An elementary 1-dimensional model for a solid state lithium-ion battery with a single ion conductor electrolyte and a lithium metal negative electrode

As noted above, this contribution is dedicated to Norman Fleck on the occasion of his 60th birthday. I have spent many happy hours in collaboration with Norman, and it has been highly productive, educational, rewarding and enjoyable to do so. I look forward to further interactions with him on the subject of this paper, lithium-ion batteries. This work was funded by the University of California, Santa Barbara and by the University of Aberdeen.Peer reviewedPostprin

A Modified Electrochemical Model to Account for Mechanical Effects Due to Lithium Intercalation and External Pressure

For a battery cell, both the porosity of the electrodes/separator and the transport distance of charged species can evolve due to mechanical deformation arising from either lithium intercalation-induced swelling and contraction of the active particles or externally applied mechanical loading. To describe accurately the coupling between mechanical deformation and the cell\u27s electrochemical response, we extend Newman\u27s DualFoil model to allow variable, non-uniform porosities in both electrodes and the separator, which are dynamically updated based on the electrochemical and mechanical states of the battery cell. In addition, the finite deformation theory from continuum mechanics is used to modify the electrochemical transport equations to account for the change of the charged species transport distance. The proposed coupled electrochemomechanical model is tested with a parameterized commercial cell. Our simulation results confirm that mass conservation is satisfied with the new formulation. We further show that mechanical effects have a significant impact on the cell\u27s electrochemical response at high charge/discharge rates

The Photochemical and Thermal Interconversion of Some Cyclopentadienone Dimers

In continuation of previous work on cyclopentadienone dimers [3], thermal and photochemical interconversions of the isomeric diketones 1, 3, and 5 by skeletal rearrangements have been established to the extent summarized in schemes 2 and 3, and the intramolecular [2+2] cycloaddition 1 → 2 was found to be reversible photochemically.</p