Fast-Recharge, high energy density hybrid supercapacitors using sol-gel transformation block copolymer templates

2014 Fiscal Year Research-status Report

• Project/Area Number: 26600072
• Research Institution: Kyoto University
• Principal Investigator: SIVANIAH Easan 京都大学, 物質-細胞統合システム拠点, 准教授 (10711658)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: Battery / Supercapacitor / Testing Facility / Preparation

Outline of Annual Research Achievements

We have established a controlled environment facility for low-humidity preparation of electrode materials - a glove box. We have also established a fabrication facility for preparing battery and supercapacitor button cells. Finally we have established a testing unit facility for battery and supercapacitors button cells.

We attempted to prepare high capacitance electrode materials on the basis of the Collective Osmotic Shock technology and through the use of material transformation techiques. In other words the COS structures were replaced with a oxide material using sol-gel chemistry.

Although this was successful, the principle issue was that the final thickness of the electrode material was not sufficient to detect a strong capacitance result over the noise in the system. Therefore although the principle of our proposal is still correct, we have to adjust the material and device dimensions to get a better performance. We plan to do so in the next year of this project.

Current Status of Research Progress

3: Progress in research has been slightly delayed.

Reason

We made significant progress in building the infrastructure required for an energy storage research group. However since our laboratory began in 2013, there was some delays to get the appropriate infrastructure in place. This is now acheived but it delayed progress in delivering experimental results. We had expected to have completed our electrode materials preparation by now and in this second year, we expected to move to multi-cell preparation. However there were some difficulties in preparing electrode materials with sufficient thickness to gain a large signal-noise ratio.

A significant break-through for us was to find self-assembly block copolymer materials from a commercial supplier at much lower costs, which will enable us to work with large samples. We believe we will overcome such difficulties in the 2nd year since we are now able to access the same base materials at significantly lower costs, which makes it simpler to generate 100micron film samples suitable for electrode preparation.

Strategy for Future Research Activity

We will be preparing single-cell battery units within the next year's activities on the basis of our latest materials. In addition we hope to make partnerships and internships relations with industry that will allow us to learn the cutting edge aspects of battery and supercapacitor storage technologies. We will try to return to our original time-table as best as possible. However our first goal is to deliver a high performance from a single hybrid supercapacitor cell as soon as possible. In order to do so we will be using the following new materials from Horiba-Stec:

In addition to our original block copolymer materials, which are designed to produce a carbonaceous skeletal scaffold for charge storage, we will also use Si containing block copolymers. These can be reduced thermally to a silicon oxide scaffold which can be used a further precursor for generating a nanoporous silicon support. Such support electrodes are expected to significantly expand the capacity for charge storage. We believe that such strategies, along with our original timetable and using our originally proposed materials, will enhance our ability to return to our proposed objective for this proposal.

Causes of Carryover

Due to the delays to develop the electrode material this year, the costs of such materials are being applied to the next financial year.

Expenditure Plan for Carryover Budget

We will purchase block copolymers from a new cheaper source, Horiba-STEC, which provides the base materials for 100 time less cost than our original supplier.

This will allow us to prepare electrode materials that are 100 times thicker than the original proposed materials, and we therefore hope for a better performance from the material.