Oil giant Shell has joined a raft of investors backing German energy storage group Sonnen.

Alongside the investment by Shell Ventures, Shell’s New Energies unit also inked a strategic cooperation agreement with Sonnen, one of the hottest tips to emerge as a leader in the fast-growing storage sector.

A partnership between Shell and Sonnen will “include innovative integrated energy propositions, enhanced EV charging solutions and the provision of grid services that are based on sonnen's virtual battery pool”, said a statement from the German company.