Subscribe to DeepL Pro to translate larger documents. Visit www.DeepL.com/pro for more information. Battery aging-Battery models-Battery diagnostics-Battery pack design- Electromobility-Stationary energy storage-Energy system analysis. Aging mechanisms of lithium-ion batteries Electrotechnical colloquium at the TU Paderborn 09.04.2019 [lo git Kai-Philipp Kairies, Dirk Uwe Sauer ec h. co m] Chair of Electrochemical Energy Conversion storage system technology d n a 1 Powerful battery storage is becoming increasingly important ...and thus a good understanding of their aging mechanisms ~25 € Battery costs > 25.000 € [te sl a. co m] 2 years Lifetime target 10 years 2 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Powerful battery storage is becoming increasingly important ...and thus a good understanding of their aging mechanisms [T he - P [ti os m till e. on co .c m] o m] Without knowledge of the aging processes, the following questions cannot be answered: Warranty? Leasing rates? Operating limits? Safety limits? Probabilities of failure? Operating strategy? Max. charging currents? 3 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Outline 1 Motivation 2 Structureandoperation oflithium-ion batteries 3 Battery storage aging 4 Calendrical aging 5 Cyclic aging 6 Aging determination in the field 7 Summary 4 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Lithium-ion batteries Large number of material combinations - one operating principle Negative electrodePositive electrode Materials: Materials: Graphite LiCoO2 Graphite & LiMn2O Silicon Li4Ti5O12 4 LiFePO Store 4 Li(Ni0.8Co0.15Al0.05)O2 Li(NixMnyCo1-x-y)O2 .... Unloadin g Separator 5 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Microscopic structure of a lithium-ion battery M. Ender. "Microstructural characterization, model development and simulation of porous electrodes for lithium ion cells." PhD thesis. KIT, 2014 6 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Model: reactions shown vEolnl tglaedlaudnegn M. Ender. "Microstructural characterization, model development and simulation of porous electrodes for lithium ion cells." PhD thesis. KIT, 2014 7 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Outline 1 Motivation 2 Structureandoperation oflithium-ion batteries 3 Battery storage aging 4 Calendrical aging 5 Cyclic aging 6 Aging determination in the field 7 Summary 8 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? Aging 9 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? Aging Hugh Laurie ~90s 10 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? Aging ~90s Hugh Laurie 11 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? H u g h L a u r i e ~ 2 0 1 5 12 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? More beard Aging ~90s Hugh Laurie 13 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? H u g h L a u r i e ~ 2 0 1 5 14 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? More beard Aging Fancier outfit ~90s Hugh Laurie 15 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? H u g h L a u r i e ~ 2 0 1 5 16 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? Aging 17 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? Aging 18 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? Capacity reduction Aging 19 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? Capacity reduction Aging Increase of the internal resistance 20 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology What does "aging" actually mean? Capacity reduction Aging Increase of the internal resistance 21 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology External aging vs. internal aging External aging factors Internal aging factors "What factors influence aging?" "What's happening in the battery?" Keywords: ■ Charging Keywords: current ■ Lithium plating ■ Voltage ■ Solid Electrolyte Interface position (SEI) ■ Depth of ■ Corrosion effects discharge ■ Decomposition of the ■ Temperature electrolyte ■ ... ■ ... 22 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology External aging factors ■ Calendrical aging □ Limits the life of a battery without load. □ Among other things, depending on the duration of storage. ■ Cyclic aging □ Additional aging due to electrical use of the battery. □ Is always superimposed by calendar aging. □ Depending on the energy throughput, among other things. ■ The superposition of calendrical and cyclic aging is nontrivial and an ongoing research topic. 23 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Outline 1 Motivation 2 Structureandoperation oflithium-ion batteries 3 Battery storage aging 4 Calendrical aging 5 Cyclic aging 6 Aging determination in the field 7 Summary 24 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Calendrical aging Significance of the state of charge Calendar aging at 35 °C 102 100 98 R SOC: el 100% at 96 80% iv 65% 94 □ Pouch cell: 20 Ah 50% e 35% ca □ Energy density: 174 20% p 92 □ Wh/kg Cathode: NMC (4:4:2) ac □ Anode: Graphite it 90 y [ei gb in 88 att er % y. co 86 m] 02004006008001000 Storage time in days SOC: State of Charge 25 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Calendrical aging Significance of the state of charge 2.1 2.05 Test temperature 50 °C 2 1.95 C 1.9 ap] h A [t How long does it take for a battery cell to ac e t 1.85 zi loses 15% of its capacity? a ityp a K (depending on their state of charge) [A 1.8 h] 1.75 1.7 1.65 1.6 0100200300400500600700 Test duration Test duration [days] [days] 26 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Calendrical aging Significance of the state of charge 2.1 1200 2.05 Test temperature 50 Test temperature 50 °C °C 2 1000 1.95 C 1.9 800 1.8 Ah Restkapacity T ap] h A [t es st e T ac e t 1.85 zi tm i 600 a ityp a K du e g a [A 1.8 rat T h] 1.75 io 400 n 1.7 [d 200 1.65 ay s] 1.6 0 0100200300400500600700 020406080100 Test duration SOC [%] [days] Test duration [days] State of charge [%] 27 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Calendrical aging Importance of temperature 1 ■ An increase in temperature by 10 K 0.95 doubles the aging rate of electrochemical components Ca 0.9 ct/ ■ Nominal temperature C 0.85 typically 20...25°C, B 50% SOC CV 25°C lifetime warranties only O 50% SOC CV 40°C apply in narrow 0.8 T 50% SOC CV 50°C 50% SOC CV 60°C temperature range 0.75 [a] 0100200300400500 t/days 28 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Calendrical aging In everyday life Practice question How should we charge our smartphones? 29 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Outline 1 Motivation 2 Structureandoperation oflithium-ion batteries 3 Battery storage aging 4 Calendrical aging 5 Cyclic aging 6 Aging determination in the field 7 Summary 30 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Cyclic aging Significance DOD = 100% SOC: State of Charge of cycle depth [1 equivalent full cycles] DOD: Depth of Discharge 100% SOC 0% SOC 100% SOC 31 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Cyclic aging Significance DOD = 50% SOC: State of Charge of cycle depth [0.5 equivalent full cycles] DOD: Depth of Discharge 100% SOC 50% SOC 100% SOC 32 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Cyclic aging Significance DOD = 20% SOC: State of Charge of cycle depth [0.2 equivalent full cycles] DOD: Depth of Discharge 100% SOC 50% SOC 100% SOC 33 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Cyclic aging Significance DOD = 20% SOC: State of Charge of cycle depth [0.2 equivalent full cycles] DOD: Depth of Discharge 60% SOC 40% SOC 60% SOC 34 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Cyclic aging SOC: State of Charge Meaning of the cycle DOD: Depth of Discharge depth No cycling (for reference) 2.2 2 1.8 1.6 C]h 1.4 5% DOD SOC = 50 %, T = 35 °C apA [t SOC = 100 %, ØSOC = 50 % Lad/Ela = 1C/1C ac e t 1.2 zi SOC = 50 %, ØSOC = 50 % Lad/Ela = 1C/1C itya p SOC = 20 %, ØSOC = 50 % Lad/Ela = 1C/1C a [A K 1 SOC = 10 %, ØSOC = 50 % Lad/Ela = 1C/1C h] SOC = 5 %, ØSOC = 50 % Lad/Ela = 1C/1C 0.8 0.6 100% DOD 0.4 0.2 020040060080010001200 Test duration 35 | 09.04.2019Kai- [days] PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Cyclic aging Test duration [days] (proportional to equivalent full cycles)SOC: State of Charge 36 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Cyclic aging Meaning of the SOC window used ■ The area of cycling has a high influence on battery aging (among other things because of phase transitions in the battery) ■ This effect can (but does not have to) be opposite to the calendrical aging 37 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Calendrical aging In everyday life Practice question How do we ensure a service life of 10 years? 38 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology Same cells under same operating conditions age differently Over 25% spread 80% CN □ Sanyo/Panasonic UR18650E □ 1.85 Ah Nominal capacity □ Graphite / NMC □ Cyclization between 3.9 V and 3.5 V □ Current 4.1 A (~2 C) □ 48 cells operated in the same way 39 | 09.04.2019Kai- PhilippKairies Chair of Electrochemical Energy Conversion and Storage System Technology
Enter the password to open this PDF file:
-
-
-
-
-
-
-
-
-
-
-
-