MUNICH (Reuters) – the automotive German BMW and its Japanese rival Toyota Motor plan to cooperate in investigations to develop cars electric, lithium-ion batteries told Reuters on Thursday, a source familiar with the topic.

In addition, over the weekend reported that both companies were in negotiations for a society to develop “green” cars. BMW would bring to the Japanese firm engines diesel.

It is expected that the two companies announce cooperation during a joint press conference scheduled for the 0700 Thursday in Tokyo, said the source.

Ni BMW or Toyota wanted to speak on the subject.

Bas Akio Toyoda, who became CEO in mid-2009, Toyota has forged partnerships with a number of companies, which include Microsoft, Salesforce.com, Tesla and Ford Motor Co. to jointly develop vans hybrids.

Earlier Tuesday, Toyota introduced a hybrid Prius which is loaded with a plug, with lithium-ion batteries high capacity.

The presentation was made before the Tokyo Motor Show and the model is promoted as the “green” car more practical in the world.

Electric cars usually sold twice what sells a conventional car that uses an engine combustion, so researchers are looking for ways that your batteries are lighter and that vehicles are less expensive.

(Report of Irene Preisinger in Munich and Kim Chang-Ran in Tokyo.) Written by Victoria Bryan. (Edited in Spanish by Gabriela Donoso)