Toyota, new electrolyte for all-solid-state Li-ion battery

Toyota has developed a new electrolyte for all-solid-state lithium ion battery. 

The output density of the battery using the new electrolyte is increased to be 5 times that of the previous one. The electrolyte contains expensive germanium. Its practical use requires further development of some other material than germanium.  Refer to here.

All-solid-state lithium ion battery is free from danger of fire and explosion. 

AIST and Toyota cooperatively and already manufactured the prototype of the all-solid state Li-ion battery in 2010. > More

Solar energy technology-5 (artificial photosynthesis)

Artificial photosynthesis based water-splitting hydrogen generation at high efficiency

Water-splitting hydrogen generation technology using solar energy.

A high performance oxide-semiconductor photoelectrode, newly developed, has a multilayered structure.  

A carbonate electrolytic solution of high concentration. 

A multiple of the photoelectrodes are stacked in the electrolytic solution.

The solar energy conversion efficiency achieved is 1.35%, two times of the conventional. March 2012 
More> here.

Solar energy technology-4 (artificial photosynthesis)

Oxygen generation mechanism is elucidated first in the world.

Prof. Nobuo Kamiya, Osaka City University, successfully elucidated exact chemical compositions and atom arrangements of the metal-oxygen cluster in the photosynthesis process of a plant  (April 2012) .  The elucidation of this oxygen generation mechanism is the first in the world. 

The successful study result will accelerate development of the artificial photosynthesis and greatly contribute to the solutions to energy, environment and food issues.  *Osaka City University: http://www.osaka-cu.ac.jp/ja

In the plant’s photosynthesis process, two photosystems operate: a photosystem I (PSI) to reduce carbon dioxide gas and a photosystem II (PSII) to generate oxygen.  It has been said that the oxygen generation reaction is performed in the metal-oxygen clusters of the PSII. 

The overall structure of the PSII is illustrated in Fig. 1.  As illustrated, the PSII is a compound consisting of two monomers.  The PSII receives sunlight and splits water to generate oxygen molecules and at the same time to release electrons. 

The electrons are used to transform carbon dioxide into glucose. 

In the compound structure, the oxygen generation centers are located at two encircled positions.  

Fig. 1 Overall structure of PSII compound

It has been said that PSII oxygen generation reaction progresses in the metal-oxygen cluster in which four manganese atoms (Mn) and one calcium atom (C) are coupled together by a plurality of oxygen atoms (O).  No one has known exact chemical compositions and atom arrangements of the metal-oxygen cluster, however. 

Fig. 2 Chemical structure of oxygen generation center

Purple: Manganese atoms

Yellow: Calcium atom

Red: Oxygen atoms coupling metal atoms together

Orange: Water Oxygen atoms

More> contact us at rvtpe01@hotmail.co.jp

Co-Sponsors:

* Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University

* Strategic International Research Cooperative Program (Finland-Japan), JST

* Academy of Finland

Energy Saving Technology-4 (SiC)

Another All-SiC Inverter was developed by Mitsubishi Electric.

Mitsubishi Electric Corporation developed a prototype forced-air-cooled three-phase 400V output inverter with all-silicon carbide (SiC) power modules that has a power density of 50kVA per liter.  The inverter is expected to contribute to smaller and lighter power-electronics equipment in automotive and industrial applications, among others.

To increase power density, … .  To achieve high current density, … .

More> http://p.tl/CXgW

Energy Saving Technology-3 (SiC)

All SiC Inverter of 0.5 liters volume successfully drives a 15 kW 3-phase motor.

All SiC Inverter:

* Volume: 500 cm3 (0.5 liters) = 1/10 to 1/20 of Si-IGBT inverter commercially available

* Output power density: 30 kW/liter (30 W/cc) (= power conversion value of the inverter for each volume)

* Cooling type: full air-forced cooling

* Power conversion efficiency of the inverter is about 99%. 

* Inverter continuously drives a motor of 15 kW output.

One of the key features of SiC is that SiC is operable at high temperature of 200 degrees of C.  The feature results in significant size reduction of the SiC incorporated inverter.  September 2011, NEDO, FUPET

More>  rvtpe01@hotmail.co.jp

Solar energy technology-3 (artificial photosynthesis)

An artificial photosynthesis system, developed anew, is capable of storing chemical energy of which the amount is in excess of an amount of the energy generated through the photosynthesis of a plant. The artificial photosynthesis system enables itself to synthesize organic materials by using solar energy.
1) Molecules of the material, which are capable of storing high energy of light at low temperature (originally developed), are fixed in and at nano-holes of a unique material.
2) Molecules of the material, which is originally developed in 1) above, together with the molecules, which are easy to react with oxygen, are fixed in and at the nano-holes of the unique material referred to 1) above. It is confirmed that chemical reaction is performed at high efficiency by using solar energy. Osaka University, Prof. Fukusumi, April 2012. More > rvtpe01@hotmail.co.jp

Energy Saving Technology-2 (SiC)

A unique structure of a defect of the SiC crystal, called a screw dislocation, has been shown through the evaluation of the structure of the screw dislocation, which is made by using LACBED (large-angle convergent-beam electron diffraction). 

As known, the SiC-based power device is one of the next generation power devices.

The screw dislocation is known as one of the defects that the SiC crystal has. 

An inverter including the SiC power device having such a defect inevitably suffers from degradation of its performance. 

It has been recognized that the direction in which the screw dislocation extends is the same as of the displacement of the crystal. 

The screw dislocation extends within and through the crystal. 

It has been indicated that the screw dislocation is a unique dislocation in that it contains a displacement having the direction (axis “a”) vertical to the axis “c” along which the defect extends, in addition to the axis “c”. 

Such a defect has been inexplicitly been explained, however.  September, 2012, JFCC, TOYOTA, and TOYOTA Central R&D Labs

To learn more, feel free to contact us at rvtpe01@hotmail.co.jp