The future battery
How much has the battery
improved during the last 150 years? Compared to other advancements, the
progress has only been moderate. A battery holds relatively little
power, is bulky, heavy, and has a short life span. Battery power is also
very expensive. The smaller the battery, the higher the cost-per-watt
becomes. Yet humanity depends on the battery as an important portable
power source.
The speed at which
portability and mobility is advancing hinges much on the battery. So
important is this energy source that engineers design handheld devices
around the battery, rather than the other way around. With each
incremental improvement of the battery, the doors swing open for new
products and enhanced applications. It is the virtue of the battery that
provides us with the freedom of being disconnected from home and office.
The better the battery gets, the greater our mobility and freedom will
become.
The improved runtime of new
portable devices is not credited to higher energy-dense batteries alone.
Much improvement has been made in reducing the power consumption of
portable devices. Some of these advancements are, however, counteracted
with the demand for faster processing time of laptop computers and
quicker data transmission of cellular phones.
The electric vehicle failed
because of the battery. Short distances between recharging and a limited
service life of the battery are to blame. Consumers demand a battery
that will last for the life of the vehicle but battery manufactures are
hesitant to provide the mandated 10-year warranty.
Battery research is
proceeding at a frantic pace. The average annual gain in capacity is
typically 6%. In comparison, microelectronics has done much better.
Gordon Moore made his famous observation in 1965 when he predicted that
the growth in the number of transistors per integrated circuit would
double every two years. Through Intel's relentless technological
advances, Moore's Law has been maintained and is being carried into the
21st century. Such advances would shrink a heavy-duty car battery to
size of a coin, had this been possible for batteries.
Will the fuel cell replace the battery?
More than 2,000
organizations throughout the world are actively involved in the fuel
cell development. There is a good reason for this - it's a great
concept. And yet, since its invention in 1839 by Sir William Grove, the
fuel cell has made little impact in our daily lives so far. In
comparison, the internal combustion engine, a development that began at
about the same time as the fuel cell, has far broader use.
The fuel cell was used in
the Gemini space program in the 1960s, followed by trial runs in buses
and cars during the 1990s. One of the main obstacles is high energy
cost. The cost-per-watt. must be reduced by a factor of ten to become
competitive with other sources, such as the internal combustion engine.
The improvements of the
fuel cell during the last 10 years have been moderate. Attempts to
mass-produce have failed, even though four public North American fuel
cell companies have raised over a billion dollars in public stock
offerings from 1999 through 2001. Unlike other investments that paid
early dividends from product sale, returns on fuel cell lies years
ahead. Today, 45% of the money raised by the four fuel cell companies is
lost.
Fuel cell advocates are
promoting a technology that is intended to replace the battery but the
opposite is occurring in mobile and portable applications. The fuel cell
has a defined power band in which it operates efficiently. Outside this
band, the fuel cell loses effectiveness. Sluggish start-up when cold and
limited loading are other limitations. Until resolved, the fuel cell
will serve as the generator to charge the batteries that do the driving.
There are also problems
with the longevity of the stack. The membranes, the core of the engine,
degenerate too quickly. The replacement of the stack is a major expense.
Until these problems can be resolved, the fuel cell will be reserved for
specialty applications, such as providing power (and water) for space
vehicles and submarines. Here, no combustion is possible and toxic
exhausts cannot be tolerated.
Experts believe that the
fuel cell, as we know it today, would only be implemented in vehicles if
the supply of fossil fuel is exhausted or if mandated by law due to
environmental concerns. Comments have been made that the fuel cell may
never become the engine of choice for mass-produced cars. This is in
line with the notion that the steam engine of the 1800s was never
intended to propel airplanes.
Continuous improvements in
the fuel cell are being made but the results are slower than with other
technologies. Eventually, the fuel cell will find important niche
markets that dwell outside the domain of the polluting internal
combustion engine. Should a major break-through occur and the fuel cell
does become an alternative power source, the world would become a
cleaner place and humanity would be thankful for it.
What is the ultimate
miracle battery?
The ultimate miracle
battery is still nowhere in sight and the battery remains the 'weak
link' for the foreseeable future. As long as the battery is based on an
electro-chemical process, limitations of power density and short life
expectancy must be taken into account. We must adapt to this constraint
and design the equipment around it.
People want an
inexhaustible pool of energy in a small package that is cheap, safe and
clean. A radical turn will be needed to satisfy the unquenchable thirst
for portable and mobile power. It is anyone's guess whether a superior
electro-chemical battery, an improved fuel cell, a futuristic atomic
fusion battery or some other groundbreaking energy storage device will
fulfill this dream. For many, this break will not come in ones lifetime.
References: The Roethle
Group, Inc, USA www.theroethlegroup.com |