BATTERIES & SUPERCAPS POST MORTEM ANALYSIS PLATFORM EXTERNAL SERVICES

Transcription

1 BATTERIES & SUPERCAPS POST MORTEM ANALYSIS PLATFORM EXTERNAL SERVICES

2 CONTEXT Over the last years a remarkable evolution has taken place by the introduction of new batteries & supercapacitors technologies in both traditional and new applications. It s lead to a fast rising number of manufacturers and new suppliers appearing in the market place. At the same time, more than thirty years of R+D in material science have resulted in better batteries and supercapacitors. These outcomes came from a better understanding of mechanism of the materials level. From the demand point of view, more stringent specifications are requested aiming at longer lifetime systems, while at the same time those energy storage devices become complex and expensive. In the context of supply and demand, within a very competitive market, it is essential to count with all possible tools that will allow an optimal integration of these technology providers amongst different end-user applications. The idea is to contribute not only to the added value of the final product, but also to gain competitive advantage to the company. A post-mortem study at material science level provides invaluable information on what type of treatment, quality of control and monitoring the battery and supercapacitor has been subjected during its lifetime. What it s learned will provide very useful information to extract the maximum possible economic advantage from those batteries and supercapacitors. The ageing behaviour depends on a wide range of parameters (e.g. state of charge, depth of discharge, charge/discharge rate, charge variability, and temperature). All those parameters must be studied in depth to better understanding the effects of different environmental conditions during ageing. The mechanisms of electrochemical device ageing can therefore be evaluate and correlate with them applications.

3 REQUIREMENTS FOR ADVANCED BATTERIES AND SUPERCAPS Power density Advanced Batteries Safety Operating Temperature Cycle/Calendar life Energy density Cost EXAMPLE OF ANALYSED SYSTEM Pouch cell Batteries 16.2 Ah, 3.7 V Supercaps F, 2.7V Prismatic battery Batteries 40 Ah, ~3.7 V Supercaps F, 2.7V Cylindrical battery Batteries 2.3 Ah, 3.3 V Supercaps F, 2.7V All-solid-state battery 300 mah, 3.75 V Coin cell < 1 mah, V

4 AGEING MECHANISMS IN LI-ION BATTERIES AND SUPERCAPACITORS AGEING CAUSES ENHANCING FACTORS IMPACT Electrolyte Electrolyte decomposition High T ( C), High C-rate Capacity, Safety Carbon anodes - electrode/electrolyte interface Electrolyte decomposition (Continuous side reaction at low rate) Solvent co-intercalation, gas evolution and subsequent cracking formation in particles Changes in porosity due to volume changes, SEI formation and growth Contact loss of active material particles due to volume changes during cycling High T ( C), High SOC (high voltage) Overcharge High C-rate and High SOC (high voltage), High T( ) High C-rate, High DOD Capacity, Power Capacity Power Capacity Decomposition of binder High SOC (high voltage) and High T ( C) Capacity Current collector corrosion Overdischarge, Low SOC Power Metallic lithium plating and subsequent electrolyte decomposition by metallic Li Binder decomposition Low T ( C), High C-rates Poor cell balance, Geometric misfits Electrolyte and electrode degradation by-product Oxidation conductive particle High T ( C), water trace in electrolyte Power Corrosion current collectors High T ( C), water trace in electrolyte Power Capacity, (Power) Power, Safety Li Metal Oxide - Structural desordering High T ( C), high C-rate Capacity Li Metal Oxide - Interphase transition High C-rate, High T ( C) Capacity Li Metal Oxide Metal dissolution High T ( C) Capacity, Power Electrolyte decomposition High T ( C), High C-rates, Poor cell airtight Power Separator Separator degradation High voltage Capacity Casing/ packaging Corrosion on hard casing High voltage Capacity Gas permeation on soft packaging High T ( C) Capacity Ageing will be different for each single type of battery and for each application

5 DEFINITION Post mortem Analysis is a process involving testing and characterization of battery & supercapacitor components, pre- and post-cycling, aiming to provide unique insight for establishing a correlation between battery / supercapacitor design operating conditions battery degradation. This will allow: * * Battery and supercapacitor companies to improve cell manufacturing processes refining their technology. End-user companies to: SCOPE Establishing a baseline of raw materials, followed by post-mortem analysis of electrodes and electrolytes complement performance testing. SIZE: Test methods are readily applied from button and coin cell to prismatic product. DEPTH: Phase I: basic system knowledge to have a first selection criteria input. * * Select the best technology to be implemented in their systems. Adapt the integration process providing solutions for more efficient Battery Management System (BMS). Better motoring the SOH and SOC of the battery / supercapacitor induced by the ageing and/or operating conditions. Phase II: deeper study involving not only Analytical Testing but also electrode & electrolyte surface characterization as well as current collectors. CIC postmortem-line Battery ageing Assessment Understanding of ageing mechanisms Advanced materials (lab scale) New design

6 PHASE I basic system knowledge to have a first selection criteria input Task 1: Disassembling of electrode-containing devices: include the ante-mortem and post-mortem cells. Task 2 : Physical, chemical and morphological characterization of aged components. Structural characterization to study the effect of ageing on the materials and possible sidereactions Optical characterization of the materials (visual observations) Optical microscopy Adhesion test Electron microscopy (EM) measurements to study changes in the microstructure, particle size, salt deposits, etc Deliverable: REPORT

7 PHASE II deeper study involving not only Analytical Testing but also electrode & electrolyte surface characterization as well as electrode compound (binder, current collector, conducting agent, porosity) and interactions between positive and negative material Task 3: XPS in order to characterize the surface of aged electrodes, separators and SEI Other characterization techniques. ICP-OES to determine the chemical composition/ impurities Raman spectroscopy, IR: e.g. surface groups on carbon Solid state NMR to characterize for example Solid-state lithiumion batteries polymer electrolyte Task 4: Post-tests electrochemical characterization on aged electrodes. Electrochemical tests to study the electrochemical behaviour of each electrode EIS will be used to evaluate the performance of supercapacitors and to study SEI layer, resistance, capacitance and charge transfer of Li-ion batteries electrode OTHER CONDITION OF LITHIUM BATTERY AGEING Analysis of cycle aged batteries at different temperatures, SOC windows and C-rates. TEMPERATURE ºC Copper Anode Current Collector Dissolves Cathode Breakdown Short Circuit LITHIUM ION CELL OPERATING WINDOW Thermal Runaway Death and Law Suits Possible Venting Cathode Active Material Breakdown Oxygen Release and Ignition Exothermic Breakdown of Electrolyte Release of Flammable Gases Pressure and Temperature Increase Separator Melts Breakdown of SEI Layer Temperature Rise Lithium Ion Safety Window Lithium Plating During Charging Capacity Loss Overheating Lithium Plating During Charging No Fires Yet CELL VOLTAGE (V)

8 BENEFITS Diagnostic of aged cells. Complete physico-chemical and morphological and electrochemical analysis including surface analysis (interaction electrode/liquid electrolyte) of the system components. Understandin g of ageing mechanisms for improvement of battery and supercaps materials. Understanding of ageing mechanisms for optimal use of the device. Rigorous protocols of investigation which can be easily reproduced. On the contrary of other centers, the focus of the post-mortem research line will be not only on the study of Li-ion technology for automotive applications but also development post mortem analysis applicable for other technologies such as Li-S or supercapacitors for various applications. TEAM Experienced team with more than five years of deep knowledge on the area. REFERENCES European projects within horizon MAT4BAT (European project 2016) Collaboration with local, national and international partners CEGASA IKERLAN Zentrum für Sonnenenergie- und Wasserstoff- Forschung (ZSW) Argonne National Laboratory CIC Energigune Industrial partners on a confidential basis CONTACT Dr. Emilie Bekaert. Research Line Manager ebekaert@cicenergigune.com Parque Tecnológico C/Albert Einstein, Miñano (Alava) Spain Jose Castellanos. Corporate Development Director jcastellanos@cicenergigune.com Parque Tecnológico C/Albert Einstein, Miñano (Alava) Spain Make a request and our team will contact you for a proposal.