FRANKFURT, June 21 (Reuters) - Germany"s Varta AG (VAR1.DE) will supply high-performance battery cells to luxury sportscar maker Porsche AG, a spokesperson for the battery maker said. Varta will supply its V4Drive battery cell to the Volkswagen AG (VOWG_p.DE) unit, said the spokesperson, who declined to be more specific. Varta said last month it had won a first customer from the automotive sector, but had not revealed the company"s identity. The news was first reported by Handelsblatt. European carmakers are hoping to cut dependence on Asian cell suppliers as they roll out all-electric models to meet stricter emissions targets in the European Union. Porsche on Sunday said it is setting up a joint venture with Customcells to produce high-performance batteries that will significantly reduce charging times. read more