LI-ION CELLS WITH EXTREME FAST CHARGING CAPABILITIES

Rechargeable battery cells and methods for extreme fast charging are disclosed. For example, such a rechargeable battery cell might be chargeable to at least 70% of usable capacity within 15 minutes. Such a rechargeable battery cell may include an anode having at least one surface with a reversible areal capacity, after formation, up to 8.0 mAh/cm, containing a Si—C composite within a porous structure and including a carbon-based conductive additive, wherein the Si—C composite is at least 30% Si by weight, and the material is at least 85% Si—C composite. The rechargeable battery cell may also include a cathode having at least one surface with a reversible areal capacity, after formation, up to 6 mAh/cm, wherein a ratio of areal capacity of the at least one surface of the anode to the at least one surface of the cathode is between 1.15 to 1.45.