לוח שנה משולב

The development of high energy density, long running rechargeable batteries like
Li ion batteries, that power so successfully all mobile electronic devices, can be
considered as the greatest success of modern electrochemistry.
However, the basis for this success was the capability of exploring most complex
electrodes, electrolyte solutions and reactive interfaces by most sophisticated
electroanalytical tools in conjunction with advanced spectroscopic and microscopic
was a first-rate leader in electroanalytical ז"ל techniques. Professor Israel Rubinstein
chemistry. I learned a lot from him.
The main theme of this presentation is to examine what is the true horizons for advanced
high energy density batteries that can promote the electro-mobility revolution. The
limiting factor in Li-ion batteries in terms of energy density, cost, potential, durability
and cycling efficiency are the cathode materials used. We will examine most energetic
cathode materials and novel approaches we developed for their stabilization. We
describe in this lecture which electrode materials can be relevant, methodologies
of their stabilization by doping, coating, and affecting electrodes surface chemistry
by the use of active additives. Most important cathode materials are comprising the
5 elements Li,Ni,Co,Mn,O at different stoichiometries that determine voltage and
specific capacities. We will explain how the stoichiometry dictates basic cathodes
properties.1,2 We will discuss the renaissance of Li metal-based rechargeable batteries.3
We have learned how the stabilize Li metal anodes in rechargeable batteries using
reactive electrolyte solutions that induce excellent passivation through controlled
surface reactions. The emphasis is on fluorinated co-solvents that open the door for a
very rich surface chemistry that forms passivating surface films that behave as ideal
solid electrolyte interphase on both anodes and cathodes in advanced secondary Li
batteries. This field provides fascinating examples how systematic basic scientific
work leads to development of most practical devices for energy storage & conversion.

TBD

<p>How do animals make perceptual decisions about incoming sensory stimuli, like touch, smell, and sound, to guide appropriate motor actions? One hypothesis, called abstract coding, is that sensory stimuli activate action-independent "perceptual decision" cells in the cortex, but a decades-long search for such cells has so far yielded mixed results. Another hypothesis, called intentional coding, is that perceptual decisions are made by the same cells that plan the specific action, meaning the coding of perceptual decisions is action-aligned. To distinguish between these hypotheses, we designed a vibrotactile detection task for mice in which they flexibly switched between standard and reversed contingency blocks. While in the standard blocks the mice needed to lick in response to a stimulus, in the reversed blocks they needed to lick in response to the absence of a stimulus. A cortex-wide optogenetic screen revealed that somatosensory and secondary motor cortices are specifically necessary for linking stimulus to action without impairing the ability to lick. However, widefield and two-photon imaging in these and other cortical regions found that differences in activity across perceptual decisions were almost exclusively action-aligned. Our data are thus consistent with the intentional coding hypothesis for vibrotactile detection in mice but do not rule out subcortical abstract coding. At the same time, we discovered a subset of cells in the secondary motor cortex that encoded the block context. Using computational modeling, we demonstrate that this class of cells can align perceptual decision coding to specific motor actions, accounting for both contingency-dependent behavior and the results of optogenetic inhibition seen in our task.</p>

TBD

TBD