Detchko Pavlov, 1930-2017

Detchko Pavlov, scholar, academician and probably the greatest expert on the lead battery that has yet lived, died on the morning of August 25. He was widely respected, widely liked and one of the leading figures in advancing our knowledge — both theoretical and practical — of the electrochemical workings of the battery.

Many senior figures have paid tribute to him as both a man and a scholar.

David Prengaman, chairman of RSR, told Batteries International: “I have been blessed to have several people over the years aid me in my career and my love affair with lead acid batteries. Detchko Pavlov was one of them.

“While I had heard of Pavlov, it was not until the beginnings of ALABC that I met him. He had a way of explaining his theories of active material to me in the simple examples that even a materials person such as I could understand. I remember many discussions with him and my wonder of his understanding of the subtle nuances of charge and discharge reactions.”

Boris Monahov, program director for the ALABC and former student and eventually colleague of Pavlov, said: “Detchko was a very humble person and never took himself too seriously. In fact he had a brilliant sense of humour and often made jokes at his own expense. After all these 25 years I spent with him I felt that he was both my teacher and my relative — I spent more time with him than with my parents. I recall with fondness the discussions we had in the lab after work was over, or on Saturday when all the administrative and other noises were off.”

His intellectual prowess and knowledge of his subject was legendary. “Detchko? He’s forgotten more about lead than I’ve ever known!” said John Devitt, inventor of the VRLA battery and hardly an intellectual slouch himself.

“He was an outstanding researcher and scientist with a highly individual approach to the subject of his studies. One of his talents was his patience and ability to move step by step in understanding the mechanisms that underpin how batteries work,” said Monahov. “He was able to explain such mechanisms simply. He liked saying: ‘science is a simple thing but it’s not for simple people.’

“He helped 10 of scientists to design their research, prepare their theses and develop their careers. He helped thousands of battery engineers with his books and lectures and helped his colleagues to resist, survive and flourish in a public environment not always generous and friendly to research teams. He was a great man.”


Detchko Pavlov was born on September 9, 1930 in Shipka, a sleepy town in Central Bulgaria nestling at the foot of the Balkan Mountains.

He and his sister attended the local Saints Cyril and Methodius grammar school in Kazanlak, where their mother taught mathematics and physics and their father taught in the primary school.

In 1946, when Detchko was 16, a young chemistry teacher visited their school. He taught the students how to work out chemical equations and demonstrated various chemical experiments. For the young Pavlov this was an epiphany, which inspired him to study industrial chemistry.

During the next two years, Detchko was the star pupil. For his excellence, he was selected to be the school standard-bearer in his final year. His sister at the time said he was “a serious tidy boy, fond of books and very determined to do well”.

His academic career started in 1948, when he obtained a place to read chemical engineering at the State University in Sofia. In 1953, after graduating with a degree in electrochemistry from the Higher Institute of Chemical Technology and Metallurgy in Sofia, he was invited to join the department. It was headed by professor Stefan Hristov, a pioneer in the application of quantum mechanics to electro-chemistry.

In the same department working alongside him as an assistant professor was a shy, pretty girl, Svetla Raitcheva, who had just completed her higher education at the D Mendeleev Chemical Technical Institute in Moscow. She already had a reputation for academic brilliance and a fearsome intellect.

Their scientific collaboration grew into a friendship and ultimately, marriage. Svetla went on to earn her PhD in quantum chemistry and became first an associate professor and then a full professor. (She eventually chaired the Department of Physical Chemistry and also became head of the institute.) Svetla was to be the love of his life, and he was devastated when she died a few years ago.

At the 1960 National Congress of Chemists, Pavlov had reported the results of his research into polarography. Impressed, academician Kaishev, director of the department of electrochemistry at the Bulgarian Academy of Sciences, invited Pavlov to join the department.

It was an auspicious time to specialize. Bulgaria had begun to concentrate its manufacturing efforts in the production of electric forklift trucks and Pavlov was assigned the task of improving lead-acid batteries.

For the next half century, working on the fourth floor of Building 10 on the Bulgarian Academy of Sciences campus, Pavlov and his team of some 25 co-workers — the best graduates from the University of Chemical Technology and Metallurgy and the Faculties of Chemistry and Physics of the Sofia State University — broke new ground in understanding the processes at work in a battery.

In 1961, Pavlov obtained a one-year posting at the Institut du Radium, Marie and Pierre Curie Laboratory in Paris, France working for the laboratory director, professor Haisinski, who had once worked with Marie Curie. Haisinski directed Pavlov towards research on the chemistry of complex anode processes, in particular moving research into practical applications.

LABD formation

In 1967, Pavlov and his colleague professor Evgeni Budevski established the Central Laboratory of Electrochemical Power Sources (CLEPS), in which he became the head of the Lead Acid Battery Department (LABD).

Following the discovery of rich deposits of lead ores in southern Bulgaria in the mid-1960s, the country became the major supplier of forklift trucks and batteries to the USSR and other eastern bloc countries. Alongside their scientific research, the LABD scientists actively supported the Bulgarian battery industry with new technologies, transfer of knowledge and genuine theoretical modelling.

For example, Pavlov and colleague Vasil Iliev proved that when polymer additives are added to the battery, its power at low temperatures increased.

Their scientific contribution paid off. The starter batteries produced in the Bulgarian “Start” factory in Dobritch continued to work well in freezing and sub-zero temperatures.

With Yugoslavia, Czechoslovakia, East Germany and Tyumen unable to provide anything comparable, Bulgarian batteries were bought in large quantities, starting at 300,000 units and rising. In return, Bulgaria received 12,000-15,000 automobiles per year from the Zhiguli-Lada factory in the Soviet city of Toliati.

The range of studies conducted by Pavlov and his team was extensive. These included: the kinetics of electrochemical processes; electrochemistry of lead electrodes; semiconductor properties and structure of lead oxides, lead sulphate and basic lead sulphates; processes related to the all stages of the technology of battery manufacture including paste mixing, curing, drying, pickling, formation; structures of lead and lead oxide active masses; processes taking place inside the battery during its storage, operation and rest; electrochemistry of antimony and tin electrodes; processes of oxygen evolution and its recombination back to water; thermal phenomena in VRLA batteries and the mechanism of the processes causing thermal run away in VRLA batteries; degradation processes and ways to suppress or avoid them.

Of special note was the way Pavlov and his team investigated the way in which expanders affected the performance of negative lead acid battery plates and how they could be improved.

This led to the creation of a new generation of highly efficient organic ligno-sulphonate expanders. The team also revealed the mechanism of the processes taking place in the AGM separator and developed a modified, better AGM battery with programmable properties.

In consequence, Pavlov and his team were granted 33 patents, in Bulgaria and abroad. He also developed a lecture course “Processes that occur during battery manufacture” and “Essentials of Lead Acid Batteries”, which he presented in numerous countries worldwide.

A second family

And with his research came international acknowledgement as Pavlov’s team’s work was recognised for its worth.

One of the more charming characteristics of Pavlov — who had a reputation for being a modest, easy-going person — was the way that he never distinguished his work from that of his team. Indeed, when his wife was alive the two often referred to the team as their second family.

“He was extremely proud of his team at CLEPS and fiercely protective of them as his children as he had none of his own. With the change from Communism, he was forced to get support from outside the state to support his research. Given the opportunity but little in funds to travel, he managed to travel extensively to conferences and battery companies throughout the world, always trying to obtain project funding for his laboratory,” said Prengaman.

Pavlov was awarded a Doctor of Science degree in 1984 — a belated qualification. Fully occupied at CLEPS, he had been unable to find the time to make a conventional approach. So when he submitted his thesis, the Scientific Council of Physical Chemistry — the toughest in Bulgaria — agreed that this was not merely a PhD work, but something much bigger. They awarded him a DSc.

From 1988, he was the driving force behind the success of the LABAT series of conferences — he chaired 10 of them — which have since been held every three years. As testimony to their importance, the proceedings of these meetings have been published as special issues of the Journal of Power Sources.

He was a member of the editorial boards of five international journals published in Switzerland, India, Russia and Bulgaria.

He also influenced the decision of the Bulgarian Academy of Sciences to award battery scientists and experts with the Gaston Planté medal for outstanding contributions. Up to now, 17 battery veterans from a range of countries have received this award.

In the early 1990s with the Republic of Bulgaria undergoing rapid democratic changes — and the economy being hit by rising inflation and falling standards of living — Pavlov realized there was a risk that the department he had been building up for more than 25 years could fall apart. He introduced what he called “the American approach to science” — essentially using commercial partners to boost his research efforts.

Before long he had persuaded international concerns such as Varta Research in Germany, ALABC in the USA, and Oerlikon in Switzerland to offer his department remunerative several-year contracts to develop production technologies.

Pat Moseley, a former manager of the Advanced Lead Acid Battery Consortium, said: “Detchko led his strong team in the scientific study of lead–acid batteries without the financial advantages of his contemporaries in other parts of the world. He was a true gentleman and a dedicated scientist. The work and the spirit of Detchko will stay alive after his unprecedented scientific career through his papers.”


In 1997 he was elected a full member, or academician, of the Bulgarian Academy of Sciences. This is the highest scientific rank in eastern Europe. It is only when one academician dies that a new one can be elected.

That year he also became adviser and cooperative member of the ITE Battery Research Institute, Nagoya, Japan.

Pavlov and his team — research scientists Geno Papazov, Stefan Ruevski, Temelaki Rogachev, Boris Monahov, Galia Petkova, Mitko Dimitrov, Plamen Nikolov, Maria Matrakova and others wrote extensively and some 195 papers have been published in international scientific journals. To date, these have been cited more than 2,700 times in scientific literature worldwide. Often just one of these papers would go through as many as 16 drafts before he was satisfied.

His last work Lead-Acid Batteries, Science and Technology, Second Edition: A handbook of lead-acid battery technology appeared just a couple of months ago.

The value of Pavlov’s contribution has been acknowledged through a series of awards and honours: 1976, The Cyril and Methodius Medal; 1980, The Award of the Federal Ministry of Australia; 1984, The Research Award of the Electrochemical Society; 1986, The National Dimitrov Award for Science; 1994, The Gaston Planté Medal; 1995, The International Cultural Diploma of Honor; 2006, The Marin Drinov Medal with Ribbon – the highest award of the Bulgarian Academy of Sciences; The ILA Lifetime Award 2010; and most recently, NAATBatt’s Lifetime Achievement Award.

Admirers say the genius of Pavlov was in the way he could pinpoint where a problem might be occurring in, say, a piece of battery production or use, and then strip the processes down to fundamental methods. Once the process was defined he was also famous for the clarity of his writing, so that not just academics but any production engineer could use it to their practical or theoretical ends.

But all who knew him had anecdotes to tell about Pavlov the man. “’Detchko’ is the Bulgarian word for ‘kid’,” says Paolina Atanassova, R&D manager at Cabot Corporation. “And he had some of those passions and enthusiasm. I remember in April 2011 when I arrived at the Institute’s conference room to work through power point presentations, data, results and the like. Detchko smiled and asked if the Wi-Fi TV connection was good — he wanted to watch the wedding of Prince William and Kate. He was excited as a kid. ‘Polarization curves can wait,’ he told us. ‘This is a love story and a fairy tale, a once-in-a-lifetime opportunity to see something so beautiful.’”

Kevin Desmond, a historian who wrote a chapter in a recent book on Pavlov, recalls: “His passion was to find out as much as he could about the world in which we live. So in his extensive travels, he would always spend extra time sightseeing, taking photographs and getting acquainted with the host country and the people. Another passion, less well known in the conference circuit, was his love of classical music and pop music from the 1960s and 1970s.”

David Rand, an industry veteran and former head of the ALABC, said: “I still recall my first meeting with Detchko. It was in 1980 and he was on sabbatical leave at Flinders University in Adelaide. We were attending the EVE-80 Conference and Electric Vehicle Exposition organized by the South Australian Energy Council. We were in a car park on top of one of the university buildings, where a number of EVs were on display. Detchko was invited to drive an Enfield 8000. Without hesitation, he jumped into the car and zig-zagged around the other vehicles in a cavalier, but alarming, display of steering and then hurtled down the ramp to the street, several storeys below.

“I believe he was rescued sometime later after the battery had become exhausted.

“Many years later on the occasion of LABAT 1, he picked me up from the airport in Sofia in his Trabant… his style of driving hadn’t changed!”

Pavlov died just days before what would have been his 87th birthday. After recovering from a heart operation earlier in the summer, he suddenly contracted a high temperature, and the doctors were unable to overcome the fever.

“He loved many things in life: his beloved wife, his cottage in the mountains, his colleagues at CLEPS, teaching people how to build better batteries, and lead acid batteries. I will miss him very much,” says Prengaman. “The battery industry will miss him, his friends throughout the world will miss him, but most of all lead acid batteries will miss him.”

Requiescat in pace, Academician Detchko Pavlov.