Estimation and Fault Diagnostics of Battery PDE Models Scott Moura - PowerPoint PPT Presentation

Estimation and Fault Diagnostics of Battery PDE Models Scott Moura Assistant Professor | eCAL Director University of California, Berkeley Rensselaer Polytechnic Institute (RPI) Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 1

Dong Saehong Eric Laurel Zach Dr. Hector Dr. Chao ZHANG DUNN GIMA PARK MUNSING PEREZ SUN Hongcai ZHOU Sangjae Bertrand Jianchao Luis Ramon ZHANG Zhe BAE TRAVACCA Li CRESPO CUOTO Dylan KATO Mathilde BADOUAL Emily YOU Teng ZENG Prof. Satadru DEY Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 2

Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 3

A Golden Era Keyword Search: Battery Systems and Control No. of Publications 3000 2000 1000 0 1985 1990 1995 2000 2005 2010 2015 Year Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 4

Decline Costs B. Nykvist and M. Nilsson, “Rapidly falling costs of battery packs for electric vehicles,” Nature Climate Change , Mar 2015. DOI: 10.1038/NCLIMATE2564 Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 5

The Battery Problem CHEAP High Energy Fast Long Safe Charge Lifespan & Power Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 6

The Battery Problem Samsung Galaxy Note Boeing 787 Dreamliner Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 6

The Battery Problem Two Solutions Design better batteries Make current batteries better (materials science & chemistry) (estimation and control) Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 6

The Battery Problem Two Solutions Design better batteries Make current batteries better (materials science & chemistry) (estimation and control) Objective: Develop a battery management system that enhances performance and safety. Present BMS* Advanced BMS *BMS: Battery-Management System Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 6

On-Going Research Goals Increase usable energy capacity by 20% Decrease charge times by factor of 5X Increase battery life time by 50% Decrease fault detection time by factor of 10X Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 7

Outline BACKGROUND & PROBLEM STATEMENTS 1 ELECTROCHEMICAL MODEL 2 STATE ESTIMATION 3 FAULT DIAGNOSTICS 4 5 SUMMARY AND OPPORTUNITIES Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 8

History Luigi Galvani, 1737-1798, Experiments on frog legs Physicist, Bologna, Italy “Animal electricity” Dubbed “galvanism” First foray into electrophysiology Alessandro Volta, 1745-1827 Voltaic Pile Monument to Volta in Como Physicist, Como, Italy Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 9

Lithium-ion Batteries Li x C 6 ⇔ C 6 + xLi + + xe − Negative plate rxn: Li 1 − x MO 2 + xLi + + xe − ⇔ LiMO 2 Positive plate rxn: Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 10

Battery Models Equivalent Circuit Model (a) OCV-R Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 11

Battery Models Equivalent Circuit Model (a) OCV-R (b) OCV-R-RC (c) Impedance Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 11

Battery Models Electrochemical Model Equivalent Circuit Model (a) OCV-R - - sep sep + + 0 L 0 L L 0 x (b) OCV-R-RC Cathode Anode Separator c s - ( r ) c s + ( r ) e - Li + e - c ss - c ss + (c) Impedance r r c e ( x ) Li x C 6 Li 1-x MO 2 Electrolyte Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 11

Safely Operate Batteries at their Physical Limits Electrochemical model-based limits of operation ECM-based limits of operation ECM-based limits of operation Terminal Voltage Overpotential Surface concentration Cell Current Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 12

What are we protecting against? Electrolyte Oxidation Cobalt Oxide Electrolyte Stability Potential (E) vs. Li Electrode “Breathing” (Stress/Cracking) Electrolyte Reduction (Kinetically limited) Graphite Lithium Plating (Dendrites) Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 13

What are we protecting against? Electrolyte Oxidation Cobalt Oxide Electrolyte Stability Potential (E) vs. Li Electrode “Breathing” (Stress/Cracking) Electrolyte Reduction (Kinetically limited) Graphite Lithium Plating (Dendrites) Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 14

What are we protecting against? Electrolyte Oxidation Cobalt Oxide Electrolyte Stability Potential (E) vs. Li Electrode “Breathing” (Stress/Cracking) Electrolyte Reduction (Kinetically limited) Graphite Lithium Plating (Dendrites) Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 14

What are we protecting against? Electrolyte Oxidation Cobalt Oxide Electrolyte Stability Potential (E) vs. Li Electrode “Breathing” (Stress/Cracking) Electrolyte Reduction (Kinetically limited) Graphite Lithium Plating (Dendrites) Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 14

What are we protecting against? Electrolyte Oxidation Cobalt Oxide Electrolyte Stability Potential (E) vs. Li Electrode “Breathing” (Stress/Cracking) Electrolyte Reduction (Kinetically limited) Graphite Lithium Plating (Dendrites) Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 14

What are we protecting against? Electrolyte Oxidation Cobalt Oxide Electrolyte Stability Potential (E) vs. Li Electrode “Breathing” (Stress/Cracking) Electrolyte Reduction (Kinetically limited) Graphite Lithium Plating (Dendrites) Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 14

Removing the blinders What we are protecting against What we currently monitor Electrolyte oxidation Temperature Inside every cell / reduction Groups of cells Voltage Lithium Plating (Dendrites) Current Electrode stress/cracking Internal cell defects Thermal runaway Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 15

ElectroChemical Controller (ECC) Measurements I r ( t ) I ( t ) V ( t ), T ( t ) EChem-based Battery Cell Controller + Innovations _ EChem-based Estimated ^ ^ x ( t ), θ ( t ) State/Param States & Params ^ ^ V ( t ), T ( t ) Estimator ElectroChemical Controller (ECC) Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 16

ECC Research Portfolio @ eCAL Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 17

Outline BACKGROUND & PROBLEM STATEMENTS 1 ELECTROCHEMICAL MODEL 2 STATE ESTIMATION 3 FAULT DIAGNOSTICS 4 5 SUMMARY AND OPPORTUNITIES Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 18

Electrochemical Model Equations well, some of them | Open Source Matlab CODE: github.com/scott-moura/fastDFN Equation Description ∂ c ± � s ) · r 2 ∂ c ± � Solid phase Li D ± s ( c ± 1 ∂ ∂ t ( x , r , t ) = s ∂ r ( x , r , t ) s r 2 ∂ r concentration � � 1 − t 0 Electrolyte Li ε e ∂ c e ∂ e ( c e ) ∂ c e i ± D eff ∂ t ( x , t ) = ∂ x ( x , t ) + c e ( x , t ) ∂ x F concentration σ eff , ± ∂φ ± Solid ∂ x ( x , t ) = i ± s e ( x , t ) − I ( t ) potential 2 RT ( 1 − t 0 c ) κ eff ( c e ) d ln f c / a Electrolyte � � κ eff ( c e ) ∂φ e ∂ ln c e ∂ x ( x , t ) = − i e ± ( x , t ) + 1 + ( x , t ) F d ln c e ∂ x potential ∂ i e ± Electrolyte ∂ x ( x , t ) = a ± s Fj n ± ( x , t ) ionic current α aF RT η ± ( x , t ) − e − α cF RT η ± ( x , t ) � Molar flux � j ± n ( x , t ) = 1 F i ± 0 ( x , t ) e btw phases � 0 + dT � T 0 ( t ) − T ( t ) � dt ( t ) = h + I ( t ) V ( t ) − 0 − a s Fj n ( x , t )∆ T ( x , t ) dx ρ c P Temperature Scott Moura | UC Berkeley Battery ID, Fault Diagnostics, & Control March 28, 2018 | Slide 19