Multiscale Hierarchical Modelling, Design, Optimization and Prototyping of Electric Vehicles and Battery Thermal Management Systems

Concept liquid-cooled battery module
Concept liquid-cooled battery module

Motivation. Despite significant advances in energy density, sustained power, charging rates and cost, current lithium-ion battery (LIB) technology still lags behind user expectations, feeding concerns over driving range, charging speeds, battery lifetime, and economics. The next battery technology leap relies on novel thermal management strategies and packaging architectures, realized as intelligent battery thermal management systems (BTMS), which can optimally control the thermo-electro-chemical phenomena occurring inside the batteries to maximize performance, minimize degradation, enable fast-charging protocols, and permit a seamless transition of degraded EV batteries into less-demanding second-life stationary systems.

Multiscale hierarchical framework for thermo-electro-chemical co-design of batteries and electric vehicles

Research Activities. ATOMS Laboratory is developing the next generation of intelligent BTMS to overcome multiple cooling and heating challenges at different levels in the vehicle, from individual components (battery cells, transistors, transformers, and inductors), to sub-systems (battery pack, on-board charger, inverter, electric motor, and cabin), to system-level (vehicle). This work involves concurrent design methodologies and multiscale hierarchical models to revolutionize the electro-thermal design and optimization of thermal management systems for batteries and electric vehicles. In collaboration with UTEV Research Centre and leading industry partners, we are also leveraging our multidisciplinary expertise in EV technologies, multiscale modelling methodologies and state-of-the-art battery testing facilities to design, prototype and test breakthrough packaging and thermal management solutions for pouch and cylindrical battery systems and electric vehicles.  

Thermo-Electro-Chemical Characterization, Performance and Degradation of Lithium-ion Batteries

Motivation. Batteries are complex systems governed by multiscale physical phenomena across thermal, electrical and chemical domains. Although batteries are essentially electro-chemical devices, thermal considerations are of paramount importance because the multiple chemical reactions and ion diffusion/intercalation processes occurring inside batteries are non-linearly modulated by the operating temperature, substantially impacting their performance, degradation and lifetime.

Lithium-ion Batteries

Research Activities. ATOMS Laboratory is developing innovative thermo-electro-chemical characterization methodologies for batteries under a wide range of operating and environmental conditions, including extremely cold weather. We are post-processing battery performance data with numerical methods that enable the estimation of directional thermal conductivities and spatially-dependent heat generation profiles. We are also using Electrochemical Impedance Spectroscopy (EIS) data to detect specific signatures in impedance signals to accurately isolate different contributions to the internal heat generation. These characterization activities inform the development of multi-physics hierarchical modelling methodologies for battery cells, modules and packs, which are crucial to support the design and optimization of thermal management and degradation management systems for batteries.

Electro-thermal Co-Design Methodologies of Power Converter Systems for Electric Vehicle Chargers

Thermofluids of magnetic components
Thermofluids of magnetic components and PCB for an on-board AC Level 2 Charger

Motivation. Adopting faster charging rates is crucial to reduce range anxiety and make EVs more competitive with gasoline vehicles. Today’s power converter systems for EV charging and subsequent power electronic components are required to reliably operate at unprecedented power levels, which has created new engineering challenges for the electro-thermal co-design of these systems. Despite significant advances in recent years, current EV charging rates are still very conservative; the industry requires adopting extreme fast charging rates above 350 kW, which imposes significant thermal constraints on power electronics and magnetic components.

Multiscale hierarchical framework for thermo-electro-chemical co-design of EV power electronics

Research Activities. ATOMS Laboratory is designing and prototyping innovative cooling and packaging architectures for metal oxide silicon field-effect transistors (MOSFETs), insulated-gate bipolar transistors (IGBTs), and power magnetic components for on-board (AC – Level 2) and off-board (DC – Level 3) charging systems. We address the tightly coupled electro-thermal constraints of these novel charging systems within a virtual design environment that concurrently integrates inputs from multidisciplinary fields by coupling CAD generation, electrical architecture design, multiscale thermal analysis, and multi-objective optimization from the device level to system level.

High-frequency inductor-transformer assembly for a DC Level 3 charger
Thermofluids simulation
Thermofluids simulation of an inductor-transformer assembly

Thermal Management Systems (TMS) Laboratory

ATOMS Laboratory is building an experimental facility dedicated to thermal management systems for electric vehicles and charging infrastructure, expected to be operational by Summer 2021. This lab will enable a comprehensive experimental program for thermo-electro-chemical research of batteries. This program, combined with our multi-physics, multiscale methodologies for numerical simulation and optimization, will spur design innovations for batteries and fast-chargers for EVs and second-life battery applications. This lab rests upon three pillars that synergistically rely on the same equipment to investigate battery performance and degradation: (i) thermo-electro-chemical characterization of battery cells, modules and packs, (ii) thermally-safe fast charging technologies, and (iii) thermally-enabled battery life extension.

This experimental facility will foster impactful collaborations with academic researchers and leading industry partners in the automotive, battery technology and charging infrastructure sectors, enabling industry-relevant multidisciplinary training of highly sought-after e-mobility experts and foster new ventures aimed at tapping into the market for vehicle electrification.