High power, extended temperature range-capable, highly abuse overcharge and discharge tolerant rechargeable battery cell and pack

An electrochemical cell comprising:

• a cathode, the cathode comprising a cathode electrochemically active polycrystalline material comprising the formula Li1+xMO2+y, wherein −0.9≤x≤0.3, −0.3≤y≤0.3, and wherein M comprises Ni at 80 atomic percent or higher relative to total M, wherein the cathode electrochemically active material includes a plurality of crystallites and a grain boundary between the plurality of crystallites, wherein the concentration of cobalt, aluminum, or both is higher in the grain boundary than in the center of the adjacent crystallites;
• two or more anodes comprising an anode electrochemically active material with an electrochemical redox potential of at least 400 mV vs Li/Li+;
• wherein the anode and the cathode independently further comprise a binder intermixed with the anode electrochemically active material and the cathode electrochemically active material respectively;
• the anode and the cathode each independently further comprise a current collector substrate comprising aluminium, wherein the cathode current collector is coated with respective electrochemically active material on two sides;
• a porous polyolefin separator;
• an electrolyte comprising a lithium salt and a carbonate solvent;
• wherein the two or more anodes are terminal layers of a stack of electrodes;
• and
• wherein a capacity ratio of anode to cathode is less than 1.