Electrical and engineering equipment manufacturer Harju Elekter acquired a 10% stake in Germany-based ultrcacapacitor producer Skeleton Technologies on Wednesday, providing €9.8m ($11m) in series B round funding, according to Life Size Media.
Up Invest, the investment firm that led Skeleton’s €3.9m series A round in July 2014, also participated in the round.
Skeleton produces graphene-based ultracapacitors for energy storage, and will use the latest funding to scale up its production to meet increasing demand and expand its 42-strong workforce.
Ultracapacitors are similar to batteries but are capable of storing significantly higher amounts of energy, recharge within seconds, and have up to a million recharging cycles, compared to the 500 to 1,500 cycles of current lithium-ion batteries.
Skeleton’s clients include hybrid lorry manufacturers, grid-scale energy storage companies and the European Space Agency.