Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: LiCoO2

Sortuj według:

Ogranicz wyniki do:

Electronic band structure and migration of lithium ions in LiCoO2

Andriyevsky B., Doll K., Jacob T.

Zeszyty Naukowe Wydziału Elektroniki i Informatyki Politechniki Koszalińskiej

2015

Nr 8

15--24

In view of search the effective materials for the electrochemical sources of energy, the density functional theory (DFT) based approach has been applied to the computational study of lithium ion migration in LiCoO2. Apart the standard first principles study of band structure and density of electronic states of the crystal, the material was studied using the nudget elastic band (NEB) and the ab initio molecular dynamics (AIMD) methods. The activation energy Ea of the lithium ions self-diffusion in LiCoO2, as one of the main characteristic of the material for the electrochemical sources of energy, has been obtained using NEB (0.44 eV) and AIMD (0.5 eV).

Ze względu na poszukiwanie efektywnych materiałów do baterii elektrochemicznych, zostały wykonane obliczenia komputerowe z pierwszych zasad na bazie teorii funkcjonału gęstości (density functional theory) struktury elektronowej oraz migracji jonów litu w krysztale LiCoO2. Oprócz standardowych obliczeń struktury pasmowej i gęstości stanów elektronowych, przeprowadzono także badania materiału metodami NEB (Nudget Elastic Bands) i AIMD (Ab Initio Molecular Dynamics). Otrzymano jeden z głównych parametrów migracji litu w krysztale LiCoO2, stosowanym w bateriach elektrochemicznych - energię aktywacji samodyfuzji Ea. Ta wielkość okazała się być w granicach od 0.44 eV (NEB) do 0.5 eV (AIMD).

Improvement of LiCoO2 cathodes by using Ag2V4O11 as an additive

Cao X., Liu J., Wan J., Xie L., Yan X., Wang H.

Materials Science Poland

2009

Vol. 27, No. 1

287--295

LiCoO2/Ag2V4O11 composites were fabricated as cathode materials for lithium ion batteries by mechanical mixing of commercial LiCoO2 and Ag2V4O11 powders. The underlying principle of this idea was that the metallic silver particles were formed and acted as a conducting matrix when Ag2V4O11 cathode was electrochemically reduced which could significantly increase the electronic conductivity and decrease the polarization of cathode materials. The structure, morphology and electrochemical performance of bare LiCoO2 and LiCoO2/Ag2V4O11 composites were analyzed by XRD, SEM and charge-discharge test of CR2016 coin cells. The results show that a low amount of Ag2V4O11 additive can effectively enhance the discharge capacity and cycleability of LiCoO2. The composite containing 3 wt. % of Ag2V4O11 exhibits a higher discharge capacity and better cycle life than bare LiCoO2.