Financial Times, 18 April 2005 - Battery manufacturers have long been told they are holding back technological ad-vance by the industries that depend on their products - computing, telecoms, consumer electronics, cars, electric utilities and many others - because energy storage capacities are increasing too slowly.

But the pace of innovation in batteries and other energy storage devices is picking up, leading to hopes that the sector will soon throw off its lethargic reputation.

Since 1990 computer disk capacity has increased 4,000 times, while energy density of rechargeable batteries has improved just threefold, says Kevin Fitzgerald, chief executive of Florida based Ener1, one of many innovative battery companies that have recently sprung up around the world.

"Because battery capacity is a bottleneck in product innovation, engineers work around the constraints when developing products," says Mr Fitzgerald.

"By developing storage cells that are light, powerful and long-lasting, companies such as ours can eliminate the energy bottleneck and enhance product development in a variety of industries."

The pressure to produce more efficient energy storage devices is taking place on three scales:

*Computer, telephone and consumer electronics manufacturers are desperate for better power sources, as they cram more battery-draining features on to mobile devices.

*Vehicle manufacturers are under strong pressure to replace diesel and internal combustion engines with electrically powered alternatives for environmental reasons.

*The electricity supply industry needs to be able to store power generated from renewable sources that are only intermittently available, such as wind and sunshine.

Batteries are much the largest and best established category of energy storage system. They represent a Dollars 48bn a year world market, growing by 6.5 per cent annually, according to Freedonia, the US based business research group.

But in government and industry circles, batteries are widely regarded as boring, in contrast to fuel cells, a relatively novel technology that receives a lot of public research and development support.

Both batteries and fuel cells release energy through electrochemical reactions. The difference is that fresh reactants are fed continuously into a fuel cell; a battery retains the same chemicals for life, though it may be recharged by driving the reaction in the opposite direction with an electric current.

The ultimately clean fuel cell runs on hydrogen which reacts with oxygen from the air to produce electricity and water vapour.

Although this sounds environmentally perfect and has already proved its feasibility in trials with buses and cars in several cities, there are formidable problems in making it work on a significant scale in the real world.

The obstacles range from the lack of a hydrogen refuelling infrastructure to the high cost and poor performance of fuel cell units, compared with petrol engines. For cars, the medium term prospects are better for "hybrid" vehicles that combine a conventional engine with fuel cell or battery power.

Some fuel cell developers are concentrating on units that run on natural gas or methanol, rather than pure hydrogen.

Although these emit some carbon dioxide, the main cause of global warming, electrochemical cells produce energy more efficiently than burning fuel in a conventional engine.

And their most important application may not be in vehicles, but to generate electricity in remote locations or even for domestic combined-heat-and-power units.

When it comes to straightforward batteries, the buzz word is lithium. Over the past decade, lithium ion batteries have taken the world of portable electronics by storm. According to Sony, world sales have reached 1.2bn units a year - as their energy storage density is superior to nickel metal hydride and nickel cadmium batteries.

Technical improvements are announced frequently to address the perceived weaknesses of lithium based batteries, for example, the fact that they wear out after being charged and recharged a few hundred times, they cannot release their energy fast enough for some high power applications, and they are slow to recharge.

Two breakthroughs in recharging speed were announced last month. Altair Nanotechnologies, a specialist Nevada based company, said lithium ion batteries made with its new electrode "nanomaterials" could be discharged fast enough to run power tools and fully recharged in six minutes.

Then Toshiba, the Japanese electronics giant, made similar claims for its new lithium ion battery which can recharge 80 per cent of its capacity within a minute and 100 per cent in "only a few more minutes".

Its breakthrough is also based on using nanoparticles in the electrode.

The market for lithium batteries is poised to move up in size to electric vehicles and static storage for electricity companies.

Also last month Mar BatScap, a French joint venture between the Bollore group and Electricite de France, unveiled its all electric BlueCar at the Geneva Motor Show.

The BlueCar - the styling of which is based on the original 1950s Mini design by Alec Issigonis - runs on an innovative lithium metal polymer battery that gives it a range of 200km before it needs recharging. Although a full recharge takes six hours, the company says a few minutes recharging would be enough to get the car safely back on the road.

Meanwhile, makers of traditional lead-acid batteries soldier on, emphasising the low cost and high dependability of their products.

The weight of lead gives them a poor energy to mass ratio but every petrol driven car still has one, because they work reliably for several years, supplying the high surge currents needed in starter motors.

There is still innovation in the lead-acid battery sector. For example DSL Dresden, a small German company, has found a way to make battery grids as engineered composite materials.

These promise to extend the life and improve the performance of heavy duty lead-acid batteries.

Although everyone associates lead-acid batteries with cars they have also been used for decades in static applications, such as providing uninterruptable back up power supplies to hospitals.

But they are not the long term answer to the growing demand by electric utilities for large scale energy storage, says Peter Bruce, chemistry professor at St Andrews University in Scotland and a leading UK battery researcher.

"Although lead-acid is well proven, its energy storage density is one-quarter to one-sixth that of an advanced lithium battery system, which means that an installation has to be four to six times larger," says Prof Bruce.

"And lead does not have an image that quite fits the picture of clean energy."

For the future of batteries, the emphasis is moving from lead, one of the heaviest metals, to lithium, one of the lightest.

Copyright 2005 The Financial Times Limited
Financial Times (London, England)