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Page 10 of 13 Ahmed et al. Energy Mater. 2025, 5, 500079 https://dx.doi.org/10.20517/energymater.2024.209

Figure 6. Temperature dependence of inverse Haven ratio for two OIPCs [P ][TFSI] and [P 1224 ][PF ] (data taken from [21] ) in melted and
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solid states. The large error bars come from the uncertainties in estimation of mobile fraction [Supplementary Figure 2B].

Figure 7. Schematic presentation of OIPC consisting of crystalline fraction with relatively immobile ions and disordered fraction with
high mobile ions, but with strong ion-ion correlations.

We propose that because of the crystalline structure of OIPCs (although disordered), cation motion occurs
only through jumps between cation sites, while anions can only jump between anion sites. This might create
cooperative jumps where cations exchange positions with other cations and anions with other anions,
leading to high ion diffusion without contributing to long-range charge transport. Such ion exchange
motion can be considered as dynamical charge trapping, appearing as Process I in conductivity spectra. In
this scenario, the scale of cooperativity might exceed the size of the elementary unit cell, as previously
proposed , and probably depends on the structure of solid phases at different temperatures. As mentioned
[21]
above, according to our WAXS data, the aged sample exhibits a more disordered crystalline structure with a
higher fraction of mobile ions, which might explain why the aged sample has higher conductivity compared
to the fresh sample.