Regarding long term storage keep an eye on the UK's Cap and Floor scheme which offers guaranteed revenues to long term storage technologies [1].

Page 7 of https://www.ofgem.gov.uk/sites/default/files/2025-09/LDES%20... lists the technology types of the project applications. The majority are Li-Ion BESS, but there are also other battery chemistries and Liquid/Compress Air Storage

1. https://www.ofgem.gov.uk/press-release/super-battery-project...