Table 5 Possible figures of merit for evaluating PSC stability

1

T₈₀

Continuous stress

20% of PCE decay from initial PCE (t = 0).

2

T_S80

20% of PCE decay from a certain PCE value during the ageing experiment, corresponding to t = T_max or t = T_burn-in: from the extrapolated t = 0 value from the post-burn-in decay fitting (see Fig. 2e,f). For cells with an increase in PCE, T₈₀ should be estimated for time at which the efficiency has dropped to 80% of the maximum PCE, with the complete time from t = 0 to this point quoted as the T₈₀ value.

3

η₁₀₀₀ (PCE after 1000 h)

In case T₈₀ is not reached within the timeframe of the ageing experiment, so the decrease observed over first 1000 h should be reported in addition to (optionally) an extrapolation applied to determine T₈₀ and/or T_S80.

4

T₈₀ analogue, corrected for the recovery processes

If the restoration process has been tested after the stress removal.

5

T₉₅ and T_S95

Analogous to T₈₀ and T_S80, apart from to 95% of the t = 0, maximum, or post-burn-in back-extrapolated t = 0 PCE.

6

T₈₀ analogue for energy output per cycle or average PCE value during the cycle

Cycled stress

For cycled illumination conditions, especially in the case of non-monotonic PCE versus time curves.