https://www.reuters.com/article/panasonic-autos-batteries/panasonic-unveils-prototype-battery-to-help-tesla-lower-production-costs-idUSKBN2HF0CV >TOKYO (Reuters) -Panasonic on Monday unveiled a new large prototype battery designed to help Tesla Inc lower electric vehicle (EV) production costs, in a move the Japanese company's battery chief said would deepen business ties with its key U.S. customer.