The British hydrogen fuel cell company Intelligent Energy (IE) has floated on the London Stock Exchange at a valuation of $1.1 billion. The firm raised $69 million in the Thursday IPO for 8.8 percent of its shares, along with $27 million from Singaporean wealth fund GIC, which now owns around 10 percent of the firm. IE will use the money to sell backup power units for cellular base stations in India, and to support the launch of its Upp personal energy generator (pictured), according to the Financial Times. Early reviews suggest one Upp hydrogen cartridge can charge a mobile device 5 times. IE, which has been developing its technology for 13 years, also plans to make fuel cells for vehicles.