To investigate the effects of further annealing on LNCl-I-BM we re-annealed LNCl-I-BM at 600°C for 3h and subsequent air-quenching restored the initial crystallinity of LNCl-I and the conductivity was reduced to 1•10 -3 mS cm -1 . Annealing LNCl-I-BM also increased the activation energy to 0.486 ± 0.005 eV which is close to the LNCl-I value of 0.471 ± 0.005 eV (Figure ). We thus conclude that the beneficial effects of mechanochemical milling on LNCl-I are reversed when annealing the ball milled samples. This result supports that the reduced particle size and the increased strain obtained after milling LNCl-I may potentially explain the increased Li conductivity of LNCl-I-BM.