By Nick Gilbert
Research and Markets has included a new report titled ‘Li-ion Secondary Battery Patent Analysis: Si-based High Capacity Anode Materials’ to its catalogue.
According to the report, silicon-based high capacity anode materials are gaining increasing attention as next-generation anode materials. Graphite is representing over 97% of anode materials for lithium ion secondary batteries irrespective of natural or synthetic graphite. In recent times, the percentage of natural graphite as an anode material is rising. Price of natural graphite is relatively low.
The lingering 3% is represented by high performance anode materials, which give priority concern over performance properties such as charging characteristics although their cost is more than that of graphite anode materials. The market for high performance anode materials has grown by nearly 1%, although it is immaterial. Moreover, these materials are anticipated to replace present graphite anode materials, thus leading to a market with great potential.
These high performance anode materials comprise soft and hard carbon, which are carbon-based materials like LTO-based anode materials, Sn-based anode materials, Si-based anode materials and graphite but without the multi-layer crystal structure of graphite. Among them, silicon or lithium metal demonstrates a theoretical capacity of over 3000 mAh/g, which is a 10-fold increase when compared to 370 mAh/g of graphite. Nevertheless, these metal anode active materials cannot be utilized alone because of their volume expansion of hundreds %. Hence, research is going on to explore techniques of combining with carbon, alloying or nanoizing these materials to reduce anode disintegration because of volume expansion.
This report gives special focus to silicon-based materials as high capacity anode materials and analyzes patents filed between January 1, 1990 and May 31, 2012 in detail. The report studies a total of 1,144 patents filed in the US, Europe, Japan and Korea. Silicon-based anode materials are categorized into monomaterials utilizing only silicon, composites, silicon thin film, which are segmented further.