For almost half a century, Jim Sudworth of has been on a mission — often a bumpy one — to make a scientific and commercial success of the sodium battery. Kevin Desmond recounts his story.

Pioneering days and the joys of sodium

cience is not a profession for the faint-hearted. In addition to the ability to take good ideas forward, success requires determination, perseverance and, in Jim Sudworth’s case — from his early post-graduate work trying to synthesise hydrogen cyanide to his ground-breaking research on molten salt batteries — a healthy respect for safety.

James Sudworth was born in January 1939 in Ashton-in-Makerfield, near Wigan in the north of England. His father was a foundry worker. It was at Ashton grammar school, that the chemistry teacher inspired Jim with an enthusiasm for this subject. Leaving school at 16, Jim obtained a job as a technician at ICI Widnes, working in the analytical chemistry laboratory.

Although he had left school early — or what we would call early nowadays — he had ambitions to advance himself. He also studied on day release at Widnes Technical College for the Royal Institute of Chemistry (now the Royal Society for Chemistry) qualification.

At the same time, and unusually for the 1950s when most Britons rarely crossed the channel abroad, he travelled widely across Europe using his passion for cycling to power his way across the continent.

After graduation, he worked on the synthesis of hydrogen cyanide which is a key raw material in the manufacture of polymethyl methacrylate (Perspex) at the laboratory and pilot plant scale.

1962 was a big year for him. That year he married Sheila, after a three year courtship. They have four children, two boys and two girls.

It was also the year that first brought him into professional contact with sulfur, the periodic element that was to dominate most of the rest of his life. Between 1962 and 1963, Sudworth was employed as a scientist at Schenectady Midland, a tar distillery, in Wolverhampton. “I worked on the removal of sulfur from phenols by solvent extraction of a solution of their sodium salts, taking the process to the pilot plant scale,” he recalls.

From 1965 to 1967, he worked at Chloride — one of the biggest names in batteries at that time — at its plant at Swinton. He was fortunate too in that he worked for Ken Peters, who was himself later to became a batteries legend [see Batteries International issue 81]. Sudworth worked on sealed nickel cadmium cells and then on the stability of the platinum electrode in the hydrazine/air aqueous fuel cell.

Perhaps his biggest break — and certainly one that was to affect the course of his life — came in 1967, when he joined British Rail. “They were opening a new research centre in Derby and advertised for electrochemists. Their plans were exciting they were interested in developing a new battery, for powering locomotives, the sodium sulfur battery.” This had followed the news that two US researchers working for Ford Motor Company— Neil Weber and Joe Kummer — had demonstrated a major “breakthrough in developing a feasible power source for electric vehicles,” according to an announcement in October 1966.

Meet the team: the vehicle used to test the sodium sulphur battery at British Rail. Sudworth fifth from the left, Roger Tilley, sixth, and Hamish Duncan far right.

“The heart of the new system is a Ford-developed crystalline ceramic electrolyte composed largely of aluminum oxide and based on a material known as beta-alumina,” the company said. “Further development of the Ford battery should lead to an economical, rechargeable battery system which, when adapted to a vehicle would provide greatly improved acceleration and range capabilities than now available from existing batteries.”
This was the start of a long-term engagement by the company into the use of the chemistry in electric vehicles and culminated in the Ecostar program, led by Malcolm Shemmans in the early 1990sm where a test fleet of over 100 cars were powered by the sodium sulfur battery.

Sudworth’s first task was to build and test a cell and try and replicate the results of Kummer and Weber. To do this he needed the ceramic electrolyte, beta alumina. “I found out that a ceramicist at English Electric, Hamish Duncan, was working on ways of eliminating this from alpha alumina ceramics used as radomes as it was an efficient absorber of radio waves.

“I persuaded him to join me at BR and by creating the opposite conditions to those he used to eliminate beta alumina, he was soon able to fabricate ceramic discs from the material. At this point, the acting head of the electrochemistry section was promoted and I was offered his job.”

During the next 15 years, based at the British Rail Technical Centre in London Road, Derby, Sudworth was responsible for directing a team of 20 to 40 scientists and technicians in the development and production of beta alumina, cells and batteries.

So what were the initial and practical challenges for sodium-sulfur battery-electric trains to replace diesel trains?
“When we looked at what the characteristics of a battery needed to power a locomotive would be, it was clear that it would have to store several megawatt hours of energy,” he says. “And it had to be recharged in a couple of hours. Even for the sodium sulfur battery, that was a huge challenge.”

The BR team came up with the idea of a hybrid locomotive, with a diesel engine running at constant speed and maximum efficiency and the battery taking care of the peak power requirements. They built several batteries but never got to the point of installing them in locomotives (although over 20 years later, General Electric did build a hybrid locomotive using a different type of sodium battery as described below).

One major problem that had to be overcome was to make the sodium sulfur battery safe enough to use in mobile applications.

In 1971 Sudworth took out his first patent. Then in 1973, with John Gibson who worked for him at BR, he wrote his first book: “Specific Energies of Galvanic Reactions and Related Thermodynamic Data.” It was published by Chapman & Hall.

In the years to come, Jim Sudworth would write numerous papers and as inventor/co-inventor take out numerous patents on high temperature batteries.

So what were the milestones at BR Research?

The first milestone was to reproduce the results of Kummer and Weber, which we achieved in 1969. The next milestone was to build a battery. We weren’t the first to build full size battery capable of powering a vehicle. That was achieved by Wynne Jones and his colleagues at the Electricity Council in the UK, who installed it in a Bedford van. Subsequently, however, we developed a high rate sulfur electrode capable of rapid charging, came up with the safety features which overcame the tendency for these batteries to catch fire, and overcame the problem of short cycle life and increases in the internal resistance of the battery over its life.”

Abruptly, in 1981, the project at BR was closed down before Sudworth and crew could test their battery on trains. BR had been in a cooperative government supported programme with Chloride Silent Power (CSPL) and AEA Harwell. CSPL decided to tie up with General Electric, which was also developing the battery. This resulted in the breakdown of the cooperative agreement and ended BR’s rationale for continuing development of the battery.

Sudworth says: “I suggested to Hamish Duncan and another of my colleagues, Roger Tilley that we should go for a management buy-out and to continue developing the battery for other organisations. We went public and as a result were approached by companies interested in funding the development. We were also approached by Ron Dell who was in charge of Harwell’s battery programme.

“He told me that they had been using beta alumina tubes we supplied them on a separate battery programme funded by DeBeers, the South African diamond mining company and Anglo American. Dell introduced us to Roger Wedlake, the DeBeers programme manager.”

Sudworth led the negotiations with Anglo American which culminated in the signing of an agreement to do contract research on a new battery and in the formation of Beta Research & Development Ltd in January 1982.

Up to this point, Anglo American had refused to disclose what the new battery system was, but the agreement included a six-month contract to develop the battery for them.

On the basis of this, Sudworth and his two colleagues persuaded the key members of the BR team to join the new company. “BR were generous enough to lease us the laboratory we had been working in and to sell us all the equipment,” he says.

On January 4 the new team assembled in their lab to meet Johan Coetzer, the inventor of the new Zebra battery and to hear what it was they would be working on.

“This turned out to be the sodium/metal chloride battery, which then was in a very early stage of development, so much so that I couldn’t imagine how it could be commercialized and was convinced that it would be abandoned by Anglo American in favour of the sodium sulfur battery.

“We soon realised the potential of Johan’s invention and in cooperation with his group in South Africa and Harwell, we went on to commercialise it.”

As chairman and managing director, Sudworth was responsible for all aspects of the development of the Zebra battery and its transfer to production. The first challenge was that the positive electrode was fabricated by passing chlorine over an iron/carbon body — not exactly a practical commercial process,” he says.

“Moreover, the cell could only operate in a narrow temperature range. Two key developments were to change the metal to nickel and to build the cell fully discharged meaning that the positive electrode was a sintered body of nickel and salt and no elemental sodium was necessary. The nickel electrode had a wide operating temperature range as well as a higher voltage.”

Within 18 months Sudworth’s team had built a sodium/nickel chloride vehicle battery and in 1987 Anglo American, who by that time had exercised their option to buy Beta Research & Development Ltd, started a collaboration with AEG.

The next challenge was to increase the specific power of the battery to meet Daimler’s requirements for passenger car operation. This was achieved by changing the round beta alumina tube to a clover leaf cross section tube and changing to a mixed nickel/iron positive electrode.

In 1984, Zebra Power Systems (ZPS) was formed in South Africa from the CSIR team. A multi-kWh battery was tested in a vehicle.

In 1985 with Roger Tilley, Sudworth co-wrote the seminal book “The Sodium Sulfur Battery”, published by Chapman and Hall; a Russian edition was published in 1988.

In 1986 further advances were made in particular the development of 30kWh and 50kWh Na/FeCl2 batteries and a 30kWh Na/NiCl2 battery was tested by Daimler Benz engineers. Sudworth was part of the team that negotiated the joint venture agreement and was responsible for ensuring that the battery-powered Suzuki van met the performance parameters that Anglo American had given to Daimler-Benz.

In 1989 Anglo American Corporation formed a joint venture company with AEG with the aim of industrializing the Zebra battery. At that time AEG was being absorbed into Daimler-Benz who evaluated the battery for electric vehicle applications.

The DB team led by Dieter Sahm suggested a re-designed cell with a higher power to energy ratio than the 100Ah cell then being used. AEG Anglo Battery Holdings (AABH), a joint venture company was formed to industrialize the battery.

Between 1990 and 1995 Daimler-Benz’s fleet of Mercedes cars, using Na/NiCl2 slimline cells, totted up some 100,000km of road testing. During this time, energy and power was improved and pilot lines went into operation in the UK and Germany.

Tilley and Sudworth outside the Beta Research headquarters.

Beta R&D, under Sudworth’s supervision, developed a high-power cell (monolith) which was transferred to pilot lines.

By 1997, alongside a new generation of batteries (>150W/kg) suitable for series production, the 80 Zebra-powered test vehicles had completed 1.6 million kilometres. By 1998 AAB had taken the development of the Zebra battery to the point where it was ready to be put into production.

“The pilot lines in Derby and Berlin were producing batteries at the rate of up to 20 per month, the electric vehicles were performing very well and the customers were pressing for a commitment for volume production,” he recalls. At that time however, the two parent companies of AAB were redirecting their strategies away from peripheral activities and towards their core businesses. For a time it looked as though the project would be terminated.

Then in 1999, a Swiss company called MES-DEA acquired the Zebra technology, including the production and development equipment and Beta R&D, Sudworth remained as the managing director to oversee Beta’s role in support of MES-DEA’s plan to re-locate battery production to a new factory in Switzerland.

Beta took over the former AEG Anglo Batteries ceramic plant in Derby and recommenced beta alumina production. MES-DEA set up a factory in Stabio, southern Switzerland. By September 2002, having installed larger equipment, including moving the positive electrode plant from Derby, the Stabio factory was set up to manufacture 900 batteries per year, with an eventual target of 33,000 batteries/year depending on market demand.

Meantime, in July 2001, Sudworth retired and Roger Bull took over as managing director.

But retirement didn’t last long — especially since there was still so much more to do. “In April 2003, I was invited by my former colleagues to lead the management buy-out of Beta R&D from MES-DEA and to take the job of research director because by then it had become clear to us that Carlo Bianco, the owner of MES-DEA, wanted to bring all the battery work together in Switzerland including the R&D and would close down the UK operation.

“Roger Bull, Roger Tilley and myself thought that we could make a business doing contract research on sodium batteries. I negotiated an agreement with Bianco for Beta Research and Development to become the UK agent for their sodium/metal chloride batteries and Beta once again became an independent company.”

In January 2003, Sudworth was awarded the Earnest Yeager Memorial Award from the International Battery Association. He received this at the IBA-HBC Earnest Yeager memorial symposium in Hawaii. “For outstanding contributions to the development of sodium metal chloride (Zebra) batteries.”

As an independent company, Beta R&D was then able to widen its scope to include R&D contracts with government, EU, and commercial companies.

“Under the UK government contracts we developed with our UK partners, a sodium metal chloride battery for down-hole operation in the oil and gas industry,” Sudworth says. “This included a hybrid power source comprising a solid oxide fuel cell and a sodium metal chloride battery. Under one of our EU contracts, we developed a high power version of the battery for hybrid vehicle operation.

“In the commercial field we worked with Rolls-Royce to provide a sodium metal chloride battery to power a NATO rescue submarine which is now in operation, and we did subcontract research for GE’s Global Research Centre on their hybrid loco project.”

In September 2007, Beta R&D was acquired by General Electric Transportation Division, and is assisting in the development of sodium batteries for telecom, UPS, hybrid locomotive and utility applications (see cover story).
In 2010, GE Energy Storage invested over £1.7 million ($2.6 million) and created more than 50 new jobs at its Durathonbattery research facility in Burton-on-Trent as it expanded its battery technology into new applications.
Today, Jim Sudworth, after over 40 chequered years, is still working towards the ultimate success of Beta’s sodium/metal chloride battery programme.

Asked what hobbies he has, he laughs. “I’ve only one hobby at present and I’m being paid to do that! I do, however, support a football team: Premier league club Wigan Athletic.”

Meanwhile development continues. GE’s $100 million factory in Schenectady, New York State is up and running. At full capacity the battery factory will employ 350 people and produce 10 million cells annually.