Nickel-Hydrogen Batteries for Hydrogen Cars?

Now days most models of hydrogen fuel cell cars come with some sort of hybrid or plug-in hybrid batteries to increase mileage and range of the vehicle. The major automakers have come to realizing that the marrying of these two technologies (fuel cells and batteries) will be a winning combination for years to come.

Battery electric vehicles (BEV) require a vast recharging infrastructure to be built plus beefing up the electric grid to support millions of BEV’s will be no easy task. Likewise, fuel cell only cars will require a vast hydrogen fueling infrastructure to be built to support millions of cars.

But, what if we could split the energy needs between hydrogen used as fuel and electricity stored in batteries? This would require that two different sets of infrastructures be built (hydrogen refueling and electrical charging stations) but these two infrastructures together would be much smaller than the current gasoline infrastructure plus this would not put as big of a strain on the electrical grid as BEV’s alone would.

Right now the batteries of choice for hybrid cars are either lead-acid or lithium ion with some form of lithium ion seen as the future of hybrids, plug-in hybrids and BEV’s. But, what if nickel-hydrogen (NiH2) batteries were to take over the market instead? What if future hydrogen fuel cell cars were also powered by nickel-hydrogen batteries as well?

What brought this to mind was an article I read yesterday about how Panasonic has decided to reduce its stake in a joint venture with Toyota in developing batteries for hybrid cars. The battery of choice is not lithium ion but rather nickel-hydrogen.

Now, NASA has been using hydrogen as a propellant for years for their spacecraft. NASA has also used hydrogen fuel cells to power onboard systems and supply drinking water for the astronauts. But, NASA has also been at the forefront of developing nickel-hydrogen batteries for use in spacecraft especially satellites.

According to the Florida State University website, “The nickel-hydrogen battery has a nickel oxide positive electrode similar to the nickel-cadmium cell, and is like the hydrogen-oxygen fuel cell since it has a hydrogen negative electrode. This hybrid battery has a long cycle life, high specific energy, high power density, and also exhibits tolerance for overcharge, and is therefore the choice battery in many aerospace applications, especially geo-synchronous (GEO) and low earth-orbit (LEO) satellites. In addition, the battery’s hydrogen pressure is a good indicator of the charge state of the battery.” The nickel-hydrogen battery from the FSU website is pictured above.

Now, yes there are some hydrogen car purists who would not like to see batteries of any kind used on H2 cars for supplemental energy. At the other extreme are BEV enthusiasts who thumb their noses at plug-in hybrids and anything that is not lithium ion. But, meeting in the middle are those who see the value of hydrogen plug-in hybrid vehicles as the integration of the best of technologies we have today and most probably for decades to come.

For more reading about nickel-hydrogen batteries see:

http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel3/62/3208/00103781.pdf?arnumber=103781

http://adsabs.harvard.edu/abs/1993STIN…9413265D

http://www.electrochem.org/dl/ma/206/pdfs/1465.pdf