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Natural flake graphite can be modified by controlling oxidation and the intercalation of metal chlorides (Fe, Co, Ni, Cu, Zn) between the carbon layers to produce high quality exfoliated graphite products for shielding and absorption of electromagnetic waves. Low sulphur expandable graphite can be produced by co-intercalation of hydrogen peroxide and sulphuric acid. Other graphites - flexible graphites, exfoliated graphites for heavy oil and organic liquid absorption and sewage treatment, and mild-expanded exfoliated graphites (MEGs) for lithium ion battery anodes - can be prepared by controlling the intercalation/deintercalation reactions. The processes and reactions involved in production of these graphites are discussed and the improvements in properties achieved are summarised., Natural flake graphite can be modified by controlling oxidation and the intercalation of metal chlorides (Fe, Co, Ni, Cu, Zn) between the carbon layers to produce high quality exfoliated graphite products for shielding and absorption of electromagnetic waves. Low sulphur expandable graphite can be produced by co-intercalation of hydrogen peroxide and sulphuric acid. Other graphites - flexible graphites, exfoliated graphites for heavy oil and organic liquid absorption and sewage treatment, and mild-expanded exfoliated graphites (MEGs) for lithium ion battery anodes - can be prepared by controlling the intercalation/deintercalation reactions. The processes and reactions involved in production of these graphites are discussed and the improvements in properties achieved are summarised.

The study involved the examination of the modification of natural graphites to improve their properties for use as anode materials in lithium ion batteries: compatibility with electrolytes, reversible capacity, charge-discharge rate and cycle life. Surface coating of microcrystalline graphite with carbon film and micro-expanding of flake graphite were investigated. A mixture of microcrystalline graphite and phenol resin was carbonised at 1000 degrees C to give a product with a carbon film. In the micro-expansion, which prevents cracks and introduces micropores, sulphuric acid was used to create a graphite intercalation compound of flake graphite that was then de-intercalated to form mild- expansion exfoliated graphite, which was likewise mixed with phenol resin and carbonised. Improved properties compared with unmodified natural graphites were obtained in both cases., The study involved the examination of the modification of natural graphites to improve their properties for use as anode materials in lithium ion batteries: compatibility with electrolytes, reversible capacity, charge-discharge rate and cycle life. Surface coating of microcrystalline graphite with carbon film and micro-expanding of flake graphite were investigated. A mixture of microcrystalline graphite and phenol resin was carbonised at 1000 degrees C to give a product with a carbon film. In the micro-expansion, which prevents cracks and introduces micropores, sulphuric acid was used to create a graphite intercalation compound of flake graphite that was then de-intercalated to form mild- expansion exfoliated graphite, which was likewise mixed with phenol resin and carbonised. Improved properties compared with unmodified natural graphites were obtained in both cases.