** Shares of First Graphene rise as much as 37.5% to A$0.044, posting their biggest intraday percentage gain since April 4, 2024
** Stock hits its highest level since Oct. 28, 2024
** Graphene product maker says it filed a patent for a manufacturing process used to produce graphene-based electrocatalysts for hydrogen generation
** Says modified electrochemical process uses existing capital equipment to create new grades of metal oxide-deposited graphene, leveraging cost-effective base metals
** Notes opportunities for application across global electrocatalyst material market valued at more than $1 bln
** About 763,000 shares change hands, compared with the 30-day average volume of around 570,000
** Stock fell nearly 62% in 2024
(Reporting by Aaditya Govind Rao in Bengaluru)
((Aaditya.govindrao@thomsonreuters.com;))