Abstract: Formation process for a potassium-ion hybrid supercapacitor, the process comprising: a) supplying the potassium-ion hybrid supercapacitor comprising: a negative electrode comprising graphite, a positive electrode comprising activated carbon, an electrolyte comprising a potassium salt, b) charging the supercapacitor at constant current in a protocol of between Cx/50 and Cx/2, to a charge cutoff voltage of between 3.0 V and 3.3 V, c) holding the supercapacitor at the charge cutoff voltage until the leakage current is between Cx/2000 and Cx/500, d) discharging the supercapacitor at constant current in a protocol of between Cx/50 and Cx, to a discharge cutoff voltage of between 0 V and 2 V, where the process further comprises degassing the supercapacitor after one of steps b) to d).

Abstract: Lithium electrochemical accumulator including at least one first package housing at least one electrochemical cell, said first package including at least: one internal thermally insulating layer suitable for confining, to the interior of a first package, the heat given off even in case of abnormal operation of a cell C and for protecting the cell(s) from heat generated outside the first package; one external layer superposed on the internal layer, the external layer being mechanically strong and fire resistant; and one cooling device including at least one heat pipe the enclosure of which passes through the first package(s) in a seal-tight manner and such that the heated zone of the heat pipe(s) is located inside the first package(s) and that the cooled zone of the heat pipe(s) is located outside the first package(s).