Session 4: Battery Pack Components and Integration for Electrified Vehicles
Electrical management is crucial to ensure the reliability and safety of automotive batteries in the field. In this session, developers of battery-management electronics and pack integration hardware will discuss requirements, challenges, and solutions for a cost-effective integration of energy-storage packs into electrified vehicles.
Session Chairman: Michael Keller, Leader Energy Storage, Volkswagen AG
Since 2010 Mr. Keller has been leading the energy-storage development group at Volkswagen AG. Between 2005 and 2010 he led the Battery Systems development department at Continental Temic, receiving the “Ferdinand Porsche” Prize in Mary 2009 in recognition of the development of the first application of a lithium-ion battery to high-volume vehicle. Mr. Keller studied Electrical Engineering (Automation) in Karlsruhe, Germany. He started his professional career in 1996 as a Development Engineer at a German industry supplier for power electronics and electric motor products before moving to the hybrid system group of Continental Temic.
SESSION AGENDA
Functional Architecture of Modular High-Voltage Batteries Michael Keller, Lead Energy Storage, Volkswagen AG
Abstract
The development of electric vehicles involves high challenges because of the short development time, the high degree of innovation and the increasing number of vehicle projects. To face these challenges modular concepts have significant advantages relating to development costs and time. The intention of the modularization is to divide a system in standardized functional subunits. This allows the usage of these modules in different projects with significantly reduced amount of development and testing. In classical approach of the development the system is optimized for a single project but this approach of development is not useful for parallel development of different vehicles. The modularization of requirements leads to cell modules with a standardized number of cells and the module Cell Management Controller (CMC). The high voltage contactor and the fuse are combined in the Battery Junction Box (BJB). The control of the high voltage battery takes place in the Battery Management Controller (BMC). The numerous functions of the BMC can be modularized on software and functional level equal to the hardware modularization. Single functional software modules with standardized interfaces can be used in different vehicle projects. This approach has additional advantages compared to the requirements engineering for example the automatic and error-cleaned knowledge transfer to new projects or new suppliers.
Modular strategy of automobiles
System architecture of High voltage Batterie Systems
Modulare BMS architecture
Modular HW components
Modulare BMC Software architecture
Conclution
Close Abstract
Thermal Management of Li-Ion-Batteries – System Requirements, Concepts and Optimized Component Solutions Christian Pankiewitz, Senior Manager System Development, SB LiMotive
Abstract
Thermal Management of Li-Ion-Batteries – System Requirements, Concepts and Optimized Component Solutions Thermal management is one essential function to guarantee lifetime and availability of Li-ion battery systems in automotive applications. This article will
explain the motivation and requirements for battery thermal management in different applications,
introduce fundamental concepts and show their integration into the vehicle,
derive key performance indicators (KPIs) based on the main functions and characteristics of the tempering system,
use the KPIs to evaluate the suitability of different thermal management concepts dependent on the specific requirements of the applications,
explore trends for thermal management driven by advances in battery technology,
look on requirements and concepts for optimizing thermal components of the battery.
Close Abstract
A Comparison of Lithium-Ion Cell Cooling Methods John Burgers, Advanced Product Technology Manager, Dana
Abstract
Choosing between Air and Glycol as working fluids to cool Lithium Batteries and deciding which surfaces to cool is a matter of current and ongoing development in Automotive traction batteries. The presentation illustrates how analytical thermal models can be generated which are computationally efficient compared to finite volume or finite difference methods and offer greater insight into three screening criteria of temperature uniformity, maximum temperature rise and the thermal time constant. Battery designers and automotive thermal engineers are presented with a comparison insight into two popular means of battery cell cooling each operable with air or glycol on a representative battery cell.
Close Abstract
Affordable Batteries for Future xEVs Uwe Wiedemann, Product Manager, Global Competence Team, AVL List GmbH
Abstract
Smart Module and Pack Design for…
… Safety:
improved structural integrity
optimized thermal management
IPxx protection and service security
cell venting system
… Cost:
Mass production oriented production methods and materials
optimized design, i.e. reduced part count, integration of additional functions to components, self locating
minimal numbers of fasteners; same size, same tool, same orientation
… Manufacturability
design for automation, i.e. ease of assembly
optimized sub-assembly process
… Reliability:
BMS control strategy and thermal management
cell fixation, clamping, swelling compensation engineered for individual cell requirements
joint integrity
… Recyclability:
ease of disassembly
use of single and easy to recycle materials
Close Abstract
Simulation and Virtual Product Development of Batteries Sandeep Sovani, Manager, Global Automotive Strategy, Ansys, Inc.
Abstract
An EV/HEV battery is a very different product from those that automotive companies and suppliers are familiar with, and therefore, unusually challenging to develop. There are three major differences
Multiphysics – The variety of different physical phenomena occurring inside a battery and affecting its performance, is far greater than that for traditional auto components. Just to name a few, the prominent physical phenomena in a battery are – electrochemistry, fluid flow, heat transfer, electric fields, structural stresses, plastic deformations, electromagnetic fields, etc. Moreover, all these physical phenomena are tightly coupled and interdependent.
Multidomain – The battery is a distinctly multi-domain product, with key physical phenomena happening in multiple, tightly interconnected domains ranging from the molecular material level, to electrode level, to cell level, to module level, to pack level and to the entire powertrain level. Unlike other auto parts and systems, the unique peculiarity of a battery is that these phenomena are unusually tightly interconnected in a battery.
Multifold – Battery technology is still in a state of great flux. There is very little prior knowledge on large format batteries and, therefore, almost every aspect of the battery is a variable including fairly basic aspects such as electrode materials, cell shape and pack architecture. As a result battery designers have to deal with a multifold of options in deciding each aspect of the battery, with scant prior knowledge to guide them.
Simulation and virtual product development has long been used in automotive product design, but since batteries are drastically different from traditional auto parts, old simulation methods do not readily apply to batteries and simulation methods that follow new paradigms need to be used. To handle the three distinctive aspects of batteries listed above, first, the simulation software needs to have high-end multiphysics simulation capability, with advanced solvers such as fluid flow solver, structural mechanics solver, electromagnetic solver, etc. Secondly, the software also needs to provide the ability to simulate multiple physical domains in simultaneous co-simulation – for instance, solving electrode level electrochemistry in conjunction with cell and module level heat transfer – or provide efficient ways to extract reduced order models of one domain that can be seamlessly integrated into the simulation of higher level domains. Thirdly, through automation the software needs to provide the ability for extensive automated design exploration, so that numerous different design variables and options can be extensively tested.
The current talk mainly presents several battery simulation case studies to illustrate these new simulation paradigms.
Close Abstract
Battery Management Electronics to Meet Automotive Requirements Bob Shoemaker, Systems Engineering Manager, Texas Instruments, Inc.
Abstract
Design Goals for Automotive Battery Management Systems (BMS)
Safety
Reliability
Requirements for Electronic Components
Cost Tradeoffs
ISO26262 Considerations
ASIL requirements
ASIL level directly impacts costs
Example(s)
BMS Performance Criteria
Measurement accuracy
Samples per Second
Communications to Host
Active or Passive Cell Balancing Choices
Battery Management System IC Selection
Assumptions
Number of channels per IC? 6-8-12-16
Cost per channel
Comparing IC's with built-in secondary protectors vs 2 IC approach
