meeting report

11th European Lead Battery Conference

Hilton Warsaw Hotel
Warsaw, Poland
September 23-26, 2008

• George H. Brilmyer, Ph.D.
• V.P. Business Development, North America
• Atraverda Ltd.

The European Lead Battery Conference celebrated its 11th year with more than 550 delegates in attendance from almost 50 countries. The conference organizers did a fantastic job by selecting Warsaw as the location for this bi-annual event. The city had loads to offer in terms of historic sites, city tours and restaurants. The technical program consisted of more than 50 papers by industry specialists. The conference itself covered a broad mixture of tech-nical topics. Session titles included Markets, Materials & Safety; Suppliers Shop Window; Advances in Technology; Lead Power for Hybrid Electric Vehicles; Energy Storage for Renewable Power; and Advanced Automotive Batteries.

There was also a technical poster session for those presenters who were not able to get into the already full technical program. A €500 prize was given to the best poster as determined on technical merit by a select panel of judges. The poster session prize was awarded to Dr. Joseph Cilia of the University of Malta. During the conference, Dr. Patrick Moseley presented the 2008 International Lead Award to Dr. Allan Cooper who has made many outstanding contributions to the battery industry over his 40-year career.

The conference was preceded by a tour of the Zap Sznajder Batterien plant in metropolitan Warsaw. The visitors were well received and got to see a state of the art battery plant complete with continuous plate making. If you were not at the Zap battery plant tour, you were most likely involved in the ALABC Steering Committee Meeting which took place on Tuesday, a day before the conference got into full swing. The 11th ELBC Trade Show was also well attended with more than 75 industry suppliers from around the globe. In this meeting report I have included several photos of these suppliers, their tradeshow booths and potential customers.

On Thursday the gala conference dinner was held at the Warsaw Technical University. We were all very surprised to find that the venue was a spectacular multi-level ball- room. The dinner guests enjoyed international cuisine with a synchronized serving staff that was completely amazing. The dinner concluded with music and dancing enjoyed by all. The big announcement at the end of the evening was the location of the 12th ELBC which will be held in Istanbul, Turkey on September 21-24, 2010. We were also reminded to attend the Asian Battery Conference which occurs in alternate years to the European Lead Battery Conference.

The 13th Asian Battery Conference will be held on September 1-4, 2009 in Macau, China.

The European Automotive Battery Market Past, Present and Future

This session was based on a paper by Graeme Fraser-Bell of Entek International and R. David Prengaman of RSR Technologies. After presenting some initial facts and estimates on SLI battery production and usage in Europe, Graeme asked the question, "What threats have emerged to the flooded SLI battery in the European market?" He then described the threats to flooded battery technology which are 1) Mercedes' and BMW's increased use of the AGM battery, 2) CAFÉ (Corporate Average Fuel Economy) legislation for reduced emission of CO2 which will be <120g CO2/km by 2012, and 3) The immediate introduction of and conversion to micro-hybrid (stop/start) vehicle tech- nology.

Beginning with item 1, the advantages of AGM technology are that these batteries offer lighter weight, better cycling per-formance, improved reliability, less chance of foreign competition, multi-use production facilities and better sales margins.

These features outweigh the negatives which are typically related to manufacturing difficulty such as scrap rates, manufacturing costs and the need for new investments. In 2008, production of AGM batteries for SLI applications in Europe almost hit 2MM units, which is about 10% of the OEM SLI battery production.

Items 2 and 3 are very closely related. Because of the CAFÉ requirements in Europe, the automobile manufacturers have all developed plans to convert their fleets to micro-hybrid (stop/start) technology. In 2013, 80% of the EU27 automobile producers will be converted to micro-hybrid technology. By 2015 this number is promised to be 100%. Graeme sees this as a threat and an opportunity for flooded SLI battery production. He stated that there currently is an insufficient capacity to convert all these vehicles to AGM and that the cost of AGM is ~2.5X that of a flood battery. He went on to say that an improved cycle life-flooded battery could meet the OEM duty cycle and cost targets. He even offered some design options for those interested parties, and briefly mentioned mild and full hybrid technology, stating that with the introduction of micro-hybrid technology, these introductions will be slowed.

He concluded by giving us a view of the SLI battery market in the future. He believes that an extended cycle life (ECL) flooded battery must be developed in order to capture a portion of this changing market. His data showed that in 2008, OEM EU27 SLI battery production was divided at 20.4MM flooded units and 1.7MM AGM units. With the introduction of an ECL-flooded SLI battery he predicts the resulting 2013 OEM SLI market distribution will be 8.4MM standard flooded, 7.0MM AGM and 7.0MM ECL flooded.

When Graeme concluded his presentation the audience came alive with many hushed discussions.

Building the Hybrid Electric Vehicle Technical Road Map for the Advanced Lead Acid Battery Consortium

Timothy Ellis of RSR Technologies told a great story about market pull in the development of the HEV technology road map for the ALABC. He began by stating that this collective effort was stimulated in part by the restriction (relative to lead-acid) in various government-sponsored battery development programs for hybrid technology.

The ALABC team began working to determine the objectives, establish the drivers and then set up working groups. These working groups identified the challenges and quantified the requirements, which were then tied back to the CAFÉ requirements. After coming to a consensus, their committee implemented their road map and began to evaluate the innovation necessary. The ALABC funded a of the key issues that were the bane of the lead-acid battery. Issues like premature cycle life (PCL) failures and partial state of charge (PSOC) operation were addressed and corrected. The pulse power limitations of lead-acid were also brought front and center and were suc-cessfully countered. Then several Honda Insight HEVs were converted from nickel metal hydride to these "advanced" lead-acid battery designs to demonstrate the suitability of lead-acid for this demanding application. The success of this program has breathed new life into the lead-acid battery business.

Another issue that is still to be addressed is "system" weight. Though the lead-acid battery does not have the peripheral charging and safety equipment required by a Li-ion battery, the "system" weight is still heavier (though not by much) than the Li-ion battery system. The ALABC road map is now targeting a significant increase in active material utilization in the lead-acid battery, which is currently only ~55% at best under the HEV operating conditions.

We will look forward to Ellis's next report which will most likely address this issue.

An Update on High-speed Continuous Paste-making

Al Vincze of Tech Cominco discussed the company's recent introduction of the concept of continuous paste- making using a twin-screw extruder. This is the same general technology that is used to continuously extrude a mixture of polyethylene, silica and oil that create today's SLI battery separator. The extruder as engineered by Tech Cominco can continuously produce paste at a rate of between 500 and 5,500kg/hr. This system has demonstrated production at up to 400,000 plates in an eight-hour shift.

The Tech Cominco continuous mixer has a through-put (residence time) of ~35 sec and uses state of the art gravimetric feeders to continuously deliver oxide, fibers, expander and acid to the mixer input. The paste morphology can be controlled by mixing speed, barrel loading, paddle angles and injection location for the addition of acid and water. This system offers better control of free-lead, more uniformity, reduced operator oxide exposure, simple cleaning and with no lumps or granules greater than 1.5mm in diameter. Vincze stated that this patented technology is a technological first in the lead-acid battery industry.

Graphite as a Conductive Additive

Based on a paper by Mathis Wissler and F. Henry of Superior Graphite-Europe, this presentation began with some background on the use of high purity graphite in batteries. As it turns out, graphite is used in most batteries with the most predominant market being the primary alkaline battery. In this battery, the graphite is used in the MnO2 cathode to improve the conductivity and material utilization (at levels of ~10:1 by weight which equates to volumetric levels of approximately 1:1).

The electrical conductivity of graphite in a composite system has two main aspects: the intrinsic conductivity and the contact-to-contact resistivity. The contact-to-contact resistivity is influenced by particle size, particle shape and porosity. In this presentation high purity graphite was milled or treated by different methods to produce different particle shapes and sizes. The resulting graphite particles were characterized for particle size, density, BET surface area and electrical resistivity when mixed with MnO2 and pressed into a pellet. The graphite was modified by several techniques including: spherodizing milling, hammer milling, spiral air-jet milling, particle to particle air milling and chemical exfoliation / thermal expansion.

Wissler showed that the electrical resistivity of the pressed pellets did show a strong relationship to particle bulk density and particle size of the graphite but not the BET surface area. He therefore concluded that milling and other related graphite processing can be used to increase the effectiveness of the graphite as it relates to battery performance and life.

'Smart' Battery Separators

How 'smart' can a battery separator actually be? This paper by Jorg Deiters, George Brilmyer and Rick Wimberly of Daramic LLC described ways in which the battery separator could theoretically protect the battery and extend its life. Through the use of pore controlling agents (PCA) these researchers are developing battery separators whose pores open and close in response to changes in the local environment within the battery.

Two typical battery problems were discussed. Hydration shorts, for example, can be formed in the battery separator when a battery is fully discharged and the electrolyte is more like water than like acid. Jorg proposed filling the pore of the separator with small quantities of PCAs that expand in water yet shrink in acid, thus protecting the separator from dendrite formation and shorting.

The second battery problem addressed by the smart separator was thermal runaway in AGM batteries. A smart AGM separator was produced and tested that incorporated PCA's that expanded irreversibly at temperatures above 130 degrees centigrade. The electrical resistance of this separator was shown to increase up to four times when exposed to heat, typical of a battery in thermal runaway. Such a separator would not save the problem battery per se but would protect the other batteries in the string from damage along with the associated equipment. Though not in production today, these "smart separators" or adaptations thereof could prove very useful in the industry.

The UltraBattery -- A New Battery Design for a New Beginning in HEV Energy Storage

According to a paper by Allan Cooper of CSIRO, J. Furukawa of The Furukawa Battery Corp, L. T. Lam of CSIRO and M. Kellaway of Provector Ltd., the CSIRO UltraBattery is a hybrid energy storage device that combines a lead-acid battery with an asymmetric super capacitor. This design takes the best from both technologies and transforms them into one very powerful energy source. What they have actually done here is remove a portion (~1/3) of the conventional prismatic negative plate and replace it with a prismatic high surface area capacitor (carbon) electrode. The capacitor electrode enhances the power of the negative plate as it acts as a buffer during high rate charging and discharging. (The positive plate of the battery can normally handle these power pulses since its available surface charge is typically ten times that of the negative plate.) There are also other benefits that relate to partial state of charge operation and battery life.

Cooper went on to describe the relationship between CSIRO and Furukawa Battery and how a set of twelve 12-Volt modules were constructed for testing. These tests consisted of retro-fitting the UltraBattery battery-pack into a Honda Insight HEV. This vehicle was fitted with all the necessary battery monitoring equipment and then tested at the Millbrook Proving Grounds under a General Motors road test simulation cycle. The test was initially planned to run for a duration of 50,000 miles which was completed in August 2007. After reviewing the parallel laboratory test data and the vehicle test data it was determined that the proving grounds tests should be extended to 100,000 miles. This extended test was successfully completed in January 2008 without incident.

The UltraBattery is now being redesigned for reduced weight. The current battery is 22Kg heavier than the original Honda Insight's Ni-MH battery. The new design will be at least 12Kg lighter than the original UltraBattery. It is an understatement when I say that this development has the lead-acid industry all excited.

Advanced Lead-Acid Batteries in HEV Applications
(Fuel Cell / Battery Lift Trucks)

Kevin Smith of East Penn Manufacturing Co. Ltd. described typical lift truck operation and how productivity is routinely lost due to changing batteries one to two times per day, weekly battery maintenance and motor/relay/contact failures. One approach East Penn is proposing is to couple the lift truck battery with a fuel cell and thereby eliminate the need for changing batteries.

East Penn Mfg. has partnered with Nuvera Fuel Cells to develop a prototype fuel cell / battery hybrid that they are calling "Ready Power". The fuel cell they are working with is a 5kW hydrogen fuel cell with 25kW peak power capabilities. The original lift truck battery was 750 AH / 36 VDC and when coupled with the fuel cell was reduced to 75 AH / 36 VDC. Their system is combined with the Nuvera "Power Tap" unit that reforms (produces) hydrogen from natural gas. Smith reported that through the use of "Ready Power" East Penn has been able to totally eliminate battery changes and the system has been operating for more than 12,000 continuous hours.

Carbon materials for lead acid batteries

The talk by Jean-Yves Huot of Timcal Graphite & Carbon ended the 11ELBC event in Warsaw, Poland on Friday, Sept 26. The first part of his presentation emphasized the presence and the role of carbon materials in various battery chemistries; with the second part dedicated to carbon materials in negative electrodes of lead acid batteries. In the past few years, several groups indeed found that larger addition of carbon materials to the negative electrode decreases electrode sulfation and improves performance under partial-state-of-charge operation.

Huot showed that carbon materials are key components of most modern batteries. He described the carbon materials that are currently used in various battery chemistries such as primary ZnC and alkaline batteries, and rechargeable lithium batteries. He showed that the performance of carbon materials can be predicted from out-of-cell Performance Indicators such as electrical resistivity of dry carbon-active material blends. He presented a few examples of electrode formulations.

The second part of Huot's presentation was devoted to lead acid batteries (LAB). Huot summarized the rationale behind the selection of carbon materials that are being tested in negative electrodes of LABs. Although the mechanism of the carbon effects in the negative electrode remains largely unknown, he presented properties of graphite and carbon black that might impact on the carbon effect in LABs, and the possible role of carbon materials.

Dr. Huot concluded by stating that Battery-grade synthetic graphite and conductive carbon black used in battery chemistries share a common role of conductive additives. The selection of the right carbon family, grade, size distribution and percentage in the negative electrode of LABs is very challenging. On the other hand, the search for the mechanism of the carbon effects could benefit from testing various carbon families and grades, and comparing with other battery chemistries.