4 MWh Sale to Hungarian Reseller Partner

Invinity Energy Systems plc (AIM: IES) (OTCQX: IESVF), a leading global manufacturer of utility-grade energy storage, is pleased to announce the sale of a total of 4 MWh of VS3 vanadium flow batteries to Central European Vanadium Storage Kft, a subsidiary of Ideona Group ("Ideona") for use in two separate solar plus storage projects in Hungary. These sales are Invinity's second product order from Ideona, which also acts as the Company's partner in the region.

The batteries will be deployed alongside existing on-site solar arrays at two projects in western Hungary, which have been designed to receive grant funding support from the Hungarian government. 2 MWh of energy storage will be deployed at each site and will be used to stabilise solar output and provide flexibility to the local grid networks.

The Company has now received final notice to proceed from Ideona and therefore expects shipping to occur during Q4 2025. This order formed part of the "signed, uncommitted" category of Invinity's commercial orderbook disclosed in the Company's announcement on 9 September 2025.

Matt Harper, President at Invinity said:

"We're very pleased to have reached financial close on another sale in the Hungarian market alongside our partner Ideona, who have again chosen our VS3 product as most appropriate for the size and delivery timescale of this project. This is further validation of the tremendous capabilities our vanadium flow batteries can deliver alongside grid-connected solar generation. The Hungarian energy storage market remains an exciting growth area for Invinity, and we look forward to delivering this project as a step towards further expansion in the region."