Mitsubishi joins a host of top investors, including European power utilities, that are exploring off-grid technology as a way of expanding their exposure to renewables and tapping new pools of customers.

"The funding is further evidence of Japanese interest in Africa and in (pay-as-you-go) solar energy globally," BBOXX Chief Executive Mansoor Hamayun said in a statement.

Founded in 2010, the company has installed around 200,000 solar home systems, which allow customers without access to a reliable grid to power lights and small appliances.

Mitsubishi was the majority investor in the series D funding round - the fourth round of seed funding - which BBOXX said would help accelerate growth in Africa, where it already operates in 12 countries, and allow for an expansion into Asia.

Other investors included ENGIE Rassembleurs d'Energies, an initiative of the ENGIE that gives financial support to projects contributing to sustainable energy access for vulnerable populations.

Bamboo Capital Partners, DOEN Participaties and MacKinnon, Bennett & Company also participated in the funding round.

France's EDF Group took a 50% stake in BBOXX's operation in Togo last year. African Infrastructure Investment Managers (AIIM), a private equity fund manager, paid $31 million for a minority stake in the company in January.

(Reporting by Joe Bavier, editing by Deepa Babington)