There are lots of claims going around, but the physics just isn't there. Battery storage density isn't high enough currently (and doesn't look to be close) to support large planes. It's the same problem as with 18 wheelers. The larger the vehicle, the battery size increases superlinearly, not linearly. Because adding in battery storage increases the weight required to carry the vehicle, thus increasing the battery storage needs, thus ... and so on. With liquid fuel, the weight is variable based on the passengers, and the weight drops as the flight continues, thus increasing fuel efficiency the more weight is lost.