A heat storage in the form of latent heat with improved charging phase

A heat storage in the form of latent heat comprising a reservoir (102) containing a phase change material, two heat exchangers (104, 106) disposed outside the reservoir (102), the phase change material being in the reservoir, at least at the beginning of a charging phase, in part by solid phase forming an agglomerate (MCPS) in the tank bottom (2), said device comprising: - means (122) creating a taxiway in between the agglomerate (MCPS) and the reservoir (102) so as to ensure a circulation of the liquid phase change material between the agglomerate (MCPS) and a wall of the reservoir (102), and - means (124) providing a splitting volume of the agglomerate (MCPS) and a production of pure phase change material chips form a solid-liquid mixture flowing to the heat exchangers.