Four major Japanese oil companies have partnered to test a network of EV charging stations that will charge customers a flat monthly fee for unlimited juice.

Four major Japanese oil companies have partnered to test a network of EV charging stations that will charge customers a flat monthly fee for unlimited juice, JX Nippon Oil announced Monday.

The companies, JX Nippon, Idemitsu Kosan, Cosmo Oil and Showa Shell Sekiyu, will offer the service at 27 of their affiliated gas stations in the Tokyo region, starting in early 2012. Monthly fees start at 3,000 yen (about $38).

Public charging stations are slowly coming on line at different types of locations around the world – BP gas stations in the Netherlands, Cracker Barrel restaurants and Wal-mart stores in the US. It’s likely to take a few years of tests and pilots before it becomes clear what type of pricing model customers prefer.

Image: EV SERVICE STATION NETWORK