Batteries used in electric vehicles may soon be cheaper if a strategy being tested by a United States battery maker and a major Japanese conglomerate works out successfully.

EnerDel, the only lithium-ion battery producer in the United States for the electric vehicle market, is partnering with the real estate arm of Japan’s Itochu Corporation to develop a “secondary market” for lithium-ion batteries.

The idea is to sell E.V. batteries to community or residential grid storage systems once they have outlived their usefulness for the vehicles.

In the secondary market, such as storage systems for apartment buildings, a battery with significant storage capacity remaining can be redeployed, or what EnerDel calls “secondary use.”

The residual life in the battery can be spent in the secondary market since they cannot be used anymore in vehicles where battery performance requirements are more taxing.

In their team-up, EnerDel will supply advanced battery systems for a residential electricity grid to be installed in an apartment building near Tokyo.

In the future, Itochu Property Development Limited will introduce the secondary use system to 20 percent of its new apartment buildings.

EnerDel said viable battery aftermarket could lower upfront costs for automotive buyers as the cost of the battery can be spread over its useful life, which factors in secondary users.

EnerDel quoted analysts who predicted that the secondary market opportunity for lithium-ion batteries could be two to three times the size of the automotive market opportunity over time.

“The system will provide a critical link between renewable energy, high-speed charging for electric cars and the local utility grid,” the company said in a statement.

The partnership is the second project EnerDel had with Itochu after teaming up with Mazda on a smart grid system. This project used vehicles converted to electric drive through a platform designed and built by EnerDel and Norwegian E.V. maker Think.

EnerDel was previously selected to supply the batteries that will power a Department of Energy-funded smart grid energy storage project. Done at Portland General Electric in Oregon, it will help manage peak demand and smooth the variations in power from renewable sources such as wind and solar.