Modern society faces two main energy challeges: moving to electrical propulsion (the EV revolution) and using as much as possible sustainable energy in replacement to fossil fuels. Meeting well these challenges requires development of novel electrochemical power sources and technologies for energy storage and conversion. For EV applications, Li ion batteries are the most suitable power sources. However, the suitable Li ion batteries today for electrochemical propulsion comprise graphite anodes and LiFePO4 or Li[MnNiCo]O2 cathodes. The energy density of these systems is around 100Wh/Kg (for full size EV batteries). This relatively low energy density sets a limit of 100-150 driving distance between charges. Advanced Li ion batteries based on Li-silicon anodes and high capacity cathodes (e.g. Li2MnO3-LiMO2; M=Mn,Ni,Co) can increase the state-of-the-art performance of Li ion batteries by 50%. This meens that EVs propelled by conventional Li ion batteries will be always inferior to ICE cars in terms of driving ranges. Li-S and Li-air batteries, if can be developed as rechargeable and safe systems, can close the energy density gap between Li batteries and ICE. However, Li metal can not be used as an anode for rechargeable batteries. It will be possible to replace it by Li-Si and Li-Si-C composite anodes for these systems. Both sulfur and oxygen cathodes, suffer from intrinsic problems that have to be fully addressed in order to develop practical batteries based on them. In this presentation the challenges in R&d of practical Li-S and Li-air batteries will be discussed.
Key questions: Can sulfur reduction products be re-oxidized back to sulfur? and – Do we have really polarb a-protic solvents that are stable with oxygen reduction products formed in the presence of Li ions?. We will describe our recent work in these areas. We will also discuss possible electrochemical options for load leveling applications. Li ion buttery systems based on Li-Ti-O (spinel) anodes and LiMPO4 cathodes seem suitable. Interesting post Li ion batteries are rechageable Mg batteries. In contrast to Li ion batteries were the performance depends on complicated passivation phenomena and transport properties of surface films, Mg batteries have to operate in passivation free, bare electrodes conditions, due to the nature of the be-valent Mg ions. We had to develop new complex solution chemistry for rechargeable Mg atteries. We can show nice progress with fully reversible Mg anodes in anodically stable complex electrolyte solutions.The challenge remains development of high capacity/ high voltage cathodes. Another interesting challenge is to develop non-aqueous sodium electrochemistry for energy storage and conversion. We see some nice initial progress in this new field. All of these topics will be discussed in this presentation. It will be demonstrated that R&D of novel electrochemical power sources, requires very intensive work on many basic science aspects (surface chemistry, crystallography, spectroscopy, computational chemistry solid state physics and more).
Research Activities :
Advanced electrochemical materials and surface science, Li ion batteries, Metal-Air batteries, Rechargeable magnesium batteries, Improved lead acid batteries , Super capacitors (EDLC), Nano materials for advanced electrochemical devices, Water desalination by electrochemical means, Spectroscopic and nanoscopic measurements of electrochemical systems
Honors and Awards :
- 2005 Awarded the technology award of the battery division of the electrochemical Society (ECS)
- 2010 An associate editor for Electrochemical and Solid State Letters journal (ESL), the journal of Solid State Electrochemistry (JSEL) and the journal of the Electrochemical Society (JES). The chairman of the Israeli Labs Accreditation Authority
- 2011 Landau Prize for green chemistry
- 2012 The excellence prizes of the Israel Vacuum Society
- 2007 and the Israel Chemical Society