Devices and methods comprising supercapacitor-emulating fast-charging batteries

A device comprising control circuitry and a modified fast-charging lithium ion battery having Si, Ge and/or Sn based anode active material and designed to operate at 5 C at least and within an operation range of 5% at most around a working point of between 60-80% lithiation of the Si, Ge and/or Sn-based anode active material, wherein the control circuitry is configured to maintain a state of charge (SoC) of the battery within the operation range around the working point:

• wherein the anode active material is configured to enable operation of the modified fast-charging lithium ion battery only around the working point and within the operation range;
• wherein an anode of the modified fast-charging lithium ion battery comprises mechanical barriers configured to prevent full expansion of the anode material upon lithiation;
• and
• wherein the anode material comprises composite anode material particles having shell structures which are smaller than a full expansion volume of cores of the composite anode material particles.