Revealing the thermodynamic background of the memory effect in phase separating cathode materials

Zelič, Klemen (author), Mele, Igor (author), Pačnik, Ivo (author), Moškon, Jože (author), Gaberšček, Miran (author), Katrašnik, Tomaž (author)

Phase separating Li-ion battery cell cathode materials feature a well-known phenomenon called the memory effect. It manifests itself as an abnormal change in working voltage being dependent on cell cycling history. It was only recently that plausible mechanistic reasoning of the memory effect in Li-ion batteries was proposed. However, the existing literature does still not consistently reveal a phenomenological background for the onset or absence of the memory effect. This paper provides strong experimental and theoretical evidence of the memory effect in phase separating Li-ion battery cathode materials. Specifically, the background leading to the onset or absence of the memory effect and the underlying causal chain of phenomena from the collective particle-by-particle intra-electrode phenomena to macroscopic voltage output of the battery are presented and discussed. The results, clearly reveal that no memory effect is observed and predicted for low cut off voltages, whereas the absence of the first rest in memory writing cycle does not result in the absence of the memory effect, as previously believed. In addition, excellent agreement between the simulated and measured results is shown which, on one hand confirms the credibility of the combined analyses and, on the other, provides clear causal relations from macroscopic experimental parameters to simulated phenomena on the particle level.

• Language: English
• Keywords: Li-ion battery, phase separating material, multi-particle porous electrode, memory effect
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2019
• Number of pages: Str. 690-700
• Numbering: Vol. 65, no. 11/12
• PID: 20.500.12556/RUL-113740
• UDC: 621.352(045)
• ISSN on article: 0039-2480
• DOI: 10.5545/sv-jme.2019.6366
• COBISS.SI-ID: 16934939
• Publication date in RUL: 30.01.2020

Record is a part of a journal

• Title: Strojniški vestnik
• Shortened title: Stroj. vestn.
• Publisher: Zveza strojnih inženirjev in tehnikov Slovenije [etc.], = Association of Mechanical Engineers and Technicians of Slovenia [etc.
• ISSN: 0039-2480
• COBISS.SI-ID: 762116

Secondary language

• Language: Slovenian
• Title: Termodinamsko ozadje spominskega efekta v katodnih materialih s fazno separacijo
• Keywords: litij ionske baterije, spominski efekt, katodni material s fazno separacijo, večdelčna porozna elektroda