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The preparative electrosynthetic procedure for gram‐scale preparation of symmetric 4,4′‐dihydroxy‐3,3′‐diformylbiphenyls from salicylic aldehydes via the intermediate formation of ethylene‐bridged bis((2‐hydroxybenzylidene)imino)nickel (II) complexes is reported for the first time. This procedure represents a practical route to the variety of rare bisphenol derivatives. The electrochemical aryl‐aryl coupling via an oxidative CH – activation in NiSalens is exploited for facile and selective C−C bond formation.

Electrochemical cells using LiFePO4 cathode material are considered one of the safest and most resistant to overcharging among Li-ion batteries. However, if LiFePO4-based electrodes are exposed to high potentials, surface and structural changes may occur in the electrode material. In this study Li/LiFePO4 half-cells were overcharged under different modes with variable cut-off voltages and charge currents. The change in voltage profile, discharge capacity, surface layers composition, and crystalline structure were characterized after overcharge cycles. It was demonstrated that the cathode material is resistant to short-term overcharging up to 5 V, but undergoes irreversible changes with increasing overcharge time or potential. Thus, despite the well-known tolerance of LiFePO4-based batteries to overcharge, a long overcharge time or high cut-off voltage leads to destructive changes in the cathode and should be avoided.

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