FILE PHOTO - An electric Volkswagen car is plugged into a recharging point in central London, Britain November 10, 2016. REUTERS/Toby Melville

(Reuters) - Volkswagen VOWG_p.DE unit Electrify America said on Thursday it has entered into an agreement with electric vehicle fleet charging company Stable Auto to deploy charging services using robot technology for self-driving electric vehicles.

The companies said they would start a pilot project in San Francisco and expects the facility could open early next year.

The charging facility will allow self-driving EV fleets to charge with no operators around.

Under the agreement, Reston, Virginia-based Electrify America will evaluate the hardware, network, operations and billing of its charging systems while Stable Auto will manage the overall project and pair its robotic technology and advanced scheduling software at its facility with Electrify America’s chargers.

Major automakers including General Motors Co have announced plans to invest tens of billions of dollars on electric vehicles over the next few years, in a direct challenge to Tesla Inc.

But a lack of infrastructure for U.S. drivers to recharge electric vehicles is seen as a major barrier to mass adoption of the cars as consumers remain concerned over limited ranges.