanks for this and for the use of your picture. My apologies for the mis-spelling of your name. Joe

[evnut]

The other possibility is redox technology. Look at the latest press releases from Fraunhofer. I have been thinking for years about redox replacing the typical gasoline fueling station, but the problem has always been energy density in redox batteries. It looks like this might have been solved. Here is a link:
http://www.carformance.com/electric-power-from-redox-battery-equals-lithium-ion-10161927/