AABC Europe 2013 - AABTAM Symposium: Advanced Automotive Battery Technology, Application and Market - Session 2

Energy Storage for Low-Voltage Hybrids

In this session, automakers presented vehicle development and energy-storage requirements for low-voltage hybrids and energy-storage developers discussed their new offerings.

Session Chairman:

Dr. Karden is Technical Expert for Battery & Energy Storage Technology at Ford's Corporate Research and Advanced Engineering Centre in Aachen, Germany. Since he joined Ford, he was responsible for numerous projects in the fields of powertrain electrification, battery modeling and monitoring, and storage technology assessment, with a main focus on micro-hybridization in 14V systems.

1. Flooded Type ISS Battery with Improved High Dynamic Charge Acceptance
   Tetsuro Okoshi, Manager of Battery Design Department, Shin-Kobe Electric Machinery Co., Ltd
   Abstract 

   

   The idling stop vehicle is quickly expanded for the correspondence to increasing fuel consumption regulation. In Japan, full-scale spread started in 2009, and Shin-Kobe launched enhanced flooded type batteries (EFB) for idling stop vehicles in 2010. In order to meet the fuel consumption improvement demand of an idling stop vehicle, technical improvement of EFB has been continued.

   Gen2 has been launched in 2011. Dynamic charge acceptance of Gen2 improved greatly to Gen1. New technologies such as high density active material for positive and new carbon for negative were adopted. The durability characteristic of Gen2 was also been enhanced. Because, the new carbon restrains the negative active material from sulfation and  helps to improve durability under PSOC conditions. It is expected that Gen2 will meet the durability performance demand in the Europe market where high durability is demanded. In order to continue to meet the higher fuel consumption demand, the technical development of dynamic charge acceptance will be continued.

   • Background
     • Japanese market trend of the idling stop vehicle.
     • Shin-Kobe’s experience until year 2012.
     • Further understanding of circumstances under stop and start conditions.
      
   • The Battery concept of Gen2.
     • Comparison of characteristics between Gen1 and 2.
     • Introduction of constituent technologies of Gen2.
     • Evaluation results of performance under PSOC conditions.
      
   • The Battery concept for the future
   • Summary

   Close Abstract
2. Next Generation Lead-Acid Batteries with Improved Charge Acceptance for Advanced µ-Hybrid Applications
   Luca Brisotto, Director Project Management & Advanced Applications, Transportation OE, Exide Technologies Srl
   Abstract 

   

   EXIDE has been actively working on Lead Acid batteries for m-hybrid applications since 2006, and has been a partner of several car manufacturers developing a range of Improved Flooded (EFB) and AGM batteries which are currently equipped on a wide range of vehicles.

   Evolution of micro hybridization systems and experience accumulated in more than 5 years “on the S&S market” have been the main drivers to investigate advanced  solutions in order to better fit the increasing technical demands of the application.

   Specific Power, extended energy throughput and improvement in real life dynamic charge acceptance (DCA) have been a major focus especially in the evolution of EFB technology.

   With particular reference to optimization of Negative electrodes through specific carbon additives, investigation was conducted to understand the impact of DCA improvement on some of the most important application-related battery performances.

   • Roadmap of m-hybrid Lead Acid Batteries evolution
   • EFB Gen IV
     • Power & cycle life improvement
      
   • EFB Evolution
     • Application background
     • Dynamic Charge acceptance improvement
       • Impact on EFB IV+ performances
       • “ECO” design possibility
        
     • Opportunities & targets of EFB Evolution
      
   • Summary & Conclusions

   Close Abstract
3. Advanced Lead Carbon Batteries in the new Low Voltage Micro Hybrids
   Allan Cooper, European Project Coordinator, European Advanced Lead Acid Battery Consortium
   Abstract 

   

   The Advanced Lead Acid Battery Consortium (ALABC) has for several years been demonstrating VRLA batteries in hybrid electric vehicles and has successfully shown that advanced designs with a carbon-containing negative plate can adequately cope with this duty cycle and exhibit good reliability.  This demonstration work has previously been done by retro-fitting existing mild hybrid vehicles, however with the wide acceptance of stop/start in Europe, the industry is looking for ways to increase functionality of these systems to obtain lower emissions to meet future standards, but at minimum extra cost. The effect of engine downsizing coupled with performance boosting by combining electric supercharging and turbocharging has been explored in this programme as this offers a significant reduction in CO₂ without loss of performance at an affordable cost and can operate well with the new generation lead carbon batteries.

   Thus Controlled Power Technologies (CPT) and the ALABC commissioned AVL Schrick to convert a vehicle to the mild hybrid system proposed and the chosen vehicle has been the current model VW 1.4litre TSI ‘Blue Motion’ Passat.

   The paper will cover:

   • The role of carbon as an additive in the negative plate in partial state-of-charge HEV applications.
   • The effect of carbon on dynamic charge acceptance.
   • Bench and vehicle testing of advanced lead carbon battery designs.
   • The development of the 12V version of the LC Super Hybrid and performance results obtained.

   With the very aggressive CO₂ emission standards being set in Europe, the car manufacturers are seeking extra functionality from a relatively low voltage boardnet. This voltage has seemingly been set at a nominal 48V to allow for a top of charge voltage not exceeding 60V – a normally accepted upper limit where additional safety and isolation measures are required.  At this voltage, a much higher level of regenerative power becomes available (8-10 kW) which will allow for such additional functions as direct engine assist and engine switch-off in the cruise (sailing). Many manufacturers are also seeking to move some of the traditional hotel loads to the higher voltage.  In order to explore the possibilities for advanced lead-carbon batteries in this application, the ALABC and its partners in the LC Super Hybrid Project have commissioned AVL Schrick to build a new vehicle to this new standard. Progress on this project will be reviewed.

   Close Abstract
4. Mazda ”i-ELOOP” Brake Energy Regeneration System and Strategy
   Masayoshi Takahashi, Staff Manager in charge of the development of i-ELOOP, Mazda Motor Corporation
   Abstract 

   

   Mazda have improved fuel efficiency substantially based on the Sustainable Zoom-Zoom plan that we announced  Mazda’s long-term vision of technology development  in 2007.

   This approach aims to effectively reduce total CO₂ emissions with cars that offer driving pleasure and excellent environmental and safety performance to all our customers.

   Consequently, MAZDA adopted Building Block Strategy that is prioritizing improvement of the base technologies such as improving the powertrain efficiency that are responsible for the core performance of our cars while gradually introducing electric devices such as regenerative braking, hybrid and other systems.

   As the second step of this approach, Mazda has developed a new regenerative braking system called i-ELOOP that recover electricity from the kinetic energy during deceleration and reuse the electricity for a vehicle to move.

   This system is constituted a variable voltage alternator up to 5kW, a EDLC up to 25V for charging generated electricity and a step-down DCDC convertor for components of 12.8V for recovering more electricity . MAZDA launched i-ELOOP to new mazda6 at the beginning, and will launch it in the other car models.

   In the future,  MAZDA  will continuously improve i-ELOOP that is better fuel efficiency and more reasonable.

   Close Abstract
5. Li-Ion Battery Pack for Micro Hybrid Vehicles: Development and Series Application
   Lawrence Alger, Principal Engineer, EV/HV Engineering, DENSO International Europe
   Abstract 

   

   Road to Sustainable Growth: DENSO believes that global corporations have a responsibility to improving society through their actions. As the leading EHV supplier DENSO is driving forward the development and application of new solutions to achieve the goal of sustainable growth for society.

   Since Micro Hybrid Vehicles (μHV) are now mainstream, and will dominate the EHV market for the foreseeable future, low-cost technological developments that improve fuel economy will take us another step along the road to sustainable growth.

   This presentation explores the development and application of the World’s first mass production 12V Lithium-ion battery fitted to the new Suzuki Wagon R and covers the following topics:

   • Background of the Development
   • Microhybrid System (Idle Stop System)
   • Lithium-ion Battery Pack
   • System Operation
   • Fuel Consumption Improvement
   • Structure / Reliability
   • Series Application in the Suzuki Wagon R
   • Summary

   Close Abstract
6. Comparison of Energy Storage Alternatives for Micro-Hybrids
   Christoph Fehrenbacher, Director, European Application Engineering, A123 Systems
   Abstract 

   

   Energy storage devices in micro hybrids and ICE vehicles are facing significantly increased requirements in upcoming years. Increasingly difficult regulations are a major driver for further fuel economy improvements and as a result, implementation of stop-start features and improved regenerative braking are global objectives. The introduction of new electrical comfort functions will also increase the dynamic loads on the vehicle power net. The multiple energy storage alternatives that are currently under evaluation for the next generation of low voltage hybrids will be discussed and compared.

   • Technical concepts:
     • Single battery systems
       • Lead acid
       • Li-ion
        
     • Dual energy storage systems
       • Lead acid + ultracaps
       • Lead acid + Li-ion
        
     • Dual voltage/dual energy storage systems
       • 12V Lead acid + 48V Li-ion
        
      
   • Comparison of
     • Potential fuel/emissions savings
     • Further benefits
     • System complexity
     • System cost
      

   Close Abstract