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OBITUARY: KATHYRN BULLOCK, 1945-2021

Kathryn Bullock one of the greats in the electrochemical history of the lead battery has passed away aged 76.

Mapping out the landscape for future generations of lead research

It is with sadness we record that Kathryn Bullock, one of the giants of the electrochemistry of lead and batteries in general, passed away on May 17.

She was widely admired for not just her encyclopaedic knowledge of VRLA batteries but as a sunny, friendly and an engaging person. She was a regular speaker on behalf of the research side of the battery industry. Lead veteran Gene Valeriote recalls: “Kathy was ebullient, generous and an electrochemical genius. She was simultaneously a friend as well as a colleague. I first met her when she was a secretary/ technician at Gates— the pioneer of the VRLA battery — where she got so absorbed into what was going on, she left and returned with a doctorate!”

David Rand, also a Gaston Planté award winner, recalls how they both came out of the gala dinner of the Electrochemical Society in New Orleans singing songs from Oklahoma and dancing down a crowded pathway.

Her many achievements include becoming the first ever female president of the Electrochemical Society in 1996 and also winner that year of the lead battery industry’s highest accolade, the Gaston Planté Medal Award.

The award recognized Bullock’s contribution to the lead battery world for her discoveries of: • the self-discharge processes in VRLA batteries and their impact on shelf life and discharge capacity; • the structure and properties of the corrosion layer on Pb, Pb-Sr and Pb-

Sb electrodes; • how the corrosion layer of the positive plate on a solid-state Pb/PbO/

PbO2 element with an emf (electromotive force) of 0.8V can be formed and its effect on the polarization of the positive plate; • the beneficial influence of H3PO4 on the positive plate of lead acid batteries; • the influence of antimony on the negative plate; • how tridimensional E-pH-pS diagrams of Pb/H2SO4/ H2O could show thermodynamic values for open-circuit voltages, acid activities and lead sulfate solubilities; • the recombination efficiency of the oxygen cycle in VRLA batteries; • new conductive materials and processes to enhance lead battery formation; • the possibility of perovskite coating of the lead current collectors in positive plates to reduce corrosion.

She was the author and co-author of more than 60 scientific papers, chapters and books and has 11 US patents in battery, fuel cell and capacitor technology.

Norma) Kathryn Rice was born in Bartlesville, Oklahoma on September 24. 1945. An early interest in chemistry developed into a degree at Colorado University and in 1967 (freshly married to Kenneth Bullock who later became a minister), she applied to Gates Rubber Company where she was interviewed by John Devitt, the driving force behind the VRLA battery, who was organizing a battery development group.

She left to move to Chicago to get her doctorate before returning to Devitt whose team had by then developed the VRLA battery.

The push was on to test and refine the design and develop the manufacturing processes. The first application of the Gates VRLA AGM battery was in power tools.

Lead-acid batteries with silica gel added to the acid could be used in some portable applications, but the gel limited the power. Portable power tool companies were interested in the VRLA cells because of lower materials costs and higher voltages and power. Although lead is heavier than nickel and cadmium, they could use three lead-acid cells to replace the voltage of a battery of four nickel-cadmium cells. When lead-acid batteries are discharged, the state of charge decreases as the acid concentration decreases.

Many stationary lead-acid battery applications, such as standby backup power, required regular monitoring of the acid specific gravity with a hydrometer to determine the energy left in the battery. A sealed cell was not acceptable for these critical applications.

With her background in computer modelling and physical chemistry, Bullock was able to develop a model and numerical tables that would allow customers to convert the open circuit voltage of a VRLA battery to the acid concentration and battery state of charge. She was also able to use thermodynamic data from the literature to correct the state of charge for the internal battery temperature.

She later recalled: “To maintain my skills and increase my knowledge of lead acid batteries, I began reading articles in the Journal of Electrochemical Society on corrosion reactions at the lead-acid positive grid by Paul Ruetschi, Jeanne Burbank, Detchko Pavlov, and others. With electrochemists from local universities, I also founded a local chapter of the Electrochemical Society.”

In an evening graduate course on corrosion at the Colorado School of Mines, she learned about potential - pH (Pourbaix) diagrams. Since positive grid corrosion reactions are dependent on both sulfate (S) and hydrogen (H) ion concentrations at the corrosion interface, she developed a threedimensional potential/pH/pS diagram that could be used to better understand and reduce the corrosion of the positive

Kathryn working in the Johnson Controls research laboratory studying cyclic voltammograms of lead in battery acid containing phosphoric acid

lead grids. In 1977, she accepted a job at Globe-Union, a large battery company in Milwaukee that was to become part of Johnson Controls. She worked there for nearly 15 years, first as a research scientist and then, beginning in 1980, as manager of the battery research group. “We worked on many different kinds of lead-acid batteries, including flooded, gelled and acid-starved designs for all types of automotive, stationary, and portable applications,” she said later.

At Gates, Bullock had worked on a project to determine how much phosphoric acid should be added to the VRLA battery electrolyte and had presented a paper on her results at an Electrochemical Society meeting.

Phosphoric acid was added to lead acid gel batteries to increase their cycle life. She used cyclic voltammograms to study the effects of phosphoric acid on lead battery reactions. Based on her cyclic voltammetric data, the amount of phosphoric acid added to the Gates cells was reduced to a very low level.

At Johnson Controls, she continued to study phosphoric acid effects on the positive electrode in lead-acid batteries and published additional work on the subject. In 1980 the Electrochemical Society Battery Division presented Kathryn Bullock with its research award for this work. Bullock’s research group was partially funded by the US’ Department of Energy to work on electric vehicle and load levelling batteries.

The battery research group also supported development work on nickel-metal hydride and zinc-bromine batteries. She began to file patents at Johnson Controls on her ideas of ways to improve lead-acid battery performance and on ways to decrease battery production times.

One of her first projects was to find an alternative way to make a dry charged battery. Johnson Controls had a method of charging an acid filled battery and then dumping out the excess acid and centrifuging the battery to eliminate as much moisture as possible. Unfortunately the shelf life of this battery was not as good as for drycharged batteries due to the residual acid left in the battery.

The Johnson Controls battery division had a solid engineering department, along with a technical library, a materials research group and an analytical group that provided very good support for battery research and development.

Many of their projects were cosponsored by the US’ Department of Energy. The two built a new R&D laboratory and worked on lead-acid, zinc-bromine, and nickel metal hydride battery development projects for applications such as load levelling and electric vehicles.

Bullock and her colleague Bill Tiedemann assembled a top notch R&D team and soon built a new world-class R&D laboratory (that later morphed into JCI’s Battery Technology Center). “Back then we were working on many of the right subjects such as grid corrosion, battery thermal management, EV batteries, grid design, plate curing and even load-levelling,” she recalled.

“I’ll never forget our work designing the new lab and purchasing some of the first computer controlled battery cyclers from Bitrode (and it was all done without email)!

In 1991, AT&T Bell Labs asked her to lead the move of their battery group from Texas to New Jersey “At AT&T I had an opportunity to get more experience in systems engineering and worked closely with systems engineers and battery companies to develop new battery designs. AT&T also agreed to let me accept a nomination to run for vice-president and then president of the Electrochemical Society.”

They worked in Dallas for five years, until Bell Labs became part of Lucent Technologies.

At that time Medtronic, Inc invited Bullock to lead a group developing an aluminium electrolytic capacitor design and factory and designing new lithium primary batteries for implantable medical equipment.

In 1996, she was awarded the Gaston Planté medal — perhaps the most prestigious award in the lead acid battery business. At the end of 1999, she accepted a position as executive vice president of technology at C&D Technologies in Philadelphia. In 2003, she founded a consulting business called Coolohm, Inc where she was at the cutting edge of various new projects. For example, in some new lead-acid battery designs, higher levels of carbon are being added to the negative plate materials.

A committed Christian, her life has been based on the belief that science and faith are not incompatible and our duty is to push back the borders of our understanding as far as we can — and impart that wisdom and knowledge to others.

Her last few years, however, were plagued with ill health. Her death marks the end of a true battery pioneer and brings to a close not just the life of this remarkable woman but a period when remarkable advances in lead battery storage were not eclipsed by the threat of the competition from alternative chemistries.

Battery luminaries all. Taken at 8ELBC in 2000 Seated is Alfred Meissner of Digatron, Germany. Standing from left to right are Paul Ruetschi, Patrick Moseley, Kathryn, Juergen Garche, and husband Ken

“Kathy was ebullient, generous and an electrochemical genius. She was simultaneously a friend as well as a colleague”.

A 2009 photo taken with Ken