File photo: Ratan Tata

Ratan Tata, chairman emeritus of Tata Sons, in his personal capacity has invested in Ampere Vehicles, a start-up co-founded by a woman entrepreneur.Coimbatore-based Ampere makes electric vehicles including e-scooters, e-cycles and e-three wheelers. Hemalatha Annamalai, co-founder of Ampere, told NDTV that the funding would be used to scale up the operations. She also said that Mr Tata made the investment along with Ampere's existing investor Forum Synergies. Spain's Axon Capital is also a co-investor in Ampere.Ms Annamalai told said she started her entrepreneur journey at the age of 27 after quitting a software job. Ampere is her fifth entrepreneurial venture which she co-founded in 2008.Ampere did not disclose how much stake Ratan Tata has picked up in the company or the quantum of his investment.The former Tata Group chief has been steadily investing his personal equity in a number of start-ups, since retirement. Mr Tata has invested in many start-ups including Ola, Snapdeal, Paytm, and Xiaomi.He has also invested in another automobile-related start-up Cardekho.com.Ratan Tata retired as the head of the over $100-billion conglomerate Tata Group in December 2012 and currently serves as chairman emeritus of Tata Sons, the holding company of Tata Group.