We need to get beyond batteries and go to fuel cells and super capacitors for a variety of reasons, but the biggest reason is that frankly, batteries suck. They take time to recharge (typically overnight for the volume of energy we’re talking about for electric vehicles); they are heavy; and they’re expensive.

If you start at the bottom of the rung in terms of effectiveness, lead-acid batteries, the type you find in every car in the US to turn the starter that starts the engine, you’ll find that the battery really hasn’t improved much since the 1890′s. The packaging has, but the basics and performance have not. The proof? The electric vehicles produced in the 1890s as electric taxicabs in Manhattan have roughly the same range that enthusiasts get today when they convert gas automobiles to electric automobiles using the same lead-acid battery technology: roughly 25 miles. That’s 110 years of no progress with that battery chemistry.

Even Thomas Edison knew how badly lead-acid batteries sucked, which is why he was working on a nickle-metal battery for an electric vehicle when his labs were destroyed by fire in 1914, taking his plans up in smoke.

Back to today. To bracket the discussion with the high end, lithium ion batteries that power our cell phones and notebook computers are being used by companies like Tesla motors to power their electric vehicles. But, LiONs use a rare metal that some experts say don’t have enough supply to power the number of electric vehicles that need to be put on the road if we’re going to make a dent in energy independence and global warming. Also, LiON batteries are expensive. To compare the lowest energy density battery with the highest energy density battery:

Lead acid batteries cost roughly $7.50 per amp hour
LiON costs roughly $17.60 per amp hour

And now, even GM in their own way admits that batteries suck. According to GM’s Facts and Fiction “blog”, or, more correctly, PR campaign:

“The EV-1 program ended due to the lack of suitable batteries. “

Which is one very interesting data point on the suckage of batteries. I see two possibilities here. 1) either the statement is true, or 2) if the statement is not true, then at least the GM PR machine knows enough about the suckage of batteries that they can lay the blame for the demise of the EV1 at the feet of batteries and have credible deniability. Either way, it doesn’t bode well for batteries.

Another interesting data point is the fact there there are no utility size battery storage mechanisms. Unlike other utilities like water, which get stored in tanks for on demand use, there are no electricity “tanks” (ie, batteries) at a utility level. All the electrons we use when we plug into the grid are being set in motion at the electrical generations stations; they’re not coming from storage. It’s fascinating to me that utilities are looking at Plug-in Hybrid Electrics as a battery storage mechanism, when they don’t currently have a viable storage option today.

In a nutshell, here are quick pros and cons of types of battery chemistries:

Lead-acid pro: cheap, fairly robust
Lead-acid con: heavy, small capacity per weight ratio

NiCAD pro: ability to handle high currents, lighter than lead acid, can handle high charge rates for quicker charging.
NiCAD con: memory effect (you need to completely discharge the batteries before recharging, which is totally doable with a smart charger), uses toxic cadmium

NiMH pro: lighter than NiCADS, uses more plentiful metals
NiMH cons: can’t charge as quickly as NiCADs, can’t handle high discharge rates as well as NiCADs, more adversely affected by heat (doesn’t seem to a problem in EV’s in the bay area, but I live in Texas and the NiMH AA rechargeable cells I leave out on my back porch in the summer get clobbered by the heat and only recharge up to half their rated capacity), Chevron/Cobasys is suing Toyota and Panasonic to prevent them from supplying EV quality batteries.

LiON pros: lighter than NiMHs, more energy dense, quicker charging
LiON cons: lithium is a rare metal, LiON’s are even more sensitive to high current drain than NiMHs (I imagine much of the engineering around LiON packs for EV’s is dealing with this limitation), high price, need for on board electronics to control charging and discharging.

What’s to be done?

More research into hydrogen development and storage to get us better fuel cells.
More research into super conductors.
More research into better battery chemistries.
Tax incentives for these companies in order to jump start the market.

Clearly, successful electric vehicles will be a combination of batteries, fuel cells, and super capacitors because they all have pros and cons, but the total system makes sense. However, it’s interesting to me that battery enthusiasts bang on hydrogen, but never discuss the energy loss in charging up batteries.

Don’t take my rant against batteries as a rant against a electric vehicles. I think it’s time we take a cold, hard look at how much batteries really do suck, not so that we kill the idea of the electric vehicle, but so that we can shore up its weaknesses and move forward with it sooner.