External measurement system for checking battery charge state

The system for contactless measurement of the state of charge of an electric accumulator (100) is based on the existence of at least one electrode within the accumulator (110) which has a conductivity which varies as a function of the state of charge. The system includes a measurement circuit (140) including a coil (120) situated near to the accumulator, with further components for determining the complex impedance of the measurement circuit. The measurement circuit includes an LCR circuit with a generator (130) applying a periodic excitation, and a frequency response analyser providing an output with a component related to the complex impedance. This signal is relayed to a display (162). Both the modulus and the phase of the complex impedance are determined as part of the measurement. Dispositif de mesure sans contact électrique de l'état de charge d'un accumulateur électrique (100), caractérisé en ce qu'il comporte un circuit de mesure (140) comprenant au moins une bobine (120) apte à être disposée au voisinage de l'accumulateur, des moyens de mesure (130, 160) de la valeur d'au moins une composante de l'impédance du circuit de mesure, et des moyens d'affichage (162) d'une valeur proportionnelle à ladite composante valeur de la composante.