Recent research developments in electronics and progresses in biotechonlogies gave rise to a new class of devices and tecniques which lead to systems able to hugely improve the quality of healthcare. Implanted neurostimulators are always more often taking place of drugs in classical polytherapy and being used to treat a variety of illnesses such as Parkinson or Ephilepsy. In some other cases neurostimulation is used to restore sensory inputs, restoring hearing to people with hearing loss or view to people with retinal problems . All these active devices require the use of batteries to deliver power and per-cutaneous cables to link the external device to the implanted one.